How to Evaluate Green Development Policy Based on the PMC Index Model: Evidence from China.

Implementing green development is important to realizing a harmonious relationship between humans and nature, and has attracted the attention of governments all over the world. This paper uses the PMC (Policy Modeling Consistency) model to make a quantitative evaluation of 21 representative green development policies issued by the Chinese government. The research finds: firstly, the overall evaluation grade of green development is good and the average PMC index of China's 21 green development policies is 6.59. Second, the evaluation of 21 green development policies can be divided into four different grades. Most grades of the 21 policies are excellent and good; the values of five first-level indicators about policy nature, policy function, content evaluation, social welfare, and policy object are high, which indicates that the 21 green development policies in this paper are relatively comprehensive and complete. Third, most green development policies are feasible. In twenty-one green development policies, there are: one perfect-grade policy, eight excellent-grade policies, ten good-grade policies, and two bad-grade policies. Fourthly, this paper analyzes the advantages and disadvantages of policies in different evaluation grades by drawing four PMC surface graphs. Finally, based on the research findings, this paper puts forward suggestions to optimize the green development policy-making of China.

How to Evaluate the Level of Green Development Based on Entropy Weight TOPSIS: Evidence from China.

Evaluating the level of green development is of great significance to better implement the concept of green development. By constructing an evaluation index system for green development, this paper comprehensively uses the entropy weight Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) method and coefficient of variation method to evaluate the green development level of 30 provinces in China from 2010 to 2019 and analyzes the regional differences of green development in China. The research findings are as follows: First, the level of green development in China is low but shows a slow rise trend, from 2010 to 2019; China's green development level rises from 0.274 to 0.317, an increase of 15.7%. Secondly, regional differences of green development in China are obvious, with the level ranking from high to low as eastern, western, and central regions. Third, regional differences in China's green development first widen and then narrow, with the variation coefficient of green development in 30 provinces and eastern, central, and western regions of China showing an inverted U-shaped trend of first increasing and then decreasing. Fourth, the regional difference of green development in eastern China is largest, followed by western China, and the smallest is central China. Finally, based on research findings, relevant policy recommendations are put forward.

An Integrated Photoelectrochemical Nanotool for Intracellular Drug Delivery and Evaluation of Treatment Effect.

With reduced background and high sensitivity, photoelectrochemistry (PEC) may be applied as an intracellular nanotool and open a new technological direction of single-cell study. Nevertheless, the present palette of single-cell tools lacks such a PEC-oriented solution. Here a dual-functional photocathodic single-cell nanotool capable of direct electroosmotic intracellular drug delivery and evaluation of oxidative stress is devised by engineering a target-specific organic molecule/NiO/Ni film at the tip of a nanopipette. Specifically, the organic molecule probe serves simultaneously as the biorecognition element and sensitizer to synergize with p-type NiO. Upon intracellular delivery at picoliter level, the oxidative stress effect will cause structural change of the organic probe, switching its optical absorption and altering the cathodic response. This work has revealed the potential of PEC single-cell nanotool and extended the boundary of current single-cell electroanalysis.

A Practical Electrochemical Nanotool for Facile Quantification of Amino Acids in Single Cell.

Though significant advances are made in the arena of single-cell electroanalysis, quantification of intracellular amino acids of human cells remains unsolved. Exemplified by l-histidine (l-His), this issue is addressed by a practical electrochemical nanotool synergizing the highly accessible nanopipette with commercially available synthetic DNAzyme. The fabricated nanotools are screened before operation of a single-use manner, and the l-His-provoked cleavage of the DNA molecules can be sensibly transduced by the ionic current rectification response, the intrinsic property of nanopipette governed by its interior surface charges. Regional distribution of cytosolic l-His level in human cells is electrochemically quantified for the first time, and time-dependent drug treatment effects are further revealed. This work unveils the possibility of electrochemistry for quantification of cytosolic amino acids of a spatial- and time-based manner and ultimately enables a better understanding of amino acid-involved events in living cells.

Photocontrolled Nanopipette Biosensor for ATP Gradient Electroanalysis of Single Living Cells.

