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Adults with atherosclerotic cardiovascular disease (ASCVD) are recommended high-intensity statins, with those at very high risk for recurrent events recommended adding ezetimibe and/or a proprotein convertase subtilisin/kexin type 9 inhibitor if their low-density lipoprotein cholesterol (LDL-C) is ≥70 mg/dL. We estimated the number of recurrent ASCVD events potentially averted if all adults in the United States (US) ≥45 years of age with ASCVD achieved an LDL-C

This study focused on the volatile organic compounds (VOCs) abatement by catalytic combustion/adsorption over Rh-based/ZSM-5. A series of Rh-based catalysts were prepared by wet co-impregnation method and evaluated by toluene combustion. Rh1Cu3/ZSM-5 presented superb toluene catalytic activity, great long-run stability, and excellent catalytic adaptability to various VOCs. Besides, Rh1Cu3/ZSM-5 performed good toluene adsorption capability in the column breakthrough experiments. Characterization results indicated that the interaction between Rh species and Cu oxides increased the content of chemisorbed oxygen in lattice layer (Oads-chem), which improved the catalytic performance efficiently. Moreover, Rh1Cu3/ZSM-5 showed excellent adsorption ability for toluene due to its large specific surface area, and the strong interaction between metal nanoparticles and VOCs molecules. Overall, this kind of bifunctional materials with dual-metal modification were significant for the development of VOCs abatement.

Background The global pork industry is continuously affected by infectious diseases that can result in large-scale mortality, trade restrictions, and major reductions in production. Nevertheless, the cause of many infectious diseases in pigs remains unclear, largely because commonly used diagnostic tools fail to capture the full diversity of potential pathogens and because pathogen co-infection is common. Results We used a meta-transcriptomic approach to systematically characterize the pathogens in 136 clinical cases representing different disease syndromes in pigs, as well as in 12 non-diseased controls. This enabled us to simultaneously determine the diversity, abundance, genomic information, and detailed epidemiological history of a wide range of potential pathogens. We identified 34 species of RNA viruses, nine species of DNA viruses, seven species of bacteria, and three species of fungi, including two novel divergent members of the genus Pneumocystis. While most of these pathogens were only apparent in diseased animals or were at higher abundance in diseased animals than in healthy animals, others were present in healthy controls, suggesting opportunistic infections. Importantly, most of the cases examined here were characterized by co-infection with more than two species of viral, bacterial, or fungal pathogens, some with highly correlated occurrence and abundance levels. Examination of clinical signs and necropsy results in the context of relevant pathogens revealed that a multiple-pathogen model was better associated with the data than a single-pathogen model was. Conclusions Our data demonstrate that most of the pig diseases examined were better explained by the presence of multiple rather than single pathogens and that infection with one pathogen can facilitate infection or increase the prevalence/abundance of another. Consequently, it is generally preferable to consider the cause of a disease based on a panel of co-infecting pathogens rather than on individual infectious agents.

Covalent organic frameworks have attracted great attention due to their extensive applications in energy storage, gas separation, catalysis, and photoelectric devices over the past decades. However, the design and synthesis of COFs with fluorescent units have been considered as a big challenge. Herein, we report a porphyrin-based covalent organic framework (TPE-Por-4) by the condensation of the C4-symmetric and D2h-symmetric monomers. Through a series of characterizations, its structure was confirmed. It was found that TPE-Por-4 shows unique fluorescent properties originated from both of porphyrin and tetraphenylethylene building blocks, its suspensions emit strong fluorescence and display an apparent response to pH fluctuation ranging from 2 to 4, and thus, a promising method was provided for spectroscopic monitoring of medium pH value.

Glucose and fatty acids are the major sources of energy for human body. Cholesterol, the most abundant sterol in mammals, is a key component of cell membranes although it does not generate ATP. The metabolisms of glucose, fatty acids and cholesterol are often intertwined and regulated. For example, glucose can be converted to fatty acids and cholesterol through de novo lipid biosynthesis pathways. Excessive lipids are secreted in lipoproteins or stored in lipid droplets. The metabolites of glucose and lipids are dynamically transported intercellularly and intracellularly, and then converted to other molecules in specific compartments. The disorders of glucose and lipid metabolism result in severe diseases including cardiovascular disease, diabetes and fatty liver. This review summarizes the major metabolic aspects of glucose and lipid, and their regulations in the context of physiology and diseases.

