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To curb the increasing pollutant emissions that have accompanied rapid economic growth, China implemented a mandatory emissions control system since the 11th Five-Year Plan (FYP) period, and the emission reduction targets have been met and even exceeded. This article explores how China achieved its emissions reduction targets by systematically identifying the main emission reduction pathways, including both the environmental and economic factors, and evaluates the contribution of each factor using structure decomposition analysis. A study of the two key controlled pollutants, industrial sulfur dioxide (SO2) and chemical oxygen demand (COD), during the 11th FYP period showed that (i) changes in the end-of-pipe treatment and pollutant generation coefficient were the dominant contributors to emissions reduction. The power and metal smelting sectors played important roles in SO2 abatement, while the paper products and food products sectors were important in COD reduction; (ii) changes to the input coefficient increased overall emissions although there was a decrease in SO2 emissions in 2007-2010 mainly due to input structure improvements in the construction sector; (iii) the trade effect largely offset the domestic emission reduction effects, although the trade effect declined during the study period; (iv) domestic demand was the main factor increasing domestic emissions; domestic investment changes (especially in the construction sector) were the major contributor to increases in SO2 emissions, and final consumption changes (especially consumption in the food production sector) were the main contributor to the increase in COD emissions. The results yield important implications for China's pollution emissions control policies.

To explore the feasibility of utilizing recycled aggregate concrete (RAC) in revetment construction of the lower Yellow River, a series of mix proportions with local recycled aggregates (RA) were designed to evaluate its mechanical properties and durability. The morphology and micro-hardness of the interface transition zone (ITZ) were also characterized to explain the performance of RAC. Based on the compressive strength data of 13 groups of mixtures, which is larger than 30 MPa, and with the RA substitution rate not less than 50%, the RAC containing 50% recycled fine aggregate (RFA) (HDX50), 70% RFA (HDX70), and 50% recycled coarse aggregate (RCA) (HDC50) were selected. The experiment results suggest that the mechanical performance, frost resistance, and carbonation resistance of the selected RAC is generally poorer than that of natural aggregate concrete (NAC), but can meet the performance requirement of concrete for the revetment construction of the lower Yellow River. The comprehensive performance of these three mixtures ranks as: HDX50 &gt, HDX70 &gt, HDC50. When considering the RA substitution ratio as a priority, HDX70 would be the best choice and can be applied in the revetment engineering. A number of defects are observed on the surface of RA with old pastes attached. Furthermore, the ITZs formed around RA are loose and with low micro-hardness, which is deemed to be the dominating reasons leading to the weaker performance of RAC than that of NAC.

Metabolism is often regulated by the transcription and translation of RNA. In turn, it is likely that some metabolites regulate enzymes controlling reversible RNA modification, such as N

City-level carbon footprint has been recognized as a useful measure of anthropogenic impact on climate change associated with citizens' activities within the administrative boundary. Although the promotion of consumer responsibility suggests rethinking urban indirect emissions, the detailed methodology is far from satisfactory for realistic applications. Due to the lack of multi-regional input-output tables for most cities, there is a wide application of single regional input-output tables. However, there still lacks further discussion on if there will be an obvious evaluation bias by applying city-level single-regional tables rather than multi-regional ones. To visualize the table coverage on its application consequence, both single- and multi-regional input-output tables were employed to compare disparities in the carbon footprint accounting in the case of Tokyo, Japan. Our analysis shows that the gap of emissions driven by Tokyo's final demand between single- and multi-regional input-output tables was considerably large. Furthermore, the results of multi-regional table were found to be 8.11 MtC higher for coal-generated emissions, 7.83 MtC for crude oil-generated emissions and 2.90 MtC for natural gas-generated emissions than those of the single-regional table. The largest deviation in emissions accounting was observed in the power, gas and heating supply sector, the construction sector and the private service sector. The gap between these two input-output tables was notable for all three types of fossil fuels (coal, crude oil and natural gas). These indicated that coal-generated emissions have been largely ignored by single-regional input-output table. The study highlighted the difference of carbon footprint accounting between these two types of input-output tables. Our findings are intended to assist policymakers and scholars in pinpointing and reallocating sectors that are likely to yield severely biased evaluation of emissions embodied in trade when a multi-regional table is not available.

Membrane vesicles derived from live cells show great potential in biological applications due to their preserved cell membrane properties. Here, we demonstrate that cell-derived giant membrane vesicles can be used as vectors to deliver multiple therapeutic drugs and carry out combinational phototherapy for targeted cancer treatment. We show that therapeutic drugs can be efficiently encapsulated into giant membrane vesicles and delivered to target cells by membrane fusion, resulting in synergistic photodynamic/photothermal therapy under light irradiation. This study highlights biomimetic giant membrane vesicles for drug delivery with potential biomedical application in cancer therapeutics.

