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In this study, Ag@SiO2 nanoparticles were synthesized by a modified St&ouml, ber method for preparing the TiO2 mesoporous layer of carbon counter electrode-based perovskite solar cells (PSCs) without a hole transporting layer. Compared with normal PSCs (without Ag@SiO2 incorporated in the TiO2 mesoporous layer), PSCs with an optimal content of Ag@SiO2 (0.3 wt. % Ag@SiO2-TiO2) show a 19.46% increase in their power conversion efficiency, from 12.23% to 14.61%, which is mainly attributed to the 13.89% enhancement of the short-circuit current density, from 20.23 mA/cm2 to 23.04 mA/cm2. These enhancements mainly contributed to the localized surface Plasmon resonance effect and the strong scattering effect of Ag@SiO2 nanoparticles. However, increasing the Ag@SiO2 concentration in the mesoporous layer past the optimum level cannot further increase the short-circuit current density and incident photon-to-electron conversion efficiency of the devices, which is primarily ascribed to the electron transport pathways being impeded by the insulating silica shells inside the TiO2 network.

Targeted therapy is highly challenging and urgently needed for patients diagnosed with triple negative breast cancer (TNBC). Here, a synergistic treatment platform with plasmonic–magnetic hybrid nanoparticle (lipids, doxorubicin (DOX), gold nanorods, iron oxide nanocluster (LDGI))–loaded mesenchymal stem cells (MSCs) for photoacoustic imaging, targeted photothermal therapy, and chemotherapy for TNBC is developed. LDGI can be efficiently taken up into the stem cells with good biocompatibility to maintain the cellular functions. In addition, CXCR4 on the MSCs is upregulated by iron oxide nanoparticles in the LDGI. Importantly, the drug release and photothermal therapy can be simultaneously achieved upon light irradiation. The released drug can enter the cell nucleus and promote cell apoptosis. Interestingly, light irradiation can control the secretion of cellular microvehicles carrying LDGI for targeted treatment. A remarkable in vitro anticancer effect is observed in MDA‐MB‐231 with near‐infrared laser irradiation. In vivo studies show that the MSCs‐LDGI has the enhanced migration and penetration abilities in the tumor area via both intratumoral and intravenous injection approaches compared with LDGI. Subsequently, MSCs‐LDGI shows the best antitumor efficacy via chemo‐photothermal therapy compared to other treatment groups in the TNBC model of nude mice. Thus, MSCs‐LDGI multifunctional system represents greatly synergistic potential for cancer treatment.

Targeted delivery of nanomedicines into the tumor site and improving the intratumoral distribution remain challenging in cancer treatment. Here, we report an effective transportation system utilizing both of mesenchymal stem cells (MSCs) and their secreted microvesicles containing assembled gold nanostars (GNS) for targeted photothermal therapy of prostate cancer. The stem cells act as a cell carrier to actively load and assemble GNS into the lysosomes. Accumulation of GNS in the lysosomes facilitates the close interaction of nanoparticles, which could result in a 20 nm red-shift of surface plasmon resonance of GNS with a broad absorption in the near infrared region. Moreover, the MSCs can behave like an engineering factory to pack and release the GNS clusters into microvesicles. The secretion of GNS can be stimulated via light irradiation, providing an external trigger-assisted approach to encapsulate nanoparticles into cell derived microvesicles. In vivo studies demonstrate that GNS-loaded MSCs have an extensive intratumoral distribution, as monitored via photoacoustic imaging, and efficient antitumor effect under light exposure in a prostate-cancer subcutaneous model by intratumoral and intravenous injection. Our work presents a light-responsive transportation approach for GNS in combination of MSCs and their extracellular microvesicles and holds the promise as an effective strategy for targeted cancer therapy including prostate cancer.

In this study, Ag nanoparticles with diverse particle size and concentration, fabricated via the polyol method, were embedded in a TiO2 compact film to improve the power conversion efficiency of perovskite solar cells. Obtained results showed that Ag nanoparticles embedded in the TiO2 compact film do not affect the crystal structure of TiO2, while the size of the Ag nanoparticles can strongly influence the light absorption capacity of perovskite materials. However, the absorption intensity and power conversion efficiency of perovskite cells decreased with the increase in size of Ag nanoparticles. The amount of Ag nanoparticles was also an important factor for the performance of perovskite solar cells, and Ag nanoparticles in the compact layer were optimized to measure 10 nm in diameter, being embedded at a molar ratio of 1.5% (Ag:Ti = 1.5 mol%). Compared with hole-conductor-free perovskite solar cells that use carbon as counter electrodes, without Ag nanoparticles incorporated in the compact film, the enhanced efficiency of cells developed in this study can be mainly ascribed to the accelerated charge transfer, decreased charge recombination, and enhanced light absorption of the perovskite material in the visible region.

