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In this paper, an efficient full wave electromagnetic (EM) design and optimization method for ultra-wideband bandpass filter is proposed. An ultra-wideband bandpass filter with 100% fractional bandwidth is designed using Sonnet EM simulator to verify the proposed method. The proposed method follows a sequential optimization process where a group of single terminated sub-networks are established by successively adding, extracting and optimizing design parameters, by using this segmented design method, only a few couplings and resonators are designed and optimized in each design stage, which improve the convergence of the whole process. Moreover, the frequency dependent couplings which are not covered in conventional coupling matrix model are well characterized by extracting the input impedance of the single terminated sub-network over the ultra-wide frequency range of interest from the reflected group delay response. The space mapping technique is employed to improve the EM based optimization process. By using the method, excellent agreement between the EM response and the design specification is obtained in the ultra-wideband bandpass filter design example.

Herein we report a novel C–S bond cleavage and reconstruction strategy for the synthesis of thiocyanates through direct photocatalytic S–H bond cyanation from thiols and inorganic thiocyanate salts. In our strategy, the unprecedented example of cutting off C–S bond of SCN– to deliver the green “CN” sources is demonstrated. This transformation features nontoxic and inexpensive “CN” sources, available starting materials, metal-/base-/ligand-/peroxide-free, high step economy and mild conditions. It leads to the construction of various thiocyanates and some medicinally and biologically active thiocyanate-containing molecules.

Background To increase the production of bioethanol, a two-step process based on hydrothermal and dilute alkaline treatment was applied to reduce the natural resistance of biomass. However, the process required a large amount of water and a long operation time due to the solid/liquid separation before the alkaline treatment, which led to decrease the pure economic profit for production of bioethanol. Therefore, four one-step processes based on order of hydrothermal and alkaline treatment have been developed to enhance concentration of glucose of wheat straw by enzymatic saccharification. The aim of the present study was to systematically evaluated effect for different one-step processes by analyzing the physicochemical properties (composition, structural change, crystallinity, surface morphology, and BET surface area) and enzymatic saccharification of the treated substrates. Results In this study, hemicelluloses and lignins were removed from wheat straw and the morphologic structures were destroyed to various extents during the four one-step processes, which were favorable for cellulase absorption on cellulose. A positive correlation was also observed between the crystallinity and enzymatic saccharification rate of the substrate under the conditions given. The surface area of the substrate was positively related to the concentration of glucose in this study. As compared to the control (3.0 g/L) and treated substrates (11.2–14.6 g/L) obtained by the other three one-step processes, the substrate treated by one-step process based on successively hydrothermal and alkaline treatment had a maximum glucose concentration of 18.6 g/L, which was due to the high cellulose concentration and surface area for the substrate, accompanying with removal of large amounts of lignins and hemicelluloses. Conclusions The present study demonstrated that the order of hydrothermal and alkaline treatment had significant effects on the physicochemical properties and enzymatic saccharification of wheat straw. The one-step process based on successively hydrothermal and alkaline treatment is a simple operating and economical feasible method for the production of glucose, which will be further converted into bioethanol.

In this paper, a cascade design procedure exploiting segmented approach and the space mapping technique is proposed for efficient EM-based design optimization of high order microwave bandpass filters. The theory of the proposed method is discussed in detail. The optimization routine is presented. A ten pole hairpin microstrip filter is optimized efficiently using Keysight ADS and Sonnet EM simulator to validate the proposed method.

In this paper, a frequency-dependent implicit space mapping method is proposed for the prototyping of wideband microwave device. In the proposed method, frequency-dependent mapping is established between the fabricated device and a fast surrogate model. In this way, the practical variance of electromagnetic properties in a wide frequency range can be properly approximated. The parameter extraction process becomes more reliable, the runs of fabrication can be significantly reduced. To verify the proposed method, a wideband impedance transformer is fabricated and tested as an example. The testing results achieve design specification within only two fabrications.

Design of circular polarization (CP) antennas requires accounting for several and normally conflicting objectives that include ensuring sufficient impedance bandwidth and low level of axial ratio (AR). For an increasing number of modern applications, reduction of the antenna size becomes of importance. Design closure of CP antennas is often carried out having in mind electrical and field properties, whereas miniaturization is a byproduct of introduced topological modifications. In this paper, we apply multi-objective optimization as a tool for generating the best possible design trade-offs for a compact CP antenna with respect to its reflection response, axial ratio and the size. A particular example of a planar microstrip structure with elliptical ground plane slots and dual feed line stubs is considered. Surrogate-assisted optimization framework allows for finding a set of Pareto optimal designs at a low computational cost, giving the designer an insight into the capabilities of the antenna, particularly in terms of relationships between achievable miniaturization ratio as well as the axial ratio and reflection bandwidths. For the considered example, it is possible to reduce the antenna size by over 11 percent while maintaining required AR bandwidth, or reduce maximum in-band AR to 1.3 dB while ensuring required impedance bandwidth.