Emerging nanopipette tools have demonstrated substantial potential for advanced single-cell analysis, which plays vital roles from fundamental cellular biology to biomedical diagnostics. Highly recyclable nanopipettes with easy and quick regeneration are of special interest for precise and multiple measurements. However, existing recycle strategies are generally plagued by operational complexity and limited efficiency. Light, acting in a noncontact way, should be the ideal external stimulus to address this issue. Herein, we present the photocontrolled nanopipette capable of probing cellular adenosine triphosphate (ATP) gradient at single-cell level with good sensitivity, selectivity, and reversibility, which stems from the use of ATP-specific azobenzene (Azo)-incorporated DNA aptamer strands (AIDAS) and thereby the sensible transduction of variable nanopore size by the ionic currents passing through the aperture. Photoisomerized conformational change of the AIDAS by alternative UV/vis light stimulation ensures its noninvasive regeneration and repeated detection. Inducement and inhibition of the cellular ATP could also be probed by this nanosensor.

An Integrated Electrochemical Nanodevice for Intracellular RNA Collection and Detection in Single Living Cell.

New tools for single-cell interrogation enable deeper understanding of cellular heterogeneity and associated cellular behaviors and functions. Information of RNA expression in single cell could contribute to our knowledge of the genetic regulatory circuits and molecular mechanism of disease development. Although significant progresses have been made for intracellular RNA analysis, existing methods have a trade-off between operational complexity and practical feasibility. We address this challenge by combining the ionic current rectification property of nanopipette reactor with duplex-specific nuclease-assisted hybridization chain reaction for signal amplification to realize a simple and practical intracellular nanosensor with minimal invasiveness, which enables single-cell collection and electrochemical detection of intracellular RNA with cell-context preservation. Systematic studies on differentiation of oncogenic miR-10b expression levels in non-malignant breast cells, metastatic breast cancer cells as well as non-metastatic breast cancer cells were then realized by this nanotool accompanied by assessment of different drugs effects. This work has unveiled the ability of electrochemistry to probe intracellular RNA and opened new opportunities to study the gene expression and heterogeneous complexity under physiological conditions down to single-cell level.

Target-Triggered Assembly in a Nanopipette for Electrochemical Single-Cell Analysis.

Engineered nanopipette tools have recently emerged as a powerful approach for electrochemical nanosensing, which has major implications in both fundamental biological research and biomedical applications. Herein, we describe a generic method of target-triggered assembly of aptamers in a nanopipette for nanosensing, which is exemplified by sensitive and rapid electrochemical single-cell analysis of adenosine triphosphate (ATP), a ubiquitous energy source in life and important signaling molecules in many physiological processes. Specifically, a layer of thiolated aptamers is immobilized onto a Au-coated interior wall of a nanopipette tip. With backfilled pairing aptamers, the engineered nanopipette is then used for probing intracellular ATP via the ATP-dependent linkage of the split aptamers. Due to the higher surface charge density from the aptamer assembly, the nanosensor would exhibit an enhanced rectification signal. Besides, this ATP-responsive nanopipette tool possesses excellent selectivity and stability as well as high recyclability. This work provides a practical single-cell nanosensor capable of intracellular ATP analysis. More generally, integrated with other split recognition elements, the proposed mechanism could serve as a viable basis for addressing many other important biological species.

CdS Quantum Dots Modified Photoelectrochemical Biosensor for TATA-Binding Protein Probing.

The photoelectrochemical (PEC) biosensor, in which light is utilized to excite the photoactive species and current is employed as the detection signal, is a newly appeared yet dynamically developing technique for biological analysis. Based on the assay of DNA binding proteins upon visible light irradiation, a PEC biosensor is constructed for successfully probing a DNA-protein interaction.

Prevalence and recognition of depressive disorders among Chinese older adults receiving primary care: A multi-center cross-sectional study.

BACKGROUND: In recent years, there have been increasing calls for integrating late-life mental health services into primary care in China, but data on the epidemiology of depressive disorders in older adults receiving primary care are very limited. This study examined prevalence, correlates and recognition of depressive disorders among Chinese older adults receiving primary care. METHODS: A total of 752 older patients (65+ years) were consecutively recruited from 13 primary care clinics in Wuhan, China, and interviewed with the Chinese Mini-international Neuropsychiatric Interview 5.0. RESULTS: One-fifth (20.3%) of the older adults met DSM-IV criteria for depressive disorders during the month prior to the interview: 10.2% had major depression, 4.8% had dysthymia, and 5.3% had minor depressive disorder. The recognition rate of older patients with depressive disorders was 1.3% only. In multiple logistic regression analysis, factors significantly associated with depressive disorders included female gender (OR = 1.61), an education of primary school and below (OR = 1.69), poor financial status (OR = 2.44), poor or fair family relationship (OR = 1.66), loneliness (OR = 1.77), hypertension (OR = 1.91), heart disease (OR = 2.02), chronic gastric ulcer (OR = 6.01), and arthritis (OR = 3.55). LIMITATIONS: Older adults from primary care clinics of economically underdeveloped regions of China were not included. CONCLUSIONS: Depressive disorders are prevalent but poorly recognized in Chinese older adults receiving treatment in primary care clinics. In order to improve the emotional well-being and health of older adults, it is time to integrate the management of common mental disorders into primary healthcare in China.

