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Conventional photolithography, due to its scalability, robustness, and straightforward processes, has been widely applied to micro- and nanostructure manufacturing in electronics, optics, and biology. However, optical diffraction limits the ultimate resolution of conventional photolithography, which hinders its potential in nanoscale patterning for broader applications. Here, we introduce a derivative of conventional photolithography for nanoscale patterning called dual-layer photolithography (DLPL), which is based on the controlled exposure and development of overlapping positive and negative photoresists. In a typical experiment, substrates are sequentially coated by two layers of photoresists (both positive and negative). Then, we purposefully control the exposure time to generate slightly larger features in the positive photoresist than those in the negative photoresist. After development, their overlapping areas become the final features, which outline the original features. We demonstrate line widths down to 300 nm here, which can be readily improved with more precise control. By adjusting the lithography parameters and material deposition, the feature sizes, shapes (e.g., rings, numbers, letters), line widths (300-900 nm), and materials (e.g., SiO2, Cr, and Ag) of these features can be independently controlled. Combined with anisotropic etching, more complex three-dimensional nanostructures can be fabricated as well, as we demonstrate here with Si. We further fabricate photodetectors as an example application to show that these nanostructures fabricated by DLPL can be used to promote light-trapping MAPbI3 perovskite films to achieve good photoelectric properties. This strategy is not limited to ultraviolet photolithography and may also be incorporated into other energetic beam-based lithographic approaches, including deep and extreme ultraviolet photolithographies and electron beam lithography, to enhance their resolution.

Plasmonic nanostructures have a wide range of applications, including chemical and biological sensing. However, the development of techniques to fabricate submicrometer-sized plasmonic structures over large scales remains challenging. We demonstrate a high-throughput, cost-effective approach to fabricate Au nanoribbons via chemical lift-off lithography (CLL). Commercial HD-DVDs were used as large-area templates for CLL. Transparent glass slides were coated with Au/Ti films and functionalized with self-assembled alkanethiolate monolayers. Monolayers were patterned with lines via CLL. The lifted-off, exposed regions of underlying Au were selectively etched into large-area grating-like patterns (200 nm line width; 400 nm pitch; 60 nm height). After removal of the remaining monolayers, a thin In2O3 layer was deposited and the resulting gratings were used as plasmonic sensors. Distinct features in the extinction spectra varied in their responses to refractive index changes in the solution environment with a maximum bulk sensitivity of ∼510 nm/refractive index unit. Sensitivity to local refractive index changes in the near-field was also achieved, as evidenced by real-time tracking of lipid vesicle or protein adsorption. These findings show how CLL provides a simple and economical means to pattern large-area plasmonic nanostructures for applications in optoelectronics and sensing.

The clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (CRISPR/Cas9) is an efficient and precise gene-editing technology that offers a versatile solution for establishing treatments directed at genetic diseases. Currently, CRISPR/Cas9 delivery into cells relies primarily on viral vectors, which suffer from limitations in packaging capacity and safety concerns. These issues with a nonviral delivery strategy are addressed, where Cas9•sgRNA ribonucleoprotein (RNP) complexes can be encapsulated into supramolecular nanoparticles (SMNP) to form RNP⊂SMNPs, which can then be delivered into targeted cells via supramolecular nanosubstrate-mediated delivery. Utilizing the U87 glioblastoma cell line as a model system, a variety of parameters for cellular-uptake of the RNP-laden nanoparticles are examined. Dose- and time-dependent CRISPR/Cas9-mediated gene disruption is further examined in a green fluorescent protein (GFP)-expressing U87 cell line (GFP-U87). The utility of an optimized SMNP formulation in co-delivering Cas9 protein and two sgRNAs that target deletion of exons 45-55 (708 kb) of the dystrophin gene is demonstrated. Mutations in this region lead to Duchenne muscular dystrophy, a severe genetic muscle wasting disease. Efficient delivery of these gene deletion cargoes is observed in a human cardiomyocyte cell line (AC16), induced pluripotent stem cells, and mesenchymal stem cells.

Wafer-scale nanoribbon field-effect transistor (FET) biosensors fabricated by straightforward top-down processes are demonstrated as sensing platforms with high sensitivity to a broad range of biological targets. Nanoribbons with 350-nm widths (700-nm pitch) were patterned by chemical lift-off lithography using high throughput, low-cost commercial digital versatile disks (DVDs) as masters. Lift-off lithography was also used to pattern ribbons with 2-μm or 20-μm widths (4-μm or 40-μm pitches, respectively) using masters fabricated by photolithography. For all widths, highly aligned, quasi-one-dimensional (1D) ribbon arrays were produced over centimeter length scales by sputtering to deposit 20-nm-thin-film In(2)O(3) as the semiconductor. Compared to 20-μm-wide microribbons, FET sensors with 350-nm wide nanoribbons showed higher sensitivity to pH over a broad range (pH 5 to 10). Nanoribbon FETs functionalized with a serotonin-specific aptamer demonstrated larger responses to equimolar serotonin in high ionic strength buffer compared to microribbon FETs. Field-effect transistors with 350-nm-wide nanoribbons functionalized with single-stranded DNA showed greater sensitivity to detecting complementary DNA hybridization vs 20-μm microribbon FETs. In all, we illustrate facile fabrication and use of large-area, uniform In(2)O(3) nanoribbon FETs for ion, small molecule, and oligonucleotide detection where higher surface-to-volume ratios translate to better detection sensitivities.

