Platelet–Leukocyte Hybrid Membrane‐Coated Immunomagnetic Beads for Highly Efficient and Highly Specific Isolation of Circulating Tumor Cells

Biomimetic cell‐membrane‐camouflaged nanoparticles with desirable features have been widely used for various biomedical applications. However, the current research focuses on single cell membrane coating and using multiple cell membranes for nanoparticle functionalization is still challenging. In this work, platelet (PLT) and leukocyte (WBC) membranes are fused, PLT–WBC hybrid membranes are coated onto magnetic beads, and then their surface is modified with specific antibodies. The resulting PLT–WBC hybrid membrane‐coated immunomagnetic beads (HM‐IMBs) inherit enhanced cancer cell binding ability from PLTs and reduce homologous WBC interaction from WBCs, and are further used for highly efficient and highly specific isolation of circulating tumor cells (CTCs). By using spiked blood samples, it is found that, compared with commercial IMBs, the cell separation efficiency of HM‐IMBs is improved to 91.77% from 66.68% and the cell purity is improved to 96.98% from 66.53%. Furthermore, by using the HM‐IMBs, highly pure CTCs are successfully identified in 19 out of 20 clinical blood samples collected from breast cancer patients. Finally, the robustness of HM‐IMBs is verified in downstream CTC analysis such as the detection of PIK3CA gene mutations. It is anticipated that this novel hybrid membrane coating strategy will open new possibilities for overcoming the limitations of current theranostic platforms.     

Highly Efficient Quantum‐Dot‐Sensitized Solar Cell Based on Co‐Sensitization of CdS/CdSe

Cadmium sulfide (CdS) and cadmium selenide (CdSe) quantum dots (QDs) are sequentially assembled onto a nanocrystalline TiO₂ film to prepare a CdS/CdSe co‐sensitized photoelectrode for QD‐sensitized solar cell application. The results show that CdS and CdSe QDs have a complementary effect in the light harvest and the performance of a QDs co‐sensitized solar cell is strongly dependent on the order of CdS and CdSe respected to the TiO₂. In the cascade structure of TiO₂/CdS/CdSe electrode, the re‐organization of energy levels between CdS and CdSe forms a stepwise structure of band‐edge levels which is advantageous to the electron injection and hole‐recovery of CdS and CdSe QDs. An energy conversion efficiency of 4.22% is achieved using a TiO₂/CdS/CdSe/ZnS electrode, under the illumination of one sun (AM1.5,100 mW cm^?2). This efficiency is relatively higher than other QD‐sensitized solar cells previously reported in the literature.     

An O2 Self‐Sufficient Biomimetic Nanoplatform for Highly Specific and Efficient Photodynamic Therapy

Conventional oxygen‐dependent photodynamic therapy (PDT) has faced severe challenges because of the non‐specificity of most available photosensitizers (PSs) and the hypoxic nature of tumor tissues. Here, an O₂ self‐sufficient cell‐like biomimetic nanoplatform (CAT‐PS‐ZIF@Mem) consisting of the cancer cell membrane (Mem) and a cytoskeleton‐like porous zeolitic imidazolate framework (ZIF‐8) with the embedded catalase (CAT) protein molecules and Al(III) phthalocyanine chloride tetrasulfonic acid (AlPcS₄, defined as PS) is developed. Because of the immunological response and homologous targeting abilities of the cancer cell membrane, CAT‐PS‐ZIF@Mem is selectively accumulated at the tumor site and taken up effectively by tumor cells after intravenous injection. After the intracellular H₂O₂ penetration into the framework, it is catalyzed by CAT to produce O₂ at the hypoxic tumor site, facilitating the generation of toxic ¹O₂ for highly effective PDT in vivo under near‐infrared irradiation. By integrating the immune escape, cell homologous recognition, and O₂ self‐sufficiency, this cell‐like biomimetic nanoplatform demonstrates highly specific and efficient PDT against hypoxic tumor cells with much reduced side‐effect on normal tissues.     