Visceral pain originating from chronic inflammation of the pancreas is often intractable and difficult to manage clinically. However, the pathogenesis of the central nervous system underlying visceral pain is still poorly understood. The aim of the present study was to investigate the role of the midbrain ventrolateral periaqueductal gray (vlPAG) in a rat model of chronic visceral pain induced by pancreatitis. In the present study, we used a well-established rat model of chronic pancreatitis induced by tail vein injection of dibutyltin dichloride (DBTC). To assess the DBTC-induced visceral pain, we examined the abdominal withdrawal by von Frey filament test. We further studied the synaptic transmission in the vlPAG by whole-cell patch-clamp electrophysiological recordings. Rats receiving DBTC injection exhibited a significantly increased withdrawal frequency to mechanical stimulation of the abdomen compared to rats injected with vehicle. Interestingly, compared to rats injected with vehicle, we found that neurons dissected from DBTC-treated rats exhibited a significantly decreased synaptic strength, which was revealed by a diminishedα-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/N-methyl-d-aspartic acid (AMPA/NMDA) ratio in the vlPAG. Moreover, our results further demonstrated that neurons obtained from DBTC-treated rats displayed a higher paired-pulse ratio, as well as less frequent and smaller amplitudes of miniature excitatory postsynaptic currents in the vlPAG compared to rats injected with vehicle. Furthermore, intra-vlPAG microinjection of AMPA alleviated DBTC-induced abdominal hypersensitivity. Taken together, our findings suggest that diminished glutamatergic synaptic strength via both presynaptic and postsynaptic mechanisms in the midbrain vlPAG is associated with DBTC-induced abdominal hypersensitivity. In addition, activation of AMPA receptors in the vlPAG alleviates DBTC-induced abdominal hypersensitivity.

Inspired by this elegant system of cellular adaptivity, we herein report the rational design of a dynamic artificial adaptive system able to sense and respond to environmental stresses in a unique sense-and-respond mode. Utilizing DNA nanotechnology, we constructed an artificial signal feedback network and anchored it to the surface membrane of a model giant membrane vesicle (GMV) protocell. Such a system would need to both senses incoming stimuli and emit a feedback response to eliminate the stimuli. To accomplish this mechanistically, our DNA-based artificial signal system, hereinafter termed DASsys, was equipped with a DNA trigger-induced DNA polymer formation and dissociation machinery. Thus, through a sequential cascade of stimulus-induced DNA strand displacement, DASsys could effectively sense and respond to incoming stimuli. Then, by eliminating the stimulus, the membrane surface would return to its initial state, realizing the formation of a cyclical feedback mechanism. Overall, our strategy opens up a route to the construction of artificial signaling system capable of maintaining homeostasis in the cellular micromilieu, and addresses important emerging challenges in bioinspired engineering.

Biomimetic giant membrane vesicles, with size and lipid compositions comparable to cells, have been recognized as an attractive experimental alternative to living systems. Due to the similarity of their membrane structure to that of body cells, cell-derived giant plasma membrane vesicles have been used as a membrane model for studying lipid/protein behavior of plasma membranes. However, further application of biomimetic giant membrane vesicles has been hampered by the side-effects of chemical vesiculants and the utilization of osmotic buffer. We herein develop a facile strategy to derive giant membrane vesicles (GMVs) from mammalian cells in biofriendly medium with high yields. These GMVs preserve membrane properties and adaptability for surface modification and encapsulation of exogenous molecules, which would facilitate their potential biological applications. Moreover, by loading GMVs with therapeutic drugs, GMVs could be employed for drug transport to tumor cells, which represents another step forward in the biomedical application of giant membrane vesicles. This study highlights biocompatible GMVs with biomimicking membrane surface properties and adaptability as an ideal platform for drug delivery strategies with potential clinical applications.

BBS-Net is a novel bifurcated backbone strategy network based on cascaded refinement, which achieves the most advanced performance in RGB-D salient object detection models. However, the performance of the model in multi-scale feature extraction and depth feature enhancement is not strong enough, and the generated saliency maps contain a lot of background distraction and blurred edges. In this paper, based on BBS-Net framework, we adopt more effective feature extraction network and depth feature enhancement module. Specifically, 1) Use the Res2Net-50 structure that constructs hierarchical residual-like connections within a single residual block as a feature extraction network; 2) Use ECA module as channel attention to extract depth information and enhance cross-modal compatibility. The comprehensive experiments of our method on 6 datasets show that it outperforms the original BBS-Net and 7 current state-of-the-art methods in 4 evaluation metrics.

To enable the tempo-spatial distribution monitoring/measurement of ultrafine particles, a cost-effective and miniature plate Electrostatic Aerosol Analyzer (mini-plate EAA) has been designed and characterized in this study for the use in electrical-mobility-based aerosol sizers. The prototype consists of two metal plates, installed in parallel in an insulation block, to establish the zone for particle classification. To minimize the effect of side wall in the classification zone, the length of aerosol entrance slit opening is half of the width of the classification zone. The performance of the mini-plate EAA, i.e., its transmission efficiency and transfer function, were experimentally evaluated for particles with the sizes ranging from 20 to 120 nm. It is shown that the transmission efficiency of singly charged particles was nearly 100% in the sizes larger than 60 nm and was dependent on the aerosol-to-sheath flow rate ratio for particles with the sizes less than 60 nm when operated at the total flow rate of 3.0 lpm. The particle penetration curves as a function of applied voltages were obtained for various combinations of aerosol and sheath flow rates. A modified 2-D model was further proposed to better calculate the cutoff voltage at the 50% penetration. The experimental transfer functions of the mini-plate EAA under the conditions of various aerosol-to-sheath flow rate ratios and at 3.0 lpm sheath flow were given in this study.