Handwritten digit recognition technology refers to the automatic identification of handwritten numbers through computers or other equipment, and it has a greater application prospect in letter postal identification and financial statements and bank bill processing. This paper takes the MNIST handwritten digit database as samples, discusses algorithms KNN, SVM, BP neural network, CNN and their application in handwritten digit recognition. In the training process, this work rewrites KNN with Python, SVM with scikit-learn library, and BP, CNN with Tensorflow, and fine-tunes the algorithm parameters to get the best results for each algorithm. Finally, by comparing the recognition rate and recognition duration of the four algorithms, the advantages and disadvantages of the four algorithms in handwriting recognition are analyzed.

The homology‐independent targeted integration (HITI) strategy enables effective CRISPR/Cas9‐mediated knockin of therapeutic genes in nondividing cells in vivo, promising general therapeutic solutions for treating genetic diseases like X‐linked juvenile retinoschisis. Herein, supramolecular nanoparticle (SMNP) vectors are used for codelivery of two DNA plasmids—CRISPR‐Cas9 genome‐editing system and a therapeutic gene, Retinoschisin 1 (RS1)—enabling clustered regularly interspaced short palindromic repeats (CRISPR)‐associated protein 9 (CRISPR/Cas9) knockin of the RS1 gene with HITI. Through small‐scale combinatorial screenings, two SMNP vectors, with Cas9 and single guide RNA (sgRNA)‐plasmid in one and Donor‐RS1 and green fluorescent protein (GFP)‐plasmid in the other, with optimal delivery performances are identified. These SMNP vectors are then employed for CRISPR/Cas9 knockin of RS1/GFP genes into the mouse Rosa26 safe‐harbor site in vitro and in vivo. The in vivo study involves intravitreally injecting the two SMNP vectors into the mouse eyes, followed by repeated ocular imaging by fundus camera and optical coherence tomography, and pathological and molecular analyses of the harvested retina tissues. Mice ocular organs retain their anatomical integrity, a single‐copy 3.0‐kb RS1/GFP gene is precisely integrated into the Rosa26 site in the retinas, and the integrated RS1/GFP gene is expressed in the retinas, demonstrating CRISPR/Cas9 knockin of RS1/GFP gene., Two supramolecular nanoparticle (SMNP) vectors codeliver two DNA plasmids—a CRISPR‐Cas9 construct and a therapeutic gene, RS1. Both SMNP vectors are intravitreally injected into the eyes of mice to enable CRISPR/Cas9 knockin of the RS1 gene using the homology‐independent targeted integration (HITI) strategy, to test a potential nonviral therapeutic solution for X‐linked juvenile retinoschisis (XLRS).

A variety of nanocarriers have been designed to deliver photosensitizers (PSs) and promote the clinical applications of photodynamic therapy (PDT). However, most of them suffer from insufficient loading capability, premature leakage, and/or unstable therapeutic efficacy. Herein, we constructed a novel nanocomposite (TGP@MOS) with a benzene-bridged mesoporous organosilica shell and a triangular gold nanoprism core. The TGP@MOS could load model PS molecules, zinc phthalocyanine (ZnPc), with high loading capacity (11.8 wt%) and minimal premature leakage (only 2.6% after incubation in PBS with 10% FBS for 60 h) via π–π stacking interactions and hydrophobic interactions. We demonstrated that the obtained TGP@MOS–ZnPc could realize timely coordinated photodynamic/photothermal therapy upon single irradiation, and thus stabilize and maximize the therapeutic efficacy of phototherapy both in vitro and in vivo. Other advantages of TGP@MOS-ZnPc include excellent water solubility, stability, hemocompatibility and biocompatibility.

Consuming arsenic (As)-contaminated vegetables is the main route of As exposure in humans. The present study focused on the alterations in antioxidant enzymatic activities and As bioaccessibility in As-contaminated radish subjected to Se. Compared to the CK group, the total As content in raw radish was reduced by 27.5 ± 1.3%, and the bioaccessibility of As was reduced by 21.9 ± 2.3% in the 6 mg Se kg−1 treatment group. The total As content in the treatment groups decreased first but then increased with increasing Se application in raw radish, gastric (G) fraction and gastrointestinal (GI) fraction, while the antioxidant activity exhibited the opposite trend. The results revealed that a low amount of Se effectively blocks the accumulation of As in radish, improves the antioxidant activity in radish and reduces the bioaccessibility of As. These findings provide new ideas for effectively alleviating the spread of As to the human body through the food chain.

A major source of uncertainty in civil engineering projects arises from the geological and geotechnical variability at the project site. This paper presents an approach to quantify such uncertainty, and to rationally incorporate them into estimates of cost contingency. Contrary to the conventional approaches that rely on individual expert's opinion or data from past projects, the proposed approach allows site-specific assessments of the intrinsic geotechnical variability through geostatistical techniques. Such uncertainty can be reduced through geotechnical investigation, and spatial tessellation techniques are proposed to facilitate determination of the optimal locations of new boreholes. Cost-effectiveness of the boreholes can be evaluated based on the corresponding reductions in geotechnical uncertainty and their influence on the budget. The approach is illustrated using a hypothetical excavation scenario, where the project costs are affected by uncertainty in the subsurface strata, particularly the rockhead level across the site. Under the specific site conditions, a Pareto frontier is developed to reveal the relationship between the number of boreholes to be drilled and potential savings in contingency budget. Through this approach, the study promotes better utilization of geotechnical information and rational assessments of project risks associated with their variability, which may lead to improved project planning and resource allocation.