Functionalization of covalent organic frameworks (COFs) with specific groups will endow them special characteristics, and further complexation with transition metals may improve their catalytic performance and widen their applications. Herein, we constructed an amino-functionalized covalent organic framework TpPa–NH2 by the facile reduction in TpPa–NO2 and took it as a carrier for transition metal ion Cu(II) to yield a hybrid Cu–COF. All characterizations verified that the crystallinity and porosity of original COF were retained after functionalization. Subsequent evaluation of their catalytic performance indicated that the framework TpPa–NH2 has potential application in alkali-catalyzed reactions, while the hybrid Cu–COF displayed satisfactory catalytic performance both in selective oxidation of styrene and the reduction in 4-nitrophenol to 4-aminophenol. The above results demonstrated that TpPa–NH2 is a promising platform with diverse applications, and the introduction of Cu(II) will endow the material with more potential applications in oxidation and reduction reactions.

Aerobic epoxidation of alkene is a green and economical route to produce epoxides. For such reaction, transition metal complexes exhibit favorable catalytic activity. In this work, NH2-MIL-101, a stable metal–organic framework (MOF) material with large surface area and high pore volume, was functionalized with pyridine-2,6-dicarbaldehyde and Co(NO3)2, to realize the immobilization of Co(II) via imine–pyridine–carbonyl (N,N,O) tridentate ligands bonding to MOF skeleton. The modified materials were applied as heterogeneous catalysts for the aerobic epoxidation of cyclohexene at ambient temperature, and multiple factors were studied to explore their influences on catalytic effects. Under the optimal reaction conditions, satisfactory substrate conversion and epoxide selectivity were reached. In addition, this catalytic system is suitable for a variety of alkene substrates. Furthermore, recycle experiments and infrared spectroscopy characterization illustrated that the coordination surroundings of Co are altering smoothly during the reaction process, thus having an impact on the performance of catalyst.

Background Studies examining incident heart failure (HF) have been limited to select populations. To examine incident HF with broader generalizability, there is need to assemble a HF-free cohort using a geographically-diverse sample. We aimed to develop and validate a simple medication-based strategy for assembling a HF-free cohort from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. Methods We examined REGARDS participants with ≥6 months of Medicare inpatient and outpatient claims data at the time of the baseline in-home study examination. To assemble a HF-free cohort, we identified and excluded participants taking HF-specific medications. To validate this approach, we evaluated event rates among this cohort and assessed diagnostic performance using Medicare claims-based definitions of HF as the referent standard. Results Among 28,884 eligible participants, 3125 were excluded from the proposed HF-free cohort, leaving a total of 25,759 (89%) participants. Depending on the Medicare definition used as the referent, the negative predictive value of this approach ranged from 95.0–99.2%. Negative predictive value was stable across age, sex, and race strata. Conclusions The approach to assemble a HF-free cohort in REGARDS can serve as the basis for future studies to examine incident HF in REGARDS and similar studies.

Background There is a paucity of human data on exposure to blast traumatic brain injury (bTBI) and the corresponding systemic cytokine immune response at later time points (i.e., months, years) post-injury. Methods We conducted a repeated measures, case-control study, examining associations of serum levels of pro- and anti-inflammatory cytokines, measured both pre- and post-deployment with having mild and moderate/severe bTBI. Utilizing serum from the Department of Defense Serum Repository cytokines were measured via an ELISA-based array for 15 cytokines. We compared pre- vs. post-levels among mild cases, moderate/severe cases, and controls and carried out case-control comparisons, using paired t- tests and generalized linear models. Results The average time between bTBI and post-deployment/bTBI serum among cases was 315.8 days. From pre- to post-deployment/bTBI, levels of interleukin 8 (IL-8) were decreased among both mild cases (μ = − 83.43 pg/ml; s.e. = 21.66) and moderate/severe cases (μ = − 107.67 pg/ml; s.e. = 28.74 pg/ml), while levels increased among controls (μ = 32.86 pg/ml; s.e. = 30.29). The same pattern occurred for matrix metallopeptidase 3 (MMP3), with levels decreasing for moderate/severe cases (μ = − 3369.24 pg/ml; s.e. = 1701.68) and increasing for controls (μ = 1859.60 pg/ml; s.e. = 1737.51) from pre- to post-deployment/bTBI. Evidence was also suggestive of case-control differences, from pre- to post-deployment/bTBI for interleukin 1 alpha (IL-1α), interleukin 4 (IL-4), and interleukin 6 (IL-6) among moderate/severe cases. Conclusion The findings of this longitudinal study indicate that in the chronic phase of bTBI, levels of IL-8 and MMP3 may be substantially lower than pre-injury. These results need confirmation in other studies, potentially those that account for treatment differences, which was not possible in our study.