Purpose: Gossypol and its analogs, through their ability to bind to and inactivate BH3 domain-containing antiapoptotic proteins, have been shown to inhibit the growth of various human cancer cells in culture and xenograft models. Here, we evaluated the antitumor efficacy of a novel gossypol derivative and BH3 mimetic ch282-5 (2-aminoethanesulfonic acid sodium-gossypolone) in colon cancer models. Several innovative combination strategies were also explored and elaborated. Experimental Design: Ch282-5 was synthesized by modifying the active aldehyde groups and R groups of gossypol according to a computer-aided drug design program. The stability of ch282-5 was examined by high-performance liquid chromatography, and cytotoxic effects of ch282-5 on colon cancer cells were assessed by MTS assay. Activation of mitochondrial apoptotic pathway by ch282-5 was evidenced with a series of molecular biology techniques. In vivo antitumor activity of ch282-5 and its combination with chloroquine, rapamycin, oxaliplatin, and ABT-263 was also evaluated in colon cancer xenograft models and experimental liver metastasis models. Results: Ch282-5 showed antiproliferative and pro-cell death activity against colon cancer cells both in vitro and in vivo, and the response to the drug correlated with inhibition of antiapoptotic Bcl-2 proteins, induction of mitochondria-dependent apoptotic pathway, and disruption of mitophagy and mTOR pathway. Ch282-5 also suppressed liver metastasis produced by intrasplenic injection of colon cancer cells. Furthermore, ch282-5 could potentiate the effectiveness of oxaliplatin and rescue ABT-263 efficacy by downregulation of Mcl-1 and elevation of platelet number. Conclusions: These findings provide a rational basis for clinical investigation of this highly promising BH3 mimetic in colon cancer. Clin Cancer Res; 22(6); 1445–58. ©2015 AACR.

The household sector has been identified as a major driver of the economy and an important contributor to greenhouse gas (GHG) emissions. It is also pointed out by existing studies that influential factors of household emissions range from socioeconomic to geographic aspects. Promoting efficient and feasible decarbonization actions therefore calls for the quantification of the variability in emission patterns and its relationship with contextual factors. In this study, using data on monthly household expenditures at the city level, direct and indirect carbon emissions resulting from household consumption in 51 major Japanese cities in 2011 are calculated. A regression analysis is also conducted to explore the relationship between emissions from the household sector and the socioeconomic, demographic, and climatic characteristics of Japanese cities. Our results indicate seasonality and categorical differences in residential carbon emissions for cities in Japan. We also find per capita income, urban population density, and proportion of the population over 65 years old to be the most influential variables that shape the residential emission landscape of Japanese cities. We thus suggest that seasonality, categories of consumption, and city characteristics be considered as crucial factors in policy making for emission mitigation targeting consumption behavior of urban residents.

MicroRNA-155 (miR-155) has been identified to be overexpressed in various human cancers including osteosarcoma. However, whether the up-regulation of miR-155 is associated with osteosarcoma cancer stem cells (CSCs) is not well understood. In the present study, we showed that miR-155 induced the acquisition of stem-like features in U2OS osteosarcoma cells by increasing the expression of both CSCs surface markers (CD24, CD90, CD133) and CSC-related transcriptional factors (Nanog, SOX2, Oct4, Bim-1). Inflammatory factor TNF-α upregulated the miR-155 expression in U2OS cells and formed a feedback regulatory loop with miR-155. Furthermore, TNF-α/miR-155 axis promoted the cell proliferation, invasion and epithelial-mesenchymal transition (EMT) process in a TP53INP1 independent manner. We also revealed that TNF-α/miR-155 axis induced osteosarcoma CSCs transformation via ERK signaling pathway. These results indicate a crucial role of miR-155 in the acquisition of osteosarcoma CSC phenotype and miR-155 may serve as a potential target in future osteosarcoma therapy.

Domestic trade flourishes with economic development and the spatial separation of production and consumption. Therefore, the prosperity of trade is accompanied by the transfer of pollution from the demand side to the supply side, which could potentially worsen the environmental quality of the supply side. Despite a large number of studies on the pollution haven hypothesis in international trade, little attention has been paid to testing the hypothesis in domestic trade. Here, combining a multiregional input-output analysis and a gravity model of trade in China, we provide an empirical test to address this problem for the first time. We also assess the factors affecting the SO

Abundant studies of cyclic wetting–drying of concrete have suggested a “maximum phenomenon” by which chloride concentrations first increase with depth to a local maximum and then decrease at greater depths. This phenomenon may arise primarily because of carbonation, but may also be exacerbated by cyclic capillary suction and moisture evaporation during wetting–drying cycles. This paper investigates the mechanism responsible for the maximum phenomenon under conditions that exclude cyclic capillary suction. The results show that different chloride maxima form near the surface of all specimens under conditions of either accelerated carbonation or carbonation in normal air environment. A large amount of bound chloride is released when carbonation causes decomposition of Friedel’s salt and C–S–H gel, and the decrease in water content significantly increases the chloride concentration in the pore solution near the specimen surface. The resulting chloride concentration gradient drives free chloride diffusion from the surface to the interior, thereby reducing the actual chloride content near the exposed surface. More severe carbonation conditions increase the severity of the maximum phenomenon.

Among the vast number of recognition molecules, DNA aptamers generated from cell-SELEX exhibit unique properties for identifying cell membrane biomarkers, in particular protein receptors on cancer cells. To integrate all recognition and computing modules within a single structure, a three-dimensional (3D) DNA-based logic gate nanomachine was constructed to target overexpressed cancer cell biomarkers with bispecific recognition. Thus, when the Boolean operator “AND” returns a true value, it is followed by an “ON” signal when the specific cell type is presented. Compared with freely dispersed double-stranded DNA (dsDNA)-based molecular circuits, this 3D DNA nanostructure, termed DNA-logic gate triangular prism (TP), showed better identification performance, enabling, in turn, better molecular targeting and fabrication of recognition nanorobotics.

