Search

The purpose of this article is to research the existence of solutions for fractional periodic boundary value problems with $ p\left(t \right) $-Laplacian operator. In this regard, the article needs to establish a continuation theorem corresponding to the above problem. By applying the continuation theorem, a new existence result for the problem is obtained, which enriches existing literature. In addition, we provide an example to verify the main result.

A metal- and oxidant-free three-component desulfurization and deamination condensation of amidines, isothiocyanates, and hydrazines for the synthesis of structurally diverse fully substituted 1H-1,2,4-triazol-3-amines is described. The reaction proceeds without the requirement of any external catalysts, metals, ligands, or oxidants. This [2 + 1 + 2] cyclization strategy involves C-N and C-S bond cleavage and the formation of new C-N bonds in one pot. This transformation provides a series of full substituted 1H-1,2,4-triazol-3-amines with advantages of a broad substrates scope, mild reaction conditions, environmental friendliness, and easy gram-scale applications. The fluorescence and aggregation-induced emission (AIE) properties of selected products were further tested. These synthesized 1H-1,2,4-triazol-3-amines may be worth investigating for further applications in the fields of organic chemistry, medicinal chemistry, and optical materials.

Background Blast lung injury (BLI) has been one of the most threat for human beings with the frequent occurrence of local wars, terrorist attacks and industrial explosions. The underlying mechanisms remains unclear. In this paper, transcriptome sequencing was performed in the lung tissues of the two species of goat and rat to identify the potential therapeutic targets involved in BLI. Results In this paper, the BLI models of rat and goat were successfully by validated HE-stain. Reddish edema fluid, erythrocyte, and even focal or patchy bleeding occurred in the alveolar cavity were visible under microscope. The genomic information of the two species was obtained by transcriptome sequencing. There were 83 DEGs co-expressed in rats and goats, among which 49 genes showed the same expression trend, including 38 up-regulated expression genes and 11 down-regulated expression genes. By the enrichment analysis, IL-17 signaling pathway and vascular smooth muscle contraction pathway are involved in BLI mechanism. The genes expressed in lung were screened for experimental verification, the main genes associated with BLI in both goat and rat are AGR2, ANKRD65, BPIFA1, BPIFB1 and KRT4. Conclusion In this study, the whole genomes of two species of BLI models were sequenced to dissect the basic characteristics of their genomes, laying the foundation for further investigation the mechanisms of BLI. By the genomic analysis, the expressed genes were involved in IL-17 signaling pathway and vascular smooth muscle contraction pathway associated with BLI. Finally, AGR2, ANKRD65, BPIFA1, BPIFB1 and KRT4 were highly expressed in both goat and rat BLI model, which could be used as potential target genes and may serve as biomarkers for the prognosis, diagnosis and therapy for BLI.

Schistosomiasis, a neglected tropical disease (NTD), is one of the most prevalent parasitoses in the World. Certain freshwater snail species are the intermediate host in the life cycle of schistosome species. Controlling snails employing molluscicides is an effective, quick, and convenient intervention strategy to prevent the spread of Schistosoma species in endemic regions. Advances have been made in developing both synthetic molluscicides and molluscicides derived from plants. However, at present, the development of molluscicides is not adapted to the actual demand for snails and schistosoma controlling. We undertake a systematic review of exploitation and application of synthetic molluscicides and molluscicides derived from plants to combat intermediate host snails. The detailed molluscicidal activity, structure–activity relationship, structural feature, and possible mechanism of some molluscicides are also highlighted, which may afford an important reference for the design of new, more effective molluscicides with low environmental impact and realize the aim of controlling schistosome at transmission stages. Supplementary Information The online version contains supplementary material available at 10.1007/s00436-021-07288-4.

A new photocatalyst-free visible-light-enhanced strategy for the synthesis of pyrazolo[1,5-a][1,3,5]triazine-2,4-diamines via the formation of electron donor-acceptor (EDA) complexes is reported. The in situ generated pyrazolthiourea intermediates from 1H-pyrazol-3-amines and isothiocyanates undergo formal [4 + 2] annulation with 1,1,3,3-tetramethylguanidines (TMG) to deliver the corresponding products involved in three C-N bond formations in a one-pot protocol. The formation of EDA complex from pyrazolthiourea and TMG is confirmed by UV-vis spectroscopy and 1H NMR experiments. Moreover, this mild reaction proceeds in the absence of any external transition metals, oxidants, bases, and ligands. This efficient methodology for the synthesis of purine analogues pyrazolo[1,5-a][1,3,5]triazine-2,4-diamines provides potential synthetic applications in the field of drug research and development.