Derivatives of oxazine dyes were synthesized on mulitigram scales via efficient synthetic strategies. One practical route was selected to prepare compounds 6, 9 and 10, especially water-soluble compound 6 was obtained in better yield than reported, and compound 10 was insoluble in aqueous media in absence of phenolic-OH. Compounds 3 and 9 were found to be clear pH-dependent between pH = 4.0 and 10.0, and could be used as acid-base indicators to measure intracellular pH. Compounds 6, 9, 10 all have carboxylic acid functionalities, which could be activated and used to conjugate the dyes to biomolecules. In addition, compounds 6 and 9 with good solubility in aqueous media were used to develop a simple, quick, safe, highly sensitive staining method to detect PHAs-producing bacteria on heat-fixed smears, which was confirmed by fluorescence images of PHAs granules of bacteria.

A new type of bar-cropping process, termed the pre-shearing cropping process, which can improve billet cross-section quality has been proposed in this study. The new cropping process was realized by using a servo-controlled press. A low-carbon steel 20Cr as-received and a medium-carbon steel SCM435 as-annealed were used to test the process. A group of pre-shearing cropping experiments was carried out with different pre-shearing values of 6.67, 13.33, 20.00, and 26.67% under a pre-shearing speed of 10 mm/s and a cropping speed of 600 mm/s, and conventional cropping experiments with different cropping speeds of 200, 400, and 600 mm/s were conducted for comparison. The quality of the cropped billets was evaluated quantitatively using the indices of surface flatness, ovality, and incline angle. The effect of cropping speed on the conventional process and the effect of pre-shearing on the pre-shear cropping process were investigated in detail. The experimental results showed that the pre-shearing cropping process could improve the quality of the cropped billets and reduce the maximum cropping load slightly compared with the conventional cropping process. Finally, the mechanism of the pre-shearing cropping process was furtherly analyzed by finite element simulation and tried to be summarized.

Two Wang resin-supported (1R,2R)-(+)-1,2-DPEN(DPEN=diphenylthylenediamine) catalysts were synthesized from cyanuric chloride and trimesoyl chloride, respectively. These two catalysts were characterized by FTIR, TGA and elemental analysis. The results demonstrated that (1R,2R)-(+)-1,2-DPEN was successfully bonded to the surface of Wang resin through the amido linkage. Subsequently, the asymmetric Michael addition of acetone to β-nitrostyrene was employed to evaluate their catalytic performance. It was found that the catalyst generated from trimesoyl chloride exhibited much better catalytic behavior than our previously reported catalyst, likely attributed to the multiple hydrogen-bond interaction between β-nitrostyrene and amide group, which made the catalytic transition intermediates more stable. Under the optimal conditions, 76.1% β-nitrostyrene conversion and 93.8% enantioselectivity were obtained. Finally, the generality of this catalyst was examined with Michael additions of acetone to β-nitroolefins and excellent enantioselectivities(91.9% to 99.9%) were achieved.

Zoledronate is a bisphosphonate that is widely used in the treatment of metabolic bone diseases. However, zoledronate induces significant nephrotoxicity associated with acute tubular necrosis and renal fibrosis when administered intravenously. There is speculation that zoledronate-induced nephrotoxicity may result from its pharmacological activity as an inhibitor of the mevalonate pathway but the molecular mechanisms are not fully understood. In this report, human proximal tubular HK-2 cells and mouse models were combined to dissect the molecular pathways underlying nephropathy caused by zoledronate treatments. Metabolomic and proteomic assays revealed that multiple cellular processes were significantly disrupted, including the TGFβ pathway, fatty acid metabolism and small GTPase signaling in zoledronate-treated HK-2 cells (50 μM) as compared with those in controls. Zoledronate treatments in cells (50 μM) and mice (3 mg/kg) increased TGFβ/Smad3 pathway activation to induce fibrosis and kidney injury, and specifically elevated lipid accumulation and expression of fibrotic proteins. Conversely, fatty acid transport protein Slc27a2 deficiency or co-administration of PPARA agonist fenofibrate (20 mg/kg) prevented zoledronate-induced lipid accumulation and kidney fibrosis in mice, indicating that over-expression of fatty acid transporter SLC27A2 and defective fatty acid β-oxidation following zoledronate treatments were significant factors contributing to its nephrotoxicity. These pharmacological and genetic studies provide an important mechanistic insight into zoledronate-associated kidney toxicity that will aid in development of therapeutic prevention and treatment options for this nephropathy. Electronic supplementary material The online version of this article (doi:10.1007/s00204-017-2048-0) contains supplementary material, which is available to authorized users.