An AIE based tetraphenylethylene derivative (MOTIPS-TPE) with a pyridinium pendant was synthesized for light-up sensing of F− in aqueous solution without additives. The fluoride ion promoted cleavage reaction gave MOTIPS-TPE high selectivity toward F− over other common anions. Moreover, MOTIPS-TPE can be used to monitor F− in living HeLa cells.

It is greatly important to seek a fast and sensitive method for the detection of Cu2+ ions because of their vital role in the human body. Fluorescent probes, especially the rhodamine derivatives, have been considered as promising candidates for detection of Cu2+ ions due to their attractive features. However, one problem frequently encountered in rhodamine-based fluorescent probes is that some of them could not distinguish Cu2+ from Hg2+ and these drawbacks limit their application in biological samples. In this paper, a rhodamine B derivative (RBH) was grafted to mesoporous silica coated upconversion nanoparticles (CS-UCNP) to fabricate a new organic–inorganic hybrid nanoprobe. On addition of Cu2+ ions, an emission band at about 580 nm appeared while the intensity of the green emission at about 545 nm of the nanoprobe decreased upon excitation of a 980 nm laser, implying that a luminescence resonance energy transfer (LRET) happened from the CS-UCNP to the RBH–Cu2+ complex. The obtained LRET nanoprobe could detect Cu2+ exclusively even in the presence of Hg2+ with a detection limit of 0.82 μM in absolute ethanol solution. Most importantly, this nanoprobe can be used for monitoring subcellular distribution of Cu2+ in living cells based on upconversion luminescence and downconversion fluorescence.

A dispersion-corrected DFT study on the redox-induced linkage isomerization of a family of [M(bpy)2AL]2+ complexes {M = Ru, Os; bpy = 2,2-bipyridine; AL = 2-[(isopropylsulfinyl)methyl]pyridine (pySO), 2-[2-(isopropylsulfinyl)ethyl]pyridine (pyESO), 2-[3-(isopropylsulfinyl)propyl]pyridine (pyPSO)} was undertaken. The calculated results indicated that modification of the metal center or ancillary ligand could produce distinct electronic and photophysical properties of the complexes. In good agreement with experimental absorption spectrum results, a redshift in the absorption maximum was observed if the metal center of the complex was changed from ruthenium to osmium. More importantly, the relative thermodynamic stabilities of the two linkage isomers in these complexes could also be tuned by modifications to the metal center or ancillary ligand. It was found that the relative energies between the S- and O-linked ruthenium sulfoxide complexes were smaller than those between the osmium sulfoxide isomers. Intrinsic reaction pathway results demonstrated that intramolecular SO and OS isomerization was easier in the ruthenium complexes than in the osmium complexes with the same coordinated ligands. Moreover, intramolecular isomerization was more favorable if the number of methylene units between the sulfoxide group and the pyridine ring in the ancillary ligand was increased.

The effect of metal ions (Mn+ = Na+, K+, Mg2+, Ca2+, Zn2+ and hydrated Mg2+ ions) and water molecules on the tautomerism of adenine induced by single intramolecular proton transfer (SPT) have been investigated theoretically. Calculated results show that the single proton transfer process in adenine base is favored and even becomes thermodynamically spontaneous because of the presence of Mn+ interacting at the N3 position of adenine. On the contrary, if Mn+ coordinated to N7 site, the single proton transfer process will become unfavorable than that in the neutral system. The effects of metal ions on the SPT of adenine base are more pronounced if Lewis acidity of metal ion is increased. Water plays a more important role than metal ions during the SPT process. It is found that water can act not only as a solvent but also as a mediator which gives and accepts protons to promote SPT, playing a bridge role. As a result, inclusion of a water molecule drastically reduces the energy barrier for the SPT. Moreover, two water molecules can yield larger assisting effect on the SPTs compared with one water molecule. We can conclude that the tautomerism of DNA adenine base can be modulated by the metal ions and water molecules. Copyright © 2015 John Wiley & Sons, Ltd.

SUMMARYSchistosoma japonicum, a human blood fluke, causes a parasitic disease affecting millions of people in Asia. Thioredoxin–glutathione system ofS. japonicumplays a critical role in maintaining the redox balance in parasite, which is a potential target for development of novel antischistosomal agents. Here we cloned the gene ofS. japonicumthioredoxin (SjTrx), expressed and purified the recombinant SjTrx inEscherichia coli. Functional assay shows that SjTrx catalyses the dithiothreitol (DTT) reduction of insulin disulphide bonds. The coupling assay of SjTrx with its endogenous reductase, thioredoxin glutathione reductase fromS. japonicum(SjTGR), supports its biological function to maintain the redox homeostasis in the cell. Furthermore, the crystal structure of SjTrx in the oxidized state was determined at 2·0 Å resolution, revealing a typical architecture of thioredoxin fold. The structural information of SjTrx provides us important clues for understanding the maintenance function of redox homeostasis inS. japonicumand pathogenesis of this chronic disease.

The direct asymmetric vinylogous Michael addition of 3,5-dialkyl-substituted 4-nitroisoxazoles with α,β-unsaturated aldehydes catalyzed by a diphenylprolinol TBS ether organocatalyst is described, giving products with moderate to good yields and up to excellent enantioselectivities (96% ee). This approach provides an easy access to highly functionalized chiral isoxazole derivatives.