Three-Dimensional TiO2@Cu2O@Nickel Foam Electrodes: Design, Characterization, and Validation of O2-Independent Photocathodic Enzymatic Bioanalysis.

This work reports the innovative design and application of a three-dimensional (3D) TiO2@Cu2O@nickel foam electrode synergized with enzyme catalysis toward the proof-of-concept study for oxygen-independent photocathodic enzymatic detection. Specifically, a 3D-nanostructured photoelectrode has great potential in the semiconductor-based photoelectrochemical (PEC) biological analysis. On the other hand, using various photocathodes, cathodic PEC bioanalysis, especially the photocathodic enzymatic detection, represents an attractive frontier in the field. Different from state-of-the-art photocathodic enzymatic studies that are oxygen-dependent, herein, we present the ingenious design, characterization, and implementation of 3D TiO2@Cu2O@nickel foam photocathodes for the first oxygen-independent example. In such a configuration, the Cu2O acted as the visible-light absorber, while the TiO2 shell would simultaneously function as a protective layer for Cu2O and as a desirable substrate for the immobilization of enzyme biomolecules. Especially, because of the proper band positions, the as-designed photocathode exhibited unique O2-independent PEC property. Exemplified by glucose oxidases, the as-developed sensor exhibited positive response to glucose with good performance. Because various oxidases could be integrated with the system, this protocol could serve as a universal O2-independent platform for many other targets. This work is also anticipated to catalyze more studies in the advanced 3D photoelectrodes toward innovative enzymatic applications.

Revealing transient events of molecular recognition via super-localization imaging of single-particle motion.

Molecular recognition plays an important role in biological systems and relates to a wide range of applications in disease diagnostics and therapeutics. Studies based on steady state or ensemble analysis may mask critical dynamic information of single recognition events. Here we report a study of monitoring the transient molecular recognition via single particle motion. We utilized a super-localization imaging methodology, to comprehensively evaluate the rotational Brownian motion of a single nanoparticle in spatial-temporal-frequential domain, with a spatial accuracy ~20 nm and a temporal resolution of ~10 ms. The transient moment of molecular encountering was captured and different binding modes were discriminated. We observed that the transient recognition events were not static states of on or off, but stochastically undergoes dynamical transformation between different binding modes. This study improves our understanding about the dynamic nature of molecular recognition events beyond the ensemble characterization via binding constant.

Ultrasmall Nanopipette: Toward Continuous Monitoring of Redox Metabolism at Subcellular Level.

Ionic current rectification (ICR) based nanopipettes allow accurate monitoring of cellular behavior in single living cells. Herein, we proposed a 30 nm nanopipette functionalized with G-quadruplex DNAzyme as an efficient biomimetic recognizer for ROS generation at subcellular level via the changes of current-voltage relationship. Taking advantages of the ultra-small tip, the nanopipette could penetrate into a single living cell repeatedly or keep measuring for a long time without compromising the cellular functions. Coupled with precision nanopositioning system, generation of ROS in mitochondria in response to cell inflammation was determined with high spatial resolution. Meanwhile, the changes of aerobic metabolism in different cell lines under drug-induced oxidative stress were monitored continuously. We believe that the ICR-nanopipette could be developed as a powerful approach for the study of cellular activities via electrochemical imaging in living cells.

Organic Photo-Electrochemical Transistor-Based Biosensor: A Proof-of-Concept Study toward Highly Sensitive DNA Detection.