Porcine circovirus-associated disease (PCVAD) caused by porcine circovirus type 2 (PCV2) is an important disease in the global pig industry. Dendritic cells (DCs) are the primary immune cells capable of initiating adaptive immune responses as well as major target cells of PCV2. To determine whether PCV2 affects the immune functions of DCs, we evaluated the expression of endocytosis and co-stimulatory molecules on DCs (CD11c+) from PCV2-infected mouse spleen by flow cytometry (FCM). We also analyzed the main cytokines secreted by DCs (CD11c+) and activation of CD4+ and CD8+ T cells by DCs (CD11c+) through measurement of cytokine secretion, using ELISA. Compared with control mice, PCV2 did not affect the endocytic activity of DCs but it significantly enhanced TNF-α secretion and markedly decreased IFN-α secretion. Subsets of CD40+, MHCII+ CD40+ and CD137L+ CD86+ DCs did not increase obviously, but MHCII+ CD40- and CD137L- CD80+/CD86+ DCs increased significantly in PCV2-infected mouse spleen. Under the stimulation of DCs from PCV2-infected mouse, secretion of IFN-γ by CD4+ and CD8+ T cells and of IL-12 by CD8+ T cells was significantly lower than in control mice, while secretion of IL-4 by CD4+ T cells was remarkably higher. These results indicate that PCV2 modulates cytokine secretion and co-stimulatory molecule expression of DCs, and alters activation of CD4+ and CD8+ T cells by DCs. The immunomodulatory effects of PCV2 on DCs might be related to the host's immune dysfunction and persistent infection with this virus.

A heptamethine cyanine-based near-infrared (NIR) fluorescent probe Cy-1 for hydrosulfide detection was developed, with the response mechanism based on nucleophilic substitution of acryloyl moiety by HS−. Upon addition of NaHS, Cy-1 displayed a rapid fluorescence quenching (excited at 700 nm) and a quick fluorescence enhancement (excited at 544 nm) as well as obvious changes in absorption spectra and color. The response was fast within tens of seconds and could be observed by naked eyes. By contrasting Cy-1 with the reported probe CyAC, the superiority of Cy-1 in selectivity over Cys was demonstrated. Besides, it also exhibited excellent selectivity and sensitivity to HS− over various anions (0.33-μM detection limit). Additionally, this probe was successfully applied in fetal bovine serum samples and imaging of hydrosulfide in living cells.

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A series of metal chlorides supported solid catalysts were prepared by simple wet impregnation method. Their catalytic performances for Friedel-Crafts acylation of toluene with benzoyl chloride were evaluated and the excellent results were obtained over FeCl3/SiO2. These catalysts were characterized by BET, NH3-TPD and FT-IR of pyridine adsorption to clarify the structure-activity relationship. It was found that FeCl3/SiO2 has larger pore size and pore volume than other catalysts, which increased the accessibility of the catalyst. In addition, FeCl3/SiO2 exhibited higher molar ratio of Lewis acid sites and Brφnsted acid sites, which might be another reason for the increase of toluene conversion. Furthermore, the reaction parameters, including temperature, time and molar ratio, were optimized. Under the optimized conditions, 91.2%, conversion and 82.0%, selectivity were obtained. Meanwhile, the generality of the catalyst was demonstrated by the acylations of alkyl substituted aromatics. Finally, the catalyst was reused for four runs with slight loss in catalytic activity, which attributed to the drain of the active component.

Tungstophosphoric acid supported on TiO2 (TPA/TiO2) and iron modified tungstophosphoric acid supported on TiO2 (Fe0.5TPA/TiO2 and FeTPA/TiO2) were prepared and examined for Friedel–Crafts acylation reactions. The obtained results indicated that FeTPA/TiO2 exhibited excellent catalytic performance on the acylation of m-xylene with benzoyl chloride, but inferior results were obtained in the acylation of anisole with acetic anhydride. However, TPA/TiO2 displayed better catalytic activity than others in the later reaction. All the catalysts were characterized by XRD, FT-IR, NH3-TPD, Py-IR and TGA. The obtained results demonstrated that the Lewis acidity of catalysts presented a significant influence on the reaction with benzoyl chloride as acylating agent while the total acidity of catalysts was more important with acetic anhydride as acylating agent. Finally, the reaction mechanisms with two acylating agents over the above catalysts were discussed.

Since 2013, highly pathogenic avian influenza H5N6 viruses have emerged in poultry and caused sporadic infections in humans, increasing global concerns regarding their potential as human pandemic threats. Here, we characterized the receptor-binding specificities, pathogenicities and transmissibilities of three H5N6 viruses isolated from poultry in China. The surface genes hemagglutinin (HA) and neuraminidase (NA) were closely related to the human-originating strain A/Changsha/1/2014 (H5N6). Phylogenetic analyses showed that the HA genes were clustered in the 2.3.4.4 clade, and the NA genes were derived from H6N6 viruses. These H5N6 viruses bound both α-2,3-linked and α-2,6-linked sialic acid receptors, but they exhibited different pathogenicities in mice. In addition, one virus was fully infective and transmissible by direct contact in guinea pigs. These results highlight the importance of monitoring the continual adaptation of H5N6 viruses in poultry due to their potential threat to human health.

