Ambient electric arc ionization for versatile sample analysis using mass spectrometry.

A novel, convenient ambient electric arc ionization (AEAI) device was developed as a mass spectrometry ion source for versatile sample analysis. AEAI could be considered as a soft ionization technique in which the protonated ion ([M + H]+) is the main ion species with little or no in-source fragmentation for most analytes. Coupled with a high-resolution Orbitrap mass spectrometer, AEAI could be applied to the analysis of a variety of organic compounds having a wide range of polarities, ranging from non-polar species such as polybenzenoid aromatic hydrocarbons (PAHs) to highly polar species such as amino acids. With its versatile capabilities in the mass spectrometric analysis of small molecules, AEAI has the potential to be an alternative to traditional ionization methods such as electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI), and electron impact (EI) ionization. The limitations of AEAI are also discussed.

Design, synthesis, and evaluation of novel coumarin-dithiocarbamate derivatives (IDs) as anti-colorectal cancer agents.

Colorectal cancer (CRC) is a common malignant tumour of human digestive tract. The high mortality rate of CRC is closely related to the limitations of existing treatments. Thus, there is an urgent need to search for new anti-CRC agents. In this work, twenty novel coumarin-dithiocarbamate derivatives (IDs) were designed, synthesized and evaluated in vitro. The results suggest that the most active compound ID-11 effectively inhibited the proliferation of CRC cell lines while shown little impact on normal colon epithelial cells. Mechanism studies revealed that ID-11 displayed bromodomain-containing protein 4 inhibitory activity, and induced G2/M phase arrest, apoptosis as well as decreased the expression levels of the key genes such as c-Myc and Bcl-2 in CRC cell lines. Moreover, the ADMET properties prediction results shown that ID-11 possess well metabolic characteristics without obvious toxicities. Our data demonstrated that compound ID-11 may be a promising anti-CRC agent and deserved for further development.

Synthesis of unsymmetrical disulfides via PPh3-mediated reductive coupling of thiophenols with sulfonyl chlorides.

A facile and rapid synthesis of unsymmetrical aryl disulfides using PPh3-mediated reductive coupling of thiophenols with aryl sulfonyl chlorides was described. Good functional group tolerance and scalability were achieved in this strategy. More importantly, the approach enables the introduction of sulfonyl chlorides into the synthesis of asymmetric organic disulfides under catalyst- and base-free conditions. Using this method, unsymmetrical aromatic disulfides could be prepared from inexpensive and readily available starting materials in moderate to excellent isolated yields, through a nucleophilic substitution pathway.

Evaluation of the Intelligent Sprayer System in Peach Production.

Air-blast sprayers are routinely used to apply pesticides in commercial peach orchards, with growers using both conventional air-blast and ultrasonic sensor-driven models. Even with advanced spray technologies, there are still concerns with the amount of chemicals used and lost to drift. Our study evaluated a laser sensor-based variable-rate sprayer system in three experimental peach orchards for pest and brown rot disease control, spray volume output, spray coverage, and spray drift. A single 378-liter air-blast sprayer was used for both the conventional air-blast and the Intelligent Sprayer (iSprayer) treatments. Treatments were started at the phenological stage of bloom and continued through final swell. The iSprayer treatment was as effective in controlling pests and brown rot disease as the conventional air-blast treatment. Compared with the conventional air-blast treatment, the iSprayer treatment reduced the spray volume (liters/hectare) in cultivar PF23 by 71% at bloom, 62% at pit hardening, and 55% at final swell. For Juneprince, the spray volume reduction was 50% at bloom, 40% at pit hardening, and 13% at final swell. Spray drift was significantly (P < 0.05) reduced only at bloom in the iSprayer treatment. Spray coverage was increased by 50.13 and 26.67% in the iSprayer treatment at bloom and pit hardening, respectively, but not at final swell. Our results show that the iSprayer maintained pest and disease control efficacy in peach orchards while reducing spray volume and drift compared with the conventional air-blast treatment.

Aerobic Copper-Catalyzed Synthesis of (E)-Vinyl Sulfones by Direct C-S Bond Oxidative Coupling.

Copper-catalyzed aerobic oxidative C-S bond coupling reaction between thiophenols and aryl-substituted alkenes for (E)-vinyl sulfones synthesis is reported here. With air utilized as a green oxidant, this transformation not only produces various vinyl sulfones in moderate to good yields but also possesses a simple and ecofriendly system. To clarify the mechanism, kinetic experiments has been investigated.

Development of Fast E-nose System for Early-Stage Diagnosis of Aphid-Stressed Tomato Plants.