Non-small cell lung cancer (NSCLC) is difficult to cure because of the high recurrence rate and the side effects of current treatments. It is urgent to develop a new treatment that is safer and more effective than current treatments against NSCLC. Herein, we constructed anti-epidermal growth factor receptor (EGFR) peptide-conjugated PEGylated triangular gold nanoplates (TGN-PEG-P75) as a targeting photothermal therapy (PTT) agent to treat NSCLC under the guidance of computed tomography (CT) and photoacoustic (PA) imaging. The surface of TGNs is successfully conjugated with a novel peptide P75 that has the specific affinity to epidermal growth factor receptor (EGFR). It is found that the EGFR is overexpressed in NSCLC cells. The TGN-PEG-P75 has uniform edge length (77.9 ± 7.0 nm) and neutrally charged surface. The cell uptake experiments demonstrate remarkable affinity of the TGN-PEG-P75 to high EGFR expression cells than low EGFR expression cells (5.1-fold). Thanks to the strong near-infrared absorbance, high photothermal conversion efficiency, and the increased accumulation in tumor cells via the interaction of P75 and EGFR, TGN-PEG-P75 exhibits 3.8-fold superior therapeutic efficacy on HCC827 cells than TGN-PEG. The in vivo CT/PA dual-modal imaging of the TGN-PEG-P75 is helpful in selecting the optimal treatment time and providing real-time visual guidance of PTT. Furthermore, treatments on HCC827 tumor-bearing mouse model demonstrate that the growth of NSCLC cells can be effectively inhibited by the TGN-PEG-P75 through PTT, indicating the great promise of the nanoplatform for treating NSCLC in vivo.

Physical layer security is a crucial issue in wireless networks to prevent legitimate communication from eavesdropping. This paper investigates the physical layer security of a wireless multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) communication system in the presence of a multiple-antenna eavesdropper. We first propose a minimum mean square error (MMSE)-based-filter secure MIMO–OFDM system which can destroy the orthogonality of eavesdropper’s signals. The MMSE-based-filter is used at the receiver to suppress the inter-subcarrier interference and disturb the reception of eavesdropper while maintaining the quality of legitimate transmission. Next, we propose another artificial noise (AN)-assisted secure MIMO–OFDM system to further improve the security of the legitimate transmission. The time-domain AN signal is designed to be canceled out at the legitimate receiver. Therefore, AN will disturb the reception of eavesdropper while the legitimate transmission will not be affected. Finally, power allocation for AN signals and subcarriers will be discussed since AN is generated utilizing the residual power of the MIMO–OFDM system. Simulation results are presented to demonstrate the security performance of the proposed transmit filter design and AN-assisted scheme in the MIMO–OFDM system.

Enhancing the tumor-targeting delivery of chemotherapeutic drugs is important yet challenging for improving therapeutic efficacy and reducing the side effects. Here, we first construct a drug delivery system for targeting tumor acidic microenvironment by modification of pH (low) insertion peptide (pHLIP) on mesoporous organosilica nanoparticles (MONs). The MONs has thioether-bridged framework, uniform diameter (60 nm), good biocompatibility, and high doxorubicin (DOX) loading capacity (334 mg/g). The DOX loaded in the pHLIP modified MONs can be released responsive to glutathione and low pH circumstance, ensuring the chemotherapeutic drug exerts higher cytotoxic effects to cancer cells than normal cells because of high intracellular GSH of tumor cells and low pH of tumor microenvironment. Moreover, the engineered MONs exhibit higher cellular uptake in pH 6.5 medium by MDA-MB-231 and MCF-7 cells than the particles decorated with polyethylene glycol (PEG). Importantly, the pHLIP-mosaic MONs with DOX displays better cytotoxic effects against the breast cancer cells in pH 6.5 medium than pH 7.4 medium. The in vivo experiments demonstrate that the pHLIP modified MONs are accumulated in the orthotopic breast cancer via targeting to acidic tumor microenvironment while no serious pathogenic effects was observed. After loading DOX, the pHLIP-modified MONs display better therapeutic effects than the control groups on the growth of MCF-7 breast cancers, showing promise for enhancing chemotherapy.

To date, clinicians still lack an effective strategy to treat triple negative breast cancer (TNBC). In this work, we design for the first time a gold nanorod embedded large-pore mesoporous organosilica (GNR@LPMO) nanoplatform for gene and photothermal cooperative therapy of TNBC. The synthesized GNR@LPMOs possess a uniform size (175 nm), high surface area (631 m2 g−1), large pore size, excellent photothermal efficiency, and good biocompatibility. Thanks to the large-pore mesoporous organosilica layer, the GNR@LPMO nanoplatforms display much higher loading capacity of siRNA compared with traditional liposome and bare gold nanorods. Thus, functional siRNA can be efficiently delivered into TNBC cells by GNR@LPMOs, causing much higher cell apoptosis through knocking down the PLK1 proteins. By combining the effective gene delivery and photothermal abilities, the GNR@LPMO nanoplatforms are further used for gene and photothermal cooperative therapy of TNBC, which induce a 15 fold higher mice tumor inhibition rate than sole therapy modality, indicating the potential clinical use of this novel nanoplatform in treating TNBC.