A novel and convenient approach for the construction of the bifunctional MIL-101 material bearing sulfonic acid and amino groups was established via the post-synthetic modification. This material possesses high BET surface area (1446 m2/g) and large pore volume (0.77 cm3/g). Significantly, this material could serve as a bifunctional heterogeneous catalyst and was initially employed for one-pot deacetalization-Knoevenagel reaction, exhibiting excellent catalytic performance (yield 99.74%). More importantly, it can be easily recovered and reused at least three times. Finally, our proposed catalytic mechanism indicated that amino and the sulfonic acid groups played a synergistic effect on this one-pot deacetalization-Knoevenagel reaction.

A facile and efficient method for reductive N-alkylation of nitrobenzenes with alcohols catalyzed by the bimetallic catalyst Cu30Cr5/γ-Al2O3, in a fixed-bed reactor, was successfully established. X-ray diffraction, temperature-programmed reduction, and X-ray photoelectron spectroscopy were used to characterize the catalyst. Introduction of Cr to Cu30/γ-Al2O3 was found to substantially enhance the dispersion of Cu0 particles, which are believed to be the active sites for the reductive N-alkylation. The reaction conditions were optimized and a series of alcohols and nitrobenzenes were converted into N-alkylated anilines in more than 90 % yield by use of this catalyst.

The ring-opening reaction of aziridine with alkylamines over a series of ion-exchange resins was investigated. Among these catalysts, D001-CC exhibited excellent catalytic performance. The catalysts were characterized by SEM and N2 adsorption–desorption. The results indicated that the selectivity of N,N-diethylethylenediamine mainly depended on the acidity and S BET of the resins. Strong Bronsted acid sites played an important role on the conversion of aziridine, and the distribution of acid sites on catalyst had a significant effect on the selectivity of N,N-diethylethylenediamine. The reaction parameters, such as reaction time, molar ratio, reaction temperature, and catalyst loading, were also optimized and N,N-diethylethylenediamine was obtained in an excellent yield of 97 %. Furthermore, D001-CC was efficiently recycled five times by simple treatment with large amounts of deionized water and mineral acid. Finally, a series of asymmetric ethylenediamine derivatives were successfully synthesized with this method. Therefore, a simple and versatile process for the synthesis of asymmetric ethylenediamine derivatives has been established over ion-exchange resins.

An impurity was detected in the roflumilast product which was supposed to be N-(3,5-dichloropyridin-4-yl)-4-difluoromethoxy-3-methoxybenzamide. To further verify the impurity structure, this compound was synthesized from 4-difluoromethoxy-3-hydroxybenzaldehyde through O-alkylation, oxidation, chlorination, and amidation reaction and characterized by 1H NMR, 13C NMR, and HPLC–MS. Comparison of the HPLC–MS spectrum of the impurity and the synthesized compound confirmed that they were the same compound. The generation of the impurity was found to be attributed to acetone and iodine in the O-alkylation system.

Several near-infrared (NIR) fluorescent dyes based on aminocyanine have been designed, synthesized, and used for preparation of NIR fluorescent microspheres. Their spectral properties and pH-dependent optical characteristics were investigated. It was found that different substitution at the central position of the dyes led to diverse optical properties, with especially large effects on their spectroscopic properties. Spectroscopic responses of the fluorescent dyes to changes of pH were different. Under acidic conditions, the wavelengths of maximum absorption of the N-substituted cyanine dyes were clearly red shifted. Dyes with an N-substituted piperazidine ring were the most sensitive. The fluorescent microspheres retained the properties of the parent dyes, making them suitable for applications in biological studies.

A series of Cu-based catalysts were prepared and employed in the N-ethylation of ethylenediamine with ethanol in a fixed-bed reactor. Satisfying results were obtained using Cu-Zn-La/Al2O3 as a catalyst. In addition, Cu-Zn-La/SiO2, Cu-Zn-La/Al2O3 and Cu-Zn-La/HZSM-5 were characterized by the Brunauer-Emmett-Teller method (BET), H2- temperature program reduction (H2-TPR), X-ray diffraction (XRD), transmission electron microscopic measurements (TEM) and NH3-temperature programmed desorption (NH3-TPD) in order to investigate the influence of supports on their catalytic performance. It was found that both the BET surface area and the acidity of the support are key factors in the catalytic performance. Moreover, reaction parameters including temperature, hydrogen pressure and liquid hourly space velocity were optimized. Under optimal conditions, a 73.3 % conversion of ethylenediamine and a 71.2 % selectivity of N-ethylethylenediamine were achieved. Finally, the lifetime of the catalysts was evaluated and the reaction proceeded con-tinuously for over 200 h.