An electronic nose (E-nose) system equipped with a sensitive sensor array was developed for fast diagnosis of aphid infestation on greenhouse tomato plants at early stages. Volatile organic compounds (VOCs) emitted by tomato plants with and without aphid attacks were detected using both the developed E-nose system and gas chromatography mass spectrometry (GC-MS), respectively. Sensor performance, with fast sensor responses and high sensitivity, were observed using the E-nose system. A principle component analysis (PCA) indicated accurate diagnosis of aphid-stressed plants compared to healthy ones, with the first two PCs accounting for 86.7% of the classification. The changes in VOCs profiles of the healthy and infested tomato plants were quantitatively determined by GC-MS. Results indicated that a group of new VOCs biomarkers (linalool, carveol, and nonane (2,2,4,4,6,8,8-heptamethyl-)) played a role in providing information on the infestation on the tomato plants. More importantly, the variation in the concentration of sesquiterpene VOCs (e.g., caryophyllene) and new terpene alcohol compounds was closely associated with the sensor responses during E-nose testing, which verified the reliability and accuracy of the developed E-nose system. Tomato plants growing in spring had similar VOCs profiles as those of winter plants, except several terpenes released from spring plants that had a slightly higher intensity.

Associations between ERα/ß gene polymorphisms and osteoporosis susceptibility and bone mineral density in postmenopausal women: a systematic review and meta-analysis.

BACKGROUND: Many studies have reported associations between estrogen receptor (ER) gene polymorphisms and postmenopausal osteoporosis (PMOP) risk and bone mineral density (BMD), but the results are controversial. The aim of the present meta-analysis is to verify the association between ERα and ERß gene polymorphisms and osteoporosis susceptibility and BMD in postmenopausal women. METHODS: PubMed, EMBASE, Web of Science, the Cochrane Library and China WeiPu Library were searched. OR and WMD with 95% CI were calculated to assess the association. RESULTS: Overall, no significant association was observed between ERα XbaI, ERα PvuII and PMOP susceptibility in either overall, Caucasian or Asian populations. ERα G2014A was significantly associated with a decreased risk of PMOP in Caucasian populations. There was a significant association between ERß RsaI and PMOP risk in both overall and Asian populations. Caucasian PMOP women with ERα XbaI XX and Xx genotypes had a higher LS Z value than women with xx genotype. ERα XbaI XX genotype was associated with increased FN BMD in overall and Caucasian populations, an increased FN Z value in Asians, and a decreased FN Z value in Caucasians. There was also a significant association between ERα XbaI Xx genotype and an increased FN Z value in either Asians or Caucasians. ERα PvuII PP genotype was associated with a low LS Z value in Caucasians and a low FN BMD and Z value in Asians. Pp genotype in PMOP women was significantly correlated with low LS BMD in overall populations, a low FN Z value in either overall, Caucasian or Asian populations. CONCLUSION: Each ERα and ERß gene polymorphism might have different impact on PMOP risk and BMD in various ethnicities.

Plant Pest Detection Using an Artificial Nose System: A Review.

This paper reviews artificial intelligent noses (or electronic noses) as a fast and noninvasive approach for the diagnosis of insects and diseases that attack vegetables and fruit trees. The particular focus is on bacterial, fungal, and viral infections, and insect damage. Volatile organic compounds (VOCs) emitted from plants, which provide functional information about the plant's growth, defense, and health status, allow for the possibility of using noninvasive detection to monitor plants status. Electronic noses are comprised of a sensor array, signal conditioning circuit, and pattern recognition algorithms. Compared with traditional gas chromatography-mass spectrometry (GC-MS) techniques, electronic noses are noninvasive and can be a rapid, cost-effective option for several applications. However, using electronic noses for plant pest diagnosis is still in its early stages, and there are challenges regarding sensor performance, sampling and detection in open areas, and scaling up measurements. This review paper introduces each element of electronic nose systems, especially commonly used sensors and pattern recognition methods, along with their advantages and limitations. It includes a comprehensive comparison and summary of applications, possible challenges, and potential improvements of electronic nose systems for different plant pest diagnoses.

Evaluation of Object Surface Edge Profiles Detected with a 2-D Laser Scanning Sensor.