Despite recent efforts to characterize the uncertainties involved with geological profiles and soil and rock properties, there has been limited study on their spatial correlations and how such features may be included in the engineering decision-making process. This paper presents an integrated framework for geostatisical analyses, which incorporates the restricted maximum likelihood (REML) method with the Matérn autocovariance model. Statistical tests are conducted including those for data normality, constant variance, and outliers, which ensure the fundamental assumptions of REML are not violated in the residual analyses of site data, meanwhile offering simple checks for potential errors in the dataset. The proposed approach also allows quantification of uncertainties in the subsurface profiles at the unsampled locations. The approach is illustrated through investigations on spatial correlation features of geological profiles at two project sites in Hong Kong. The number of irregularly spaced boreholes varies from 150 to 350 in the two cases, and the large volume of data enables the variations in rockhead levels to be studied through the proposed framework. In addition, the existence of geological faults in one of the sites is found to significantly affect the spatial variability of the rockhead level, as indicated by the reduced scales of fluctuation and spatial dependence, which corresponds to increased uncertainty in areas intersected by faults.

Multifunctional nanoagents, in particular those that combine diverse diagnostic and therapeutic functions, have attracted great enthusiasm in oncotherapy. In this work, a triangular gold nanoprism decorated with gadopentetic acid (Gd–DTPA) (TGP–PEG–Gd) was constructed for use in cancer theranostics. TGP–PEG–Gd exhibits uniform morphology, excellent monodispersity and near infrared absorbance properties. The magnetic properties of gadolinium, together with the X-ray attenuation of gold, enable TGP–PEG–Gd to be employed for T1-weighted MR/CT dual-modality imaging. The longitudinal relaxivity (r1) of TGP–PEG–Gd was calculated to be 23.1 mM−1 s−1, and its X-ray absorption coefficient was 959.3 HU L g−1. In addition, TGP–PEG–Gd possesses effective photothermal conversion ability, which was utilized for successful photothermal therapy. Moreover, the excellent biocompatibility of TGP–PEG–Gd was proved both in vitro and in vivo. Biocompatible TGP–PEG–Gd may hold promise for the photothermal therapy of cancers guided by MR/CT dual-modality imaging.

Understanding hydrological responses to reforestation is an important subject in watershed management, particularly in large forested watersheds ( > 1000 km2). In this study, we selected two large forested watersheds (Pingjiang and Xiangshui) located in the upper reach of the Poyang Lake watershed, southeastern China (with an area of 3261.4 and 1458 km2, respectively), along with long-term data on climate and hydrology (1954–2006) to assess the effects of large-scale reforestation on streamflow. Both watersheds have similar climate and experienced comparable and dramatic forest changes during the past decades, but with different watershed properties (e.g., the topography is much steeper in Xiangshui than in Pingjiang), which provides us with a unique opportunity to compare the differences in hydrological recovery in two contrasted watersheds. Streamflow at different percentiles (e.g., 5, 10, 50 and 95 %) were compared using a combination of statistical analysis with a year-wise method for each watershed. The results showed that forest recovery had no significant effects on median flows (Q50%) in both watersheds. However, reforestation significantly reduced high flows in Pingjiang, but had limited influence in Xiangshui. Similarly, reforestation had significant and positive effects on low flows (Q95%) in Pingjiang, while it did not significantly change low flows in Xiangshui. Thus, hydrological recovery is limited and slower in the steeper Xiangshui watershed, highlighting that watershed properties are also important for determining hydrological responses to reforestation. This finding has important implications for designing reforestation and watershed management strategies in the context of hydrological recovery.

Porous carbon are excellent electrode materials for energy-storage devices. Here, we present a facile in-situ reduction method to improve the electrochemical performance of carbon materials by gold nanoparticles. The prepared porous carbon microspheres decorated with gold-nanoparticle had a 3D honeycomb-like structure with a high specific surface area of about 1635 m2 g−1, confirmed by scanning electron microscopy, transmission electron microscopy, and the Brunauer-Emmett-Teller method. The electrochemical performance of as-synthesized porous carbon microspheres was exemplified as electrode materials for supercapacitor with a high specific capacitance of 440 F g−1 at a current density of 0.5 A g−1, and excellent cycling stability with a capacitance retention of 100% after 2000 cycles at 10 A g−1 in 6 M KOH electrolyte. Our method opened a new direction for the gold-nanoparticle-decorated synthesis of porous carbon microspheres and could be further applied to synthesize porous carbon microspheres with various nanoparticle decorations for numerous applications as energy storage devices, enhanced absorption materials, and catalytical sites.

Fruit tree planting is a common practice for alleviating poverty and restoring degraded environment in developing countries. Yet, its environmental effects are rarely assessed. The Jiujushui watershed (261.4 km2), located in the subtropical Jiangxi Province of China, was selected to assess responses of several flow regime components on both reforestation and fruit tree planting. Three periods of forest changes, including a reference (1961 to 1985), reforestation (1986 to 2000) and fruit tree planting (2001 to 2016) were identified for assessment. Results suggest that the reforestation significantly decreased the average magnitude of high flow by 8.78%, and shortened high flow duration by 2.2 days compared with the reference. In contrast, fruit tree planting significantly increased the average magnitude of high flow by 27.43%. For low flows, reforestation significantly increased the average magnitude by 46.38%, and shortened low flow duration by 8.8 days, while the fruit tree planting had no significant impact on any flow regime components of low flows. We conclude that reforestation had positive impacts on high and low flows, while to our surprise, fruit tree planting had negative effects on high flows, suggesting that large areas of fruit tree planting may potentially become an important driver for some negative hydrological effects in our study area.