Employer name normalization, or linking employer names in job postings or resumes to entities in an employer knowledge base (KB), is important for many downstream applications in the online recruitment domain. Key challenges for employer name normalization include handling employer names from both job postings and resumes, leveraging the corresponding location and URL context, and handling name variations and duplicates in the KB. In this paper, we describe the CompanyDepot system developed at CareerBuilder, which uses machine learning techniques to address these challenges. We discuss the main challenges and share our lessons learned in deployment, maintenance, and utilization of the system over the past two years. We also share several examples of how the system has been used in applications at CareerBuilder to deliver value to end customers.

The influence of scale parameter on the simultaneous polarization measurement of high-speed targets using the up and down chirps is analyzed in this paper. A compensation matrix is proposed to compensate the phase error after conventional matched filter (MF). The SNR loss caused by the scale parameter is studied, and the radial velocity error to the compensation accuracy is also discussed. Finally, detailed numerical experiments are conducted to demonstrate the effectiveness of the proposed method.

A DNA reaction network is like a biological algorithm that can respond to "molecular input signals", such as biological molecules, while the artificial cell is like a microrobot whose function is powered by the encapsulated DNA reaction network. In this work, we describe the feasibility of using a DNA reaction network as the computational core of a protocell, which will perform an artificial immune response in a concise way to eliminate a mimicked pathogenic challenge. Such a DNA reaction network (RN)-powered protocell can realize the connection of logical computation and biological recognition due to the natural programmability and biological properties of DNA. Thus, the biological input molecules can be easily involved in the molecular computation and the computation process can be spatially isolated and protected by artificial bilayer membrane. We believe the strategy proposed in the current paper, i.e., using DNA RN to power artificial cells, will lay the groundwork for understanding the basic design principles of DNA algorithm-based nanodevices which will, in turn, inspire the construction of artificial cells, or protocells, that will find a place in future biomedical research.

Based on their unique advantages, increasing interest has been shown in the use of aptamers as target ligands for specific cancer cell recognition and targeted cancer therapy. Recently, the development of aptamer-conjugated nanomaterials has offered new therapeutic opportunities for cancer treatment with better efficacy and lower toxicity. We highlight some of the promising classes of aptamer-conjugated nanomaterials for the specific recognition of cancer cells and targeted cancer therapy. Recent developments in the use of novel strategies that enable sensitive and selective cancer cell recognition are introduced. In addition to targeted drug delivery for chemotherapy, we also review how aptamer-conjugated nanomaterials are being incorporated into emerging technologies with significant improvement in efficiency and selectivity in cancer treatment. New methods of integrating aptamers with various types of nanomaterials are summarized, highlighting promising classes of aptamer-conjugated nanoparticles for efficient cancer cell recognition and the targeted delivery of drugs. In addition, emerging technologies for cancer treatment using nanomaterials as therapeutic drugs are discussed. These aptamer-conjugated nanomaterials will benefit cancer treatment through increased specificity and efficacy as well as reduced toxicity. A major challenge in cancer therapy is the selective targeting of cancerous cells to enhance treatment efficiency and reduce the side effects for patients. A variety of nanostructured materials have recently been developed that, when combined with ligands, are able to recognize the target cells through antigens or receptors. Qiaoling Liu from Hunan University and colleagues in China and the United States review the use of DNA aptamers as ligands. These short, synthetic oligonucleotide strands are cost-effective, exhibit low toxicity and can be attached to a range of nanomaterials - from liposomes and hydrogels to inorganic nanoparticles - to endow them with sensitive and selective cell-recognition abilities. Furthermore, the resulting hybrid nanomaterials can be used in conjunction with conventional treatments, such as photodynamic and photothermal therapies. Although hurdles in their toxicity and efficiency remain to be overcome before they are suitable for real-life cancer treatments, aptamer-conjugated nanomaterials have emerged as a promising theranostic platform.

In the past two decades, the study of cancer therapy has gradually advanced to the "nano" era. Numerous novel nanomaterials armed with unique physical properties have been introduced into biomedical research. At the same time, functional nucleic acid molecules, especially aptamers, have aroused broad attention from the biomedical community. Benefiting from the advancement of molecular engineering strategies, it is now feasible to combine the cancer-specific recognition capability of aptamers with various other special functions of nanomaterials to develop cancer-specific drugs at the nanoscale. Nanodrugs are now offering an unprecedented opportunity to achieve the goal of efficient targeted delivery as well as controlled release. This review highlights some achievements made in multiple aptamer-based nanodrug systems that have emerged in recent years, including studies in the infant stage of "proof-of-concept".

The dispersion of carbon nanotubes (CNTs) within cement-based composite materials plays a key role in determining many essential properties. In this study, a method to quantify the dispersion of CNTs within cement-based composite materials has been developed. The dispersion quantity, D, is measured by the particle size rather than the free-path spacing between particles. The particle sizes are given in terms of the true length/nm rather than pixels. A Gaussian function is used as the probability density function (PDF) fits a Gaussian distribution better than a lognormal distribution depending on the statistical data and the true diameter of CNTs. Higher D values indicate a better dispersion of CNTs in the matrix. The method works well to quantify the dispersion of particles, especially for filaments such as CNTs, and is simple and useful.

Photoactivatable probe-based fluorescent imaging has become an efficient and attractive technique for spatiotemporal microscopic studies of biological events. However, almost all previously reported photoactivatable organic probes have been based on hydrosoluble precursors, which have produced water-soluble active fluorophores able to readily diffuse away from the photocleavage site, thereby dramatically reducing spatial resolution. Hydroxyphenylquinazolinone (HPQ), a small organic dye known for its classic luminescence mechanism through excited-state intramolecular proton transfer (ESIPT), shows strong light emission in the solid state, but no emission in solution. In this work, HPQ was employed as a precursor to develop a localizable, photoactivatable two-photon probe (PHPQ) for spatiotemporal bioimaging applications. After photocleavage, PHPQ releases a precipitating HPQ fluorophore which shows both one-photon and two-photon excited yellow-green fluorescence, thereby producing a localizable fluorescence signal that affords high spatial resolution for bioimaging, with more than 200-fold one-photon and 150-fold two-photon fluorescence enhancement.