Novel lignin/paraffin/epoxy resin composite coated urea (LPECCU) was successfully prepared. Paraffin and epoxy resin (ER) were used to improve the slow-release properties of the lignin-based polyurethane (LPU) coated urea. The relationships among the N release characteristics, liquid-solid rate, -CNO/-OH molar rate and film formation rate in the coating material of LPECCU were investigated. The results showed that the water contact angle (WCA) of the LPU-paraffin increased with the rate of liquid-solid rate (73.61-88.19°) and -CNO/-OH molar rate (65.17-82.24°) increased. The average particle hardness of LPECCU decreased with the increased of liquid-solid rate (57.10-66.80 N) and the reduced of -CNO/-OH molar rate (48.11-63.00 N). The LPECCU emerged compact micro-structure, low sustained release and high compressive resistance by adding paraffin and ER. The coating material of LPECCU appeared excellent biodegradability in the soil. The optimal N cumulative release rate (72.49 %) of LPECCU was obtained (liquid-solid rate of 1.43, -CNO/-OH molar rate of 2, and the film formation rate of 6.66 %). The lettuce growth study was conducted to further evaluate the pot application of the LPECCU. In comparison to conventional urea, LPECCU could improve the total dry matter accumulation and N use efficiency of the lettuce.

Ecological toxicity assessments of contaminants in aquatic environments are of great concern. However, a dilemma in ecological toxicity assessments often arises when linking the effects found in model animals in the laboratory and the phenomena observed in wild fishes in the field due to species differences. Chinese medaka (Oryzias sinensis), widely distributed in East Asia, is a satisfactory model animal to assess aquatic environment in China. Here, we domesticated this species and assembled its genome (814 Mb) using next-generation sequencing (NGS). A total of 21,922 high-confidence genes with 41,306 transcripts were obtained and annotated, and their expression patterns in tissues were determined by RNA-sequencing. Six mostly sensitive biomarker genes, including vtg1, vtg3, vtg6, zp3a.2, zp2l1, and zp2.3 to estrogen exposure were screened and validated in the fish exposed to concentrations of estrone (E

Hydrazonamides are fundamental building blocks in many pharmaceuticals and agricultural chemicals. Although previous transformations have been accomplished through multi-step reactions under harsh conditions, developing highly efficient synthetic strategies remains challenging. Considering the structural characteristic of hydrazonamides, a sequential multi-component reaction of β-ketonitriles with N,N-disubstituted hydrazines is designed and developed through a photocatalyzed intermolecular amination process. This work reports the first example of the use of N,N-disubstituted hydrazines as two different “amine” sources, characterized by isotope labeling experiments. The C–CN/N–N bonds are cleaved and new C–N/CN bonds are constructed in a one-pot reaction. This protocol can be carried out without the addition of any external metals, ligands, bases, oxidants and reductants, and possesses the advantages of operational simplicity, mild reaction conditions, and good functional group tolerance. Furthermore, this approach enables late-stage modifications of structurally complex bioactive molecules, natural products and drugs, thus showing potential applications in the field of organo-pharmaceutical chemistry.

Blast lung injury (BLI) is the major cause of death in explosion-derived shock waves; however, the mechanisms of BLI are not well understood. To identify the time-dependent manner of BLI, a model of lung injury of rats induced by shock waves was established by a fuel air explosive. The model was evaluated by hematoxylin and eosin staining and pathological score. The inflammation and oxidative stress of lung injury were also investigated. The pathological scores of rats' lung injury at 2 h, 24 h, 3 days, and 7 days post-blast were 9.75±2.96, 13.00±1.85, 8.50±1.51, and 4.00±1.41, respectively, which were significantly increased compared with those in the control group (1.13±0.64; P