Ethanol‐Dispersed Polymer Nanofibers as a Highly Selective Cell Isolation and Release Platform for CD4+ T Lymphocytes

A novel cell isolation and release platform using electrospun polystyrene‐poly(styrene‐co‐maleic anhydride) (PS‐PSMA) nanofibers is presented. Ethanol treatment of PS‐PSMA nanofibers, employed for the purpose of sterilization, significantly increases their inter‐fiber space for both antibody conjugation and subsequent cell separation. For the selective isolation of CD4⁺ T cells from heterogeneous mixtures of mouse lymph nodes, capture efficiencies of up to 100% are achieved while maintaining cellular integrity and viability. Once captured, CD4⁺ T lymphocytes can also be released from the NF scaffolds, further demonstrating its potential functionality as an immune cell‐supporting and releasing matrix. This is the first demonstration of lymphocyte‐culture scaffolds enabling selective isolation, accommodation, and sustained release of CD4⁺ T cells for the purpose of cell therapies.     

BiCMOS工艺的高线性度下变频混频器设计

利用BiCMOS工艺设计了一种高线性度下变频混频器.在此变频混频器的设计中结合了双极型工艺在射频段的高性能以及MOS工艺的高线性度,并利用其对传统的吉尔伯特单元进行了优化.基于JAZZ 0.35μm标准BiCMOS SBC35工艺设计参数对混频器进行了设计和仿真,仿真结果表明该混频器获得了良好的性能指标,转换增益为9.3 dB,输入3阶互调点达到了16 dBm,在5 V单电源下消耗1.9 mA的电流.     

Highly Elastic Micropatterned Hydrogel for Engineering Functional Cardiac Tissue

Heart failure is a major international health issue. Myocardial mass loss and lack of contractility are precursors to heart failure. Surgical demand for effective myocardial repair is tempered by a paucity of appropriate biological materials. These materials should conveniently replicate natural human tissue components, convey persistent elasticity, promote cell attachment, growth and conformability to direct cell orientation and functional performance. Here, microfabrication techniques are applied to recombinant human tropoelastin, the resilience‐imparting protein found in all elastic human tissues, to generate photocrosslinked biological materials containing well‐defined micropatterns. These highly elastic substrates are then used to engineer biomimetic cardiac tissue constructs. The micropatterned hydrogels, produced through photocrosslinking of methacrylated tropoelastin (MeTro), promote the attachment, spreading, alignment, function, and intercellular communication of cardiomyocytes by providing an elastic mechanical support that mimics their dynamic mechanical properties in vivo. The fabricated MeTro hydrogels also support the synchronous beating of cardiomyocytes in response to electrical field stimulation. These novel engineered micropatterned elastic gels are designed to be amenable to 3D modular assembly and establish a versatile, adaptable foundation for the modeling and regeneration of functional cardiac tissue with potential for application to other elastic tissues.     

Highly Efficient Self‐Healable and Dual Responsive Cellulose‐Based Hydrogels for Controlled Release and 3D Cell Culture

To face the increasing demand of self‐healing hydrogels with biocompatibility and high performances, a new class of cellulose‐based self‐healing hydrogels are constructed through dynamic covalent acylhydrazone linkages. The carboxyethyl cellulose‐graft‐dithiodipropionate dihydrazide and dibenzaldehyde‐terminated poly(ethylene glycol) are synthesized, and then the hydrogels are formed from their mixed solutions under 4‐amino‐DL‐phenylalanine (4a‐Phe) catalysis. The chemical structure, as well as microscopic morphologies, gelation times, mechanical and self‐healing performances of the hydrogels are investigated with ¹H NMR, Fourier transform infrared spectroscopy, atomic force microscopy, rheological and compression measurements. Their gelation times can be controlled by varying the total polymer concentration or 4a‐Phe content. The resulted hydrogels exhibit excellent self‐healing ability with a high healing efficiency (≈96%) and good mechanical properties. Moreover, the hydrogels display pH/redox dual responsive sol‐gel transition behaviors, and are applied successfully to the controlled release of doxorubicin. Importantly, benefitting from the excellent biocompatibility and the reversibly cross‐linked networks, the hydrogels can function as suitable 3D culture scaffolds for L929 cells, leading to the encapsulated cells maintaining a high viability and proliferative capacity. Therefore, the cellulose‐based self‐healing hydrogels show potential applications in drug delivery and 3D cell culture for tissue engineering.     