In Content-Centric network (CCN), the capacity of router nodes caches the contents to satisfy the requests from subsequent consumers, and reduce the network overhead. Considering the limited cache capacity, the update of cached contents becomes a key element affecting the caching performance for the future 6G network. In this paper, a replacement strategy based content popularity and cache gain (PGR) is proposed for 6G-CCN. In the proposed scheme, the popularity of contents in the current cycle is determined according to the time interval and frequency of consumers’ requests. In addition, the distance between the router node and consumer affects the gain of caching. Further considering the dynamic popularity of content and gain of caching, a realistic content value function is provided. When the cache space reaches the upper bound, for the router node, the existing content with lower value will be replaced by newly arrived content with a higher value. Simulation results show that, compared with the conventional least frequently used (LFU) and least recently used (LRU), the proposed replacement strategy can effectively improve the space utilization and cache hit rate of router nodes, as well as reduce the average hops of consumers’ content acquisition for 6G-CCN.

This letter investigates the problem of blind detection of orthogonal space-time block codes (OSTBC) over a quasi-static flat multiple-input multiple-output (MIMO) Rayleigh fading channel. We first introduce a core iterative least-squares (ILS) algorithm to blindly detect OSTBC signals without the knowledge of channel state information (SCI) at the receiver. This ILS algorithm has low computational complexity but may converge to local optimum which offers unreliable detection result. Then, in order to improve the detection performance, we propose an enhanced ILS (E-ILS) approach which is based on statistical analysis of repeated independent ILS procedures on received data. Extensive simulation studies prove the efficiency of the proposed E-ILS algorithm with blind detection performance approaching the optimal maximum-likelihood detector with known CSI., Submitted to IEEE Wireless Communications Letters

Fruit tree planting is often considered as one of reforestation practices in the past decades in many parts of China because it increases forest coverage while gaining short-term economic benefits. However, the effects of large-scale fruit tree planting on water resources at the watershed scale are rarely assessed, especially in subtropical China. In this study, the forested watershed (Jiujushui watershed, 261.4 km2), located in Southeastern China, was selected to examine the responses of major flow components including baseflow, surface runoff, and total streamflow to both reforestation (e.g., Cunninghamia lanceolata (Lamb.) Hook and Pinus massoniana Lamb.) and fruit tree planting (e.g., Citrus reticulate Blanco) practices. The study period (1961–2016) was split into three sub-periods including reference, reforestation and fruit tree planting. The combined approach including pair-wise method and separation of relative contributions was adopted in this study. The former was used to test the statistical relations between forest changes and flow components, while the latter (sensitivity-based and time trend methods) was applied to quantitatively separate the relative contributions of forest changes and climatic variability to each flow component so that the effects of forest changes (reforestation and fruit tree planting) on flow components can be quantified and compared. Results from the pair-wise technique showed that reforestation and fruit tree planting had no significant effects on total streamflow. However, reforestation significantly increased base flow by 15% (p = 0.03), while fruit tree planting did not. In contrast, surface runoff was significantly increased by fruit tree planting (p = 0.048), while it was not by reforestation. The results from the separation technique showed that in the reforestation period, the relative contributions of reforestation to surface runoff, baseflow and total streamflow were 23.9%, 67.3% and 50.9%, respectively, in comparison with 76.1%, 32.7% and 49.1% from climate variability, highlighting that reforestation had greater effects on base flow. However, fruit tree planting accounted for 54.4%, 48.8% and 57.3% of total streamflow, baseflow and surface runoff variations, while climatic variability were responsible for 45.6%, 51.3% and 42.7%, respectively in the fruit tree planting period, demonstrating that fruit tree planting had greater effects on surface runoff. Thus, the results from both techniques clearly demonstrated that forest recovery through reforestation effectively increased baseflow, while fruit tree planting caused increasing of surface runoff. We also conclude that the combination approach provides a robust and complementary research framework for assessing the hydrological effects of reforestation in a single watershed.

Recently, researchers were interesting in exploring alternative materials for well-studied CdZnTe which was the key material of radiation detection. Cadmium Magnesium Telluride (Cd1-xMgxTe) crystal was regarded as promising one for room temperature X-ray and gamma-ray detectors due to some potential advantages. In this paper, two large-size Cd0.95Mg0.05Te ingots with 30 mm diameter and over 100 mm length were successfully grown by a modified vertical Bridgman method. Two modifications, including Cd excess or Te-rich condition and the accelerated crucible rotation technique (ACRT), were applied in growing process to decrease defects, enhance resistivity and homogenize component distribution. The results indicated that both ingots had a cubic zinc-blende structure. The distribution of Mg element in the ingots along axial direction was very homogeneous. The energy band gap of Cd0.95Mg0.05Te was close to Cd0.9Zn0.1Te. Low density of Te inclusions (103 cm−3 order of magnitudes) and high IR transmittance (over 60%) showed the good crystal quality. Raman scattering spectroscopy also showed a good crystal quality for Cd0.95Mg0.05Te crystals. Thus, Cd0.95Mg0.05Te crystals could be a promising radiation detector material.