Framing detection has emerged to be an important topic in recent natural language processing research. Although several frameworks have been proposed, little is known about how to detect temporal discriminant frames. This study proposes a framework for discovering temporal discriminant frames, with a focus on identifying emergent frames in news discussions of illegal immigration issue. Built on joint non-negative matrix factorization (NMF), we propose the njNMF algorithm, an improved joint matrix factorization algorithm, to detect the temporal frames. We conducted experiments using the njNMF algorithm to identify emergent frames. The results of our experiments show that framing of illegal immigration changes over time, from human trafficking frames, to more recent economic and criminality frames. These findings suggest the utility of our temporal framing approach and can be used as a framing detection tool for policy researchers to understand the role of news framing in public agenda setting.

We designed and explored self-assembled gold nanoparticles (SAGNPs) by introducing dithiol modified polyethylene glycol (PEG) for internanoparticle cross-linking. SAGNPs could enhance uptake into cancer cells and be disintegrated by glutathione (GSH) to achieve tumor microenvironment-activated biodegradation. This assembled structure improved the photothermal effect compared to single gold nanospheres.

Remote control of cells and the regulation of cell events at the molecular level are of great interest in the biomedical field. In addition to chemical compounds and genes, mechanical forces play a pivotal role in regulating cell fate, which have prompted the rapid growth of mechanobiology. From a perspective of nanotechnology, magnetic nanomaterials (MNs) are an appealing option for mechanotransduction due to their capabilities in spatiotemporal manipulation of mechanical forces via the magnetic field. As a newly developed paradigm, magneto-mechanotransduction is harnessed to physically regulate cell fate for biomedical applications. Here, the critical factors that determine the magnetomechanical forces induced by MNs in mechanotransduction are briefly reviewed. Recent innovative approaches and their underlying mechanisms for controlling cell fate are highlighted, which offer possibilities for the remote mechanical manipulation of cells and biomolecules in a precise manner. Promising applications including regenerative medicine and cancer treatment based on magnetomechanical stimulation through MNs are also addressed. Perspectives and challenges in MN-based mechanotransduction are commented.

In this study, Ag/nano-TiO2 composites were prepared and introduced into a compact film of perovskite solar cells. A new method was used to create a compact precursor solution consisting of a mixture of ethanol, titanium diisopropoxide bis, and silver nitrate. The Ag/nano-TiO2 composite compact film was formed by spin-coating a compact precursor solution on a fluorine-doped tin-oxide substrate after annealing at 500 °C for 30 min. The Ag/nano-TiO2 composites were observed with a transmission electron microscope. The perovskite solar cells with different contents of the Ag/nano-TiO2 composite compact film were entirely fabricated in ambient air and based on carbon counter electrodes with diverse power conversion efficiency. The addition of Ag to the nano-TiO2 strengthened the optical absorption of the perovskite solar cells in the visible light region and enhanced the efficiency of electron injection in the perovskite solar cell; this result was mainly ascribed to the strong scattering effect and the surface plasmon resonance effect of the metallic Ag nanoparticles in the Ag/nano-TiO2 composite compact film. Because of the enhancement of electron injection, a small content of Ag/nano-TiO2 composite compact film improved the performance of the perovskite solar cell. Moreover, a perovskite solar cell with 1.5% Ag/nano-TiO2 composite compact film possessed the highest power conversion efficiency (η = 8.96%) and short-circuit photocurrent density (J sc) (=20.42 mA cm−2), resulting in a 30% enhancement in power conversion efficiency and a 23% enhancement in J sc when compared to the pristine TiO2 perovskite solar cell.

Based on the extended Huygens–Fresnel integral, the analytical formulae for the cross-spectral density matrix of the partially coherent radially polarized beams diffracted at a circular aperture in turbulent atmosphere are derived. The unapertured and free-space cases can be viewed as the special cases of our general result. By using the degree of coherence formula, the spatial correlation properties of the apertured partially coherent radially polarized beams in turbulent atmosphere are studied. The analyses indicate that the spatial correlation of the apertured partially coherent radially polarized beams are more affected by the atmospheric turbulence with the larger structure constant, the smaller truncation parameter, the larger coherence length, and the farther propagation distance.