In biological systems, chiral self-assemblies are formed in water. To understand the role of water in the formation of supramolecular chirality, an amino acid derivative, N,N-diphenylalanine-3,4,9,10-perylenetetracarboxylicdiimide (PBI-Phe), was synthesized from perylene-3,4,9,10-tetracarboxylic dianhydride and phenylalanine. PBI-Phe self-assembled into a spherical structure in pure DMSO, but into a helical fiber structure in a solution of DMSO mixed with water. Furthermore, increasing the relative amount of water included in the solution led to an increase the supramolecular chirality.

Described is a visible light-promoted three-component tandem annulation of amines, aryl/alkyl isothiocyanates, and α-bromoesters to form 2-iminothiazolidin-4-ones in the absence of metal and photocatalyst at room temperature. This [1 + 2 + 2] cyclization strategy involves visible light-promoted C–S/C–N bond formation and features a powerful approach to the synthesis of 2-iminothiazolidin-4-ones with broad substrate scope, excellent functional group tolerance, mild reaction conditions, step-economy, and simple operation, which also has potential applications in the pharmaceutical industry. UV–vis spectroscopy indicates that an in situ-generated H-bonding electron donor–acceptor (EDA) complex probably acts as the photocatalyst, facilitating the reaction process.

Photochromic compounds, employing photonic energy for excited-state bond rupture and bond construction processes, are excellent candidates for application as optical molecular information storage devices. In this work, a dispersion corrected density functional theory (DFT-D) study was carried out on the photoisomerization mechanism of the osmium sulfoxide complex, [Os(bpy)2(DMSO)2]2+ (bpy = 2,2′-bipyridine; DMSO = dimethyl sulfoxide), which features a pronounced photochromic character based on an ultrafast photo-triggered linkage isomerization located at the SO-ligand. Calculated results demonstrate that the Os–S → Os–O isomerization proceeds adiabatically on the potential energy surface (PES) of the lowest metal-to-ligand charge transfer excited states 3MLCTS → 3MLCTO, and the metal centered ligand field (3LFS) excited state is not involved. However, attributed to the weakened Os–DMSO bond-strength upon Os–S to Os–O isomerization, the population of the 3LFO excited state is thermally accessible. Therefore, photodissociation of DMSO from the Os center occurs via homolytic cleavage of the Os–O bond after an avoided curve crossing between the lowest 3MLCTO state and the 3LFO repulsive state along the stretching coordinate of the Os–O bond.

Novel three-component hybrid hydrogels have been constructed by amino acid derivatives, riboflavin and melamine through self-assembly. In the process of gelation, the driving forces are attributed to hydrogen bonding and π–π interaction. These luminescent hydrogels demonstrate excellent mechanical strength (>104 Pa) and low cell toxicity, which have been investigated by means of ultraviolet spectra (UV), fluorescence spectra, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM), rheological experiments and cytotoxicity assay. What's more, these hybrid hydrogels could be used to drive the drug release in a controlled manner and be used for promoting E. coli growth, and they accelerate the growth of E. coli distinctly.

The first example of an “on water” direct catalytic vinylogous Henry addition of 3,5-dialkyl-4-nitroisoxazoles to isatins is described, giving products in excellent yields and up to excellent diastereoselectivities. A remarkable rate-enhancement by water was observed under mild conditions. This approach provides a highly efficient and environmentally benign access to medicinally important isoxazole substituted 3-hydroxy-2-oxindole derivatives.

An AIE based tetraphenylethylene derivative (TPPTPE) was synthesized for light-up sensing of ATP in aqueous solution. The measuring range for ATP can be tuned by varying the concentration of the TPPTPE. A one-step straightforward quantitative analysis of the ATP level in cell lysates can be realized using the TPPTPE. Moreover, the TPPTPE can be used for monitoring apyrase activity in aqueous solution and detecting ATP both in living cancer cell lines and in living normal cell lines.

In this article, we study finite-time synchronization of complex network with unknown parameter by applying a new type of sliding form controller. On account of the theory for finite-time control, we introduce a new type of sliding form surface. We testify that the system converge to the zero point in a given finite-time. Then we propose a sliding form controller which guarantee that the sliding movement happen in a finite time. We testify that the sliding form scheme has finite-time stability and convergence.

The implicit space mapping technique is implemented as the optimization algorithm for the reflected group delay method in designing a 6-pole microstrip hairpin filter. A technique is proposed to reduce simulation points by matching a few selected group delay points. A computer-aided EM based design approach is proposed for the integration of the implicit space mapping technique and the reflected group delay method. The design steps are summarized and the filter is designed in Sonnet. By using the proposed method, the computation time and space mapping iterations are significantly reduced.