Organic bioelectronics have shown promising applications for various sensing purposes due to their significant advantages in term of high flexibility, portability, easy fabrication, and biocompatibility. Here, a new type of organic device, organic photo-electrochemical transistor (OPECT), is reported, which is the combination of an organic electrochemical transistor and a photo-electrochemical gate electrode modified with CdS quantum dots (QDs). Thanks to the inherent amplification function of the transistor, the OPECT-based biosensor exhibits much higher sensitivity than that of a traditional biosensor. The sensing mechanism of the OPECT is attributed to the charge transfer between the photosensitive semiconductor CdS QDs and the gate electrode. In an OPECT-based DNA sensor, target DNA is labeled with Au nanoparticles (NPs) and captured on the gate electrode, which can influence the charge transfer on the gate caused by the exciton-plasmon interactions between CdS QDs and Au NPs. Consequently, a highly sensitive and selective DNA sensor with a detection limit of around 1 × 10-15 m is realized. It is expected that OPECTs can be developed as a high-performance platform for numerous biological detections in the future.

Semiconducting Organic-Inorganic Nanodots Heterojunctions: Platforms for General Photoelectrochemical Bioanalysis Application.

In this study, semiconducting organic polymer dots (Pdots) and inorganic quantum dots (Qdots) were first utilized to construct the organic-inorganic nanodots heterojunction for the photoelectrochemical (PEC) bioanalysis application. Specifically, n-type CdS Qdots, p-type CdTe Qdots, and tetraphenylporphyrin (TPP)-doped poly[(9,9-dioctylfluorenyl-2,7-diyl)- co-(1,4-benzo-{2,1',3}-thiadazole)] (PFBT) Pdots were fabricated, and their energy levels, that is, their valence band (VB)/conduction band (CB) or lowest unoccupied molecular orbital (LUMO)/highest occupied molecular orbital (HOMO) values, were also determined. Then, these nanodots were integrated to construct four types of p-n and p-p organic-inorganic nanodots heterojunctions, that is, CdS Qdots/TPP-doped PFBT Pdots, TPP-doped PFBT Pdots/CdS Qdots, CdTe Qdots/TPP-doped PFBT Pdots, and TPP-doped PFBT Pdots/CdTe Qdots, on the transparent glass electrode. Upon light irradiation, four heterojunctions exhibited different PEC behaviors with some having prominent photocurrent enhancement. With the model molecule l-cysteine (l-cys) as target, the proposed PEC sensor exhibited good performances. In brief, this work presents the first semiconducting organic-inorganic nanodots heterojunction for PEC bioanalysis application, which could be easily used as a general platform for future PEC bioanalysis building. Besides, it is expected to inspire more interest in the design, development, and implementation of various organic-inorganic heterojunctions for advanced PEC bioanalysis in the future.

Bismuth Oxyiodide Couples with Glucose Oxidase: A Special Synergized Dual-Catalysis Mechanism for Photoelectrochemical Enzymatic Bioanalysis.

On the basis of a special synergized dual-catalysis mechanism, this work reports the preparation of a BiOI-based heterojunction and its use for cathodic photoelectrochemical (PEC) oxidase biosensing, which, unexpectedly, revealed that hydrogen peroxide (H2O2) had a greater impact than dioxygen (O2). Specifically, the BiOI layer was in situ formed on the substrate through an impregnating hydroxylation method for the following coupling with the model enzyme of glucose oxidases (GOx). The constructed cathodic PEC enzyme sensor exhibited a good analytical performance of rapid response, high stability, and good selectivity. Especially, glucose-induced H2O2-controlled enhancement of the photocurrent was recorded rather than the commonly observed O2-dependent suppression of the signal. This interesting phenomenon was attributed to a special synergized dual-catalysis mechanism. Briefly, this study is expected to provide a new BiOI-based photocathode for general PEC bioanalysis development and to inspire more interest in the design and construction of a novel heterojunction for advanced photocathodic bioanalysis. More importantly, the mechanism revealed here would offer a totally different perspective for the use of a biomimetic catalyst in the design of future PEC enzymatic sensing and the understanding of relevant signaling routes as well as the implementation of innovative PEC devices.

Nanochannels Photoelectrochemical Biosensor.

Nanochannels have brought new opportunities for biosensor development. Herein, we present the novel concept of a nanochannels photoelectrochemical (PEC) biosensor based on the integration of a unique CuxO-nanopyramid-islands (NPIs) photocathode, an anodic aluminum oxide (AAO) membrane, and alkaline phosphatase (ALP) catalytic chemistry. The CuxO-NPIs photocathode possesses good performance, and further assembly with AAO yields a designed architecture composed of vertically aligned, highly ordered nanoarrays on top of the CuxO-NPIs film. After biocatalytic precipitation (BCP) was stimulated within the channels, the biosensor was used for the successful detection of ALP activity. This study has not only provided a novel paradigm for an unconventional nanochannels PEC biosensor, which can be used for general bioanalytical purposes, but also indicated that the new concept of nanochannel-semiconductor heterostructures is a step toward innovative biomedical applications.

