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Trimethylbenzenes (Interagency Science Discussion Draft)

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The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Emission reduction potential in a light-duty diesel engine fueled by JP-8

Authors: Lee, J; Lee, J; Chu, S; Choi, H; Min, K (2015) HERO ID: 3017974

[Less] In this research, the effects of EGR (exhaust gas recirculation) and multiple injection strategy with . . . [More] In this research, the effects of EGR (exhaust gas recirculation) and multiple injection strategy with two pilots on the emissions and combustion characteristics of JP-8 fueled light-duty diesel engine were systemically investigated. Also, the potential of reducing NOx (nitrogen oxides) and PM (particulate matter) emissions with JP-8 in a light-duty diesel engine was evaluated. To understand the combustion phenomenon of JP-8, two different injection modes (single injection and multiple injection with two pilots) were applied. Under the single injection mode, the difference in the ignition delay between using JP-8 and diesel fuel became clear. Differently, under multiple injections with two pilots, the ignition delays of both cases were nearly the same due to the higher in the cylinder temperature cause by the combustion of the pilot injections. Finally, under multiple injection mode, more EGR (exhaust gas recirculation) could be applied to JP-8 combustion than in conventional diesel combustion while maintaining the same mass fraction burned 50% (MFB 50) to attain the same fuel conversion efficiency. As a result, NOx and PM emissions could be reduced by half when using JP-8 without decreasing the fuel conversion efficiency. (C) 2015 Elsevier Ltd. All rights reserved.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Mesoporous calcium-silicon xerogels with mesopore size and pore volume influence hMSC behaviors by load and sustained release of rhBMP-2

Authors: Song, W; Li, X; Qian, Jun; Lv, G; Yan, Y; Su, J; Wei, Jie (2015) International Journal of Nanomedicine 10:1715-1726. HERO ID: 2898472

[Less] Mesoporous calcium-silicon xerogels with a pore size of 15 nm (MCS-15) and pore volume of 1.43 cm(3)/g . . . [More] Mesoporous calcium-silicon xerogels with a pore size of 15 nm (MCS-15) and pore volume of 1.43 cm(3)/g were synthesized by using 1,3,5-mesitylene (TMB) as the pore-expanding agent. The MCS-15 exhibited good degradability with the weight loss of 50 wt% after soaking in Tris-HCl solution for 56 days, which was higher than the 30 wt% loss shown by mesoporous calcium-silicon xerogels with a pore size of 4 nm (MCS-4). The pore size and pore volume of MCS-15 had significant influences on load and release of recombinant human bone morphogenetic protein-2 (rhBMP-2). The MCS-15 had a higher capacity to encapsulate a large amount of rhBMP-2; it could adsorb 45 mg/g of rhBMP-2 in phosphate-buffered saline after 24 hours, which was more than twice that with MCS-4 (20 mg/g). Moreover, the MCS-15 system exhibited sustained release of rhBMP-2 as compared with MCS-4 system (showing a burst release). The MCS-15/rhBMP-2 system could promote the proliferation and differentiation of human mesenchymal stem cells, showing good cytocompatibility and bioactivity. The results indicated that MCS-15, with larger mesopore size and higher pore volume, might be a promising carrier for loading and sustained release of rhBMP-2, which could be used as bone repair material with built-in osteoinduction function in bone reconstruction.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

EXPERIMENTAL STUDY ON INJECTION AND MACROSCOPIC SPRAY CHARACTERISTICS OF ETHYL OLEATE, JET FUEL AND THEIR BLEND ON A DIESEL ENGINE COMMON RAIL SYSTEM

Authors: Duan, Y; Han, D; Li, P; Wang, C; Lin, He; Huang, Z (2015) HERO ID: 3044661

[Less] Injection and macroscopic spray characteristics of ethyl oleate, jet fuel, and ethyl oleate-jet fuel . . . [More] Injection and macroscopic spray characteristics of ethyl oleate, jet fuel, and ethyl oleate-jet fuel blend are investigated on a common rail injection system, with changed injection pressures and ambient pressures. The volumetric and mass injection rates, as well as the macroscopic spray parameters, such as the spray penetration distance, spray cone angle, projected spray area, spray front velocity, maximum spray width, and light intensity level of different test fuels, are analyzed in detail. It is found that fuel property places an important influence on injection characteristics. Similarly, the fuel physical properties also lead to some distinctions in the macroscopic spray parameters.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Microspore culture reveals complex meiotic behaviour in a trigenomic Brassica hybrid