In this paper, a fast post-fabrication tuning process based on the space mapping technique is proposed for tuning 3D-printed air-filled waveguide filters with fabrication tolerances and insertion loss. The surrogate modelling and parameter extraction processes for postfabricated filters are discussed. The tuning algorithm is presented in detail. To validate the proposed method, it is applied to a metallic air filled X-band iris waveguide filter fabricated using selective laser sintering (SLS) technology. The target filter is fabricated in an irregular process in which it is split into three sections with extra flanges for connection after fabrication. This process significantly reduces the time and cost to fabricate a 5 inch long filter using 3D printing. But it also results in extra alignment tolerances and deteriorated return loss. By applying the tuning algorithm, we are able to significantly improve the return loss in just one iteration.

Globally, vegetable fields are the primary source of greenhouse gas emissions. A closed-chamber method together with gas chromatography was used to measure the fluxes of nitrous oxide (N2O) emissions in typical vegetable fields planted with four vegetables sequentially over time in the same field: endive, lettuce, cabbage and sweet corn. Results showed that N2O fluxes occurred in pulses with the N2O emission peak varying greatly among the crops. In addition, N2O emissions were linearly associated with the nitrogen (N) application rate (r = 0.8878, n = 16). Excessive fertilizer N application resulted in N loss through nitrous oxide gas emitted from the vegetable fields. Compared with a conventional fertilization (N2) treatment, the cumulative N2O emissions decreased significantly in the growing seasons of four plant species from an nitrogen synergist (a nitrification inhibitor, dicyandiamide and biochar treatments by 34.6% and 40.8%, respectively. However, the effects of biochar on reducing N2O emissions became more obvious than that of dicyandiamide over time. The yield-scaled N2O emissions in consecutive growing seasons for four species increased with an increase in the N fertilizer application rate, and with continuous application of N fertilizer. This was especially true for the high N fertilizer treatment that resulted in a risk of yield-scaled N2O emissions. Generally, the additions of dicyandiamide and biochar significantly decreased yield-scaled N2O-N emissions by an average of 45.9% and 45.7%, respectively, compared with N2 treatment from the consecutive four vegetable seasons. The results demonstrated that the addition of dicyandiamide or biochar in combination with application of a rational amount of N could provide the best strategy for the reduction of greenhouse gas emissions in vegetable field in south China.

Bisphenol A (BPA) is used in the production of plastic but has oestrogenic activity. Therefore, BPA substitutes, such as fluorene-9-bisphenol (BHPF), have been introduced for the production of so-called ‘BPA-free' plastics. Here we show that BHPF is released from commercial ‘BPA-free' plastic bottles into drinking water and has anti-oestrogenic effects in mice. We demonstrate that BHPF has anti-oestrogenic activity in vitro and, in an uterotrophic assay in mice, induces low uterine weight, atrophic endometria and causes adverse pregnancy outcomes, even at doses lower than those of BPA for which no observed adverse effect have been reported. Female mice given water containing BHPF released from plastic bottles, have detectable levels of BHPF in serum, low uterine weights and show decreased expressions of oestrogen-responsive genes. We also detect BHPF in the plasma of 7/100 individuals, who regularly drink water from plastic bottles. Our data suggest that BPA substitutes should be tested for anti-oestrogenic activity and call for further study of the toxicological effects of BHPF on human health., Bisphenol A is used in the production of many plastic products, but has adverse health effects and is therefore being replaced. Here the authors show that its substitute, fluorene-9-bisphenol, is released from commercial plastic bottles into drinking water, and has anti-oestrogenic effects in mice.

To investigate the steric effect of amino acids, N,N′-dialanine-1,4,5,8-naphthalene tetracarboxylic acid diethylamide (ANTA) and N,N′-diphenylalanine-1,4,5,8-naphthalene tetracarboxylic acid diethylamide (PNTA) were synthesized based on naphthalene-1,4,5,8-tetracarboxylic dianhydride (NTA) with alanine and phenylalanine, respectively. These compounds were characterized by infrared spectroscopy (IR), magnetic resonance spectroscopy (1H NMR, 13C NMR) and mass spectrometry (MS). Interestingly, ANTA could self-assemble into spiral nanorings, but PNTA formed nanospheres. In order to reveal the self-assembly driving forces, the two-dimensional (2D) supramolecular self-assembly behaviours were studied on highly oriented pyrolytic graphite (HOPG) by scanning tunneling microscopy (STM) at the solid–liquid interface, which indicated the driving forces could be attributed to intermolecular hydrogen-bonding and π–π stacking interactions. These results represent different self-assembly behaviours due to the steric effect of amino acids.

In this work, redox stimulated S → O and O → S isomerization of the bound sulfoxide in [Ru(bpy)(tpy)(dmso)]2+ (bpy = 2,2′-bipyridine; tpy = 2,2′:6′,2′′-terpyridine; dmso = dimethyl sulfoxide) was explored theoretically with dispersion corrected density functional theory to gain an understanding of the electrochromic mechanism of polypyridine ruthenium sulfoxide complexes. It is interesting to note that oxidation and reduction play different roles in the intramolecular isomerization of ruthenium(II) sulfoxide complexes. Potential energy surface (PES) results demonstrate that Ru–S to Ru–O linkage isomerization is more thermodynamically favored in the oxidized state of the Ru2+(S) complex. Differently, reduction of Ru3+(O) or Ru2+(O) complexes makes the Ru–O bond-breaking and Ru–S bond-making reaction much easier. These can be explained by different effects of oxidation and reduction on the energy gap (ΔE) between S, O donors and Ru acceptors, by which Ru–S and Ru–O bond-strengths were determined.