Previous studies on embodied emission in China's exports focus on the national aggregate analysis while pay little attention to the interregional emission transfer driven by exports. We used multiregional input–output model of 30 provinces to reexamine the embodied emissions and to capture the interregional linkage in it. Results in 2002–2007 show that SO2 embodied in exports contributes 15.17–22.08% of the total domestic SO2 emissions, and 74.40–78.14% of the embodiment is in exports from the eastern provinces, where over 90% of China's exports occur. However, only about 70% of the embodied emission in eastern China's exports is discharged in the east; an increasing portion (24% to 34%) is released in the central and western provinces as a result of interregional production linkage. Moreover, the interregional connection becomes closer during the 2002–2007 period, which increases the scale and intensity of embodied emission in China's export given large gaps in emission intensity among regions. Further analysis on Guangdong, China's largest export province, shows that the SO2 emissions per unit of output induced by Guangdong's exports are larger than that induced by the province's own exports for most provinces, especially the central and western provinces which are restricted in exports and indirectly export by supporting Guangdong's exports via interregional economic linkage. The results yield important implications for China's export and pollution emission control policy.

The popular optimal control approaches in the heating, ventilation and air conditioning (HVAC) system just focus on the energy consumption mostly. It usually simplifies the thermal comfort issue through using an indoor average temperature, which may result in the improper indoor temperature distribution. The co-simulation technology, which integrates the building energy simulation (BES) and computational fluid dynamics (CFD), can provide a possible solution to avoid the false optimization in the control process. In this paper, a simple co-simulation strategy is presented to integrate the BES and CFD techniques for the HVAC system. The energy simulation and thermal comfort calculation are coupled together and the indoor temperature distribution is embedded into the VAV control process. The CFD–BES co-simulation method is validated in the HVAC simulator of an office building located in Shanghai. With the CFD–BES co-simulation strategy, the indoor temperature sensor placement is optimized though considering the energy consumption and predicted mean vote (PMV) simultaneously. The results show that the commonly selected sensor position of indoor temperature is not always the best solution for the VAV terminal control.

In this work, we have developed a truncated DNA aptamer, termed XQ-2d, with high affinity and specificity for pancreatic ductal adenocarcinoma (PDAC). Aptamer XQ-2d selectively binds to PL45 cells with a dissociation constant in the nanomolar range, as determined by its recognition of PL45 tumor cells in mice. Moreover, XQ-2d shows better recognition ratio for 40 tissue sections of clinical PDAC samples (82.5%) compared to the initial cell-SELEX selection library (5%). Therefore, XQ-2d can be considered a promising candidate as a tool for PDAC diagnosis and treatment.

A series of N-(1,3-diphenylallyl)benzenamine derivatives (M) were investigated by electrospray ionization mass spectrometry in the positive-ion mode. Both the anomalous [M-H]

DNA molecular machines show great promise in fields such as biomarker discovery and biological activity regulation, but operating DNA machines with specific functions within living systems remains extremely challenging. Although DNA machines have been engineered with exact molecular-level specifications, some intrinsic imperfections such as poor cell permeation and fragility in complex cytoplasmic milieu persist due to the well-established character of nucleic acid molecules. To circumvent these problems, we herein report a molecularly engineered, entropy-driven three-dimensional DNA amplifier (EDTD) that can operate inside living cells in response to a specific mRNA target. In particular, mRNA target/EDTD interaction can specifically initiate an autonomous DNA circuit inside living cells owing to the exclusive entropy-driven force, thus providing enormous signal amplification for ultrasensitive detection of the mRNA. Moreover, owing to molecular engineering of a unique DNA tetrahedral framework into the DNA amplifier, EDTD exhibits significantly enhanced biostability and cellular uptake efficiency, which are prerequisites for DNA machines used for in vivo applications. This programmable DNA machine presents a simple and modular amplification mechanism for the detection of intracellular biomarkers. Moreover, this study provides a potentially valuable molecular tool for understanding the chemistry of cellular systems and offers a design blueprint for further expansion of DNA nanotechnology in living systems.

In the recruitment domain, knowing the employer industry of jobs is important to get an insight about the demand in each industry. The existing system at CareerBuilder uses an employer name normalization system and an employer knowledge base to infer the employer industry of a job. However, errors may occur during the computation of the job employer and in the construction of the employer knowledge base with the industry attributes. Since the knowledge base is huge, it is not possible to manually detect the errors. Therefore, in this paper we use Machine Learning techniques to automatically detect the errors. With the observation that the main jobs posted by an employer often relate to the employer industry, e.g., truck driver jobs often correspond to employers belonging to the transportation industry, we develop a system that classifies the industry of an employer using job posting data. We aggregate job postings from an employer and use job titles and employer names as features for predicting the industry of the employer. We used two models for classification: (1) Support Vector Machine, and (2) Gradient Boosted Decision Trees, and observed that while both the models perform similarly in classifying job employers that were correctly computed, GBDT is more effective than SVM in identifying job employers that were wrongly computed. We also show the utility of our system in detecting normalization errors and knowledge base errors.