A hemicyanine dye with imidazole as the acceptor was designed and prepared as a chemosensor for fluoride anions. The experimental results demonstrated that it is a fluorometric probe for fluoride anion with good sensitivity and high selectivity. This probe showed obvious changes in UV–Vis absorption and fluorescence spectra in the presence of fluoride anions, which are attributed to the deprotonation of N–H on the imidazole moiety with fluoride anions.

An impurity was isolated from crude synthesized roflumilast and characterized by 1H NMR, 13C NMR, and HR-MS, which confirmed the structure as N-(3,5-dichloropyrid-4-yl)-4-difluoromethoxy-3-hydroxybenzamide. To further verify the structure, this compound was synthesized from 4-difluoromethoxy-3-hydroxybenzaldehyde. Comparison of the 1H NMR, 13C NMR, HR-MS, and the HPLC spectrum of the impurity and the authentic sample indicated that this impurity was N-(3,5-dichloropyrid-4-yl)-4-difluoromethoxy-3-hydroxybenzamide. This demonstrated the significance of monitoring the reaction process of roflumilast.

A convenient synthetic method has been developed for the synthesis of roflumilast from 4-difluoromethoxy-3-hydroxybenzaldehyde and bromomethyl cyclopropane via O-alkylation, oxidation and N-acylation. With sodium hydroxide as alkali in the last step, the total yield of roflumilast can be up to 68.3 % and the purity of the target product reached 99.2 %. It was obvious that sodium hydroxide showed more economic advantage for scale-up production than sodium hydride or potassium tert-butoxide.

A series of transition metal-based catalysts, other than Pd or Pt-based catalysts, were investigated for catalytic amination of 2,6-dimethylphenol to 2,6-dimethylaniline in a fixed-bed reactor. Ni–Cu–Cr/γ-Al2O3 yielded satisfactory results with 82.08 % conversion and 47.24 % selectivity. The catalysts were characterized by H2-TPR and TEM, and the results obtained showed that the doped Cu and Cr could promote reduction of Ni/γ–Al2O3 and dispersion of the Ni. Reaction conditions, including reaction temperature, flow rate of hydrogen, and ammonia, were studied.

A modified procedure for synthesis of the side chain of ceftazidime-activated thioester has been established. This key intermediate of ceftazidime was obtained by a more eco-friendly process than conventional methods, and the yield was much higher (up to 92.4 %). It was found that different organic bases (triethylamine or pyridine) used in this reaction had different effects. The reaction conditions were also optimized to make the route more competitive and suitable for large-scale industrial production.

A general process for the cyclization of aminoalcohols to the corresponding amines over Cu–Cr–La/γ-Al2O3 is established in a continuous fixed-bed reactor. The catalyst was characterized by XRD, XPS and NH3-TPD. The doped Cr is found to improve the copper particle dispersion. The addition of La neutralized the strong acid sites and decreased the amount of the acid sites, which facilitated the desorption of amino compounds on the surface of catalysts and inhibited the carbon deposition. Under the optimum conditions, the yields of pyrrolidine, piperidine and piperazine were 99.5, 99.5 and 98.6 %, in order, while the yields of hexahydro-1H-azepine and homopiperazine were 46.5 and 32.7 % due to the unstable seven-membered ring by the cyclization of the corresponding aminoalcohols over Cu–Cr–La/γ-Al2O3.

We present results from theoretical analysis of the phase dynamics in semiconductor optical amplifiers (SOAs). In particular, we focus on an aspect of the ultra-fast phase recovery that currently does not have adequate in-depth theoretical analysis and clear explanation of the physical mechanism. We build up a numerical model to analyze the ultra-fast phase recovery of semiconductor optical amplifiers in details. To investigate the phase response characteristics, we analyze the different contributions to the phase shift, including intra-band effects such as carrier heating, spectral hole burning, and inter-band effects such as carrier depletion. In addition, the impact of the pulses energy on phase shift is also investigated. Based on the analysis of phase response characteristics, we further explain the reason why a delay occurs between gain response and phase response. The analysis results are in good agreement with the reported experimental results. The results presented in this paper are useful for the SOA-based ultra-fast optical signal processing, such as optical switches, optical logic gates, and optical Add/Drop multiplexer.

