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Measurements of the coexistence curve and turbidity were made on different molecular mass samples of the branched polymer-solvent system eight-arm star polystyrene in methylcyclohexane near its critical point. We confirmed that these systems belong in the Ising universality class. The location of the critical temperature and composition as well as the correlation length, susceptibility, and coexistence curve amplitudes were found to depend on molecular mass and the degree of branching. The coexistence curve diameter had an asymmetry that followed a “complete scaling” approach. All the coexistence curve data could be scaled onto a common curve with one adjustable parameter. We found the coexistence curve amplitude to be about 12% larger for branched than linear polystyrenes of the same molecular mass in either solvent cyclohexane or methylcyclohexane. The two-scale-factor universality ratio R was found to be independent of molecular mass or degree of branching. [ABSTRACT FROM AUTHOR]

Dendroctonus rufipennis (Kirby, Coleoptera: Curculionidae) uses pheromone blends containing aggregative components (frontalin, verbenene, 1-methyl-2-cyclohexen-1-ol [MCOL], and seudenol) and an anti-aggregative component (3-methyl-2-cyclohexen-1-one [MCH]) to coordinate attacks against host trees, but little is known about the influence of external stimuli on pheromone production. We conducted feeding experiments followed by pheromone extractions to determine if feeding duration and mate presence affected pheromone production in D. rufipennis. Unfed beetles of both sexes produced very little of any pheromone component. Females fed for 48 h produced significantly more MCH and MCOL compared to those which fed for 24 h. Males fed for 48 h produced significantly less seudenol than those which fed for 24 h. Male presence did not significantly affect female pheromone production. We propose that the pheromone blend produced by beetles transitions from aggregative to anti-aggregative shortly after colonizing a host, regardless of mate presence. [ABSTRACT FROM AUTHOR]

The three cyclohexenone rings of the title compound, C27H33N3O6, adopt slightly distorted envelope conformations, with the C atom bearing two methyl groups as the flap atom in each case. These cyclohexenone mean planes form dihedral angles of 87.41 (11), 70.73 (11) and 70.47 (11)° with the 1,3,5-triazine ring, while the dihedral angle between the cyclohexenone mean planes are 57.52 (12), 23.75 (12) and 53.21 (12)°. In the crystal, molecules are linked via C-H...O hydrogen bonds, forming a three-dimensional network. [ABSTRACT FROM AUTHOR]

Aim: The aim of the present study was to assess the effect of dietary supplementation with different levels of protein on fecal egg counts and hematological parameters in goat kids with subclinical nematodosis under semi-intensive condition. Materials and Methods: 20 goat kids (3-5 months old with an average body weight of 8.90 kg) were randomly allocated to four groups: T1, served as a negative control, without receiving concentrate feed, and T2, T3, and T4 that received concentrate feed containing 16, 20, and 24% digestible crude protein, respectively. The experiment was carried out for 60 days. Results: In this study, protein supplementation had a significant (p<0.05) effect on fecal egg counts even after 15 days; hemoglobin (Hb) (g/dl) after 45 days; total leukocyte count (103/mm3) and total erythrocyte count (106/mm3) after 30 days; packed cell volume (%), lymphocyte (%), and eosinophil (%) after 15 days of supplementation, whereas monocyte (%) and neutrophil (%) values were not significantly influenced by protein supplementation effect during the entire experiment. The values of mean corpuscular volume (fl) were affected significantly (p<0.05, p<0.01) due to protein supplementation after 30 days, mean corpuscular Hb (MCH) (pg) after 45 days, but MCH concentration (g/dl) was not significantly different among the experimental groups during the entire experiment. Conclusion: The dietary supplementation with different levels of protein significantly improved the hematological profiles and inhibited the nematodosis infection in the experimental goat kids. [ABSTRACT FROM AUTHOR]

Despite recent approvals of anti-obesity drugs there is still a high therapeutic need for alternative options with higher efficacy in humans. As part of our MCH-R1 antagonist program for the treatment of obesity, a series of biphenylacetamide HTS hits was evaluated. Several issues of the initial lead structures had to be resolved, such as potency, selectivity over related GPCRs and P-gp efflux limiting brain exposure in this series. We could demonstrate that all parameters can be significantly improved by structural modifications resulting in BI 414 as a potent and orally available MCH-R1 antagonist tool compound with acceptable in vivo efficacy in an animal model of obesity. [ABSTRACT FROM AUTHOR]

