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Porous carbons are considered promising for CO2capture due to their high-pressure capture performance, high chemical/thermal stability, and low humidity sensitivity. But, their low-pressure capture performance, selectivity toward CO2over N2, and adsorption kinetics need further improvement for practical applications. Herein, we report a novel dual-templating strategy based on molten salts (LiBr/KBr) and hydrogen-bonded triazine molecules (melamine–cyanuric acid complex, MCA) to prepare high-performance porous carbon adsorbents for low-pressure CO2. The comprehensive investigations of pore structure, microstructure, and chemical structure, as well as their correlation with CO2capture performance, reveal that the dual template plays the role of porogen for multi-hierarchical porous structure based on supermicro-/micro-/meso-/macro-pores and reactant for high N/O insertion into the carbon framework. Furthermore, they exert a synergistic but independent effect on the carbonization procedure of glucose, avoiding the counter-balance between porous structure and hetero-atom insertion. This enables the preferred formation of pyrrolic N/carboxylic acid functional groups and super-micropores of ~ 0.8 nm, while retaining the micro-/meso-/macro-pores (> 1 nm) more than 60% of the total pore volume. As a result, the dual-templated porous carbon adsorbent (MG-Br-600) simultaneously achieves a high CO2capture capacity of 3.95 mmol g−1at 850 Torr and 0 °C, a CO2/N2(15:85) selectivity factor of 31 at 0 °C, and a high intra-particle diffusivity of 0.23 mmol g−1min−0.5without performance degradation over repeated use. With the molecular scale structure tunability and the large-scale production capability, the dual-templating strategy will offer versatile tools for designing high-performance carbon-based adsorbents for CO2capture.

This research effort aims to evaluate the mechanical properties of concrete with two aggregate type, light weight and normal weight at elevated temperatures. To understand the mechanical properties at elevated temperature, normal and light weight concrete of 60 MPa grade was exposed to temperature range 20 to 700ºC under 0%, 20%, 40% load conditions and compressive strength, elastic modulus, thermal strain and transient creep at target temperature were inspected. Experimental results show that light weight concrete has higher compressive strength, although the strength of normal weight concrete degenerated more sharply than the light weight concrete at elevated temperature. Moreover, the thermal strain (0% unstressed) and total strain (20%, 40% stressed) of normal weight concrete was higher than that of light weight concrete. Loading conditions significantly influenced the mechanical properties of normal weight concrete compared to that of light weight concrete at high temperature.

Lysimachia foenum-graecum has been used as an oriental medicine with anti-inflammatory effect. The anti-obesity effect of L. foenum-graecum extract (LFE) was first discovered in our screening of natural product extract library against adipogenesis. To characterize its anti-obesity effects and to evaluate its potential as an anti-obesity drug, we performed various obesity-related experiments in vitro and in vivo. In adipogenesis assay, LFE blocked the differentiation of 3T3-L1 preadipocyte in a dose-dependent manner with an IC50 of 2.5 µg/ml. In addition, LFE suppressed the expression of lipogenic genes, while increasing the expression of lipolytic genes in vitro at 10 µg/ml and in vivo at 100 mg/kg/day. The anti-adipogenic and anti-lipogenic effect of LFE seems to be mediated by the inhibition of PPAR? and C/EBPa expression as shown in in vitro and in vivo, and the suppression of PPAR? activity in vitro. Moreover, LFE stimulated fatty acid oxidation in an AMPK-dependent manner. In high-fat diet (HFD)-induced obese mice (n = 8/group), oral administration of LFE at 30, 100, and 300 mg/kg/day decreased total body weight gain significantly in all doses tested. No difference in food intake was observed between vehicle- and LFE-treated HFD mice. The weight of white adipose tissues including abdominal subcutaneous, epididymal, and perirenal adipose tissue was reduced markedly in LFE-treated HFD mice in a dose-dependent manner. Treatment of LFE also greatly improved serum levels of obesity-related biomarkers such as glucose, triglycerides, and adipocytokines leptin, adiponectin, and resistin. All together, these results showed anti-obesity effects of LFE on adipogenesis and lipid metabolism in vitro and in vivo and raised a possibility of developing LFE as anti-obesity therapeutics.