Several commercially available supports were examined for cyclization of monoethanolamine to aziridine, and SiO2 was found to yield the best results. The obtained results indicated that selectivity of aziridine was mainly influenced by support. The catalysts were characterized by NH3-TPD and XRD. It was found that SiO2 with lower acidity could inhibit the intermolecular condensations, and thus favored the formation of aziridine. The Cs4P2O7 phase was confirmed as the active site in the supported cesium phosphate catalyst. The reaction parameters were also optimized and a yield of 52% aziridine was obtained over 200 h. Thus, a continuous process for the cyclization of monoethanolamine to aziridine has been established.

Human organic cation transporter 3 (OCT3 and SLC22A3) mediates the uptake of many important endogenous amines and basic drugs in a variety of tissues. OCT3 is identified as one of the important risk loci for prostate cancer, and is markedly underexpressed in aggressive prostate cancers. The goal of this study was to identify genetic and epigenetic factors in the promoter region that influence the expression level of OCT3. Haplotypes that contained the common variants, g.-81G>delGA (rs60515630) (minor allele frequency 11.5% in African American) and g.-2G>A (rs555754) (minor allele frequency>30% in all ethnic groups) showed significant increases in luciferase reporter activities and exhibited stronger transcription factor-binding affinity than the haplotypes that contained the major alleles. Consistent with the reporter assays, OCT3 messenger RNA expression levels were significantly higher in Asian (P

A series of chiral pyrrolidine quaternary derivatives were designed and synthesized. It was found that these derivatives are highly efficient organocatalysts for the asymmetric Michael addition reactions of aldehydes and ketones to nitroolefins with high yields (up to 96%), high enantioselectivities (up to 99% ee), and high diastereoselectivities (up to 97:3 dr). Furthermore, catalyst 7a could be recycled without remarkable loss of catalytic activity and stereoselectivity.

A continuous process for reduction of aromatic ketones to the corresponding aromatic alkanes over Cu30Cr10/γ-Al2O3 was established in a fixed-bed reactor. A series of aromatic ketones were examined, and all of the corresponding aromatic hydrocarbons were obtained in more than 95% yield. The catalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and H2-temperature programmed reduction. Cu0 is believed to be the active center of the catalyst. Cr was found to have an important effect on catalytic activity and stability.

A novel co-production process for piperazine and its N-monoalkyl derivatives has been established. N-β-hydroxyethyl-1,2-ethylenediamine and alcohols were used as the starting materials and the process was carried out over Cu–Cr–La/γ-Al2O3 in a fixed-bed reactor. Alcohols acted not only as the solvent but also as the alkylating reagent. The catalyst was characterized by XRD, XPS and BET. The results obtained showed that Cu0 particles in the catalyst were the active sites and doping with La led to enhancement of catalyst activity. Process conditions including reaction temperature, hydrogen pressure, and molar ratio of the reagents were optimized and the distribution of the products was found to be markedly dependent on reaction temperature. Using optimum conditions, piperazine and its N-monoalkyl derivatives were obtained with satisfactory yields and distributions. The catalyst performed well for over 300 h.

A series of Cu-based catalysts were prepared and examined for the reductive amination of triacetoneamine with n-butylamine, thereinto, Cu–Cr–La/γ-Al2O3 showed excellent results. The catalysts were studied by XRD, XPS, H2-TPR and NH3-TPD. It was found that doped Cr remarkably enhanced the activity of Cu/γ-Al2O3 due to better dispersion of Cu0, which is believed to be the active site for the reductive amination. Additionally, it was obvious that introduction of La to Cu–Cr/γ-Al2O3 led to a higher selectivity and longer lifetime. The reaction parameters were optimized and N-butyl-2,2,6,6-tetramethyl-4-piperidinamine was obtained in a yield of 94%. The addition of Cr does not impact obviously on the total acidity of Cu20/γ-Al2O3. However, the La addition to Cu20Cr5/γ-Al2O3 not only decreases the total acidity but also reduces the strength of acid sites. The introduction of La was found to result in a higher selectivity and longer lifetime. The conversion of TAA and selectivity of TEMPBA remained around 99.7 and 94.5% in 120 h.

In this paper, we review the recent progress in the optical signal processing based on the nonlinearity of semiconductor optical amplifiers (SOAs). The four important optical signal processing functional blocks in optical switching are presented, i.e., optical wavelength conversion, optical regeneration, optical logic, and optical format conversion. We present a brief overview of optical wavelength conversion, and focus on various schemes to suppress the slow gain recovery of the SOA and improve the operating speed of the SOA-based optical switches. Optical regeneration including re-amplification, re-shaping and re-timing is also presented. Optical clock recovery that is essential for optical regeneration is reviewed. We also report the recent advances in optical logic and optical format conversion, respectively. After reviewing the four important optical signal processing functional blocks, the review concludes with the future research directions and photonic integration.