Herein a comprehensive study is provided on the asymmetric conjugate addition (ACA) of Grignard reagents to α-substituted cyclic enones. After the elucidation of the optimal experimental conditions, the scope of Grignard reagents and Michael acceptors was examined. Whereas secondary Grignards gave better enantioselectivities with 2-cyclopentenones, both linear and branched Grignard reagents were tolerated for the ACA to 2-methylcyclohexenone. The sequential ACA-enolate trapping, which leads to quaternary stereocenters, was then studied. Thus, many electrophiles have been tested, thereby giving rise to highly functionalized cyclic ketones with contiguous α-quaternary and β-tertiary centers. The present technique is believed to bring a new approach to versatile terpenoid-like skeletons of bioactive natural products. Straightforward derivatizations of enantioenriched saturated cyclic ketones further support the potential of the present methodology in synthesis. [ABSTRACT FROM AUTHOR]

Liquid organic hydrides can act as energy storage from renewable sources in a cycle of hydrogenation and dehydrogenation. In this work, a feasibility study for heat storage by methylcyclohexane dehydrogenation as a system component in a Liquid Organic Reaction Cycle (LORC) is presented. The endothermic dehydrogenation of methylcyclohexane was investigated in a microstructured reactor, in order to supply reaction heat efficiently. The integration of a membrane into the microstructured reactor for in-situ pure hydrogen removal is intended in further studies. In order to obtain an efficient microstructured membrane reactor, basic catalyst studies were performed. For this purpose different catalysts were prepared and applied to the microstructured reactor. A catalyst containing Pt as active metal and Al 2 O 3 as porous support was selected as the most active catalyst and it was further characterized by BET, H 2 chemisorption, SEM, EPMA and ICP-OES. The different catalysts deactivated rapidly by coke formation at the entrance of the microstructured reactor. Carbon black was analyzed on the catalyst surface by Raman spectroscopy. The addition of H 2 or a higher pressure level in the reaction zone delayed the deactivation rate considerably. Therefore, the utilization of a microstructured membrane reactor is beneficial; it provides conditions to reduce coke formation like a higher reaction pressure and continuous H 2 partial pressure in the catalyst zone if sweep gas is absent on the permeate side of the membrane. [ABSTRACT FROM AUTHOR]

This paper presents the investigation of the pressure drop in headers and development of correlation for pressure loss coefficient for single phase flow through round cylindrical headers of parallel MCHXs. The working fluid was compressed air flowing through header with 1–20 m s −1 based on smallest cross section while the velocity through microchannels was in the range 6–30 m s −1 . The experimental results indicate that the pressure loss coefficient of inlet header is a linear function of the ratio of velocities through microchannel tube and header, except for the first two microchannel tubes; the pressure loss coefficient of outlet header is a quadratic function of the ratio of velocities through microchannel tube and header, and decreases as the velocities through upstream microchannel tubes increase. Correlations for predicting pressure drop of inlet header and outlet header are developed and agreement for 98% of experimental data is within a ±15 Pa. [ABSTRACT FROM AUTHOR]

A simple catalytic, redox-neutral access to 3-methylcyclohexenones has been developed via rhodium catalysis in the presence of an amine additive and Ag 2 CO 3 . This process utilized simple aldehydes and acetone as substrates and tolerates a variety of functional groups. Disubstituted phenols were isolated in moderate yields when Cu(OAc) 2 was employed as an oxidant. [ABSTRACT FROM AUTHOR]

In this work a continuous investigation of the thermal behavior of two heavy crude oils, P2 and P4, from Brazilian basin was performed using simultaneous technique TG-DSC-FTIR. In previous publication-Part 1, about these same oils at nitrogen atmosphere, it was identified for P2 sample that the main evolved component was 1-dodecyl-4-octyl-cyclohexane at 450 °C and for P4 sample the main component was evolved at 340 °C referent to 1-methyl cyclohexene. The simultaneous technique TG/FTIR was also performed for the present study in synthetic air atmosphere and was more elucidative than analysis in nitrogen atmosphere. For heavy oil P2, there was identified the presence of carbon dioxide, carbon monoxide and 4-methylcyclohexanone at 382 °C. Whilst for sample P4 the gaseous components evolved at 454 °C were carbon dioxide, carbon monoxide and 1-methylcyclohexene. Also differences in TG analysis for both samples were observed regarding the number of components. In air atmosphere crude oil P2 exhibited three decomposition stages, in nitrogen were only two. Four stages were exhibited on the thermogravimetric curve for oil P4 in synthetic air, while in nitrogen atmosphere there were three stages. Thus, this study has a unique character regarding the use of combined simultaneous techniques as STA/FTIR to identify components in heavy oil which may contribute to upgrade methods referring to crude oil composition. [ABSTRACT FROM AUTHOR]