In this study, unique luminescent gels have been obtained from two components between amino acid functionalized perylene derivatives and 4,4'-bipyridyl units via hierarchical self-assembly. The luminescent gels have been investigated by means of ultraviolet spectra (UV), fluorescence spectra, Scanning Electron Microscopy (SEM) and Laser Scanning Confocal Microscopy (LSCM), which illustrate the strong fluorescence intensity of the gels. In order to further reveal the self-assembly driving forces, the two-dimensional (2D) self-assembly behaviours have been studied by scanning tunneling microscopy (STM) on a highly oriented pyrolytic graphite (HOPG) substrate at the solid-liquid interface, which indicates that the driving forces are attributed to the intermolecular hydrogen bonding and π-π stacking interactions. According to the interaction mode, these organogelators are found to rapidly transform from gels to solutions by adding triethylamine.

Electronic and photophysical properties of [Ru(bpy) 2 (OSO)] + (bpy = 2,2′-bipyridine; OSO = methylsulfinylbenzoate) were examined theoretically to better understand the differences between S- and O-linked ruthenium sulfoxide complexes. It is found that the strength of Ru–O 1 linkage is significantly larger than that of Ru–S linkage, which makes the charge transfer amount from surrounding ligands to central Ru decreased. The energy gap is closed due to the highest occupied molecular orbital energy increases to a larger extent than the lowest unoccupied molecular orbital energy. Thereby, red shifted absorption and emission maxima in such photochromic ruthenium sulfoxide complexes can be explained.

The influence of metal cations (Mn+ = Na+, K+, Mg2+, Ca2+, Zn2+) on the single proton transfer process in guanine base has been studied at the MP2/6-31G* and B3LYP/6-311++G** levels of theory. Two main basic binding sites, N3 and N7 of guanine, are considered for Mn+ coordination. It is observed that the tautomerism behavior of guanine, induced by intramolecular single proton transfer, can be modulated by surrounding metal counterions. Calculated results show that the single proton transfer process in guanine is favored and even becomes thermodynamically spontaneous due to the presence of Mn+ interacting at the N3 position of guanine. On the contrary, if Mn+ coordinated to N7 of guanine, the single proton transfer process will become unfavorable than that in the neutral system. Moreover, the effects are more pronounced for the divalent cations than for the monovalent ones. All of them can be understood from the electrostatic and oxidative effects of metal cations on the guanine base obtained from further natural bond orbital (NBO) analyses.

Single basal application of bulk blending urea(BBU) which consists of both controlled-released urea(CRU) and conventional urea(U) has been proposed to facilitate fertilization and lower cost of CRU. Nevertheless, its effect on the growth, yield and N use efficiency(NUE) of rice in double rice cropping system under subtropical environment are still unknown. Field experiments were conducted at two different sites(Taishan county and Wengyuan county) simultaneously in Guangdong province to investigate the effects of single basal application of two types of BBU(P-BBU which consists of parabolic pattern CRU, and S-BBU which consists of sigmodial pattern CRU) on soil available N, grain yield and NUE. Conventional high-yield fertilization treatment with four split applications of U(FP) and no-N treatment(CK) were established as controls. The results demonstrated that BBU could provide similar or more adequate N nutrient for rice with FP during late rice season. BBU performed comparably to or better than FP on soil NH4+-N, dry matter, grain yield and NUE during late rice season. During early rice season, BBU performed comparably with FP on soil NH4+-N, N content of rice, dry matter, grain yield and NUE at Taishan site, while at Wengyuan site, it significantly reduced soil NH4+-N, N content of rice, dry matter and NUE compared with FP, and reduced grain yield slightly. Release tests in water and paddy field were conducted in order to evaluate the releasing dynamics of parabolic and sigmodial pattern CRU. Results showed that the N release rate of CRU in paddy field during early rice season was significantly slower than that during late rice season. This was closely correlated with the changing pattern of accumulated temperature. The N release rate of parabolic CRU in paddy field was faster and more sensitive to changing temperature than sigmodial CRU. Non-linear regression analysis shows that the N release patterns of sigmodial CRU in paddy fields were more close to N uptake of rice during both rice seasons. The grain yield of rice and NUE in S-BBU was higher slightly than P-BBU during both rice seasons. These results demonstrated that BBU obtained similar grain yield in double rice cropping system in South China, and S-BBU treatment is better for N requirement of rice during both seasons. Future studies should focus on optimizing and customizing the blending ratio of BBU for each rice season in double rice cropping system to increase crop yield and the robustness of BBU to changing weather conditions.