Authors: Mason, AS; Takahira, J; Atri, C; Samans, B; Hayward, A; Cowling, WA; Batley, J; Nelson, MN (2015) HERO ID: 3044686

[Less] BACKGROUND: Development of synthetic allohexaploid Brassica (2n = AABBCC) would be . . . [More] BACKGROUND: Development of synthetic allohexaploid Brassica (2n = AABBCC) would be beneficial for agriculture, as allelic contributions from three genomes could increase hybrid vigour and broaden adaptation. Microspore culture of a near-allohexaploid hybrid derived from the cross (B. napus × B. carinata) × B. juncea was undertaken in order to assess the frequency and distribution of homologous and homoeologous crossovers in this trigenomic hybrid. SNP and SSR molecular markers were used to detect inheritance of A, B and C genome alleles in microspore-derived (MD) progeny. SNP allele copy number was also assessed. The MD progeny were also compared to progeny derived by self-pollination and open-pollination for fertility (estimated by self-pollinated seed set and pollen viability) and DNA ploidy (measured by flow cytometry).

RESULTS: In the trigenomic hybrid, homologous chromosome pairs A(j)-A(n), B(j)-B(c) and C(n)-C(c) had similar meiotic crossover frequencies and segregation to that previously observed in established Brassica species, as demonstrated by marker haplotype analysis of the MD population. Homoeologous pairing between chromosomes A1-C1, A2-C2 and A7-C6 was detected at frequencies of 12-18 %, with other homoeologous chromosome regions associating from 8 % (A3-C3) to 0-1 % (A8-C8, A8-C9) of the time. Copy number analysis revealed eight instances of additional chromosomes and 20 instances of chromosomes present in one copy in somatically doubled MD progeny. Presence of chromosome A6 was positively correlated with self-pollinated seed set and pollen viability in the MD population. Many MD progeny were unable to produce self-pollinated seed (76 %) or viable pollen (53 %), although one MD plant produced 198 self-pollinated seeds. Average fertility was significantly lower in progeny obtained by microspore culture than progeny obtained by self-pollination or open-pollination, after excluding MD progeny which had not undergone chromosome doubling.

CONCLUSIONS: Based on SNP data analysis of the microspore-derived progeny, crossover frequency per chromosome in the allohexaploid hybrid was found to be similar to that in established Brassica species, suggesting that the higher chromosome number did not significantly disrupt cellular regulation of meiosis. SNP allele copy number analysis revealed the occurrence not only of homoeologous duplication/deletion events but also other cryptic duplications and deletions that may have been the result of mitotic instability. Microspore culture simplified the assessment of chromosome behaviour in the allohexaploid hybrid but yielded progeny with lower fertility and a greater range of ploidy levels compared to progeny obtained by self- or open-pollination.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Evaluation of Optimal Pore Size of (3-Aminopropyl)triethoxysilane Grafted MCM-41 for Improved CO2 Adsorption

Authors: Liu, Z; Teng, Y; Zhang, Kai (2015) HERO ID: 3044692

[Less] An array of new MCM-41 with substantially larger average pore diameters was synthesized through adding . . . [More] An array of new MCM-41 with substantially larger average pore diameters was synthesized through adding 1,3,5-trimethylbenzene (TMB) as the swelling agent to explore the effect of pore size on final adsorbent properties. The pore expanded MCM-41 was also grafted with (3-Aminopropyl)triethoxysilane (APTES) to determine the optimal pore size for CO2 adsorption. The pore-expanded mesoporous MCM-41s showed relatively less structural regularity but significant increments of pore diameter (4.64 to 7.50 nm); the fraction of mesopore volume also illustrated an increase. The adsorption heat values were correlated with the order of the adsorption capacities for pore expanded MCM-41s. After amine functionalization, the adsorption capacities and heat values showed a significant increase. APTES-grafted pore-expanded MCM-41s depicted a high potential for CO2 capture regardless of the major drawback of the high energy required for regeneration.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Effect of stereo-configurational difference of carbohydrate model compound on the reaction with active oxygen species under oxygen delignification conditions

