The bis(imino)pyridine iron complex, for the first time, is developed as an effective metal carbene catalyst for carbene transfer reactions of donor-acceptor diazo compounds. Its broad catalytic ...capability is demonstrated by a range of metal carbene reactions, from cyclopropanation, cyclopropenation, epoxidation, and Doyle-Kirmse reaction to O-H insertion, N-H insertion, and C-H insertion reactions. The asymmetric cyclopropanation of styrene and methyl phenyldiazoacetate was successfully achieved by the new chiral bis(imino)pyridine iron catalyst, which delivers a new gateway for the development of chiral iron catalysis for metal carbene reactions.
The bis(imino)pyridine iron complex, for the first time, is developed as an effective metal carbene catalyst for carbene transfer reactions of donor-acceptor diazo compounds.
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IJS, KILJ, NUK, UL, UM, UPUK
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•A novel optosensor was developed based on UCNPs decorated with different metal ions.•The sensor displayed a high selectivity and high sensitivity for catecholamines (CAs), dopamine, ...and epinephrine.•It gave an excellent analytical performance with low LODs and reproducibility.•It was employed for sensing CAs in biological fluids with satisfactory recoveries.
We developed a novel optical sensor for sensitive and selective detection of catecholamines based on upconversion nanoparticles (UCNPs) decorated with different metal ions (UCNP-Men+). 1,2-ethanedithiol was chosen as a surface additive to synthesize the NaLuGdF4:Yb3+/Er3+ UCNPs by one-step at 200 °C. The as-prepared UCNPs exhibited a strong emission under the continuous excitation at 980 nm. It was found that catecholamines could be more effectively detected in the presence of UCNP-Fe3+, whereas, dopamine and epinephrine were detected selectively using UCNP-Li+ and UCNP-Cu2+ sensors, respectively. Under the optimum conditions, the limit of detections (LODs) for catecholamines, dopamine, and epinephrine are 2.8, 2.5, and 2.4 nM, respectively, with good linearity in the range of 5–320 nM for total catecholamines and 5–30 nM for dopamine and epinephrine. The developed method has been successfully applied to detect dopamine and epinephrine in human urine samples with good accuracy and satisfactory recovery.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A
bstract
Studies of dark matter lie at the interface of collider physics, astrophysics and cosmology. Constraining models featuring dark matter candidates entails the capability to provide accurate ...predictions for large sets of observables and compare them to a wide spectrum of data. We present a framework which, starting from a model Lagrangian, allows one to consistently and systematically make predictions, as well as to confront those predictions with a multitude of experimental results. As an application, we consider a class of simplified dark matter models where a scalar mediator couples only to the top quark and a fermionic dark sector (i.e. the simplified top-philic dark matter model). We study in detail the complementarity of relic density, direct/indirect detection and collider searches in constraining the multi-dimensional model parameter space, and efficiently identify regions where individual approaches to dark matter detection provide the most stringent bounds. In the context of collider studies of dark matter, we point out the complementarity of LHC searches in probing different regions of the model parameter space with final states involving top quarks, photons, jets and/or missing energy. Our study of dark matter production at the LHC goes beyond the tree-level approximation and we show examples of how higher-order corrections to dark matter production processes can affect the interpretation of the experimental results.
Iron cobalt oxides, such as typical FeCo2O4 and CoFe2O4, are two spinel structured transitional metal oxide materials with excellent electrochemical performance. As the electrodes, they have been ...widely applied in the current energy storage and conversion processes such as supercapacitors, Lithium-ion batteries and fuel cells. Based on synthesis approaches and controlled conditions, these two materials exhibited broad morphologies and nanostructures and thus distinct electrochemical performance. Some of them have shown promising applications as electrodes in energy storage and conversion. The incorporation with other materials to form composites further improved their performance. This review briefly summarized the recent applications of FeCo2O4 and CoFe2O4 in energy storage and conversion, current understandings on mechanisms and especially the relevance of morphologies and structures and composites to electrochemical performance. Some recommendations were finally put forward addressing current issues and future prospects on electrodes of FeCo2O4 and CoFe2O4 based materials in energy storage and conversion, implying there was still space to further optimize their performance.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The impact of anaerobic digestion of animal waste on the persistence of antibiotic resistance genes (ARGs) and antibiotics is not widely studied. Two identical, 800‐L digesters seeded with swine ...slurry were followed up to 100 d in three separate trials. The trials received varying amounts of antibiotic‐free corn (Zea mays L.) mixed with water to maintain the digestion process. Biogas production, seven tetracycline resistance (tet) genes, and three tetracyclines and their transformation products were measured. Biogas production proportionally increased as the feeding loads increased between trials. In Trial 1, log10 tet gene copies showed small but statistically significant (P < 0.01) increases during digestion. In Trial 2, anaerobic digestion did not have a significant (P > 0.05) effect except for significant reductions in tetB (P < 0.0001) and tetG (P = 0.0335) log10 gene copies. In Trial 3, which received the highest amount of corn mix, log10 copies of the 16S ribosomal RNA and the tet genes significantly (P < 0.0001) reduced over time during digestion. Up to 36 μg L−1 tetracycline, 112 μg L−1 chlortetracycline, 11.9 mg L−1 isochlortetracycline, and 30 μg L−1 4‐epitetracycline were detected both in the liquid and solid digestates. Results of this study revealed that although anaerobic digestion of swine waste can produce useful biogas, it does not result in complete removal of bacteria, ARGs, and antibiotics regardless of differences in the feeding loads between trials. Further effluent and sludge treatments are required prior to their downstream use in crop production to minimize emergence and environmental dissemination of antimicrobial‐resistant bacteria through animal manure.
