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Understanding soil water dynamics in the deep vadose zone (DVZ, below the root zone) of irrigated farmland is critical for estimating groundwater recharge and assessing the impacts of agricultural activities on groundwater quality. However, the state and movement of soil water in the DVZ remain poorly understood owing to the lack of in‐situ observations. Here, based on a 48‐m deep caisson (Critical Zone Observatory, CZO) established in a typical irrigated farmland in the piedmont region of the North China Plain, we extended the monitoring of soil water content and matric potential across the entire vadose zone profile. We found that a high soil water content and matric potential (close to or slightly higher than the field capacity) was maintained in the DVZ of typical irrigated cropland. The response of soil water in the DVZ to the water inputs at the ground surface was predominantly sequentially delayed with an increase in depth in the DVZ. As a result, the wetting front propagated into the soil layer to a depth of 38 m within 228 days. Moreover, high soil moisture contents and matric potentials in the DVZ resulted in a dramatic but explicable difference between the estimated average pore water velocity (0.73 m year−1) and the wetting front propagation rate (0.16 m day−1). This study demonstrates the unreported rapid response of soil water in the DVZ to water input at the ground surface under intensively irrigated cropland and could promote a better understanding of groundwater recharge processes with a thick unsaturated zone. Key Points: We construct a 48‐m deep caisson in a typical irrigated farmland to monitor soil water dynamics across the entire vadose zone profileLong‐term and intensive irrigation favors high water contents and matric potential (close to or higher than field capacity) below root zoneHeavy rainfall promoted to push the wetting front to reach as deep as 38 m within 228 days [ABSTRACT FROM AUTHOR]

Aims: To evaluate the efficacy and safety of janagliflozin, a selective renal sodium‐glucose cotransporter‐2 inhibitor, as monotherapy in drug‐naive Chinese patients with type 2 diabetes mellitus (T2DM). Materials and methods: This Phase 3 trial included a 24‐week, multicentre, randomized, double‐blind, placebo‐controlled period, followed by a 28‐week extension period. A total of 432 patients with glycated haemoglobin (HbA1c) levels ≥7.0% (53 mmol/mol) and ≤10.5% (91 mmol/mol) were randomized (1:1:1) to receive once‐daily placebo, 25 mg or 50 mg janagliflozin. After 24 weeks, patients on placebo were switched and re‐randomized (1:1) to 25 mg or 50 mg janagliflozin, whereas patients on janagliflozin maintained the initial therapy. The primary endpoint was change from baseline in HbA1c after 24 weeks. Results: At Week 24, the placebo‐adjusted least squares mean changes in HbA1c were −0.80% (95% confidence interval [CI] −0.98% to −0.62%)/−8.7 mmol/mol (95% CI −10.7 mmol/mol to −6.8 mmol/mol) and −0.88% (95% CI −1.06% to −0.70%)/−9.6 mmol/mol (95% CI −11.6 mmol/mol to −7.7 mmol/mol), respectively (P < 0.001 for both). A higher proportion of patients achieved HbA1c <7.0% (53 mmol/mol) with janagliflozin 25 mg and janagliflozin 50 mg compared with placebo (47.2%, 49.3%, and 23.5%, respectively). Both janagliflozin doses significantly decreased fasting plasma glucose, 2‐hour postprandial glucose, body weight and systolic blood pressure, as well as increased high‐density lipoprotein (HDL) cholesterol and insulin sensitivity compared with placebo (P < 0.05 for all). The trends in improvement of these variables were sustained during the 28‐week extension period. Overall incidences of adverse events were 67.8%, 71.5% and 60.7% with janagliflozin 25 mg, janagliflozin 50 mg and placebo, respectively. The incidence of urinary tract infections and genital fungal infections was low. No severe hypoglycaemia or ketoacidosis occurred. Conclusions: Janagliflozin 25 mg and 50 mg monotherapy once‐daily effectively improved glycaemic control, reduced body weight and blood pressure, improved HDL cholesterol and insulin sensitivity, and was generally well tolerated. [ABSTRACT FROM AUTHOR]

As the core of polymer chemistry, manufacture of functional polymers is one of research hotspots over the past several decades. Various polymers are developed for diverse applications due to their tunable structures and unique properties. However, traditional step‐by‐step preparation strategies inevitably involve some problems, such as separation, purification, and time‐consuming. The multicomponent reactions (MCRs) are emerging as environmentally benign synthetic strategies to construct multifunctional polymers or composites with pendant groups and designed structures because of their features, such as efficient, fast, green, and atom economy. This mini review summarizes the latest advances about fabrication of multifunctional fluorescent polymers or adsorptive polymeric composites through different MCRs, including Kabachnik–Fields reaction, Biginelli reaction, mercaptoacetic acid locking imine reaction, Debus–Radziszewski reaction, and Mannich reaction. The potential applications of these polymeric composites in biomedical and environmental remediation are also highlighted. It is expected that this mini‐review will promote the development preparation and applications of functional polymers through MCRs. [ABSTRACT FROM AUTHOR]