The antioxidative properties of a novel curcumin analogue (2E,6E)-2,6-bis(3,5-dimethoxybenzylidene)cyclohexanone (MCH) were assessed by several in vitro models, including superoxide anion, hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and PC12 cell protection from H2O2 damage. MCH displayed superior O2 ·- quenching abilities compared to curcumin and vitamin C. In vitro stability of MCH was also improved compared with curcumin. Exposure of PC12 cells to 150 µM H2O2 caused a decrease of antioxidant enzyme activities, glutathione (GSH) loss, an increase in malondialdehyde (MDA) level, and leakage of lactate dehydrogenase (LDH), cell apoptosis and reduction in cell viability. Pretreatment of the cells with MCH at 0.63-5.00 µM before H2O2 exposure significantly attenuated those changes in a dose-dependent manner. MCH enhanced cellular expression of transcription factor NF-E2-related factor 2 (Nrf2) at the transcriptional level. Moreover, MCH could mitigate intracellular accumulation of reactive oxygen species (ROS), the loss of mitochondrial membrane potential (MMP), and the increase of cleaved caspase-3 activity induced by H2O2. These results show that MCH protects PC12 cells from H2O2 injury by modulating endogenous antioxidant enzymes, scavenging ROS, activating the Nrf2 cytoprotective pathway and prevention of apoptosis. [ABSTRACT FROM AUTHOR]

When exposed to visible light, 2,5-di- tert-butyl-6-hydroxy-6-methylcyclohexa-2,4-dienone undergoes rearrangements in several steps. The first, photochemical step involves contraction of the six-membered ring to a five-membered cyclic ketol. Its subsequent rearrangements follow a number of parallel pathways. The main pathway involves the formation of an unstable intermediate bicyclo[3.1.0]hexenone derivative, whose further transformation leads to 4-acetylcyclopentenone via opening of the three-membered ring in a deaerated solution or to a bicyclic peroxide in the presence of air. In addition, a parallel bimolecular reaction of the five-membered ketol yields sterically hindered 2-acetylcyclopentenone. [ABSTRACT FROM AUTHOR]

Highlights: [•] We investigated a putative MCHergic modulation on the median raphe nucleus (MnR). [•] Behavioral changes induced by MCH intra-MnR were determined. [•] A large density of MCHergic fibers was detected in MnR. [•] MCH directly microinjected into MnR induced a depressive-like effect. [•] MnR participates in the MCHergic control of affective-related behavioral responses. [ABSTRACT FROM AUTHOR]

Abstract: Terpinolene's (1-methyl-4-(propan-2-ylidene)cyclohexene) reaction with ozone or the nitrate radical was investigated using a denuder/filter apparatus in order to characterize gas-phase and particulate reaction products. Identification of the reaction products (i.e., aldehydes, ketones, dicarbonyls and carboxylic acids) was made using two derivatization methods; O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) to derivatize the carbonyl products or 3-Ethyl-1-[3-(dimethylamino)propyl]carbodiimide hydrochloride (EDC) and 2,2,2-trifluoroethylamine hydrochloride (TFEA) to derivatize the carboxylic acid products. Proposed carbonyl products for ozonolysis of terpinolene are: 4-methylcyclohex-3-en-1-one, 2-hydroxy-4-methylcyclohex-3-en-1-one, glyoxal, methyl glyoxal, 3-oxobutanal, and 6-oxo-3-(propan-2-ylidene)heptanal. Proposed carbonyl products for nitrate radical reaction of terpinolene are: 2-hydroxy-4-methylcyclohex-3-en-1-one, glyoxal, methyl glyoxal, and 4-oxopentanal. No carboxylic acid products were detected with either oxidizing reactant. [Copyright &y& Elsevier]

A facile and simple route for the direct preparation of substituted 3-methylcyclohex-2-enone via Aldol-Robinson cascade reaction of aldehydes and acetones catalyzed by the new catalytic system of L-lysine/imidazole in n-heptane with 0.5% water was reported. A variety of substrates can participate in the process efficiently. The merits of this method included inexpensive and easily available starting materials and catalyst, the good yield of products and the straightforward work-up. [ABSTRACT FROM AUTHOR]