Mixed vegetable oil (castor oil and hydroxylated soybean oil, MVO) and polymethylene polyphenylene isocyanate (PPI) has been proposed for the coating layer preparation of MVO-based controlled release fertilizer (MCRF). The physicochemical properties and surface morphology of the layer as well as nutrient release characteristics of MCRF were systematically investigated. It was found that molar ratio of MVO and PPI was negatively correlated to the longevity of MCRF. Incensement of mass percentages (MPs) of MVO and core fertilizer could prolong longevity of MCRF. The longevity of MCRF under MMVO/MPPI ratios of 5:4 with the 3% MP reached a maximum value (164.14 ± 2.45 days). The rough surface with more wrinkles in the layer was negative correlation to the initial release rate of nutrient (IRN). A positive relationship between the rough surface with more wrinkles in the layer and the longevity was also observed. The contact angle and surface energy (SE) of the layer had the most obvious effect on the IRN and longevity, especially SE. The modification of molar ratios of MVO and PPI can be considered as a sustainable and cleaner production measure to regulate the nutrient release of MCRF, which will further improve the application of MVO in the future fertilizer field.

Abnormal levels of the biological thiol cysteine (Cys) have been shown to be associated with growth retardation, skin lesions, and neurotoxicity in humans. In order to fully elucidate the role of Cys in biological systems, its levels must be monitored through in vitro assays as well as in living cells and animals. Herein, we designed and synthesized a novel near-infrared xanthene fluorescence probe (NOF1) with an acrylate group as a trigger moiety to detect Cys over homocysteine and glutathione. The NOF1 probe exhibited a good selectivity and a high sensitivity toward Cys, with a detection limit of 210 nM. Additionally, NOF1 retained good sensitivity and selectivity in human plasma, with a good recovery of Cys within the range 98%–102%. Importantly, the NOF1 probe was successfully applied to the fluorescence imaging of Cys in living cells, zebrafish, and mice, showing great potential for applications involving the detection of Cys both in vitro and in vivo.

The use of controlled release urea (CRU) was proposed as a promising approach to improve crop yield and nitrogen use efficiency (NUE) of crops in varying regions. However, such beneficial effects have not been well assessed in winter oilseed rape (Brassica napus L.), which usually has a period longer than 200 days. In this regional scale study covering 9 site-years, the effects of CRU for oilseed rape (CRUrape) application on seed yield, NUE, N physiological efficiency (NPE) and the recommended application rate were investigated, in comparison with conventional urea (CU). Oilseed rape plants were grown with either CRUrape or CU applications with five N rates (0, 60, 120, 180 and 240 kg N ha−1). The results showed that CRUrape N release coincided well with oilseed rape N demand. The CRUrape application generally increased seed yield relative to CU, and such effects were more pronounced at higher N rates (180 and 240 kg N ha−1) because of the sufficiency N supply over the whole growing season and thus higher pods per plant. While the low N rates (60 and 120 kg N ha−1) could not supply adequate N at early development stage. Obvious N source × N rate interaction was observed. Moreover, the N source × site-year interaction was significant. The yield increase by CRUrape over CU varied considerably among site-year, suggesting CRUrape effects may depend very much on the target environmental conditions. Further analysis revealed that precipitation before wintering and accumulative temperature over the over-wintering contributed to variations in such CRUrape effects. The oil yield was remarkably increased by 12.4% and 7.1% by CRUrape relative to CU at 180 and 240 kg N ha−1, because of the benefits of seed yield and oil concentration. The NUE and NPE of CRUrape were higher than that of CU as the N rate increased to 180 kg N ha−1. The recommended N application rate of CRUrape was different from that of the CU in 5 of 9 site-years. The mean optimal N rate for the region investigated was quite similar for CRUrape and CU (203 and 201 kg N ha−1, respectively), but CRUrape application with optimal N rate could enhance the average grain yield by 7.2% and the related gross profit by 17.8%, respectively. In conclusion, the CRUrape application could be used as a feasible strategy to improve oilseed rape seed yield, oil yield and NUE in the investigated region.

A series of novel self-dispreading phenoxy carboxylic acid derivatives were designed and synthesized by I 2 catalyzed one-step reaction. Their structures were confirmed by IR, NMR, and HRMS. The derivatives can self-spread and float on the water surface. Preliminary bioassays showed that some compounds, 3i – 3p , had excellent herbicidal activities against water hyacinth. This strategy provided a novel approach for the water hyacinth control.

Thioredoxin glutathione reductase from Schistosoma japonicum (SjTGR), a multifunctional enzyme, plays a vital role in antioxidant pathways and is considered to be a potential drug target for the development of antischistosomal chemotherapy. In this study, two constructs of a truncated form of SjTGR without the last two residues (Sec597-Gly598) were cloned, overexpressed and purified using wild-type and codon-optimized genes. Only SjTGR from the wild-type gene was found to form a complex with flavin adenine dinucleotide (FAD), which could be crystallized in the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 84.185, b = 86.47, c = 183.164 Å, at 295 K using the hanging-drop vapour-diffusion method. One dimer was present in the crystallographic asymmetric unit and the calculated Matthews coefficient (VM) and solvent content were 2.6 Å(3) Da(-1) and 52.8%, respectively. Structural determination of SjTGR is in progress using the molecular-replacement method.