A procedure for diagnosis and tuning of fabricated bandpass filters is presented. A surrogate model consisting of a mapped coarse model at a basis point and a mapping of measured response with respect to the change of tuning elements from the basis point is established. To reduce the possibility of nonuniqueness, an implicit multipoint parameter-extraction technique is exploited to match both the response and the first-order derivative of response in terms of tuning parameters in the two models. With this approach, the robustness of the surrogate model and the iteration convergence are significantly improved. To verify the proposed method, two screw-tuned waveguide filters, including an ${X}$ -band filter fabricated by computerized numerical control (CNC) technology and a 3-D-printed metallic air-filled filter with large alignment tolerance and surface roughness, are given. To test the robustness of this approach, an FR-4 microstrip combline filter with uncertain dielectric properties is tuned by active varactors for different specifications utilizing the same surrogate model. All testing results achieve sufficient satisfaction to expectation.

Photocages can provide spatial and temporal control to accurately release the various chemicals and bioactive groups when excited by light. Although the absorption spectra of most photocages are in the ultraviolet absorption region, only a few absorb in the visible or near-infrared region. Blebbistatin (

Background: Currently, there are few reports about the sustained-release time of single-layer non-modified lignin-based coated urea that meets the sustained-release standard. Therefore, the unmodified lignin-based material by adding a hydrophobic polymer can improve the hydrophobicity of the coating material.Results: A novel green double layer coating with lignin-based polyurethane (LPU) as the inner coating and epoxy resin (EP) as the outer coating was effectively constructed for coated urea. Fourier transform infrared spectra confirmed that lignin and polycaprolactone diol successfully reacted with Hexamethylene diisocyanate. The loss weight and water contact angle (WCA, 75.6-63.6°) of the LPUs decreased with the increased lignin content. The average particle hardness of the LDCU first increased from 58.1 N (lignin of 30%) to 67.0 N (lignin of 60%), but then decreased to 62.3 N (lignin of 70%). The release longevity of the coated urea was closely related to the preparation parameters of the coating material. The optimal cumulative nutrient release rate (79.4%) of LDCU was obtained (lignin of 50%, -CNO/-OH molar ratios of 1.15, EP of 35%, and coating ratio of 5%). The aggregates of hydrone on the LDCU caused the dissolution and swelling of nutrients, and then the diffusion of nutrients through the concentration gradient. Conclusion: Although the nutrient release of the LDCUs was affected by many factors, the successful development of the LDCUs will improve the rapid development of the coated fertilizer industry.

In this paper, a class of fractional deterministic and stochastic susceptible-infected-removed- susceptible (SIRS) epidemic models with vaccination is proposed. For the fractional deterministic SIRS epidemic model, the existence of solution and the stability of equilibrium points are analyzed by using dynamic method. Then, the appropriate controls are established to effectively control the disease and eliminate it. On this basis, the fractional stochastic SIRS epidemic model with vaccination is further considered, and a numerical approximation method is proposed. The correctness of the conclusion is verified by numerical simulation.

A metal- and oxidant-free three-component desulfurization and deamination condensation of amidines, isothiocyanates, and hydrazines for the synthesis of structurally diverse fully substituted 1

Big data with timestamps can be constructed as the temporal networks. The bursting cohesive subgraphs (BCS) in temporal networks satisfy to accumulate their cohesiveness at the fastest ratio and could be represented as the emergency events. Yet, existing methods demand BCS to last for at least one given time, which neglects the timeliness of BCS and avoids the events being discovered earlier. In this paper, we design the early bursting cohesive subgraphs (EBCS) model based on -core to enable identifying the events as soon as possible. In particular, we first traverse the temporal network into a node-weighted graph by integrating the topological and historical temporal information. To find the EBCS, (1) we propose a global search algorithm, called GS-EBCS, which can find the exact EBCS by iteratively removing the nodes with the lowest weight and maintaining the topological constraints; (2) we further propose a local search algorithm, called LS-EBCS, which exploits the expand-refine idea. Specifically, it first expands the subgraph from the nodes with the largest weight, and then refines the discovered subgraph to satisfy the constraints of EBCS, whose runtime is proportional to the result subgraph. Extensive experiments are conducted on three real temporal networks, which demonstrate the efficiency and effectiveness of our proposed algorithms.