A series of chiral pyrrolidine-type quaternary alkylammonium ionic liquids were synthesized and served as efficient catalysts for asymmetric Michael additions of aldehydes and ketones to nitroolefins, and the corresponding adducts were obtained in excellent enantioselectivities (>99% ee) and diastereoselectivities (>99% dr) under solvent-free reaction conditions. Furthermore, the catalyst 7c could be recovered for next run of the reaction with similar yield and selectivity.

Continuous synthesis of N-methylhomopiperazine over Cu–Cr–Mg/γ-Al2O3 has been developed. The doped Cr improves the dispersion of the Cu0 particles and inhibits the generation of CuAl2O4 so that the Cu0 particles are retained as the active sites. Doped Mg neutralizes the strong acid sites in Cu20Cr10Mg10/γ-Al2O3, and led to a decrease in coking side reactions. The reaction parameters were optimized and N-methylhomopiperazine was obtained in a yield of 66%. A continuous process for the preparation of N-methylhomopiperazine and homopiperazine has been developed. The cyclization of N-β-hydroxyethyl-N-methyl-1,3-propanediamine and N-β-hydroxyethyl-N-1,3-propanediamine proceeded effectively over a Cu20Cr10Mg10/γ-Al2O3 catalyst in a fixed-bed reactor.

An all-optical 2R regeneration based on self-induced polarization rotation in a single semiconductor optical amplifier is presented. A theoretical model is built up to simulate the system performance. Experiment evidence is also provided. An extinction ratio improvement of 8.3 dB is obtained at a bit-rate of 10 Gbit/s. In the BER measurements, 6 dB improvement of the power penalty is achieved, clearly demonstrating the feasibility of the proposed scheme. Our approach has a simple structure, and allows photonic integration.

The synthesis of α-amino-β-keto-esters (β-oxo dipeptides) was studied. Corresponding α-amino-β-ketoesters were prepared from BOC-(L)-Valine and BOC-(L)-isoleucine by coupling with (D,L)-threonine hydrochloride and oxidation with Dess-Martin periodinane (DMP) with a total yield of 48% and 38%, respectively.

A series of regiospecific chlorinated fluoresceins have been synthesized by the reaction of the regiospecific chlorinated resorcinols with chlorinated phthalic anhydride. The regioisomers were successfully separated by chromatography. The photophysical properties of the obtained chlorinated fluoresceins were examined and found their absorption and emission maxima at long wavelength with high fluorescence quantum yield. Especially, pH-dependent properties of chlorinated fluoresceins have been studied in detail. These compounds show strongly pH-sensitive range of 3.5-7.0, and have lower pK (a) values than fluorescein. Furthermore, their fluorescent intensity could reach the maximum in the physiological environment of pH range 6.8-7.4. Due to higher fluorescence quantum yield and lower pK (a) values, chlorinated fluoresceins will be expected to be used as excellent pH fluorescent probes for pH measurement of the acidic cell.

The racemization of R-(-)-2-amino-1-butanol in a reaction using Co/γ-Al2O3 catalysts and catalysts modified by Mg or Ca was investigated in this paper. Complete racemization was achieved with a yield of over 83% at using the Mg modified Co/γ-Al2O3 catalyst under optimized reaction conditions of 170°C and 2.5 MPa of H2. The catalysts were thoroughly characterized by XRD, XPS, TPR, SEM and TEM. The addition of Mg and Ca may be advantageous for dispersing and stabilizing the active species of the Co/γ-Al2O3 catalyst, protecting from sintering, significantly improving its catalytic activity and stability.

For a full welded body ball valve, because the last working procedure is the weld, prior to welding, the welding distortion must be accurately predicted to provide preference for welded structure fabrication at the design stage in order to assure spool rotation, valve seal, and non-deformability in active service. Therefore, it is important to select an accurate and efficient method to predict welding distortion. In this study, the finite-element method based on the inherent strain theory was presented to simulate welding distortion in multipass girth-butt welded pipes of different wall thicknesses. For multipass welding, two weld passes at the same layer were combined. The axial distortion of each weld layer was calculated respectively and the radial distortion was calculated for one time. For multipass girth-butt welded pipes of different wall thicknesses, two methods were proposed to predict the axial distortion. The results calculated were compared and better method was confirmed.

The cyclization of N-β-hydroxyethyl-1,3-propanediamine to homopiperazine proceeded effectively over a Cu-Cr-Ba-Al2O3 catalyst in a fixed-bed reactor. The addition of Ba to the Cu-based catalyst improved the dispersion of copper and prevented it from sintering.