Canopy edge profile detection is a critical component of plant recognition in variable-rate spray control systems. The accuracy of a high-speed 270° radial laser sensor was evaluated in detecting the surface edge profiles of six complex-shaped objects. These objects were toy balls with a pink smooth surface, light brown rectangular cardboard boxes, black and red texture surfaced basketballs, white smooth cylinders, and two different sized artificial plants. Evaluations included reconstructed three-dimensional (3-D) images for the object surfaces with the data acquired from the laser sensor at four different detection heights (0.25, 0.50, 0.75, and 1.00 m) above each object, five sensor travel speeds (1.6, 2.4, 3.2, 4.0, and 4.8 km h-1), and 8 to 15 horizontal distances to the sensor ranging from 0 to 3.5 m. Edge profiles of the six objects detected with the laser sensor were compared with images taken with a digital camera. The edge similarity score (ESS) was significantly affected by the horizontal distances of the objects, and the influence became weaker when the objects were placed closer to each other. The detection heights and travel speeds also influenced the ESS slightly. The overall average ESS ranged from 0.38 to 0.95 for all the objects under all the test conditions, thereby providing baseline information for the integration of the laser sensor into future development of greenhouse variable-rate spray systems to improve pesticide, irrigation, and nutrition application efficiencies through watering booms.

Synthesis and biological evaluation of allylated mono-carbonyl analogues of curcumin (MACs) as anti-cancer agents for cholangiocarcinoma.

A series of new allylated mono-carbonyl curcumin analogues (MACs) were designed and synthesized. In vitro cytotoxic activities of allylated MACs 6a-h together with previously reported analogues 4a-i and 7a-e, were tested against human cholangiocarcinoma cell lines including HUCCA, QBC-939 and RBE. Of all the compounds tested, 6c exhibited potent in vitro antiproliferative activity against the three tested cancer cell lines with IC50 values of 8.7, 9.3 and 8.9µM, respectively. Cell cycle analysis showed that 6c inhibited cell proliferation due to G2/M arrest. Furthermore, mechanistic studies revealed that 6c dose-dependently increased the level of Bax and inhibited the expression of Bcl-2, to induce cancer cell apoptosis. Taken together, this work provides a novel series of anti-cancer candidates for the treatment of cholangiocarcinoma.

Development of Sustainable and Active Food Packaging Materials Composed by Chitosan, Polyvinyl Alcohol and Quercetin Functionalized Layered Clay.

In order to solve the problems of insufficient active functions (antibacterial and antioxidant activities) and the poor degradability of traditional plastic packaging materials, biodegradable chitosan (CS)/polyvinyl alcohol (PVA) nanocomposite active films reinforced with natural plant polyphenol-quercetin functionalized layered clay nanosheets (QUE-LDHs) were prepared by a solution casting method. In this study, QUE-LDHs realizes a combination of the active functions of QUE and the enhancement effect of LDHs nanosheets through the deposition and complexation of QUE and copper ions on the LDHs. Infrared and thermal analysis results revealed that there was a strong interface interaction between QUE-LDHs and CS/PVA matrix, resulting in the limited movement of PVA molecules and the increase in glass transition temperature and melting temperature. With the addition of QUE-LDHs, the active films showed excellent UV barrier, antibacterial, antioxidant properties and tensile strength, and still had certain transparency in the range of visible light. As QUE-LDHs content was 3 wt%, the active films exhibited a maximum tensile strength of 58.9 MPa, representing a significant increase of 40.9% compared with CS/PVA matrix. Notably, the UV barrier (280 nm), antibacterial (E. coli) and antioxidant activities (DPPH method) of the active films achieved 100.0%, 95.5% and 58.9%, respectively. Therefore, CS/PVA matrix reinforced with QUE-LDHs has good potential to act as an environmentally and friendly active packaging film or coating.

A covalent compound selectively inhibits RNA demethylase ALKBH5 rather than FTO.

N 6-Methyladenosine (m6A) is the most prevalent mRNA modification and is required for gene regulation in eukaryotes. ALKBH5, an m6A demethylase, is a promising target, particularly for anticancer drug discovery. However, the development of selective and potent inhibitors of ALKBH5 rather than FTO remains challenging. Herein, we used a targeted covalent inhibition strategy and identified a covalent inhibitor, TD19, which selectively inhibits ALKBH5 compared with FTO demethylase in protein-based and tumor cell-based assays. TD19 irreversibly modifies the residues C100 and C267, preventing ALKBH5 from binding to m6A-containing RNA. Moreover, TD19 displays good anticancer efficacy in acute myeloid leukemia and glioblastoma multiforme cell lines. Thus, the ALKBH5 inhibitor developed in this study, which selectively targets ALKBH5 compared with FTO, can potentially be used as a probe for investigating the biological functions of RNA demethylase and as a lead compound in anticancer research.