In cells, mechanical forces play a key role in impacting cell behaviors, including adhesion, differentiation, migration, and death. Herein, a 20 nm mitochondria-targeted zinc-doped iron oxide nanocube is designed as a nanospinner to exert mechanical forces under a rotating magnetic field (RMF) at 15 Hz and 40 mT to fight against cancer. The nanospinners can efficiently target the mitochondria of cancer cells. By means of the RMF, the nanocubes assemble in alignment with the external field and produce a localized mechanical force to impair the cancer cells. Both in vitro and in vivo studies show that the nanospinners can damage the cancer cells and reduce the brain tumor growth rate after the application of the RMF. This nanoplatform provides an effective magnetomechanical approach to treat deep-seated tumors in a spatiotemporal fashion.

As an important part of perovskite solar cells (PSCs), the compact electron transport layer largely determines the performance of devices. Titanium dioxide (TiO2) and tin dioxide (SnO2) are very common materials for the electron transport layer (ETL) in PSCs. However, less has been reported regarding the development of high efficiency mesoporous PSCs based on a SnO2 compact layer. Herein, we prepared Mg doped modified SnO2 film at high temperature, combined it with TiO2 to form a composite compact layer, and then applied PSCs with the mesoporous structure. Compared with the pristine SnO2 compact layer, the composite compact layer has excellent interface contact with perovskite and higher electronic extraction capacity. Moreover, the defect free contact between TiO2 and FTO provides stronger hole blocking ability. Devices based on composite compact layers have almost no hysteresis effect. With the composite compact layer, the devices achieved a champion PCE of 13.01%, which is a 9.79% increase compared to the pristine SnO2 compact layer device.

The peroxidase-like functionality of iron oxide (IO) nanoparticles has attracted substantial attention in cancer treatment by reactive oxygen species (ROS) catalytic over-generation. However, the inefficient intracellular ROS generation still hurdles ready-to-use application of IO nanoparticles, attributing to the transient lifetime and limited diffusion distance of ROS. Indeed, excessive ROS generation in mitochondria is desirable to enhance cell death against cancer cells. In this study, we designed zinc-doped magnetic nanoparticles (MNPs) conjugated with triphenylphosphonium (TPP) for mitochondrial targeting. Moreover, the nanoparticles with high absorbance in visible region can catalyze ROS overproduction under visible light irradiation. Our platform provides a novel application of MNPs in targeted cancer therapy, which serves as a light-controlled switch to accelerate ROS generation and induce incremental cellular death.

The paper studied the relationship between the light spot position and the output voltage in the case of laser spot which is in the four-quadrant (4Q) detector whose shape is circle or elliptic, energy distribution uniform or Gaussian. The study is based on add–subtract algorithm, diagonal algorithm and difference over sum (Δ/∑) algorithm. By using methods of polynomial fitting it can get a simple polynomial expression to enhance measuring speed and the simulation error is given. A method of using Binary Optics Elements (BOE) to shape the laser beam in the 4Q detector to square light spot with uniform intensity distribution is proposed to expand linear measurement range. The simulation result is verified for a circular spot with Gaussian energy distribution.

The lasting popularity of many social Q&A websites, such as Yahoo! Answers and ResearchGate, has become valuable knowledge repositories for people to search for answers to questions in various aspects in life. Finding the most relevant questions is often a non-trivial task, and a fine-grained classification system of questions will be an important aid. Existing work mainly focused on classifying questions into different major categories (e.g., "Health","Computer", etc.) without further dealing with the fine-grained categories (e.g., "Dental","Skin Conditions", etc.). Identifying questions' finegrained categories is challenging due to the limited length of a question and insufficient content information available in these social Q&A websites. In this work, we propose a novel framework to classify questions into fine-grained categories based on enriching the related topics of questions. We leverage word embedding feature representation with topic modelings to determine the extended feature terms, i.e., terms that do not appeared in original question content. The enriched features then are used for fine-grained category classification. Extensive experiment results based on three large data collections showcase the effectiveness of our proposed approach.