Authors: Nakagawa, A; Yokoyama, T; Matsumoto, Y (2015) HERO ID: 3044715

[Less] We examined how the stereo-configurational difference affects the reaction of a carbohydrate model compound . . . [More] We examined how the stereo-configurational difference affects the reaction of a carbohydrate model compound with active oxygen species (AOS) generated in situ by reactions between O-2 and a phenolic compound under conditions similar to those of oxygen delignification or with oxyl anion radical, the conjugate base of hydroxyl radical, generated by the decomposition of H2O2 under alkaline conditions. As the phenolic compound, 2,4,6-trimethylphenol or 4-hydroxy-3-methoxybenzyl alcohol (vanillyl alcohol) was used. The carbohydrate model compounds employed were methyl beta-d-glucopyranoside (MGP beta) and its 4 epimers, methyl alpha-d-glucopyranoside (MGP alpha), methyl beta-d-mannopyranoside (MMP), methyl beta-d-allopyranoside (MAP), and methyl beta-d-galactopyranoside (MGaP). Their stabilities were in the order of MGP alpha > MGP beta > MMP > MGaP > MAP, indicating that the reactivity of the carbohydrate model compound is significantly dependent on where the stereo-configurational difference is. Only the co-existence of MMP enhanced the degradation of MGP beta, when a pair of MGP beta and another carbohydrate model compound was reacted with the AOS. This result suggests that the profile of AOS in the system is dependent not only on the type of phenolic compound, the generator of AOS, but also on that of the carbohydrate model compound.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Synthesis, Crystal Structure, Spectroscopic Characterization and Thermal Stability Properties of a Trinuclear Zinc(II) Complex

Authors: Li Chang-Hong; Li Wei; Hu Han-Xiang; Hu Bo-Nian (2015) HERO ID: 3044683

[Less] A new trinuclear zinc complex Zn-3(2,2'-biPY)(2)(3,5-DMBA)(6).(H2O)1,5 (1) with 3,5-dimethylbenzoic . . . [More] A new trinuclear zinc complex Zn-3(2,2'-biPY)(2)(3,5-DMBA)(6).(H2O)1,5 (1) with 3,5-dimethylbenzoic acid (3,5-DMBA) and 2,2'-bipyridine as ligands has been synthesized in the mixed solvents of methanol and water. It crystallizes in the monoclinic space group C2/c with a = 31.1497(15), b = 11.7576(6), c = 20.9049(10) A, = 118.4550(10), V = 6731.4(6) angstrom(3), D-c, = 1.412 g/cm(3), Z = 4, F(000) = 2972, GOOF = 1.069, the final R= 0.0667 and wR= 0.1917. The whole molecule consists of three zinc ions, six 3,5-DMBA molecules, two 2,2'-bipyridine molecules and one and half water molecules, in which three zinc ions are bridged by six mu(2)-eta(1):eta(0)-carboxylate groups of 3,5-DMBA". The Zn(1) atom is centrosymmetric, and adopts a distorted octahedral ZnO6 geometry, while the Zn(2) gives a distorted square pyramidal ZnO3N2 geometry. The spectroscopic characterization and thermal stability properties of the complex were investigated.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Mutations in transcription factor Mrr2p contribute to fluconazole resistance in clinical isolates of Candida albicans

Authors: Wang, Y; Liu, JY; Shi, C; Li, WJ; Zhao, Y; Yan, L; Xiang, MJ (2015) HERO ID: 3044641