Nanoribbon- and nanowire-based field-effect transistors (FETs) have attracted significant attention due to their high surface-to-volume ratios, which make them effective as chemical and biological sensors. However, the conventional nanofabrication of these devices is challenging and costly, posing a major barrier to widespread use. We report a high-throughput approach for producing arrays of ultrathin (∼3 nm) In2O3 nanoribbon FETs at the wafer scale. Uniform films of semiconducting In2O3 were prepared on Si/SiO2 surfaces via a sol-gel process prior to depositing Au/Ti metal layers. Commercially available high-definition digital versatile discs were employed as low-cost, large-area templates to prepare polymeric stamps for chemical lift-off lithography, which selectively removed molecules from self-assembled monolayers functionalizing the outermost Au surfaces. Nanoscale chemical patterns, consisting of one-dimensional lines (200 nm wide and 400 nm pitch) extending over centimeter length scales, were etched into the metal layers using the remaining monolayer regions as resists. Subsequent etch processes transferred the patterns into the underlying In2O3 films before the removal of the protective organic and metal coatings, revealing large-area nanoribbon arrays. We employed nanoribbons in semiconducting FET channels, achieving current on-to-off ratios over 107 and carrier mobilities up to 13.7 cm2 V-1 s-1. Nanofabricated structures, such as In2O3 nanoribbons and others, will be useful in nanoelectronics and biosensors. The technique demonstrated here will enable these applications and expand low-cost, large-area patterning strategies to enable a variety of materials and design geometries in nanoelectronics.

Photodynamic therapy (PDT) has attracted much attention as a strategy for tumor therapy. However, the insolubility and poor tumor-targeting ability of most photosensitizers (PSs) hinder PDT from further development. Therefore, it is necessary to explore new carriers with good water solubility and biocompatibility to deliver PSs to tumors. Melanin nanoparticles are novel biomimetic nanocarriers with excellent biocompatibility, loading capacity, photothermal therapy (PTT) and magnetic resonance (MR)/photoacoustic (PA) imaging properties. Here we designed polydopamine melanin nanoparticles (PDMNs) as a delivery platform for the photosensitizer Chlorin e6 (PDMN–Ce6) and realized its application as a theranostic agent for tumor therapy. The PDMN–Ce6 exhibited excellent biocompatibility, good water solubility and high loading capability (35.2 wt%) for Ce6. Compared with the free Ce6, PDMN–Ce6 showed higher cellular internalization and superior synergistic phototherapy effects in an in vitro study. An in vivo study indicated that the accumulation of PDMN–Ce6 at tumor sites was 2.8-fold higher than that of free Ce6 at 24 h post-injection, which was beneficial for MR/PA imaging. Moreover, the synergetic therapy significantly inhibited tumor growth, causing tumor necrosis and tumor angiogenesis suppression. These results suggest that our biomimetic and biocompatible platform could improve the delivery of Ce6 to tumors and realize multimodal imaging-guided tumor synergetic phototherapy.

Adjuvant treatments following breast-conserving surgery (BCS) are essential to reduce the risk of local recurrences in patients with breast cancer. However, current adjuvant treatments are based on ionizing radiation, which brings radiation-induced damage and amplifies the risk of death. Here we explore the feasibility of using non-ionizing light to induce photothermal therapy as an adjuvant treatment to BCS. In an orthotopic breast cancer mice model, we demonstrate that adjuvant photothermal therapy (aPTT) decreases the incidence of local recurrences after BCS with no expense of cosmetic outcome. In comparison with conventional photothermal therapy, the technique used in aPTT provides more uniformly distributed light energy and less risk of skin burns and local recurrences. Overall, this work represents a departure from the traditional concept of using PTT as an alternative to surgery and reveals the potential of using PTT as an alternative to adjuvant radiation therapy, which is valuable especially for patients susceptible to radiation damage.

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer. It is known that hyaluronic acid (HA) binds CD44 receptors, which are overexpressed on the surface of TNBC cells. To optimize the targeting ability of HA, in this study we coated gold nanobipyramids (GBPs) with high and low molecular weight HA (380 kDa and 102 kDa), named GBPs@h-HA and GBPs@l-HA, respectively. GBPs@l-HA and GBPs@h-HA had excellent stability when dispersed in water and PBS (pH 7.4) for seven days. The HA density was calculated by the ratio of HA to GBPs@l-HA and GBPs@h-HA, which was 13.22 and 4.77, respectively. The two nanoparticles displayed good photostability, which was evaluated by their photothermal performance and similar biocompatibility. Inductively coupled plasma atomic emission spectrometry (ICP-AES) revealed superior cellular uptake of GBPs@h-HA over GBPs@l-HA. Upon 808 nm laser irradiation, the GBPs@h-HA also showed higher therapeutic efficacy than GBPs@l-HA both in vitro and in vivo. Overall, our study demonstrates that the molecular weight of HA plays an important role in the targeting ability and thus photothermal therapeutic efficacy of HA-coated gold nanobipyramids.

Herein, a mesoporous organosilica nanoparticle (MON) based nanodrug highly loaded with cisplatin (CDDP) and doxorubicin (DOX) (denoted as MONs/CDDP/DOX) has been successfully prepared for the first time. The MONs are characterized with core-contained double hollow shells, thioether and ethane groups separately incorporated frameworks, uniform diameter (420 nm), large surface area (592 m2/g), and ordered pore size (2.5 nm). The safety evaluation of the MONs based on cell viability, haemolytic activity, histological change, and serum biochemical index demonstrates that they have excellent biological compatibility. The efficient uptake of the MONs by human breast cancer MCF-7 cells is further confirmed via confocal laser scanning imaging and flow cytometry. Importantly, the contents of CDDP and DOX in the MONs/CDDP/DOX nanodrug are as high as 120 mg/g and 85 mg/g, respectively. Therefore, the MONs/CDDP/DOX shows a significant improved killing effect against human breast cancer MCF-7 cells compared with sole DOX or CDDP loaded MONs, demonstating the promise of the nanodrug for cancer treatment.