Thiophenol (or PhSH) is widely utilized for producing pesticides, dyes, and pharmaceuticals. However, high-concentration thiophenol not only has adverse effects on living organisms, but also causes environment pollution. Herein, we designed and synthesized a novel near-infrared (NIR) xanthene-based fluorescent probe (NOF) for real-time detection of thiophenol in vitro and in vivo. The probe NOF had good sensitivity and selectivity, and a fast response towards thiophenol. The thiophenol-sensing mechanism was verified using high resolution mass spectroscopy (HR-MS) and density functional theory (DFT) calculation. The probe NOF was also successfully applied to detect thiophenol in real water samples. Finally, owing to its NIR-emitting properties, it was successfully used for NIR fluorescence imaging of thiophenol in living cells and mice.

With the spread of banana Fusarium wilt and the aggravation of the damage, it has become the biggest threat to the banana industry. Many studies have shown that bio-organic fertilizer plays an important role in the prevention and control of banana wilt, but most studies focused on biocontrol bacterium screening, not screening carbon sources that could prevent banana wilt, which lead to organic fertilizer fertilization without better effect. So that, a pot culture experiment (I) with inoculating Fusarium oxysporum f. sp. Cubense (FOC) on bananas was carried out to screen the carbon sources, and d-malic acid (CS2) to prevent and control banana wilt had been screened out by Biolog technology and Principal Component Analysis of microbial community level physiological profiling. To verify application effects of CS2, another banana pot experiment (II) with FOC inoculation had been done. The results showed that: (1) CS2 can effectively improve the activity of soil microorganisms. (2) CS2 can significantly reduce FOC population in soil, and the FOC population treated with CS2 was respectively lower than that treated with control carbon source (CS1) and without carbon source (CK1) 48% and 59%. (3) The banana wilt infection rate and disease index of CS2 treatment were significantly smaller than those of CS1 and CK1. (4) CS2 can promote the growth and biomass accumulation of bananas in pathogenic soil. In conclusion, the screening technology studied here can be applied to screen out the carbon sources for prevention of banana Fusarium wilt, which has great significance to the improvement of prevention effect of biological organic fertilizers to banana wilt.

Thiol-containing amino acids, cysteine (Cys) and homocysteine (Hcy), play crucial roles in the biosystem; their abnormal contents in the cells are linked to many diseases. Herein, we designed and synthesized a novel near-infrared (NIR) phosphorescent iridium(iii) complex-based probe (FNO1) that can detect Cys and Hcy in real-time in the biosystem. Due to the advantages of the iridium complex, the FNO1 probe had excellent chemical stability and photostability, high luminescence efficiency, and long luminescence lifetime. In addition, the probe showed a fast response, high sensitivity, and low cytotoxicity. As verified by high resolution mass spectra (HR-MS) and density functional theory (DFT) calculations, the detection was achieved through the addition of the α,β-unsaturated ketone group in FNO1 by the nucleophilic thiol group in Cys and Hcy. Through time-resolved emission spectroscopy (TRES) and in the presence of a strongly fluorescent dye rhodamine B, the FNO1 probe could detect Cys and Hcy due to its long luminescence lifetime (260/197 ns). Finally, owing to its NIR-emitting properties, the FNO1 probe was successfully applied in the imaging of Cys and Hcy in living cells, zebrafish, and mice.

A visible-light catalyzed [3 + 1 + 2] annulation for the synthesis of unsymmetrical trisubstituted amino-1,3,5-triazines from amidines, isothiocyanates, and 1,1,3,3-tetramethylguanidines has been developed. This method exhibits the advantages of easily available starting materials, insensitive to air and moisture, wide substrate scopes, high step economy, mild, metal- and ligand-free conditions, which has potential applications in the organic, medicinal, and material chemistry.

The photodriven direct C-C/C-N bond formation initiated by electron donor-acceptor (EDA) complexes for the synthesis of indoles has been accomplished via [3+2] annulations of secondary arylamines with alkynes using IC

Quantifying the effects of the intermolecular noncovalent interactions between substrates and reaction environments on the free energy barriers (FEBs) of both enzymatic and solution reactions is vi...