In this paper, a simulation study on dynamics and polarimetric synthetic aperture radar (PolSAR) imaging of chaff clouds is presented. Based three aerodynamic models of chaff, which are modified based on laboratory observations, the diffusion characteristics of the chaff clouds in the case of three typical distributions are analyzed in detail. Theoretical analysis and simulation results show that the initial orientation distribution and velocity of chaff clouds determine the distribution density and shape after diffusion. On this basis, combined with the polarization scattering model of chaff, the effect of chaff motion on PolSAR imaging is analyzed quantitatively and the imaging results of chaff clouds are also presented in PolSAR. This paper may provide theoretical models and foundation for anti-chaff jamming.

We have developed a DNA nanoprobe for adenosine triphosphate (ATP) sensing in living cells, based on the split aptamer and the DNA triangular prism (TP). In which nucleic acid aptamer was split into two fragments, the stem of the split aptamer was respectively labeled donor and acceptor fluorophores that underwent a fluorescence resonance energy transfer if two ATP molecules were bound as target molecule to the recognition module. Hence, ATP as a target induced the self-assembly of split aptamer fragments and thereby brought the dual fluorophores into close proximity for high fluorescence resonance energy transfer (FRET) efficiency. In the in vitro assay, an almost 5-fold increase in FA/FD signal was observed, the fluorescence emission ratio was found to be linear with the concentration of ATP in the range of 0.03–2 mM, and the nanoprobe was highly selective toward ATP. For the strong protecting capability to nucleic acids from enzymatic cleavage and the excellent biocompatibility of the TP, the DNA TP na...

DNA nanostructures assembled on living cell membranes have become powerful research tools. Synthetic lipid membranes have been used as a membrane model to study the dynamic behavior of DNA nanostructures on fluid soft lipid bilayers, but without the inherent complexity of natural membranes. Herein, we report the assembly and disassembly of DNA nanoprisms on cell-mimicking micrometer-scale giant membrane vesicles derived from living mammalian cells. Three-dimensional DNA nanoprisms with a DNA arm and a cholesterol anchor were efficiently localized on the membrane surface. The assembly and disassembly of DNA nanoprisms were dynamically manipulated by DNA strand hybridization and toehold-mediated strand displacement. Furthermore, the heterogeneity of reversible assembly/disassembly of DNA nanoprisms was monitored by Forster resonance energy transfer. This study suggests the feasibility of DNA-mediated functional biomolecular assembly on cell membranes for biomimetics studies and delivery systems.

Bioconjugation based on crosslinking primary amines to carboxylic acid groups has found broad applications in protein modification, drug development, and nanomaterial functionalization., Bioconjugation based on crosslinking primary amines to carboxylic acid groups has found broad applications in protein modification, drug development, and nanomaterial functionalization. However, proteins, which are made up of amino acids, typically give nonselective bioconjugation when using primary amine-based crosslinking. In order to control protein orientation and activity after conjugation, selective bioconjugation is desirable. We herein report an efficient and cysteine-selective thiol–ene click reaction-based bioconjugation strategy using colloidal nanoparticles. The resulting thiol–ene based aptamer and enzyme nanoconjugates demonstrated excellent target binding ability and enzymatic activity, respectively. Thus, thiol–ene click chemistry can provide a stable and robust crosslinker in a biocompatible manner for bioconjugation of any thiol-containing biomolecule with nanomaterials. This will open more opportunities for applications of thiol–ene reactions and functional colloidal nanoparticles in chemical biology.

Cells interact with the extracellular environment through molecules expressed on the membrane. Disruption of these membrane-bound interactions (or encounters) can result in disease progression. Advances in super-resolution microscopy have allowed membrane encounters to be examined, however, these methods cannot image entire membranes and cannot provide information on the dynamic interactions between membrane-bound molecules. Here, we show a novel DNA probe that can transduce transient membrane encounter events into readable cumulative fluorescence signals. The probe, which translocates from one anchor site to another, mimicking motor proteins, is realized through a toehold-mediated DNA strand displacement reaction. Using this probe, we successfully monitored rapid encounter events of membrane lipid domains using flow cytometry and fluorescence microscopy. Our results show a preference for encounters within the same lipid domains.

Disease-related biomarkers are objectively measurable molecular signatures of physiological status that can serve as disease indicators or drug targets in clinical diagnosis and therapy, thus acting as a tool in support of personalized medicine. For example, the prostate-specific antigen (PSA) biomarker is now widely used to screen patients for prostate cancer. However, few such biomarkers are currently available, and the process of biomarker identification and validation is prolonged and complicated by inefficient methods of discovery and few reliable analytical platforms. Therefore, in this Perspective, we look at the advanced chemistry of aptamer molecules and their significant role as molecular probes in biomarker studies. As a special class of functional nucleic acids evolved from an iterative technology termed Systematic Evolution of Ligands by Exponential Enrichment (SELEX), these single-stranded oligonucleotides can recognize their respective targets with selectivity and affinity comparable to those of protein antibodies. Because of their fast turnaround time and exceptional chemical properties, aptamer probes can serve as novel molecular tools for biomarker investigations, particularly in assisting identification of new disease-related biomarkers. More importantly, aptamers are able to recognize biomarkers from complex biological environments such as blood serum and cell surfaces, which can provide direct evidence for further clinical applications. This Perspective highlights several major advancements of aptamer-based biomarker discovery strategies and their potential contribution to the practice of precision medicine.