This paper investigates the problem of hybrid precoder and combiner design for multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems operating in millimeter-wave (mmWave) bands. We propose a novel iterative scheme to design the codebook-based analog precoder and combiner in forward and reverse channels. During each iteration, we apply compressive sensing (CS) technology to efficiently estimate the equivalent MIMO-OFDM mmWave channel. Then, the analog precoder or combiner is obtained based on the orthogonal matching pursuit (OMP) algorithm to alleviate the interference between different data streams as well as maximize the spectral efficiency. The digital precoder and combiner are finally obtained based on the effective baseband channel to further enhance the spectral efficiency. Simulation results demonstrate the proposed iterative hybrid precoder and combiner algorithm has significant performance advantages.

Forested catchments provide critically important water resources. Due to dramatic global forest change over the past decades, the importance of including forest or vegetation change in the assessment of water resources under climate change has been highly recognized by Intergovernmental Panel on Climate Change (IPCC); however, this importance has not yet been examined quantitatively across the globe. Here, we used four remote sensing-based indices to represent changes in vegetation cover in forest dominated regions, and then applied them to widely-used models: the Fuh model and the Choudhury-Yang model to assess relative contributions of vegetation and climate changes to annual runoff variations from 2000 to 2011 in forested landscape (forest coverage > 30%) across the globe. Our simulations show that the global average variation in annual runoff due to change in vegetation cover is 30.7 ± 22.5% with the rest attributed to climate change. Large annual runoff variation in response to vegetation change are found in tropical and boreal forests due to greater forest losses. Our simulations also demonstrate both offsetting and additive effects of vegetation cover and climate in determining water resource change. We conclude that vegetation cover change must be included in any global models for assessing global water resource change under climate change in forest-dominant areas. This article is protected by copyright. All rights reserved.

The combination of hyperthermia and chemotherapy is able to greatly enhance the treatment efficacy mainly due to the synergistic interactions between these two treatments. In this study, we propose a new concept of mild hyperthermia enhanced chemotherapy to explore and validate the synergistic mechanism in vitro and in vivo. To do this, a novel kind of biodegradable nanotheranostics based on copper sulfide doped periodic mesoporous organosilica nanoparticles (CuS@PMOs) was constructed via an in situ growth method for light-triggered mild hyperthermia and drug delivery. The as-prepared CuS@PMOs exhibit a high doxorubicin (DOX) loading capacity of 470 mg/g. The DOX release from CuS@PMOs can be precisely controlled by three stimuli, including intracellular glutathione (GSH), acidic environment in tumor cells, and external laser irradiation. Most intriguingly, mild hyperthermia induced by laser-irradiated CuS nanoparticles can dramatically improve the cell uptake of nanotheranostics both in vitro and in vivo, thus significantly enhancing the chemotherapeutic efficacy for complete tumor growth suppression without recurrence. Meanwhile, the fluorescence recovery following the DOX release can be used as an indicator to monitor the chemotherapeutic progress.

Nanomaterial-based immunotherapy stimulating T cell activation or tumor-associated macrophage (TAM) conversion holds great promise for promoting tumor suppression. Herein, a novel nanoplatform, iron oxide-embedded large-pore mesoporous organosilica nanospheres (IO-LPMONs), is prepared for the first time to simultaneously activate cytotoxic T cells and polarize macrophages for potent tumor immunotherapy. The IO-LPMONs have large mesopores (6.3 nm) and inorganic-organic hybrid shells, which contribute to a high payload (500 µg mg-1 ) of the antigen ovalbumin (OVA). The IO-LPMONs effectively deliver OVA to dendritic cells (DCs) and activate DCs. Subsequently, high activation of both CD4+ and CD8+ effector antigen-specific T cells is achieved for powerful antitumor effects. Moreover, the IO-LPMONs also act as an immune modulator to polarize TAMs from an immunosuppressive M2 to a tumor-killing M1 phenotype, which induces efficient apoptosis of tumor cells. The combined T cell activation and macrophage polarization strategy based on the IO-LPMONs elicits remarkable combined antitumor effects in vivo, showing great promise for tumor treatment.

The “Regulation on the Emergency Response, Investigation and Handling of Electric Power Security Accidents”, based on load-shedding proportion, namely the Decree No.599 of the State Council of the People's Republic of China, was implemented on September 1st, 2011, which proposed new more stringent requests for power system reliability and security. Combining with related regulations on the Decree No.599, in this paper a new anticipated fault sets selection method which considers influences of electromagnetic loop networks for power grid reliability are proposed, the model of load-shedding allocating among fault substations is built, the algorithm of electricity security accidents risk grade assessment is designed. On the basis of that, taking an actual power grid as an example, simulation results can reflect electricity security accidents from perspective of probability and severity and shall distinguish weaknesses of the power grid effectively.