Highly‐efficient charge separation is of significant importance for the improvement of photocatalytic performance towards solar H2 production. Here, Ag2S/CdS hetero nanorods with intimate contact were fabricated at ambient temperature by L‐cysteine‐assisted method involving a Triton X‐100/cyclohexane/hexanol/water quaternary W/O reverse microemulsion process. The formation of Ag2S/CdS nanojunction is verified by XRD, TEM, HRTEM, EDS as well as XPS technique, while the photocatalytic activity of Ag2S/CdS hetero nanorod is assessed by water photo‐reduction to H2 in the presence of S2−/SO32− as sacrificial agents under visible‐light irradiation. It is demonstrated that Ag2S/CdS hetero nanorod exhibits an about 480‐fold enhancement in the H2‐evolution rate relative to that of pristine CdS. In combination with UV‐vis absorption and photoluminescence spectra, the synergistic effects stemmed from the extended light‐absorption and facilitated charge‐separation between the interfaces largely contribute to boosting the photocatalytic H2‐evolution activity of CdS nanorod. This work offers a novel strategy to in‐situ construct CdS‐based heterostructured photocatalysts with good performance and low cost. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE) is an abnormal phenomenon that has sparked great attention for diverse applications in different fields. In particular, the fabrication and biological imaging applications of AIE-active fluorescent organic nanoparticles (FONs) have become a focus in the emerging and promising fields. A large number of AIE-active polymeric nanoprobes have recently been fabricated through different strategies. The advances and progress in this direction have also recently been summarized by some groups. However, the fabrication and biomedical applications of AIE-active FONs based on carbohydrate polymers and AIE-active dyes are quite rare and limited. In this feature article, the recently reported AIE-active FONs with different structures and applications based on AIE-active dyes and carbohydrate polymers are highlighted, and the major current limitations and development tendencies are also discussed. [ABSTRACT FROM AUTHOR]

Fluorescent polymeric nanoparticles (FPNs) with aggregation-induced emission (AIE) property have received increasing attention and possess promising biomedical application potential in the recent years. Many efforts have been devoted to the fabrication methodologies of FPNs and significant advance has been achieved. In this contribution, a novel strategy for the fabrication of AIE-active amphiphilic copolymers is reported for the first time based on the Ce(IV) redox polymerization. As an example, ene group containing AIE-active dye (named as Phe-alc) is directly grafted onto a water soluble polymer polyethylene glycol (PEG) in H2O/THF system under low temperature. Thus-obtained amphiphilic fluorescent polymers will self-assemble into FPNs with ultra-low critical micelle concentration, ultra-brightness, and great water dispersibility. Biological evaluation results suggest that the PEG-poly(Phe-alc) possess excellent biocompatibility and can be used for tracing their behavior in cells using confocal laser scanning microscope. These features make PEG-poly(Phe-alc) FPNs promising candidates for many biomedical applications, such as cell imaging, drug delivery vehicles, and targeted tracing. More importantly, many other functional groups can also be incorporated into these AIE-active FPNs through the redox polymerization. Therefore, the redox polymerization should be a facile and effective strategy for fabrication of AIE-active FPNs. [ABSTRACT FROM AUTHOR]

The development of effective strategies for fabrication of fluorescent organic nanoparticles (FONs) with an aggregation-induced emission (AIE) feature has an important impact on the biomedical applications of these AIE-active FONs. In the current work, an ultrafast strategy for fabricating AIE-active FONs is developed through a 'one-pot' microwave-assisted, catalysts-free, and solvent-free Kabachnik-Fields (KF) reaction for the first time. It is demonstrated that such organophosphorous-containing AIE-active block polymers can be synthesized within 2 min under air atmosphere through the microwave-assisted KF reaction. These polymers show amphiphilic properties and can self-assemble into mPEG-CHO-Phe-NH2-DEP FONs, which display high water dispersibility and desirable optical properties. Biological evaluation results suggest that the mPEG-CHO-Phe-NH2-DEP FONs exhibit low toxicity and are potential for biological imaging applications. More importantly, many other multifunctional AIE-active FONs can also be fabricated through the strategy described in this work owing to the universality of KF reaction. Besides, combined with the excellent properties of mPEG-CHO-Phe-NH2-DEP FONs, it is believed that such microwave-assisted KF reaction shall be an effective route for designing various AIE-active nanomaterials for different biomedical applications. [ABSTRACT FROM AUTHOR]