This paper proposes an optical wireless transfer agent method which realizes the continuous and swift data transfer of optical wireless terminals in optical wireless networks. The unguided wireless channel generally shows frequent link disconnections and propagation delays due to weak wireless links. Specially speaking, optical wireless channels have more vulnerable links and roaming propagation delays relative to the weakness of the previous RF channels due to their low signal connectivity and small geographic coverage. Conventional optical wireless network protocols did not consider any fault models about physical link faults. Consequently, they have shown data transfer inefficiency for both data link control and physical wireless link control. To overcome these optical wireless environmental problems, this paper suggests a new wireless access point (or base station) agent system, which provides wireless or mobile clients with previous link layer protocols compensated.

Hypoxia-induced gene expression is initiated when the hypoxia-inducible factor-1 (HIF-1) α subunit is stabilized in response to a lack of oxygen. An HIF-1α-specific prolyl-hydroxylase (PHD) catalyzes hydroxylation of the proline-564 and/or -402 residues of HIF-1α by an oxygen molecule. The hydroxyproline then interacts with the ubiquitin E3 ligase von Hippel Lindau protein and is degraded by an ubiquitin-dependent proteasome. PHD2 is the most active of three PHD isoforms in hydroxylating HIF-1α. Structural analysis showed that the N-terminal region of PHD2 contains a Myeloid translocation protein 8, Nervy, and DEAF1 (MYND)-type zinc finger domain, whereas the catalytic domain is located in its C-terminal region. We found that deletion of the MYND domain increased the activity of both recombinant PHD2 protein and in vitro-translated PHD2. The zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine augmented the activity of wild-type PHD2-F but not that of PHD2 lacking the MYND domain, confirming that the zinc finger domain is inhibitory. Overexpression of PHD2 lacking the MYND domain caused a greater reduction in the stability and function of HIF-1α than did overexpression of wild-type PHD2, indicating that the MYND domain also inhibits the catalytic activity of PHD2 in vivo.

Human phosphoserine phosphatase (HPSP) regulates the levels of glycine and d-serine, the putative co-agonists for the glycine site of the NMDA receptor in the brain. Here, we describe the first crystal structures of the HPSP in complexes with the competitive inhibitor 2-amino-3-phosphonopropionic acid (AP3) at 2.5 A, and the phosphate ion (Pi) and the product uncompetitive inhibitor l-serine (HPSP.l-Ser.Pi) at 2.8 A. The complex structures reveal that the open-closed environmental change of the active site, generated by local rearrangement of the alpha-helical bundle domain, is important to substrate recognition and hydrolysis. The maximal extent of this structural rearrangement is shown to be about 13 A at the L4 loop and about 25 degrees at the helix alpha3. Both the structural change and mutagenesis data suggest that Arg-65 and Glu-29 play an important role in the binding of the substrate. Interestingly, the AP3 binding mode turns out to be significantly different from that of the natural substrate, phospho-l-serine, and the HPSP.l-Ser.Pi structure provides a structural basis for the feedback control mechanism of serine. These analyses allow us to provide a clear model for the mechanism of HPSP and a framework for structure-based drug development.

The nonstructural protein 3 (NS3) of the hepatitis C virus (HCV) is a bifunctional protein with protease and helicase activities. Nonstructural protein 4A (NS4A) is preceded by NS3 and augments the proteolytic activity of NS3 through protein–protein interaction. The central domain of NS4A has been shown to be sufficient for the enhancement of the NS3 protease activity. However, investigations on the roles of the N-terminal and the C-terminal regions of NS4A have been hampered by the difficulty of purification of full-length NS4A, a polypeptide that contains highly hydrophobic amino acid residues. Here we report a procedure by which one can produce and purify an active, full-length NS4A using maltose-binding protein fusion method. The full-length NS4A fused to the maltose binding protein is soluble and maintains its NS3 protease-enhancing activity.

Hepatitis C virus (HCV) is the major etiologic agent of non-A, non-B hepatitis. One of the difficulties in developing anti-HCV drugs is the lack of an efficient HCV cultivation system. We have generated an artificial surrogate virus suitable for testing the antiviral effects of drugs affecting HCV protease NS3, an enzyme believed to be essential for HCV proliferation. The surrogate virus genome is composed of most of the poliovirus genome and HCV protease NS3 and an NS3-specific cleavage site. The activity of HCV protease NS3 is required for proliferation of this chimeric virus. The antiviral efficacy of HCV protease inhibitors can, therefore, be evaluated by examining the effects of the drugs on the surrogate virus proliferation.

The author reflects on the performance of the service sector in South Korea. He asserts that the government initiatives have not raised the competitiveness of service industries. He inflects that the factor of industrial efficiency has been disregarded in the sector, thus there are conflicts of interest among companies. He suggests that the service sector needs for fundamental reform including structural changes to help advance the service sector itself and turn it into an economic engine.