The pilot spoofing attack is considered as an active eavesdropping activity launched by an adversary during the reverse channel training phase. By transmitting the identical pilot signal as that of the legitimate user, the pilot spoofing attack can degrade legitimate transmission and, more severely, facilitate eavesdropping. This paper considers the problem of detecting pilot spoofing attack for a typical multi-input single-output (MISO) wiretap system. We slightly modify the conventional training mechanism and divide the procedure into pilot phase and random phase. By examining the difference of estimated legitimate channels during these two phases, a novel random-training-aided (RTA) detection algorithm is proposed to identify the existence of the pilot spoofing attack. Extensive simulation results illustrate that our proposed RTA scheme can achieve accurate pilot spoofing detection.

This paper considers the problem of physical layer security of a wireless orthogonal frequency division multiplexing (OFDM) communication system. We first develop a transmit filter-aided secure OFDM system scheme which can disturb eavesdropper's receptions by destroying the orthogonality of OFDM signals at the eavesdropper, while the quality of legitimate transmission is maintained. Then, in an effort to further improve the security performance, we also propose an artificial noise (AN)-aided secure OFDM system associated with the transmit filter-aided approach. AN is generated in the null space of the legitimate channel by making use of residual power after power allocation for subcarriers. Therefore, AN can only disrupt eavesdropper's receptions but not affect legitimate receiver. Simulation results are presented to illustrate the efficiency of the proposed transmit filter and AN-aided physical layer security designs in the OFDM wiretap system.

Combining actual demands for ultra-high voltage (UHV) power grid of our country electricity production, power collection, electricity transmission and distribution, functions, adequacy and reliability of different UHV power grid projection are discussed in this paper. They were discussed that differences in function and reliability of different UHV power grid structure, and the development necessity, feasibility and rationality of UHV AC/DC power grid in China. Power supply capacity adequacy and security of different power grid were discussed complementally in the aspect of system reliability. It is shown that the UHV AC/DC transmission grid with strong frame is superior relatively to meet the performance of transmission demand in China. In terms of system security complexity, cascading failure conditions and the complexity of power system blackouts were expounded. It is pointed out that the defect of power system security defense system is an important reason leading to large scale power system blackout. While constructing the UHV AC/DC power grid, it is necessary to establish a new generation of power system security monitoring system to improve the security and defense system of large-scale power grid.

Complete eradication of highly aggressive triple negative breast cancer (TNBC) remains a notable challenge today. In this work, an imaging-guided photothermal-chemotherapy strategy for TNBC is developed for the first time based on a periodic mesoporous organosilica (PMO) coated Prussian blue (PB@PMO) nanoplatform. The PB@PMOs have organic-inorganic hybrid frameworks, uniform diameter (125 nm), high surface area (866 m2 g-1), large pore size (3.2 nm), excellent photothermal conversion capability, high drug loading capacity (260 µg mg-1), and magnetic resonance (MR) and photoacoustic (PA) imaging abilities. The MR and PA properties of the PB@PMOs are helpful for imaging the tumor and showing the accumulation of the nanoplatform in the tumor region. The bioluminescence intensity and tumor volume of the MDA-MB-231-Luc tumor-bearing mouse model demonstrate that TNBC can be effectively inhibited by the combined photothermal-chemotherapy than monotherapy strategy. Histopathological analysis further reveals that the combination therapy results in most extensive apoptotic and necrotic cells in the tumor without inducing obvious side effect to major organs.

Assessing how forest disturbance and climate change affect baseflow or groundwater discharge is critical for understanding water resource supply and protecting aquatic functions. Previous studies have mainly evaluated the effects of forest disturbance on streamflow, with rare attention on baseflow, particularly in large watersheds. However, studying this topic is challenging as it requires explicit inclusion of climate into assessment due to their interactions at any large watersheds. In this study, we used Upper Similkameen River watershed (USR) (1810 km2), located in the southern interior of British Columbia, Canada to examine how forest disturbance and climate variability affect baseflow. The conductivity mass balance method was first used for baseflow separation, and the modified double mass curves were then employed to quantitatively separate the relative contributions of forest disturbance and climate variability to annual baseflow. Our results showed that average annual baseflow and baseflow index (baseflow/streamflow) were about 85.2 ± 21.5 mm year-1 and 0.22 ± 0.05 for the study period of 1954–2013, respectively. The forest disturbance increased the annual baseflow of 18.4 mm, while climate variability decreased 19.4 mm. In addition, forest disturbance also shifted the baseflow regime with increasing of the spring baseflow and decreasing of the summer baseflow. We conclude that forest disturbance significantly altered the baseflow magnitudes and patterns, and its role in annual baseflow was equal to that caused by climate variability in the study watershed despite their opposite changing directions. The implications of our results are discussed in the context of future forest disturbance (or land cover changes) and climate changes.

The effects of forest cover change on water yield have long been studied across the globe. Several reviews have summarized the impacts of forest change and water yield from the small and paired watershed experiments, but no any synthetic assessment has been conducted on the basis of studies of large watersheds (>1,000 km2). We conducted a synthetic analysis on the basis of the studies from 162 large studied watersheds across the globe to explore how forest cover change affects annual water yield. Our first-ever assessment confirms that deforestation increases annual water yield and reforestation decreases it, which is consistent with results from paired watershed experiments. More importantly, we found that forest cover and climate variability play a coequal role in annual water yield variations. The effects of forest cover change and climate variability on annual water yield variations can be additive or offsetting. Thus, their interactions can critically determine the magnitudes and directions of water yield changes. We also found that the hydrological sensitivities to forest cover change in smaller and dryer watersheds are higher than those in larger and wetter ones. The implications of these findings for sustainable water and watershed management are discussed in the context of future land cover and climate changes.