[Less] The Candida albicans zinc cluster proteins are a family of transcription factors (TFs) that play essential . . . [More] The Candida albicans zinc cluster proteins are a family of transcription factors (TFs) that play essential roles in the development of antifungal drug resistance. Gain-of-function mutations in several TFs, such as Tac1p, Mrr1p and Upc2p, have been previously well documented in azole-resistant clinical C. albicans isolates. Mrr2p (multidrug resistance regulator 2) is a novel TF controlling expression of the ABC transporter gene CDR1 and mediating fluconazole resistance. In this study, the relationship between naturally occurring mutations in MRR2 and fluconazole resistance in clinical C. albicans isolates was investigated. Among a group of 20 fluconazole-resistant clinical C. albicans and 10 fluconazole-susceptible C. albicans, 12 fluconazole-resistant isolates overexpressed CDR1 by at least two-fold compared with the fluconazole-susceptible isolates. Of these 12 resistant isolates, three (C7, C9, C15) contained 11 identical missense mutations, 6 of which occurred only in the azole-resistant isolates. The contribution of these mutations to CDR1 overexpression and therefore to fluconazole resistance was further verified by generating recombinant strains containing the mutated MRR2 gene. The mutated MRR2 alleles from isolate C9 contributed to an almost six-fold increase in CDR1 expression and an eight-fold increase in fluconazole resistance; the missense mutations S466L and T470N resulted in an increase in CDR1 expression of more than two-fold and a four-fold increase in fluconazole resistance. In contrast, the other four missense mutations conferred only two- to four-fold increases in fluconazole resistance, with no significant increase in CDR1 expression. These findings provide some insight into the mechanism by which MRR2 regulates C. albicans multidrug resistance.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Density functional theory calculations on the active site of biotin synthase: mechanism of S transfer from the Fe2S2 cluster and the role of 1st and 2nd sphere residues

Authors: Rana, A; Dey, S; Agrawal, A; Dey, A (2015) HERO ID: 3044646

[Less] Density functional theory (DFT) calculations are performed on the active site of biotin synthase (BS) . . . [More] Density functional theory (DFT) calculations are performed on the active site of biotin synthase (BS) to investigate the sulfur transfer from the Fe2S2 cluster to dethiobiotin (DTB). The active site is modeled to include both the 1st and 2nd sphere residues. Molecular orbital theory considerations and calculation on smaller models indicate that only an S atom (not S(2-)) transfer from an oxidized Fe2S2 cluster leads to the formation of biotin from the DTB using two adenosyl radicals generated from S-adenosyl-L-methionine. The calculations on larger protein active site model indicate that a 9-monothiobiotin bound reduced cluster should be an intermediate during the S atom insertion from the Fe2S2 cluster consistent with experimental data. The Arg260 bound to Fe1, being a weaker donor than cysteine bound to Fe2, determines the geometry and the electronic structure of this intermediate. The formation of this intermediate containing the C9-S bond is estimated to have a ΔG(≠) of 17.1 kcal/mol while its decay by the formation of the 2nd C6-S bond is calculated to have a ΔG(≠) of 29.8 kcal/mol, i.e. the 2nd C-S bond formation is calculated to be the rate determining step in the cycle and it leads to the decay of the Fe2S2 cluster. Significant configuration interaction (CI), present in these transition states, helps lower the barrier of these reactions by ~30-25 kcal/mol relative to a hypothetical outer-sphere reaction. The conserved Phe285 residue near the Fe2S2 active site determines the stereo selectivity at the C6 center of this radical coupling reaction. Reaction mechanism of BS investigated using DFT calculations. Strong CI and the Phe285 residue control the kinetic rate and stereochemistry of the product.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Oil Recovery from Water under Environmentally Relevant Conditions Using Magnetic Nanoparticles

Authors: Mirshahghassemi, S; Lead, JR (2015) HERO ID: 3044648

[Less] Large oil spills and oily wastewater discharges from ships and industrial activities can have serious . . . [More] Large oil spills and oily wastewater discharges from ships and industrial activities can have serious impacts on the environment with potentially major economic impacts. Current oil remediation techniques are inefficient and may have deleterious environmental consequences. However, nanotechnology offers a new route to potentially remediate oil pollution. In this study, a cheap and facile hydrothermal method was developed to synthesize polyvinylpyrrolidone-coated magnetite nanoparticles to separate a reference MC252 oil from oil-water mixture under environmentally relevant conditions. Fluorescence and Proton nuclear magnetic resonance spectroscopy results showed near 100% oil removal from oil-water mixture in the ultrapure water under optimum condition. Based on gas chromatography-mass spectrometry data, approximately 100% of lower molecular mass alkanes (C9-C21) were removed within 10 min of magnetic separation and by increasing the separation time to 40 min, greater than 67% of C22-25 alkanes were removed. Moreover, nanoparticles removed near 100% oil from synthetic seawater solutions in the presence and absence of fulvic acid showing excellent oil removal capacity of the nanoparticles under different conditions. Results show that these nanoparticles can be utilized to remove oil over a short time with a high removal efficiency under environmentally relevant conditions.