Core Ideas
Anaerobic digestion did not completely remove resistance genes from swine waste.
Tetracycline antibiotics were detected from 30 μg L−1 to 11.9 mg L−1.
Further waste treatments are required to reduce the spread of resistance genes.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
We investigated the anaerobic degradation of tetracycline antibiotics (tetracycline TC, oxytetracycline OTC and chlortetracycline CTC) in swine, cattle, and poultry manures. The manures were ...anaerobically digested inside polyvinyl chloride batch reactors for 64 days at room temperature. The degradation rate constants and half-lives of the parent tetracyclines were determined following first-order kinetics. For CTC the fastest degradation rate was observed in swine manure (k = 0.016 ± 0.001 d
−1
; half-life = 42.8 days), while the slowest degradation rate was observed in poultry litter (k = 0.0043 ± 0.001 d
−1
; half-life = 161 days). The half-lives of OTC ranged between 88.9 (cattle manure) and 99.0 days (poultry litter), while TC persisted the longest of the tetracycline antibiotics studied with half-lives ranging from 92.4 days (cattle manure) to 330 days (swine manure). In general, the tetracyclines were found to degrade faster in cattle manure, which had the lowest concentrations of organic matter and metals as compared to swine and poultry manures. Our results demonstrate that tetracycline antibiotics persist in the animal manure after anaerobic digestion, which can potentially lead to emergence and persistence of antibiotic resistant bacteria in the environment when anaerobic digestion byproducts are land applied for crop production.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Increased demand for animal protein is met by increased food animal production resulting in large quantities of manure. Animal producers, therefore, need sustainable agricultural practices to protect ...environmental health. Large quantities of antimicrobials are used in commercial food animal production. Consequently, antimicrobial-resistant bacteria and the resistance genes emerge and are excreted through feces. Manure management is essential for the safe disposal of animal waste. Lagoons, with or without covers, and anaerobic digesters, with the primary purpose of methane production, and composting, with the primary purpose of producing organic fertilizer, are widely used methods of manure treatment. We reviewed manure management practices and their impact on tetracycline resistance genes. Lagoons are maintained at ambient temperatures; especially uncovered lagoons are the least effective in removing tetracycline resistance genes. However, some modifications can improve the performance of lagoons: sequential use of uncovered lagoons and the use of covered lagoons resulted in a one-log reduction, while post-treatments such as biofiltration following covered lagoon treatment resulted in 3.4 log reduction. Mesophilic digestion of animal manure did not have any significant effect; only a 0.7 log reduction in tet(A) was observed in one study. While thermophilic anaerobic digesters are effective, if properly operated, they are expensive for animal producers. Aerobic thermophilic composting is a promising technology if optimized with its economic benefits. Composting of raw animal manure can result in up to a 2.5 log reduction, and postdigestion composting can reduce tetracycline resistance gene concentration by >80%. In general, manure management was not designed to mitigate antimicrobial resistance; future research is needed to optimize the economic benefits of biogas or organic fertilizer on the one hand and for the mitigation of foodborne pathogens and antimicrobial resistance on the other.
We discuss the phenomenology associated with a resonant monotop collider signal, i.e. a signal in which a single top quark is resonantly produced in association with missing energy through an
s
...-channel scalar exchange. We study both the bounds originating from dedicated monotop searches performed by the ATLAS and CMS experiments, and the constraints associated with other processes that could be induced by a new physics context favouring monotop production at colliders. The latter class of constraints includes, in particular, the recasting of analyses from the LHC and the TeVatron. All theoretical calculations are performed at the next-to-leading order accuracy in QCD, and we finally combine all results to establish the present limits on the parameter space and test the relevance of the monotop signal at the LHC Run 2.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Traditional Polynesian medicine for children has been poorly documented, and few data are available on their efficacy and safety. In this context, the aim of this study was to identify traditional ...practices used for treating children and then assess the efficacy and safety of the most cited remedies by reviewing the literature. In 2022, a semi-structured survey was carried out on five islands from the Society archipelago (Bora Bora, Huahine, Moorea, Raiatea, and Tahiti). A total of 86 participants were interviewed including 19 experts in herbalism. A thorough literature review was performed on the most cited plant species to gather the relevant ethnobotanical, pharmacological, and clinical data of each remedy. Our survey confirms the importance of traditional medical practices for children in the Society Islands. A lack of data in children for most cited remedies demonstrate the need for more pharmacological and toxicological research on Polynesian medicinal plants. Finally, the potential risk of toxicity for some cited plant species reported calls for a better information of traditional medicine users and healers.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK