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Precursor method is a well-known technology for preparing certain functional materials. In this work, a novel 3d-4f bimetallic organic framework, denoted as 45MCeCo (45 M representing 4,5-imidazole dicarboxylic acid), was successfully synthesized via a hydrothermal technique. The compound thus obtained has the molecular formula of C10H11CeCoN4O12. By meticulously controlling the amounts of the experimental materials, it was feasible to prepare flower-like crystals possessing identical single crystal structures and significantly larger specific surface areas. As a precursor for electrode materials, this structure underwent calcination at different temperatures to prepare Co3O4/CeO2 composites with in situ composite heterostructures. Post-electrochemical tests revealed that CeO2 remains unreactive across all potentials, thereby contributing to the stabilization of the electrode material structure. In contrast, Co3O4 participated in redox reactions to provide a specific capacity to the sample. In addition, when comparing the performance of the electrode material under different calcination conditions, it became evident that the material exhibited optimal electrochemical performance when subjected to a temperature of 700 °C for 2 h.

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Sudan dyes are strictly prohibited from being added to edible products as carcinogens and tetracycline hydrochloride (TC) remaining in animal-derived food may cause harm to the human body. Therefore, it is necessary to establish a high-sensitivity, simple and convenient method for the detection of Sudan dyes and TC in foods for safety purposes. In this work, multifunctional blue fluorescent carbon dots (B-CDs) were prepared by a one-step hydrothermal synthesis using glucose as the carbon source. The results show that the fluorescence intensity of B-CDs was significantly affected by the acidity of the solution and can be quenched by Sudan I, IV and TC through selective studies. Interestingly, the fluorescence quenching intensities of B-CDs have a good linear relationship with the concentration of Sudan I and IV at pH = 3-7. The wide range of pH is beneficial to broaden the application of B-CDs in a practical samples analysis. The method has been successfully applied to real food samples of tomato paste, palm oil and honey, and the detection limits are 26.3 nM, 54.2 nM and 31.1 nM for Sudan I, Sudan IV and TC, respectively. This method integrates Sudan dyes and TC into the same multifunctional B-CDs, which shows that the sensor has a great potential in food safety detection.

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Cancer is the second leading cause of death following ischemic heart disease in the world and the primary clinical, social and economic burden. Surgical resection is the main measure for the treatment of the vast majority of solid tumors. However, the recurrence and metastasis of tumors occur at different periods after surgery in many cases undergoing radical tumor surgery, which is the main cause of death of tumor patients. Moreover, tumor patients are prone to suffer from mental depression, which may increase the morbidity and mortality of tumors. Tumors have a series of clinical biological signs with the following five main features: postoperative pain and cancerous pain; suppression of antitumor immunity; angiogenesis in tumors; proliferation, growth and metastasis of tumors; and mental depression. Surgery is the first treatment in the majority of cancer patients with solid tumors. Opioids are required for anesthesia and postoperative analgesia. For cancerous pain control, patients undergo surgery, and their quality of life of is improved. However, traditional opioids, such as morphine, may inhibit antitumor immunity, induce vascular growth of tumors and promote the proliferation, invasion and migration of cancer cells, and traditional opioids can induce a risk of somatic dependence. However, studies have found that not all opioids share the effects of immunosuppression, tumor proliferation promotion and angiogenesis induction. Dezocine, a novel opioid with specific pharmacological mechanisms, has been demonstrated to regulate the five clinical and biological features of tumors. We reviewed the preclinical and clinical studies of dezocine on postoperative pain and cancer pain in tumor patients as well as the immune system, tumor angiogenesis, tumor proliferation, tumor growth, tumor metastasis and mental depression. We proposed that dezocine may be the best choice of opioids for anesthesia and analgesia in cancer patients.

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In this paper, we report a series of x polycrystalline AgCuTe1-xSe samples with high thermoelectric performance. X-ray photoelectron spectroscopy data suggest the observation of Ag+, Cu+, Te2-, and Se2- states of Ag, Cu, Te, and Se. Meanwhile, the carrier concentration of the obtained p-type samples changes from 9.12 × 1018 to 0.86 × 1018 cm-3 as their carrier mobility varies from 698.55 to 410.12 cm2·V-1·s-1 at 300 K. Compared with undoped AgCuTe, an ultralow thermal conductivity is realized in AgCuTe1-xSex due to the enhanced phonon scattering. Ultimately, a maximum figure of merit (ZT) of ∼1.45 at 573 K and a high average ZT above 1.0 at temperatures ranging from room temperature to 773 K can be achieved in AgCuTe0.9Se0.1, which increases by 186% compared to that of the undoped AgCuTe (0.82 at 573 K). This work provides a viable insight toward understanding the effect of the Se atom on the lattice structure and thermoelectric properties of AgCuTe and other transition-metal dichalcogenides.