A novel and efficient three-component coupling annulation strategy for the synthesis of 2-iminothiazolidin-4-ones from amines, isothiocyanates, and alkyl acetylenedicarboxylates under visible-light irradiation conditions has been demonstrated. In this transformation, the in situ formed photoactive electron donor-acceptor (EDA) complexes facilitate the reaction and smoothly generate the corresponding products with a high adaptability under mild conditions. This protocol provides a cost-efficient and practical route to 2-iminothiazolidin-4-ones and promotes potential applications on the synthetic drugs.

Elastic and water stable macroaggregate are significant to soil structure. which is the base of the soil, to maintain sustainable agriculture. Whether and how functional amendment fertilizer is capable of construction of the macroaggregate is the main purpose of the study. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to investigate the effect of dolomite-based functional soil amendment fertilizers on soil structure. The fertilizers are beneficial to elastic-stable and water-stable aggregate construction. Calcined dolomite based soil amendment functional fertilizer (CDFF) was favorable to water-stable aggregates. The elastic-stable macroaggregate increased with lime, uncalcined dolomite based soil amendment functional fertilizer (UCDFF) and CDFF, and it was 3.0 to 4.2 times the microaggregate. The water-stable one of the CDFF was increased by 20.0%. The mean weight diameter (MWD) of the CDFF and the UCDFF increased by 0.05~0.19 mm, while that of lime only increased by 0.05 mm. The percentage of aggregate dispersion (PAD) of the CDFF was the least. SEM and EDS images revealed that Fe, Al, Si, Ca, Mg, C and O existed on the aggregates. The construction of stable aggregate lies in that the functional fertilizers can gradually neutralize soil H+ and prevent soil colloid dispersion. Soil particles are bounded together to construct micro-agglomerates and then macro-agglomerates through Ca2+, Mg2+ bond bridge and CaCO3, MgCO3 salt bridge and adhesion of SiO2, Fe2O3, Al2O3 as well as the other amorphous substances from the functional fertilizers.

An efficient space-mapping-based tuning software system is implemented with a user-friendly GUI in Matlab for the automated filter tuning process. The proposed software system is integrated into a tuning system for achieving fast and reliable filter tuning. In this paper, a postfabrication bandpass filter is given to validate the tuning performance of the SMT software system.

A new photocatalyst-free visible-light-enhanced strategy for the synthesis of pyrazolo[1,5

Polycyclic aromatic hydrocarbons (PAHs) are the most common contaminants in the air pollutants. Inhalation exposure to PAHs could increase the risk of respiratory disease, cardiovascular disease and even cancer. However, the biotoxicity of multi-component PAHs from atmospheric pollutants has been poorly studies. The main topic of this study was to investigate the PAHs mixture, which derived from atmospheric pollutants, induced toxic effects and inflammatory effects on human bronchial epithelial cells in vitro. The results showed that PAHs mixture could decrease the cell viability, increase the apoptosis rate, and induce cell cycle arrest at S-phase. Furthermore, the expression of inflammatory factors IL-1β and IL-6 were increased and NF-κB signaling pathway was activated in PAHs mixture-treated cells. The findings of this study indicate that PAHs mixture-induced cytotoxicity and inflammation may be related to intracellular ROS generation and to the activated NF-κB signaling pathway.

2-fluoro-deschloroketamine (FDCK) is a ketamine (KET) analog and new psychoactive substance that has appeared on the drug market in Europe and China in the past few years. The substance has been recently listed as a controlled drug by the narcotics control authority of China. In this work, FDCK and its metabolite nor-fluoro-deschloroketmaine (N-FDCK) in wastewater were analyzed for the first time to monitor FDCK abuse in a southern Chinese province that used to be a major producer and consumer of ketamine. For comparison, KET and its metabolite, nor-ketamine (N-KET) were monitored simultaneously. The concentration ratios between FDCK and N-FDCK were not statistically different from those of KET and N-KET. The average FDCK loads in the province in 2019 were higher than KET loads in most major cities in China in 2014 (when KET abuse hit its peak in the country). Rough estimation of FDCK and KET consumption revealed that FDCK was the predominant synthetic drug in the province in 2019, indicating rapid spread of the substance since its first appearance on the market. FDCK consumption decreased dramatically in 2020 and 2021, due to proactive actions by the local drug police before its listing as a controlled drug. Despite the dramatic decrease, FDCK was still the drug with greatest consumption by 2021, indicating that this substance persisted on the market even in the presence of forceful law enforcement. This finding also demonstrates that this substance may indeed have similar or even improved psychoactive effects relative to KET. Quick spread and persistence of FDCK demonstrated here indicates the urgent need to conduct wastewater-based monitoring of the abuse of the substance in other Chinese provinces and other countries.

Synthetic cannabinoids (SCs) could pose serious health risks to its users. It is necessary to monitor its community consumption. Wastewater-based epidemiology is a potentially useful approach in this regard. However, limited research has been conducted to investigate the occurrence of SCs in wastewater. In this study, liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was optimized to analyze 8 SCs and metabolites (in total 16 analytes) in wastewater. The limit of quantification for this method for certain analytes in wastewater was as low as 0.03 ng L

For volume measurement problems in the processes of additive manufacturing, a volume measurement method is proposed through using the SGBM algorithm in this paper. In this method, the internal and external parameters of the camera are calibrated by the binocular vision system. And the image processes by SGBM are performed for the image acquired by binocular stereo vision system. The processes are including filtering, correction and stereo matching to obtain the disparity information of the object to be tested in the left and right cameras. The volume of the work-piece to be tested can be obtained by the calculation that measured the three-dimensional coordinate information through the disparity information. The experimental results illustrate that the method is of certain reliability and accuracy for volume measurement.

An automated EM-based method for efficient spiral inductor design is proposed and implemented using Matlab-driven Sonnet em simulator. In the proposed method, a surrogate model is established as a replacement to the computational expensive EM model utilizing a one-step calibrated circuit model and an iterative response correction process. In the design procedure, only one parameter extraction is performed prior to the iterative response correction in which no further parameter extraction is required. A hexdecagon spiral inductor is designed and optimized automatically following the proposed procedure, the algorithm convergent within 4 iterations to satisfy design specifications. A comparison between the fine model and updated surrogate model is also given as a validation to the reliability of the proposed method.

Purpose Blast lung injury (BLI) is the most common damage resulted from explosion-derived shock wave in military, terrorism and industrial accidents. However, the molecular mechanisms underlying BLI induced by shock wave are still unclear. Methods In this study, a goat BLI model was established by a fuel air explosive power. The key genes involved in were identified. The goats of the experimental group were fixed on the edge of the explosion cloud, while the goats of the control group were 3 km far away from the explosive environment. After successful modeling for 24 h, all the goats were sacrificed and the lung tissue was harvested for histopathological observation and RNA sequencing. Gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analysis were performed to identify the main enriched biological functions of differentially expressed genes (DEGs). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify the consistency of gene expression. Results Of the sampled goat lungs, 895 genes were identified to be significantly differentially expressed, and they were involved in 52 significantly enriched GO categories. KEGG analysis revealed that DEGs were highly enriched in 26 pathways, such as cytokine-cytokine receptor interaction, antifolate resistance, arachidonic acid metabolism, amoebiasis and bile secretion, JAK-STAT, and IL-17 signaling pathway. Furthermore, 15 key DEGs involved in the biological processes of BLI were confirmed by qRT-PCR, and the results were consistent with RNA sequencing. Conclusion Gene expression profiling provide a better understanding of the molecular mechanisms of BLI, which will help to set strategy for treating lung injury and preventing secondary lung injury induced by shock wave.

The synthesis of N-heterocycles is one of the most active areas due to their structures with extensive applications in the fields of organic, pharmaceutical and materials chemistry. It is an increasingly challenging task to develop greener, milder and cheaper N-heterocycle synthetic strategies through C–N/C–C bond formation owing to the requirement of multistep reactions or harsh reaction conditions in many cases. Herein, this review focuses on the synthesis of N-containing heterocycles such as pyrimidines, imidazoles, 1,2,4-triazoles, 1,3,5-triazines, benzimidazoles, isoquinolines, quinazolines, quinazolinones, 1,2,4-oxadiazoles, thiazoles, and thiadiazoles using amidines as readily available starting materials, with an emphasis on the novel green synthetic methodologies via C–N/C–C bond formation, as well as the mechanisms of these reactions. We hope that this review will help as a reference for researchers who are fascinated with the increasing applications in this prolific area.