Rationale: Selective rapid eye movement sleep (REMS) deprivation using the platform-on-water ('flower pot') method causes sleep rebound with increased REMS, decreased REMS latency, and activation of the melanin-concentrating hormone (MCH) expressing neurons in the hypothalamus. MCH is implicated in the pathomechanism of depression regarding its influence on mood, feeding behavior, and REMS. Objectives: We investigated the effects of the most selective serotonin reuptake inhibitor escitalopram on sleep rebound following REMS deprivation and, in parallel, on the activation of MCH-containing neurons. Methods: Escitalopram or vehicle (10 mg/kg, intraperitoneally) was administered to REMS-deprived (72 h) or home cage male Wistar rats. During the 3-h-long 'rebound sleep', electroencephalography was recorded, followed by an MCH/Fos double immunohistochemistry. Results: During REMS rebound, the time spent in REMS and the number of MCH/Fos double-labeled neurons in the lateral hypothalamus increased markedly, and REMS latency showed a significant decrease. All these effects of REMS deprivation were significantly attenuated by escitalopram treatment. Besides the REMS-suppressing effects, escitalopram caused an increase in amount of and decrease in latency of slow wave sleep during the rebound. Conclusions: These results show that despite the high REMS pressure caused by REMS deprivation procedure, escitalopram has the ability to suppress REMS rebound, as well as to diminish the activation of MCH-containing neurons, in parallel. Escitalopram caused a shift from REMS to slow wave sleep during the rebound. Furthermore, these data point to the potential connection between the serotonergic system and MCH in sleep regulation, which can be relevant in depression and in other mood disorders. [ABSTRACT FROM AUTHOR]

Widely tunable terahertz (THz) waves were successfully generated from 0.5 to 10 THz via difference frequency generation (DFG) in a configurationally locked polyene 2-[3-(4-hydroxystyryl)-5,5-dimethylcyclohex-2-enylidene] malononitrile (OH1) crystal. Potassium titanium oxide phosphate optical parametric oscillator pumped by nanosecond Q-switched Nd:YAG laser was used to generate two waves, which were then used to irradiate OH1 crystal. The maximum energy of the generated THz wave was about 461 pJ/pulse. We investigated the dependency of generated THz energy to the excitation pump power density and OH1 crystal thickness. In addition, we compared the THz energy generated by OH1 crystal to 4- N, N-dimethylamino-4′- N′-methyl-4-stilbazolium tosylate (DAST) crystal using DFG, and we achieved 560 times higher energy using OH1 crystal than DAST crystal at around 1.1 THz. [ABSTRACT FROM AUTHOR]

Abstract: The 5-(2-phenylhydrazono)-3,3-dimethylcyclohexanone (PHDMC) is synthesized by reacting 5,5-dimethylcyclohexane-1,3-dione with 2-phenylhydrazine. Synthesized PHDMC is polycrystalline with monoclinic space group, P21/a. Miller’s indices values for each diffraction peak in the X-ray diffraction spectrum are calculated. Thin films of PHDMC with different thickness values (0.83–1.247μm) are prepared by thermal evaporation technique and they exhibit amorphous structure. Different vibrational modes, observed in infrared spectra of the powder and thin films, were assigned to the molecular bonding structure of PHDMC compound. The optical properties of PHDMC thin films are investigated by measuring the optical transmittance and reflectance at the normal incidence of the light in the spectral range 200–2500nm. The refractive and absorption indices of the films are found to be independent of the film thickness range mentioned above. The refractive index is analyzed and the dispersion parameters are extracted. Analysis of the absorption coefficient spectra showed that the films have two major indirect allowed electronic transitions; the corresponding optical band gaps are estimated as 2.1 and 3.2eV in the framework of electronic band-to-band transition theory. The direct current electrical conductivity measurements showed the semiconductor property of the films. [Copyright &y& Elsevier]