(E)-3-(3,4-Di-fluoro-phen-yl)-1-(3,4-di-meth-oxy-phen-yl)prop-2-en-1-one.

In the title compound, C17H14F2O3, the dihedral angle between the benzene rings is 20.56 (8)° and the H atoms at the central propenone group are trans configured. One of the F atoms is disordered over two positions (occupancy ratio 0.57:0.43) and was refined using a split model. In the crystal, the molecules are linked into centrosymmetrical dimers and are further connected into a three-dimensional network via weak C-H⋯O interactions.

The Key to Solving Plastic Packaging Wastes: Design for Recycling and Recycling Technology.

Confronted with serious environmental problems caused by the growing mountains of plastic packaging waste, the prevention and control of plastic waste has become a major concern for most countries. In addition to the recycling of plastic wastes, design for recycling can effectively prevent plastic packaging from turning into solid waste at the source. The reasons are that the design for recycling can extend the life cycle of plastic packaging and increase the recycling values of plastic waste; moreover, recycling technologies are helpful for improving the properties of recycled plastics and expanding the application market for recycled materials. This review systematically discussed the present theory, practice, strategies, and methods of design for recycling plastic packaging and extracted valuable advanced design ideas and successful cases. Furthermore, the development status of automatic sorting methods, mechanical recycling of individual and mixed plastic waste, as well as chemical recycling of thermoplastic and thermosetting plastic waste, were comprehensively summarized. The combination of the front-end design for recycling and the back-end recycling technologies can accelerate the transformation of the plastic packaging industry from an unsustainable model to an economic cycle model and then achieve the unity of economic, ecological, and social benefits.

Golgi-protein 73 facilitates vimentin polymerization in hepatocellular carcinoma.

Golgi-protein 73 (GP73) is highly expressed in hepatocellular carcinoma (HCC) and, as a secretory protein, it has been proposed as a serum biomarker indicating progression of HCC. The underlying mechanism by which GP73 may promote HCC metastasis is still poorly understood. In this study, we discovered that GP73 interacted with vimentin to facilitate Serine/Threonine-protein phosphatase PP1-alpha (PP1A)-mediated dephosphorylation of vimentin at S56 and facilitated vimentin polymerization, which blocked vimentin degradation via TRIM56-mediated ubiquitin/proteasome-dependent pathway. Strikingly, Clomipramine, a 5-hydroxytryptamine receptor (5-HTR) agonist approved for the treatment of depression, impaired GP73-mediated vimentin polymerization to effectively inhibit metastasis of HCC with high GP73 expression, which provided a new strategy against HCC metastasis. Lastly, it was found that serum GP73 (sGP73) correlated positively with vimentin in primary tissues of HCC, suggesting that sGP73 might serve as a potential serum biomarker for companion diagnosis of HCC with highly expressed vimentin. In summary, this study reveals the process of GP73-mediated vimentin polymerization and proves that Clomipramine serves as a potential drug targeting vimentin for metastatic HCC patients with high sGP73 level.

Design, synthesis, and biological evaluation of novel spirocyclic compounds as potential anti-glioblastoma agents.

Glioblastoma (GBM) is an aggressive brain tumor with extremely limited clinical treatment options. Because of the blood-brain barrier (BBB), it is difficult for anti-GBM drug candidates to enter the brain to exert their therapeutic effects. The spirocyclic skeleton structure exhibits good lipophilicity and permeability, enabling small-molecule compounds to cross the BBB. Herein, we designed and synthesized novel 3-oxetanone-derived spirocyclic compounds containing a spiro[3.4]octane ring and determined their structure-activity relationship for antiproliferation in GBM cells. Among these, the chalcone-spirocycle hybrid 10m/ZS44 exhibited high antiproliferative activity in U251 cells and permeability in vitro. Furthermore, 10m/ZS44 activated the SIRT1/p53-mediated apoptosis pathway to inhibit proliferation in U251 cells, whereas it minimally impaired other cell-death pathways, such as pyroptosis or necroptosis. In a mouse xenograft model, 10m/ZS44 exhibited a substantial inhibitory effect on GBM tumor growth without showing obvious toxicity. Overall, 10m/ZS44 represents a promising spirocyclic compound for the treatment of GBM.

Effects of electrode materials and dimensions of an electrostatic spray scrubber on water droplet charging for dust removal.