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Light harvesting is an important part of the photocatalysis process. In this work, carbon self-doped honeycomb-like g-C3N4 with outstanding N2 photofixation ability was prepared via microwave treatment. XRD, N2 adsorption, UV-Vis, SEM, XPS, ESR and PL were used to characterize the as-prepared catalysts. Combining the carbon self-doping with microwave treatment, the n-π* transition was successfully stimulated. The remarkable red shift of absorption edge from 465 nm to near 600 nm was observed, leading to the obviously promoted visible light absorption. The synergy effect of carbon doping and microwave treatment also enhances the surface area and separation efficiency of electron-hole pairs. The as-prepared catalyst displays the highest NH4 + concentration of 5.3 mg L-1 gcat -1, over 11 times higher than that of neat g-C3N4, as well as excellent photocatalytic stability. DFT calculation was also used to further prove our point of view. This paper provides a new way for the construction of high efficiency photocatalysts.

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To date, several microorganisms that can metabolize alginate have been characterized. In these microorganisms, a class of enzymes called alginate lyases (Alys) catalyze the depolymerization of alginate into oligomers via an endolytic ß-elimination reaction. But it is not clear how these lyases differ on their enzymological functions or their divisions of labor. We focused on three extracellular secretory alginate lyases in the Gram-negative marine bacterium V.alginolyticus (ATCC 17749). We found differences in lyase function and catalytic specificity, depending on substrates. These properties apparently derived from demonstrable changes to the protein sequences. We found shared structural domains in alginate lyases specific to the pM and pG substrates through the measurements on enzyme activities and kinetic parameters. Substitution of hydrophobic amino acids in the isoleucine site of domain QIH could have an enormous influence on the high-affinity to pM or pG. This isoleucine was reconfirmed to be indispensable for recognition of the pG or G-G bond. We identified key amino acids located in the catalytic center by means of protein site-directed mutagenesis, and found specific amino acid fragments with exclusive recognitional and catalytic activity effects for different substrates. We reconstructed a series of proteins through splicing, with the goal of producing an engineered protein with the ability to degrade alginate on a variety of substrates and with high enzyme activity as well as temperature stability. Our study provides the theoretical basis for future work on alginate oligosaccharide, transport mechanisms, an area of research with potentially large ramifications for the chemical, medical, textile, printing and agricultural industries.

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BACKGROUND: Ion mobility-mass spectrometry (IMMS), an analytical technique which combines the features of ion mobility spectrometry (IMS) and mass spectrometry (MS), can rapidly separates ions on a millisecond time-scale. IMMS becomes a powerful tool to analyzing complex mixtures, especially for the analysis of peptides in proteomics. The high-throughput nature of this technique provides a challenge for the identification of peptides in complex biological samples. As an important parameter, peptide drift time can be used for enhancing downstream data analysis in IMMS-based proteomics. RESULTS: In this paper, a model is presented based on least square support vectors regression (LS-SVR) method to predict peptide ion drift time in IMMS from the sequence-based features of peptide. Four descriptors were extracted from peptide sequence to represent peptide ions by a 34-component vector. The parameters of LS-SVR were selected by a grid searching strategy, and a 10-fold cross-validation approach was employed for the model training and testing. Our proposed method was tested on three datasets with different charge states. The high prediction performance achieve demonstrate the effectiveness and efficiency of the prediction model. CONCLUSIONS: Our proposed LS-SVR model can predict peptide drift time from sequence information in relative high prediction accuracy by a test on a dataset of 595 peptides. This work can enhance the confidence of protein identification by combining with current protein searching techniques.

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OBJECTIVE: To establish pharmacognostical methods of Rodersia aesculifolia. METHODS: Macroscopical, microscopic and physicochemical identification were used to authenticate this crude drug, and the identification characteristics were studied. RESULTS: There were some palea on the rhizoma superior extremity and some white flare dot on transverse section. Vascular bundle formed into interval circularity in rhizoma transverse section, and some small atypia bundle appeared in lateral of core. Xylem of root was tetrarch. A lot of starch grain and acicular cyrstal were observed in parenchyma cell. Brown cell was present as single or several linked. CONCLUSION: These characteristics can be used as identification basis for Rodersia aesulifolia Batal.

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