Highly conductive p + + ‐AlGaAs/n + + ‐GaInP tunnel junctions for ultra‐high concentrator solar cells

Tunnel junctions are key for developing multijunction solar cells (MJSC) for ultra‐high concentration applications. We have developed a highly conductive, high bandgap p ^{+ +} ‐AlGaAs/n ^{+ +} ‐GaInP tunnel junction with a peak tunneling current density for as‐grown and thermal annealed devices of 996 A/cm ² and 235 A/cm ², respectively. The J–V characteristics of the tunnel junction after thermal annealing, together with its behavior at MJSCs typical operation temperatures, indicate that this tunnel junction is a suitable candidate for ultra‐high concentrator MJSC designs. The benefits of the optical transparency are also assessed for a lattice‐matched GaInP/GaInAs/Ge triple junction solar cell, yielding a current density increase in the middle cell of 0.506 mA/cm ² with respect to previous designs. Copyright © 2014 John Wiley & Sons, Ltd.     

Oxygen‐Free Highly Conductive Graphene Papers

Graphene papers have a potential to overcome the gap from nanoscale graphene to real macroscale applications of graphene. A unique process for preparation of highly conductive graphene thin paper by means of Ar⁺ ion irradiation of graphene oxide (GO) papers, with carbon/oxygen ratio reduced to 100:1, is presented. The composition of graphene paper in terms of carbon/oxygen ratio and in terms of types of individual oxygen‐containing groups is monitored throughout the process. Angle‐resolved high resolution X‐ray photoelectron spectroscopy helps to investigate the depth profile of carbon and oxygen within reduced GO paper. C/O ratios over 100 on the surface and 40 in bulk material are observed. In order to bring insight to the processes of oxygen removal from GO paper by low energy Ar⁺ ion bombardment, the gases released during the irradiation are analyzed by mass spectroscopy. It is proven that Ar⁺ ion beam can be applied as a technique for fabrication of highly reduced graphene papers with high conductivities. Such highly conductive graphene papers have great potential to be used in application for construction of microelectronic and sensor devices.     

Highly Luminescent Organosilane‐Functionalized Carbon Dots

The first use of an organosilane as a coordinating solvent to synthesize highly luminescent (quantum yield = 47%) amorphous carbon dots (CDs) in one minute is reported. The CDs, which benefit from surface methoxysilyl groups, have a diameter of ~0.9 nm and can easily be fabricated into pure CD fluorescent films or monoliths simply by heating them at 80 ºC for 24 h. Moreover, the non‐water‐stable CDs can be further transformed into water‐soluble CDs/silica particles, which are biocompatible with and nontoxic to the selected cell lines in our preliminary evaluation. The proposed novel synthetic route is believed to provide an alternative synthesis route and should inspire more research into the origin and applications of CDs, as well as delivering CD‐based materials.     

Highly transparent singlet fission solar cell with multistacked thin metal contacts for tandem applications

Singlet fission solar cells combined with silicon photovoltaics allow the construction of parallel tandem solar cells, which benefit from better usage of high‐energy photons. A key limiting factor for the performance of such a tandem configuration is the transparency of the singlet fission front cell. Here we show highly transparent singlet fission solar cells with a top contact of thin Ca:Ag blends. The optimized contact leads to 81% average solar cell transmittance in the near‐infrared while maintaining more than half the short‐circuit current density compared with an opaque device. We simulate the performance of the parallel tandem stack and assess the improvements needed to fully realize the potential of singlet fission in this device configuration.     

