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Recently, carbon dioxide capture and conversion, along with hydrogen from renewable resources, provide an alternative approach to synthesis of useful fuels and chemicals. People are increasingly interested in developing innovative carbon dioxide hydrogenation catalysts, and the pace of progress in this area is accelerating. Accordingly, this perspective presents current state of the art and outlook in synthesis of light olefins, dimethyl ether, liquid fuels, and alcohols through two leading hydrogenation mechanisms: methanol reaction and Fischer-Tropsch based carbon dioxide hydrogenation. The future research directions for developing new heterogeneous catalysts with transformational technologies, including 3D printing and artificial intelligence, are provided. Carbon dioxide (CO 2 ) capture and conversion provide an alternative approach to synthesis of useful fuels and chemicals. Here, Ye et al. give a comprehensive perspective on the current state of the art and outlook of CO 2 catalytic hydrogenation to the synthesis of light olefins, dimethyl ether, liquid fuels, and alcohols.

Background: The brain is one of the most vulnerable metastasis sites in lung cancer; approximately 40–50% of lung cancer patients develop brain metastasis during the disease course, contributing to the poor prognosis and high mortality of lung cancer patients. Therefore, it is important to clarify the molecular mechanism underlying brain metastasis of lung cancer for improving the overall survival of lung cancer patients. The present study aimed to investigate the potential role of blood-brain barrier (BBB) permeability in the development of brain metastasis of lung cancer and explore the effect of aspirin in an in-vitro BBB model. Methods: An in-vitro BBB model was established. The expression of heat shock protein 70 (HSP 70), zonula occludens-1 (ZO-1), and occludin in rat brain microvascular endothelial cells was detected using Western blot at different time points following the administration of aspirin. Results: HSP70, ZO-1, and occludin expressions did not show significant changes before aspirin administration, but increased noticeably after aspirin administration. Tumor necrosis factor-α (TNF-α) could significantly attenuate the increased expression of these proteins induced by aspirin. Additionally, TNF-α also significantly reversed the aspirin-induced decrease of BBB permeability. Conclusions: Aspirin may inhibit brain metastasis of lung cancer in a time-dependent manner via upregulating tight junction proteins to reduce BBB permeability, and this effect can be reversed by TNF-α.

Chronic stress as a known risk factor leads to hyperactivity of the hypothalamus-pituitary-adrenal (HPA) axis in both depression and anxiety. However, the stress-induced dysfunction of the HPA axis in these disorders especially the common and unique molecular dysregulations have not been well-explored. Previously, we utilized a chronic mild stress (CMS) paradigm to segregate and gain depression-susceptible, anxiety-susceptible, and insusceptible groups. In this study, we continue to examine the possible protein expression alterations of the hypothalamus as the center of the HPA axis in these three groups by using a proteomic approach. Though isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative analysis, a total of 593 dysregulated proteins were identified. These were potentially associated with vulnerability and adaptability of CMS-caused depression or anxiety and therefore might become novel investigative protein targets. Further independent analysis using parallel reaction monitoring (PRM) indicated that 5, 7, and 21 dysregulated proteins were specifically associated with depression-susceptible, anxiety-susceptible, and insusceptible groups, respectively, suggesting that the same CMS differently affected the regulation system of the rat hypothalamic proteome. In summary, the current proteomic research on the hypothalamus provided insights into the specific and common molecular basis for the HPA dysfunction mechanisms that underlie resiliency and vulnerability to stress-induced depression or anxiety.

As many people rely on e-mail communications for business and everyday life, Internet e-mail worms constitute one of the major security threats for our society. Unlike scanning worms such as Code Red or Slammer, e-mail worms spread over a logical network defined by e-mail address relationships, making traditional epidemic models invalid for modeling the propagation of e-mail worms. In addition, we show that the topological epidemic models presented by M. Boguna, et al. (2000) largely overestimate epidemic spreading speed in topological networks due to their implicit homogeneous mixing assumption. For this reason, we rely on simulations to study e-mail worm propagation in this paper. We present an e-mail worm simulation model that accounts for the behaviors of e-mail users, including e-mail checking time and the probability of opening an e-mail attachment. Our observations of e-mail lists suggest that an Internet e-mail network follows a heavy-tailed distribution in terms of node degrees, and we model it as a power-law network. To study the topological impact, we compare e-mail worm propagation on power-law topology with worm propagation on two other topologies: small-world topology and random-graph topology. The impact of the power-law topology on the spread of e-mail worms is mixed: E-mail worms spread more quickly on a power-law topology than on a small-world topology or a random-graph topology, but immunization defense is more effective on a power-law topology.