Polyfunctional molecules, 1,5-enynes, have been achieved via a palladium(0)-catalyzed domino coupling reaction of (Z)-β-bromostyrenes with norbornenes in the presence of cesium carbonate and N,N-dimethylformamide. The process involves a double Heck-type procedure, two-fold C(sp2)H activation and formation of two carbon-carbon bonds. There are possibilities of diversified transformation for the domino coupling of (Z)-β-bromostyrenes with norbornenes, the procedure is successfully driven to 1,5-enynes via accurate adjustment of the reaction conditions.

In this study, we report a novel three-component luminescent hydrogel, which is composed of amino acid derivatives (N,N′-di valine-3,4,9,10-perylenetetracarboxylic acid, NVPD), riboflavin (RF), and melamine (MM). The three-component hydrogel is attributed to multiple hydrogen bonds and the strong π-π stacking interaction between these molecules. Based on the strong hydrogen bonding of the gelator, when the reversible process between the gel and the solution take places it changes the pH of the system from 6.1 to 10.6. In addition, green fluorescence could be the emissive of the hydrogel under 498 nm and the conversion process of the aggregation state repeated reversibly by altering the value of ambient pH. This pH-responsive luminescent gel may display potential for use in nano pH sensors.

Here, we use dispersion-corrected density functional theory methods to illustrate how it is possible to control the electronic and photophysical properties of [Ru(bpy)2(OSO)]+ (bpy = 2,2′-bipyridine; OSO = methylsulfinylbenzoate) isomers with the type and positions of the substituents on coordinated ligand. It is found that the frontier MOs of the ruthenium sulfoxide complexes can be substantially modulated as a function of different substitution patterns. Correspondingly, the first absorption and phosphorescence emission transitions can be tuned because both of them are dominated by one-electron transitions between frontier MOs. More importantly, the relative thermodynamic stabilities of two linkage isomers also can be changed with ligand modification. It is proposed that the Ru–S → Ru–O1 isomerization is more thermodynamically favored by electron-withdrawing group substitution on coordinated ligands. Understanding the variation of electronic and photophysical properties induced by ligand modification can be used for developing a rational design process for such electrochromic materials.

MicroRNAs (miRNAs) family members are usually different from each other in one-base variation. The high sequence homology poses a challenge for miRNA analysis with single-base selectivity. On the basis of G-quadruplex molecular beacons (G4MB) and duplex-specific nuclease (DSN), we developed a simple and highly selective amplification biosensor for miRNA detection. G4MB with a G4 motif stem is used as recognition probe. In the present of target miRNAs, G4MB hybridizes with target miRNA perfectly and forms a G4MB-miRNA duplex. Then, DSN subsequently cleaves the G4MB of the G4MB-miRNA duplex to recycle the target miRNA, which leads to fluorescence signal amplification. In the absence of target miRNAs, DSN can not digest the stem of G4MB because of the protection of G4 motif, which eliminates the false positive signal, and produces low fluorescence background. Importantly, the powerful discriminating abilities of both G4MB and DSN make the novel sensor suitable for miRNAs detection with high single-base selectivity. Comparing with traditional linear ssDNA probe-DSN-based method, the signal response of similar miRNA sequences with one-base difference has been reduced from 24% to 6% by using this G4MB-DSN-based method. Moreover, this simple sensor also exhibits a good applicability in cancer cell samples and a multiplex capability in one sample with different miRNA targets, making it a promising strategy for clinical diagnostics.

In this paper, a class of discrete SEIRS epidemic models with general nonlinear incidence is investigated. Particularly, a discrete SEIRS epidemic model with standard incidence is also considered. The positivity and boundedness of solutions with positive initial conditions are obtained. It is shown that if the basic reproduction number \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\mathcal{R}_{0}\leq1$\end{document}R0≤1, then disease-free equilibrium is globally attractive, and if \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\mathcal{R}_{0}> 1$\end{document}R0>1, then the disease is permanent. When the model degenerates into SEIR model, it is proved that if \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\mathcal{R}_{0}> 1$\end{document}R0>1, then the model has a unique endemic equilibrium, which is globally attractive. Furthermore, the numerical examples verify an important open problem that when \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\mathcal{R}_{0}>1$\end{document}R0>1, the endemic equilibrium of general SEIRS models is also globally attractive.

A novel three-component supramolecular hydrogel based on riboflavin, melamine and amino acid derivatives were constructed for controlled release of pesticides, Niclosamide derivatives. The formation of hydrogel may be attributed to self-assemble via hydrogen bonding and π-π interaction, which have been researched via scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectra. The rheological experiments showed that the hydrogel materials and drug-loaded hydrogel all demonstrated good mechanical strength and high stability. Further experimental results indicated that the drug-loaded hydrogels show large drug loadings, long-term release time and relatively higher efficiency to anti-cercariae in the water environment.