Herein, the low-cost and eco-friendly zinc cation (Zn2+) is used to replace part of the lead cation (Pb2+) in methylammonium lead iodide (CH3NH3PbI3). The modified perovskite material, CH3NH3PbxZn1-xI3, is then obtained and successfully applied in the construction of hole-conductor-free perovskite solar cells (PSCs) based on carbon counter electrodes. The obtained PSCs with 1 mol% Zn doping dramatically facilitate the formation of dense, high surface coverage perovskite films with large grain size and superior crystallinity. Especially, the power conversion efficiency is up to 15.37%, which is a 14.8% increase, compared to the pristine PSCs. This work finds a superior way to further research lead-reduced PSCs.

Good quality Sn-doped In2O3 films with thickness of 30 nm were deposited using a vapor deposition technique known as pulsed electron deposition. The films were deposited on (100) Si substrates, at room temperature from a ceramic target of indium tin oxide (90/10). A pulsed electron beam was used for ablation of the target. Voltage of the electron source was maintained at 18 kV with frequency of pulses at 3 Hz. Distance between source and target was maintained around 6 mm, and the substrate to target distance was ∼7 cm. Oxygen pressure in the chamber during growth was varied from 3.1 to 20 mTorr. To evaluate the quality of grown films, various characterization techniques were employed. The effect of oxygen chamber pressure on resistivity (ρ), carrier concentration (N), mobility (μ), and optical constants (n and k) was carried out. Optical transparency and electrical conductivity of the films were seen to improve with increasing oxygen pressure. Details about the film preparation and evaluation of properties are reported.Good quality Sn-doped In2O3 films with thickness of 30 nm were deposited using a vapor deposition technique known as pulsed electron deposition. The films were deposited on (100) Si substrates, at room temperature from a ceramic target of indium tin oxide (90/10). A pulsed electron beam was used for ablation of the target. Voltage of the electron source was maintained at 18 kV with frequency of pulses at 3 Hz. Distance between source and target was maintained around 6 mm, and the substrate to target distance was ∼7 cm. Oxygen pressure in the chamber during growth was varied from 3.1 to 20 mTorr. To evaluate the quality of grown films, various characterization techniques were employed. The effect of oxygen chamber pressure on resistivity (ρ), carrier concentration (N), mobility (μ), and optical constants (n and k) was carried out. Optical transparency and electrical conductivity of the films were seen to improve with increasing oxygen pressure. Details about the film preparation and evaluation of propertie...

OBJECTIVE: To evaluate the orthopedic effect of presurgical nasoalveolar molding (PNAM) devices on the palatal deformities in unilateral complete cleft lip and palate (UCCLP) patients. METHODS: Three groups with 19 patients each were studied. All samples in groups A and B were non-syndromic UCCLP children. Group A was treated with PNAM prior to operation. Group B was untreated prior to operation. Samples in group C were normally developed nose and lip palate infants aged three months. The orthotopic palate photos before and after PNAM treatment for group A, as well as pre-operative photos of groups B and group C, were taken and measured. All statistics were analyzed using SPSS 21.0. RESULTS: PNAM treatment significantly increased the AW, AC, and PA of UCCLP patients (P0.05). CONCLUSION: PNAM treatment is a non-surgical early treatment for the effective improvement of palatal primary deformities in UCCLP patients.

For cool 320×240 detector with staring focal plane array, a long wavelenght infrared continuous zoom optical system was presented. The zoom system is composed of seven lenses and two reflectors. The parameters and schematic of the system ware given by using zoom system principle and optical design software. The image quality and narcissus effect of the system ware analyzed. The system with 8~12μm spectral range can realize 40~240 mm range continuous zoom and fulfil 100% cold shield efficiency.The system has the advantages of simple structure, high image quality, easy adjustion, short zoom journey and smooth zoom locus. Keywords- infrared optical system; continuous zoom; optical design

In this work, pulsed electron deposition was used to prepare thin films of ITO on plastic substrates. These films were used as electrodes for organic photovoltaic devices to determine the feasibility of using PED deposited ITO as electrodes. ITO films deposited on plastic showed optical transmission values as high as 85% for films deposited at high pressures. Films deposited on plastic substrates were further used to prepare a test organic solar cell, with ITO as the bottom electrode. The device performance was seen to depend on the quality of the ITO electrode, and the ITO film deposited at the lowest oxygen pressure was found to be the best electrode for the organic photovoltaic device.