A highly selective and red emissive fluorescent probe (HCyNB) for penicillin G amidase (PGA) has been prepared in a simple two-step process. After enzymatic reaction, HCyNB showed a fast response to PGA and afforded a light-up red fluorescence assay of PGA with a detection limit of 0.067 U L−1, without interference from other biologically-relevant species and enzymes, including ROS. The easy synthesis, fast response, good sensitivity, remarkable selectivity and pH independence render HCyNB an outstanding tool for bioimaging of endogenous PGA in penicillinase-producing Bacillus subtilis.

High sequence homology among miRNA members challenges miRNA analysis. In this paper, we developed a simple and highly selective method based on a novel G-triplex molecular beacon (MBG3) and duplex-specific nuclease signal amplification (DSNSA) for miRNA detection. Herein, this MBG3 is a label-free molecular beacon with a special G-triplex probe. The excellent controllablity of the G-triplex probe allowed our MBG3 to have a short stem, which protected it from DSN digestion. Therefore, DSN cleavage induced false positive signals in most DSN signal amplification strategies have been minimised efficiently without special modifications. Importantly, the improved recognition ability of MBG3, together with the sensitive substrate selectivity of DSN, makes our novel method suitable for miRNA detection with high selectivity. The signal response of similar miRNA sequences with one-base difference has been reduced from 37% to 8% compared to the traditional linear ssDNA probe-DSN-based method.

Thioyl and sulfonyl radicals are usually produced from various thiols and sulfonyl derivatives in high efficiency by single-electron-transfer (SET) oxidation. The generated sulfur (thioyl/sulfonyl) radicals are also highly reactive intermediates having various applications in the construction of organosulfur compounds in the field of organic synthesis. Recently, photoredox-catalyzed C–S/P–S bond formation via the generation of sulfur centered radicals has been studied extensively. In the photoredox catalytic process, a variety of S–H, S–S, S–C, S–N, and S–X (F, Cl, Br, I) bonds, and even active sulfone-containing skeletons can be easily transformed into the corresponding thioyl/sulfonyl radicals. Some of these transformations are achieved by a combination of photoredox catalysts (i.e., TiO2, Bi2O3, eosin Y, fac-[Ir(ppy)3], [Ru(bpy)3]2+) and other catalysts such as strong bases, Lewis acids, organocatalysts and transition metal catalysts. Compared with previous methods, photoredox catalysis is inexpensive and features the advantages of high efficiency and easy utilization in addition to being environmentally-benign. In this review, we have focused on the research on photoredox-catalyzed C–S/P–S bond formation via the generation of thioyl/sulfonyl radicals and further functionalization in the past few years. We hope to offer chemists the tools to open the door for further progress in organsulfur chemistry.

Introduction:LHRH agonists are the mainstay for medical castration in advanced prostate cancer, however, they cause an initial testosterone (T) surge with a delayed onset of castration and require ...

As a skeleton component of plants, lignin is an organic macromolecule polymer that can be regenerated and naturally degraded. Annually, plant growth produces about 150 billion tons of lignin. In industrial processes such as paper and biomass-refining industry, large amounts of lignin are formed as by-products. Most of technical lignins are directly combusted to obtain heat, which not only is a waste of organic matter but also leads to environmental pollution and other issues. Interestingly, lignin can be used as slow-release carriers and coating materials for fertilizers due to its excellent slow release properties as well as chelating and other functionalities. Preparation of lignin-based slow/controlled release fertilizers can be achieved by sustainable chemical (ammoxidation, Mannich reaction, and other chemical modifications), coating (without or with chemical modification), and chelation modifications. This Review systematically summarizes the methods, mechanisms, and application of the above methods for preparing lignin-based slow/controlled release fertilizers. Although the evaluation standards and methods of lignin-based slow/controlled release fertilizers are not perfect, it is believed that more and more scholars will pay more attention to them to accelerate the development and application of lignin-based slow/controlled release fertilizers, so as to improve their relevant standards. In short, there is an urgent need to improve the preparation process of lignin-based slow/controlled release fertilizers and application as lignin-based slow/controlled release fertilizers to production practice as soon as possible.