Droplet charging is an effective method to enhance dust removal efficiency using an electrostatic spray scrubber (ESS). However, effects of the materials and dimensions of different electrodes on droplet charging efficiency have not been studied systematically. In this study, ring-shaped electrodes were selected to test effects of three types of electrode materials (copper, stainless steel, and graphite) with various dimensions on droplet charging efficiency. A Faraday pail charge measurement device was used to measure the droplet charge generated by the electrodes. A reduced factorial design with four factors was used in this study to investigate the charging efficiency affected by the factors. The four factors tested were electrode material, electrode diameter, nozzle height, and applied voltage. A 304L stainless steel electrode was found to achieve higher droplet charge-to-mass ratio (CMR) values than identically shaped electrodes made from either copper or graphite. The optimal stainless steel electrode inner diameter was 100 mm. The 304L stainless-steel electrode with this optimal diameter and a height of 45 mm achieved the highest mean CMR of 0.435 ± 0.002 mC kg-1 at an applied voltage of -11 kV with the bottom of the nozzle tip positioned 15 mm below the top of the electrode.Implications Currently, the low removal efficiency of submicron particles cannot meet the environmental control requirements of industrial applications that may have significant concentrations of particulate matter (PM) in this size range. As stricter environmental regulations are increasingly enforced, there is an urgent need to efficiently remove submicron dust particles from the air. Experiments show that the dust capture process is improved by charging droplets in the spray separator and reducing the secondary escape of dust particles in the electrostatic precipitatorAlthough high-voltage charging of droplets has been investigated in many studies, the effect of electrode material and size on droplet CMR is still not fully understood. The purpose of this study was to (1) quantify the performance of 304L stainless steel (304L SS), copper, and high-purity graphite electrodes for spray droplet CMR, (2) evaluate effects of the applied voltage, nozzle height, electrode material and dimension on CMR, and (3) optimize the specific values of key design factors and operating parameters that lead to the highest CMR. The results of this study aim to optimize electrostatic spray scrubbers to achieve high droplet CMR values.

An Electrochemical Way to Generate Amphiphiles from Hydrazones for the Synthesis of 1,2,4-Triazole Scaffold Cyclic Compounds.

An electro-oxidative cyclization pathway in which hydrazones are selected as starting materials to generate amphiphiles by reacting with benzylamines and benzamides was reported. This strategy successfully prepared a series of 1,2,4-triazoles in satisfactory yields. Moreover, the use of cheap stainless steel as the anode, the feasibility to conduct the transformation as a one-pot reaction and the proof that scaling-up these reactions is possible make this transformation attractive for potential application in industry.

Robust crop and weed segmentation under uncontrolled outdoor illumination.

An image processing algorithm for detecting individual weeds was developed and evaluated. Weed detection processes included were normalized excessive green conversion, statistical threshold value estimation, adaptive image segmentation, median filter, morphological feature calculation and Artificial Neural Network (ANN). The developed algorithm was validated for its ability to identify and detect weeds and crop plants under uncontrolled outdoor illuminations. A machine vision implementing field robot captured field images under outdoor illuminations and the image processing algorithm automatically processed them without manual adjustment. The errors of the algorithm, when processing 666 field images, ranged from 2.1 to 2.9%. The ANN correctly detected 72.6% of crop plants from the identified plants, and considered the rest as weeds. However, the ANN identification rates for crop plants were improved up to 95.1% by addressing the error sources in the algorithm. The developed weed detection and image processing algorithm provides a novel method to identify plants against soil background under the uncontrolled outdoor illuminations, and to differentiate weeds from crop plants. Thus, the proposed new machine vision and processing algorithm may be useful for outdoor applications including plant specific direct applications (PSDA).

Improved mechanical, antibacterial and UV barrier properties of catechol-functionalized chitosan/polyvinyl alcohol biodegradable composites for active food packaging.

Bioinspired from adhesion behaviors of mussels, we first reported a new strategy to prepare catechol-functionalized chitosan (C-CS)/polyvinyl alcohol (PVA) composite films via a solution blending method in neutral aqueous solution for active food packaging. Compared with pure PVA film, the UV transmittance (at 280 nm) of C-CS/PVA composite films decreases by 67.6 % when C-CS content reaches 10 wt%. Still, all the C-CS/PVA composite films are transparent in the visible range. The maximal tensile strength and elongation at break of C-CS/PVA composite films can reach 45.2 MPa and 153 % respectively, which are 46.3 % and 25.4 % higher than those of pure PVA film. The incorporation of C-CS into PVA matrix increases the antibacterial properties significantly. The water resistance of C-CS/PVA composite films can not be significantly deteriorated by the appropriate amount of C-CS. Therefore, C-CS/PVA composite films show great potential in the field of active packaging due to its good mechanical, antibacterial and UV barrier properties.