An organic salt as a fluorescent probe based on intramolecular charge transfer for Ca(2+) determination is developed. Ca(2+) can be detected by ratiometric emission at 490 and 594 nm with an excitation wavelength of 405 nm. This probe is highly selective for Ca(2+) over other divalent metal cations and displays a large Stokes shift of 189 nm that can avoid interference of the excitation light beam and autofluorescence of biological samples. The dissociation constant for Ca(2+) is 2.25 ± 0.47 μM and pertinent to Ca(2+) detection in cellular resting and dynamic states. The probe demonstrates its application in monitoring Ca(2+) in living cells under confocal microscopic imaging.

To study the influence of multi-wall carbon nanotubes (MWCNTs) on the mechanical and microstructural properties of cementitious composites, 0.00, 0.02, 0.08, 0.10, and 0.20 wt% of multi-wall carbon nanotubes were added into cement mortar, in which the cement-sand ratio was 1:1.5. The flexural and compressive strengths of cement mortar at the age of 3, 7, 28 and 90 d and the fracture performance at the age of 28 d were determined, its 2D micrograph was tested by means of SEM, and the 3D defects distribution was firstly determined with or without CNTs by means of XCT (X-ray computerized tomography). The results showed that 0.08 wt% of CNTs improved the compressive strength and flexural strength by 18% and 19%, respectively, and a significant improvement of its fracture property was observed. Moreover lower addition of carbon nanotubes to cement mortars can improve its microstructure and decrease the defects significantly compared to the cement mortar without CNTs. With the increase of the content of CNTs, the mechanical properties of cement mortars presented to be declined largely due to the agglomeration of CNTs.

Currently, relatively large errors are found in numerical results in some low-specific-speed centrifugal pumps with unshrouded impeller because the effect of clearances and holes are not accurately modeled. Establishing an accurate analytical model to improve performance prediction accuracy is therefore necessary. In this paper, a three-dimensional numerical simulation is conducted to predict the performance of a low-specific-speed centrifugal pump, and the modeling, numerical scheme, and turbulent selection methods are discussed. The pump performance is tested in a model pump test bench, and flow rate, head, power and efficiency of the pump are obtained. The effect of taking into consideration the back-out vane passage, clearance, and balance holes is analyzed by comparing it with experimental results, and the performance prediction methods are validated by experiments. The analysis results show that the pump performance can be accurately predicted by the improved method. Ignoring the back-out vane passage in the calculation model of unshrouded impeller is found to generate better numerical results. Further, the calculation model with the clearances and balance holes can obviously enhance the numerical accuracy. The application of disconnect interface can reduce meshing difficulty but increase the calculation error at the off-design operating point at the same time. Compared with the standard k-ɛ, renormalization group k-ɛ, and Spalart-Allmars models, the Realizable k-ɛ model demonstrates the fastest convergent speed and the highest precision for the unshrouded impeller flow simulation. The proposed modeling and numerical simulation methods can improve the performance prediction accuracy of the low-specific-speed centrifugal pumps, and the modeling method is especially suitable for the centrifugal pump with unshrouded impeller.

Real-world aerosols often vary over time. A time-varied aerosol generation system is thus needed to evaluate the performance of aerosol sensors for characterizing time-dependent aerosol size distribution. However, all laboratory aerosol generators are designed for the production of aerosols with stable concentrations and steady size distributions. A simple way to produce reliable time-dependent aerosols is to combine a stable aerosol generator with a programmable aerosol diluter. Aerosol diluters are also needed to measure aerosols in high concentrations using existing aerosol instruments. In this study we focused on the design and evaluation of a programmable aerosol diluter. The dilution flow rate of the aerosol diluter was controlled by a programmable mass flow controller with a flow rate of up to 200 L/min. Steady and dynamic dilution processes in the diluter were programmed using Visual Basic. Experiments were carried out to characterize the steady and dynamic dilution performance of the aerosol diluter for DMA-classified particles with sizes ranging from 10 nm to 1.0 μm. The steady dilution result shows that the diluter has a non-size dependent dilution performance, and there is a good linear relationship between the aerosol dilution ratio and dilution flow rate ratio (with a calibrated line slope of 1.03, close to the ideal line slope of 1.0). Our experiments further indicate that efficient aerosol mixing in the diluter can be achieved when operated at a flow Reynolds number above 450. The evaluation of four dynamic dilution modes also provides evidence of the excellent performance of the diluter, which has the capability of continuously producing well-defined and concentration-varied aerosols. A simple empirical model was also proposed to describe the steady and dynamic dilution performance of the diluter.

A fast and green approach to synthesise ultrasmall nitrogen (N) and sulfur (S)-doped carbon dots (N,S-C-dots) by microwave-assisted pyrolysis of the precursors rice as carbon source and N-acetyl-L-cysteine (NAC) as N and S dopant has been developed. The obtained N,S-C-dots were fully characterised by elemental analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, UV-vis absorption and photoluminescence (PL) spectroscopy. The undoped C-dots (derived from rice only) and N,S-C-dots possess different chemical compositions, sizes and spectral properties. With the assistance of high-performance liquid chromatography coupled with fluorescence detection (HPLC-FD), the effect of different mass ratios of NAC to rice (NAC/rice) on N,S-C-dots was investigated. Higher NAC/rice ratio benefits the generation of N,S-C-dots with stronger fluorescence emission. In addition, the HPLC separated N,S-C-dots fractions were collected and further characterised by mass spectrometry, UV-vis absorption and PL spectroscopy, showing that the structural changes induced by doping with heteroatoms N and S plays a key role in regulating the PL properties of the N,S-C-dots. This work highlights the merits of synthesising N,S-C-dots from readily available natural bioresources and applying modern HPLC-FD technology to study the effect of doped heteroatoms on N,S-C-dots properties.