Driven by the high demand for sensitive and specific tools for optical imaging, fluorescent nanoprobes with various working mechanisms and advanced functionalities are flourishing at an incredible speed. This work reports the design and fabrication of aggregation-induced emission (AIE)-active fluorescent organic nanoparticles (FNPs) via forming dynamic phenyl borate between diol containing hydrophobic AIE dye (APD-PhCHO) and phenylboronic acid pendant hydrophilic polymers (PEGMA-VPBA) within 30 min. The final AIE-active APD-PhCHO-PEGMA-VPBA FNPs display high water dispersibility and strong fluorescence emission because of their amphiphilic properties and AIE feature. Biological evaluation suggests that APD-PhCHO-PEGMA-VPBA FNPs possess negative effect on HeLa cells and desirable optical properties for biological imaging. More importantly, phenyl borate is a dynamic bond with pH and glucose responsiveness. Furthermore, different functions can be designed and introduced into these AIE-active systems through adoption of different monomers for good applicability of free radical polymerization. Therefore, this work provides a novel platform for preparation of multifunctional AIE-active nanosystems with responsiveness for various biomedical applications. [ABSTRACT FROM AUTHOR]

ABSTRACT Surface functionalization of carbon nanotubes (CNTs) with a thermo responsive polymer was achieved via combination of mussel inspired chemistry and surface initiated single electron transfer living radical polymerization (SET-LRP). In this procedure, CNTs were first coated with polydopamine (PDA) through self polymerization under a rather mild condition. And then PDA functionalized CNTs bearing with amino and hydroxyl groups were further reacted with bromo isobutyryl bromide. Finally, a thermo responsive polymer poly(N-isopropylacrylamide) (PNIPAM) was introduced on the CNTs via SET-LRP. The successful surface modification of CNT-PDA-PNIPAM was evidenced by a series of characterization techniques. The resulting CNT-PDA-PNIPAM showed significant enhancement of dispersibility in both aqueous and organic solvents. More importantly, these CNT-polymer nanocomposites showed obvious thermo responsive behavior due to the surface coating CNTs with PNIPAM. As compared with previous methods, this method is not required oxidation of CNTs to introduce funcitonal groups for immobilization of the polymerization initiators. More importantly, this method could also be utilized for fabricating many other polymer nanocomposites because of the strong and universal adhesive of PDA to various materials. It is therefore, the novel strategy via marrying mussel inspired chemistry with SET-LRP should be a simple, general and effective method for surface functionalization. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1872-1879 [ABSTRACT FROM AUTHOR]

Bio-inspired nanochannels have emerged as an interface to mimic the functionalities of biological nanochannels. One remaining challenge is to develop double-gated nanochannels with dual response, which can regulate the ion transport direction by alternately opening and closing the two gates. In this work, a bio-inspired potassium and pH responsive double-gated nanosystem is presented, constructed through immobilizing C-quadruplex and G-quadruplex DNA molecules onto the top and bottom tip side of a cigar-shaped nanochannel, respectively. It is demonstrated that the two gates of the nanochannel can be opened and closed alternately/simultaneously. This phenomenon results from the attached DNA conformational transition caused by adjusting the concentrations of potassium ion and proton. This design is believed to be the first example of dual-responsive double-gated nanosystem, and paves a new way to investigate more intelligent bio-inspired nanofluidic system. [ABSTRACT FROM AUTHOR]

A composite-hydroxide mediated (CHM) method was utilized for the synthesis of CuO peony-flower nanostructures under temperatures ranging between 25 and 160 °C. The CHM mechanism was confirmed through X-ray Powder Diffraction (XRD) and a Thermo-Gravimetric Differential Scanning Calorimeter (TG-DSC). Cu(NO3)2 was shown to transform into Cu(OH)2 in the mixed alkalis (NaOH/KOH); the reaction was facilitated by the solvent properties of the mixed alkalis. Cu(OH)2 subsequently consumed H2O in the adsorption of the mixed alkalis at 25∼65 °C. At higher reaction temperatures (>65 °C), the Cu(OH)2 was seen to decompose at an accelerated rate. Therefore, crystalline CuO could be obtained not only above 65 °C but also at 25 °C. The crystal morphology and structure of CuO were examined through Filed Emission Scanning Electron Microscopy (FE-SEM) and Transmission Electron Microscopy (TEM). It was determined that the CuO peony-flower had a polycrystalline structure composed of single crystalline CuO petals. Using the Selected Area Electron Diffraction (SAED) results, the rings were indexed as (002), (111), (112), (202) and (−113), which was in agreement with the XRD results. With increasing temperature, the CuO flower petals self-assembled through random aggregation and gathered CuO nanorod parts, which led to incomplete CuO flower petals through orientated aggregation. Prolonged reaction time led to the growth of CuO flower petals in the direction of [001]. An ideal CuO flower structure was observed through TEM observation. [ABSTRACT FROM AUTHOR]