Photoelectrochemical Bioanalysis Platform of Gold Nanoparticles Equipped Perovskite Bi4NbO8Cl.

We have developed sensitive photoelectrochemical (PEC) detection of cysteine using the gold nanoparticles (Au NPs) equipped perovskite Bi4NbO8Cl heterostructure. The Bi4NbO8Cl was prepared by a solid-state reaction, and the Au NPs/Bi4NbO8Cl electrode was made through the electrostatic layer-by-layer self-assembly technique. The Au NPs/Bi4NbO8Cl electrode provided much enhanced photocurrent with a great increase compared to the bare Bi4NbO8Cl electrode and allowed for the plasmon-enhanced PEC detection of cysteine with good performance. It demonstrated rapid response, high stability, wide linear detection range and certain selectivity, implying its great promise in its application. Therefore, the Au NPs/Bi4NbO8Cl heterostructure has provided a promising platform for the development of PEC bioanalysis. More generally, these findings offered an insight into the exploitation of perovskite materials for PEC bioanalytical purposes.

Quantum-dots-based photoelectrochemical bioanalysis highlighted with recent examples.

Photoelectrochemical (PEC) bioanalysis is a newly developed methodology that provides an exquisite route for innovative biomolecular detection. Quantum dots (QDs) are semiconductor nanocrystals with unique photophysical properties that have attracted tremendous attentions among the analytical community. QDs-based PEC bioanalysis comprises an important research hotspot in the field of PEC bioanalysis due to its combined advantages and potentials. Currently, it has ignited increasing interests as demonstrated by increased research papers. This review aims to cover the most recent advances in this field. With the discussion of recent examples of QDs-PEC bioanalysis from the literatures, special emphasis will be placed on work reporting on fundamental advances in the signaling strategies of QDs-based PEC bioanalysis from 2013 to now. Future prospects in this field are also discussed.

Simultaneous photoelectrochemical and visualized immunoassay of ß-human chorionic gonadotrophin.

Herein, on the basis of the alkaline phosphate (ALP) induced reaction, a simultaneous photoelectrochemical (PEC) and visualized immunoassay has been established for the detection of ß-human chorionic gonadotrophin (ß-HCG). Specifically, in the proposed system, ALP stimulated the oxidative hydrolyzing transformation of 5-bromo-4-chloro-3-indoyl phosphate (BCIP) to an indigo precipitation, generating an insulating layer that impeded the interfacial mass and electron transfer and thus the photocurrent production. Meanwhile, a visualized detection could be performed according to the change of color intensity. Upon proper experimental conditions, the protocol possessed a detection range of 0.5-1000IU/L with a detection limit of (0.20±0.011)IU/L toward ß-HCG. With high sensitivity and specificity, this work presents the first general protocol for simultaneous PEC and visualized detection, which could be easily extended to addressing numerous other targets.

Alkaline Phosphatase Tagged Antibodies on Gold Nanoparticles/TiO2 Nanotubes Electrode: A Plasmonic Strategy for Label-Free and Amplified Photoelectrochemical Immunoassay.

This work reports a plasmonic strategy capable of label-free yet amplified photoelectrochemical (PEC) immunoassay for the sensitive and specific detection of model protein p53, an important transcription factor that regulates the cell cycle and functions as a tumor suppressor. Specifically, on the basis of Au nanoparticles (NPs) deposited on hierarchically ordered TiO2 nanotubes (NTs), a protein G molecular membrane was used for immobilization of alkaline phosphatase (ALP) conjugated anti-p53 (ALP-a-p53). Due to the immunological recognition between the receptor and target, the plasmonic charge separation from Au NPs to the conduction band of TiO2 NTs could be influenced greatly that originated from multiple factors. The degree of signal suppression is directly associated with the target concentration, so by monitoring the changes of the plasmonic photocurrent responding after the specific binding, a new plasmonic PEC immunoassay could be tailored for label-free and amplified detection. The operating principle of this study could be extended as a general protocol for numerous other targets of interest.