Highly Conductive Carbon Nanotube‐Graphene Hybrid Yarn

An efficient procedure for the fabrication of highly conductive carbon nanotube/graphene hybrid yarns has been developed. To start, arrays of vertically aligned multi‐walled carbon nanotubes (MWNT) are converted into indefinitely long MWNT sheets by drawing. Graphene flakes are then deposited onto the MWNT sheets by electrospinning to form a composite structure that is transformed into yarn filaments by twisting. The process is scalable for yarn fabrication on an industrial scale. Prepared materials are characterized by electron microscopy, electrical, mechanical, and electrochemical measurements. It is found that the electrical conductivity of the composite MWNT‐graphene yarns is over 900 S/cm. This value is 400% and 1250% higher than electrical conductivity of pristine MWNT yarns or graphene paper, respectively. The increase in conductivity is asssociated with the increase of the density of states near the Fermi level by a factor of 100 and a decrease in the hopping distance by an order of magnitude induced by grapene flakes. It is found also that the MWNT‐graphene yarn has a strong electrochemical response with specific capacitance in excess of 111 Fg^?1. This value is 425% higher than the capacitance of pristine MWNT yarn. Such substantial improvements of key properties of the hybrid material can be associated with the synergy of MWNT and graphene layers in the yarn structure. Prepared hybrid yarns can benefit such applications as high‐performance supercapacitors, batteries, high current capable cables, and artificial muscles.     

Highly Efficient Video Codec for Entertainment‐Quality

We present a novel video codec for supporting entertainment‐quality video. It has new coding tools such as an intra prediction with offset, integer sine transform, and enhanced block‐based adaptive loop filter. These tools are used adaptively in the processing of intra prediction, transform, and loop filtering. In our experiments, the proposed codec achieved an average reduction of 13.35% in BD‐rate relative to H.264/AVC for 720p sequences.     

Highly Robust AHHVSCR‐Based ESD Protection Circuit

In this paper, a new structure for an advanced high holding voltage silicon controlled rectifier (AHHVSCR) is proposed. The proposed new structure specifically for an AHHVSCR‐based electrostatic discharge (ESD) protection circuit can protect integrated circuits from ESD stress. The new structure involves the insertion of a PMOS into an AHHVSCR so as to prevent a state of latch‐up from occurring due to a low holding voltage. We use a TACD simulation to conduct a comparative analysis of three types of circuit — (i) an AHHVSCR‐based ESD protection circuit having the proposed new structure (that is, a PMOS inserted into the AHHVSCR), (ii) a standard AHHVSCR‐based ESD protection circuit, and (iii) a standard HHVSCR‐based ESD protection circuit. A circuit having the proposed new structure is fabricated using 0.18 μm Bipolar‐CMOS–DMOS technology. The fabricated circuit is also evaluated using Transmission‐Line Pulse measurements to confirm its electrical characteristics, and human‐body model and machine model tests are used to confirm its robustness. The fabricated circuit has a holding voltage of 18.78 V and a second breakdown current of more than 8 A.     

Highly efficient and mechanically robust stretchable polymer solar cells with random buckling

Stretchable polymer solar cells have shown great potential as stretchable power generators for applications in stretchable electronics, such as wearable electronics, electronic skins and stretchable displays. However, their mechanical stability and power conversion efficiency (PCE) thus are still far below the requirement for the practical applications. Here, we have developed highly efficient and stretchable polymer solar cells (PSCs) based on a random buckling process. The stretchable PSCs are fabricated by attaching the ultrathin PSC onto a pre-stretched elastomeric substrate and then releasing the prestrain to form random bucklings. Its PCE of 5.8% under 70% tensile strain is the largest to date among the reported PSCs. The stretchable PSCs exhibit small fluctuations in performance after 400 stretching-releasing cycles. This is an important step towards producing stretchable PSCs for commercial applications.