In Japan, the National Intended Determined Contributions (INDCs) towards post-2020 GHG emission reductions indicates a reduction of 26.0% is expected by the fiscal year 2030. However, regional emissions allowances have not been fully discussed based on Japan's INDCs target, which considers the regional socio-economic features. Given this, this study points out a soft-path for a fair and efficient quota allocation by proposing an integrated bilevel equilibrium model within a hierarchical structure consisting of the national government and 47 prefectural governments. This proposed model can be changed into a single level solvable equilibrium model, which can be solved by Particle Swarm Optimization (PSO) method. The major findings show that Hokkaido, Tokyo and Osaka were allowed the largest emissions quotas, while Tottori, Saga and Okinawa had the lowest emissions quotas. And the equity is necessary to be considered along with improving the emissions efficiency when reallocating carbon emission quotas, otherwise, the initiative to reduce emissions will not take place in prefectures with higher efficiency performance. Based on the findings, energy policy implications can be generated based on the above quantitative analysis to form a fair and efficient emission quota system at a sub-national level.

Studying the driving factors of pollutant emissions is of great significance for China in the formulation of pollution control strategies. Existing studies mainly focus on the causes of national aggregate emission changes. However, considering the large differences among provinces in China and their close economic linkages, it is necessary to develop a provincial-level analysis to shape provincial policies for emission reduction. Using the multi-regional input-output (MRIO) tables of 30 provinces in China and adopting structural decomposition analysis, we analyze how changes in the end-of-pipe treatment, cleaner production, economic production structure, domestic final use, domestic exports and international exports drive national and provincial SO2 emissions. Decomposition results show that during 2002–2010 the absolute value of each effect based on the MRIO model is higher than that based on the national aggregate input-output model, which indicates that the existing studies adopting the national average data conceal the variation in the driving factors and underestimate their contributions to SO2 emission changes. The decomposition results based on MRIO model further show that the end-of-pipe treatment and cleaner production are the major emission reduction factors for all provinces, and the effect of the former has noticeably increased during 2007–2010. For the eastern provinces, interestingly, the economic production structure becomes a major emission reduction factor during the period of 2007–2010. Changes in domestic final demand, domestic exports and international exports exhibit significantly different contributions among provinces. The increased final demand in eastern provinces largely drive SO2 emissions for all provinces. Based on the above findings, policy implications that address the SO2 emission reduction issues are proposed.

In this paper, the impact of several polarization distortions on geometrical structure retrieval of man-made targets in inverse synthetic aperture radar (ISAR) images is assessed. For polarimetric ISAR, the polarization distortions are usually composed of crosstalk and channel imbalance. For non-stationary targets, a residual phase error exists between two columns of the scattering matrix in the alternate transmission and simultaneous reception (ATSR) mode, especially when the radar frequency is high. These two kinds of distortions have varying influences on different targets, as well as different decomposition methods. Some theoretical derivations and numerical analyses are given to reveal the impact of these distortions on Cameron decomposition. To evaluate the impact of these distortions on geometrical structure retrieval, we use the numerical results and real data of an unmanned aerial vehicle (UAV) called Frontier to perform error analysis of both the decomposition and the retrieved size of the designated structures of the UAV. Some numerical evaluations were conducted from the perspective of system design, and these results can be useful for the practical radar system.

The current jurisdiction-based environmental management paradigm is deficient to address China's growing regional air pollution problems. Based on the foreign management experiences, the “1+N” regional air quality management mode with Chinese characteristics is proposed, which combines the bottom-up and top-down management features among superior and local governments, to cope with the regional air pollution. Several crucial principles are discussed accordingly. In the case study in Pearl River Delta (PRD) region, the PRD Regional Air Quality Management Committee and the Center of Regional Atmospheric Science are carefully designed and are now serving as decision-making body and scientific support agency, respectively. The encouraging practice in the PRD region yields important hints for China's regional air pollution control policy making.

Strategic design of gadofullerene derivatives is critical to integrate multifunctionality into one entity. Herein, an easy method was developed to fabricate a new type of magnetic resonance imaging/fluorescent integrative molecular imaging probe based on Gd@C82. The functionalized gadofulleride Gd@C82O∼14(OH)∼14(NH2)∼6 not only exhibits an order of magnitude larger relaxivity (47.0 ± 0.8 mM−1 s−1 at 0.5 T) than commercially used gadopentetic acid (4.5 ± 0.1 mM−1 s−1) under the same condition and multi-wavelength emission features derived from the multi-wavelength excitation for dual-modality diagnosis, but also highly efficient scavenging capability toward hydroxyl radicals.

To maintain sustained and rapid economic development will be China's strategic goals in a long time. Reducing pollution emission is an important means to coordinate economic development and environment. Identifying the main pathways of pollution reduction and analyzing their contributions has great significance to the pollution control strategies making. This article systematically identified the factors affecting pollution emissions of an open economy and analyzed how changes in pollution abatement, cleaner production, economic spatial structure and trade affect emissions based on decomposition analysis. Case study on China's SO2 emissions in 1995–2010 shows that: (i) on the national level, pollution abatement plays an increasingly significant role in pollution reduction. Cleaner production's contribution is instable, yet most years it declines the emissions. Economic spatial structure shows a positive contribution until 2006 it begins to increase emissions. International trade increases the domestic SO2 emissions in most of the years. (ii) On the regional level, pollution abatement is the most important factor reducing SO2 emissions for the eastern, middle and western China. Trade in the eastern region leads to pollution increase, while has an inverse contribution in the middle and western. The results yield important hints for China's pollution emission control policy making.