A new method, termed metagenomic gene specific multi-primer PCR (MGSM-PCR), is presented that uses multiple gene specific primers derived from an isolated gene from a constructed metagenomic library rather than degenerate primers designed based on a known enzyme family. The utility of MGSM-PCR was shown by applying it to search for homologues of the glycoside hydrolase family 9 cellulase in metagenomic DNA. The success of the multiplex PCR was verified by visualizing products on an agarose gel following gel electrophoresis. A total of 127 homologous genes were amplified with combinatorial multi-primer reactions from 34 soil DNA samples. Multiple alignments revealed extensive sequence diversity among these captured sequences with sequence identity varying from 26 to 99.7%. These results indicated that significantly diverse homologous genes were indeed readily accessible when using multiple metagenomic gene specific primers.

Light hydrocarbons are very important fossil resources used as clean fuels and raw materials for the chemical industry as well as in our daily life. Synthesis of light hydrocarbons from various renewable resources such as biomass and maximizing their utilization value are of great importance. Hydrogenation of CO or CO2 and dehydrogenation of light paraffins to corresponding olefins are convenient technologies to fulfill this purpose. During those conversion processes, highly efficient catalyst systems could play significant roles. Thus, in this study, different catalyst systems were developed to cover the hydrogenation of CO to light olefins, hydrogenation of CO2 to methane as well as dehydrogenation of ethane to ethylene. For the hydrogenation of CO to light olefins via the Fischer-Tropsch process, the effects of Cu on Fe-Mn based catalysts system were investigated. Catalysts with different Cu loadings were synthesized and evaluated. The 3.0 wt% Cu promoted Fe-Mn catalyst demonstrated an activity as high as 3.58 μmolCO·gcat−1·s−1. The corresponding conversion of CO and selectivity to light olefins are 96.9 % and 40.1 %, respectively. All prepared catalysts showed superior efficiency of carbon utilization with CO2 selectivity as low as 23.0 % due to the hindered water-gas shift (WGS) reaction. For the hydrogenation of CO2 to methane, two Ni/SiO2 catalysts with different structures and catalytic properties were prepared by different methods. The Ni/SiO2-AEM prepared by ammonia-evaporation method with a lamellar structure of nickel phyllosilicate achieved a high activity for selectively converting CO2 to CH4 and superior stability during the 160 hours evaluation under high space velocity at 370 °C. For the dehydrogenation of ethane to ethylene, Cr-based catalysts supported by HZSM-5, SBA-15, SiO2 and γ-Al2O3 were synthesized and evaluated under comparable conditions. The Cr/HZSM-5 catalyst demonstrated an C2H6 converting activity of 1.47 μmol·gcat-1·s-1 with the corresponding C2H6 conversion and C2H4 selectivity to be 37.3% and 90%, respectively. The effects of different support materials on the nature of the active Cr species were also determined in terms of the interactions between CrOx and supports.

Mounting studies have demonstrated that RAB3GAP1 expression is modified in brain diseases with multiple neurobiological functions and processes and acts as a potentially significant target. However, the cellular and molecular events arising from RAB3GAP1 dysexpression are still incompletely understood. In this work, underexpression and overexpression of RAB3GAP1 were first induced into cultured mouse cortical neurons by transfection with lentivirus plasmids. Then we globally explored the effects of RAB3GAP1 dysexpression on the proteome of the neurons through the use of isobaric tag for relative and absolute quantitation (iTRAQ)-based quantitative proteomics with bioinformatics. A total of 364 proteins in the RAB3GAP1-underexpression group and 314 proteins in the RAB3GAP1-overexpression group were identified to be differentially expressed. Subsequent bioinformatics analysis indicated that the proteome functional expression profiles induced by RAB3GAP1 underexpression and overexpression were different, suggesting the potential differences in biological processes and cellular effects. Subsequent intergroup cross-comparison revealed some candidate target proteins regulated directly by RAB3GAP1. Further parallel reaction monitoring (PRM) analysis illustrated that Sub1, Ssrp1, and Top1 proteins might serve as new potentially important linkers in the RAB3GAP1-mediated autophagy pathway in the cortical neurons. Collectively, the current proteomics data furnished new valuable insights to better understand the regulatory molecular mechanism of neuronal RAB3GAP1.

Due to the inherent and unavoidable defects of the steel structure of the bridge, CTOD (crack tip opening displacement) tests were carried out on E43 steel specimen under a condition of fatigue. The results provide an experimental base and computing foundations for the bridge steel-using. In this paper, CTOD fatigue pre-cracking tests for E43 steel was studied.

Recently, carbon dioxide capture and conversion, along with hydrogen from renewable resources, provide an alternative approach to synthesis of useful fuels and chemicals. People are increasingly interested in developing innovative carbon dioxide hydrogenation catalysts, and the pace of progress in this area is accelerating. Accordingly, this perspective presents current state of the art and outlook in synthesis of light olefins, dimethyl ether, liquid fuels, and alcohols through two leading hydrogenation mechanisms: methanol reaction and Fischer-Tropsch based carbon dioxide hydrogenation. The future research directions for developing new heterogeneous catalysts with transformational technologies, including 3D printing and artificial intelligence, are provided.