The hemocyanin of Oncomelania hupensis (OhH) is essential for the survival of O. hupensis and may be an effective target for the development of new molluscicide. 4-(Chloroacetyl)catechol is a substrate analogue of OhH. In this study, we evaluated the toxicity of 4-(chloroacetyl)catechol to O. hupensis and Kunming mice. 4-(Chloroacetyl)catechol had strong molluscicidal activities and the molluscicidal activities was time and dose-dependent. With the increase of exposure time, the LC50 values of the 4-(chloroacetyl)catechol decreased from 6.5 mg/L (24 h) to 3.1 mg/L (72 h). The LC90 values decreased from 16.4 mg/L (24 h) to 4.9 mg/L (72 h). In the acute toxicity test of mice, no evident poisoning symptoms and no animal death were detected after 14 days’ continuous observation, which indicated that 4-(chloroacetyl)catechol was a low toxic substance for Kunming mice. These results indicated that 4-(chloroacetyl)catechol is potent molluscicides.

Three new Z-shaped supramolecular complexes (C44H28N4Zn)2·(C14H14N4O2)·(C6H5Cl)4 (1), (C44H28N4Zn)2·(C14H14N4O2)·(CH2ClCH2Cl)2·(H2O)4 (2), and (C32H16N8Zn)2·(C14H14N4O2)·(DMF)4 (3) have been prepared by Zinc tetraphenylporphyrin(ZnTPP) and/or Zinc phthalocyanine(ZnPc) with bis(pyridyl) ligands (pyCH2NHCOCONHCH2py, py = 3 or 4-pyridyl), which are ditopic ‘Z’ type ligands. In all of the complexes the central Zn atom is equatorially coordinated by four isoindole N atoms of Pc or TPP macrocycle and axially by N atom of bis(pyridyl) ligands. The interaction of the central Zn atom of ZnTPP and ZnPc with the axial N atom of bis(pyridyl) molecule leads to a deviation of Zn from the basal plane towards the bis(pyridyl) ligands by 0.2 A in complexes 1–3. The electronic absorption spectra and fluorescence spectra reveal that all of the three supramolecular complexes have a blue-shift and display strong fluorescence.

Hemocyanin, a giant oxygen transport protein which is usually found in many arthropods and mollusks was isolated and purified from Oncomelania hupensis. In this study, we showed that Oncomelania hupensis hemocyanin (OhH) shared carbohydrate epitopes with different developmental stages of Schistosoma japonicum (Cercaria, Schistosomulum, Adult worm and Egg) and exhibited serological cross-reaction with these stages of S. japonicum immune sera, which had a potential for use in diagnostic and therapeutic studies of schistosomasis. OhH was used as a vaccine in combination with Freund's adjuvant to evaluate the induction of immune responses and protection against S. japonicum infection in mice. Mice immunized with OhH induced a Th1 type of immune responses. Strong protection against S. japonicum were observed in adult worm and egg burdens after 42 days post-challenge, which showed a significant worm reduction of 52.5% and egg reduction of 69.2% compared to the control groups, respectively. These results indicated that OhH was a potential candidate to compose an anti-schistosome vaccine.

Two novel niclosamide derivatives were synthesized by adding polyethylene glycol groups of differing lengths to a niclosamide core. The modified niclosamide derivatives were characterized using 1 H NMR and HRMS spectra. Anti-cercarial bioactivity results showed that the niclosamide derivative constructed to float on the surface of the water was able to kill cercariae when the number of hydrophilic groups was >3. A fluorescent niclosamide derivative containing naphthalimide was further synthesized to observe the interaction between the cercaricide and Schistosoma japonicum cercariae. Confocal fluorescence microscopy revealed that the fluorescent niclosamide derivative could easily penetrate into the cercarial body beyond the circulatory system leading to the rapid death of cercariae.

The electron–phonon scattering of phosphorene is investigated via performing first-principles calculations. Our results reveal that the scattering rates are negligible at the valence band maximum (VBM) and conduction band minimum, but they are much larger away from the band edges. The scattering rates increase with the rising temperature. The relaxation times run up to ~850 fs around the VBM at 1 K, and they will decrease with the increasing temperature. In addition, we find that the mean free paths (MFPs) are anisotropic. The MFPs along the armchair direction are two times larger than that along the zigzag direction near the band edges. According to our results, we predict that the extraction of hot holes is best achieved along the armchair direction in phosphorene with a 65 nm range at 1 K. The best extraction range of hot electrons is less than 30 nm along the armchair direction at 1 K. On the other hand, the extraction range of hot holes and hot electrons will decrease to 15 nm along both directions in phosphorene at 300 K.

The gastropod mollusc, Oncomelania hupensis is a unique intermediate host for the human parasite Schistosoma japonicum. It is a primary factor for the epidemic of schistosomiasis and its distribution is consistent with the epidemic area of schistosomiasis. Here we report the functional properties of hemocyanin of O. hupensis (OhH), a copper-containing respiratory protein which was isolated from its hemolymph and purified by ammonium sulfate fractionation and ultracentrifugation. We identified the protein characters including UV absorption at 340 nm, copper content and quaternary structure. Furthermore, by induction of phenoloxidase and enzyme-linked immunosorbent assay we show that OhH exhibited o-diphenoloxidase activity after limited proteolysis, and shared carbohydrate epitopes with glycoconjugates of S. japonicum.