ABSTRACT Background and objective: Spirometry is insensitive to small airway abnormalities in asthma. Our objective was to evaluate regional lung structure and function using hyperpolarized 3He magnetic resonance imaging (MRI) before, during and after a methacholine challenge (MCh). Methods: Twenty-five asthmatics (mean age = 34 ± 11 years) and eight healthy volunteers (HV) (mean age = 33 ± 11 years) underwent spirometry, plethysmography and hyperpolarized 3He MRI prior to a MCh. MRI was repeated following the MCh and again 25 min after salbutamol administration. 3He MRI gas distribution was quantified using semiautomated segmentation of the ventilation defect percent (VDP). Tissue microstructure was measured using the 3He apparent diffusion coefficient (ADC). Analysis of variance with repeated measures was used to evaluate changes at each time point as well as to determine interactions between regions of interest (ROI) and subject group. Pearson's correlations were performed to evaluate associations between 3He MRI measurements and established clinical measures. Results: In asthmatics, but not HV, whole-lung ADC was increased post-MCh ( P < 0.01). In asthmatics only, ADC was increased post-MCh in posterior ROI ( P < 0.01) and all ROI in the superior-inferior direction ( P < 0.01). VDP was increased in posterior and inferior ROI ( P < 0.001). There was a correlation between VDP and specific airway resistance ( r = 0.74, P < 0.0001), dyspnoea score ( r = 0.66, P < 0.01) and fractional exhaled nitric oxide ( r = 0.45, P < 0.05). Conclusions: We evaluated the regional pulmonary response to methacholine and salbutamol using 3He MRI and showed heterogeneous VDP and ADC consistent with bronchoconstriction and gas trapping, respectively, post-MCh. These regional alterations resolved post-salbutamol. [ABSTRACT FROM AUTHOR]

Single pulse shock tube studies of the thermal dehydrochlorination reactions (chlorocyclopentane → cyclopentene + HCl) and (chlorocyclohexane → cyclohexene + HCl) at temperatures of 843-1021 K and pressures of 1.4-2.4 bar have been carried out using the comparative rate technique. Rate constants have been measured relative to (2-chloropropane → propene + HCl) and the decyclization reactions of cyclohexene, 4-methylcyclohexene, and 4-vinylcyclohexene. Absolute rate constants have been derived using k(cyclohexene → ethene + butadiene) = 1.4 × 1015 exp(−33,500/ T) s−1. These data provide a self-consistent temperature scale of use in the comparison of chemical systems studied with different temperature standards. A combined analysis of the present results with the literature data from lower temperature static studies leads to k(2-chloropropane) = 10(13.98±0.08) exp(−26, 225 ± 130) K/ T) s−1; 590-1020 K; 1-3 bar, k(chlorocylopentane) = 10(13.65 ± 0.10) exp(−24,570 ± 160) K/T) s−1; 590-1020 K; 1-3 bar, k(chlorocylohexane) = 10(14.33 ± 0.10) exp(−25,950 ± 180) K/T) s−1; 590-1020 K; 1-3 bar, Including systematic uncertainties, expanded standard uncertainties are estimated to be about 15% near 600 K rising to about 25% at 1000 K. At 2 bar and 1000 K, the reactions are only slightly under their high-pressure limits, but falloff effects rapidly become significant at higher temperatures. On the basis of computational studies and Rice-Ramsperger-Kassel-Marcus (RRKM)/Master Equation modeling of these and reference dehydrochlorination reactions, reported in more detail in an accompanying article, the following high-pressure limits have been derived: k∞ (2-chloropropane) = 5.74 × 109T1.37 exp(−25,680/T) s−1; 600-1600 K, k∞ (chlorocylopentane) = 7.65 × 107T1.75 exp(−23,320/T) s−1; 600-1600 K, k∞ (chlorocylohexane) = 8.25 × 109T1.34 exp(−25,010/T) s−1; 600-1600 K, © 2011 Wiley Periodicals, Inc.* Int J Chem Kinet 44: 351-368, 2012 [ABSTRACT FROM AUTHOR]

Abstract: Major histocompatibility complex (MHC) class I and class II are crucial for the function of the human adaptive immune system. A member of the NLR (nucleotide-binding domain, leucine-rich repeat) protein family, NLRC5, has recently been identified as a transcriptional regulator of MHC class I and related genes. While a ‘master regulator’ of MHC class II genes, CIITA, has long been known, NLRC5 specifically associates with and transactivates the proximal promoters of MHC class I genes. In this study, we analyzed the molecular requirements of NLRC5 nuclear import and transactivation activity. We show that NLRC5-mediated MHC class I gene induction requires an intact nuclear localization signal and nuclear distribution of NLRC5. In addition, we find that the nucleotide-binding domain (NBD) of NLRC5 is critical not only for nuclear translocation but also for the transactivation of MHC class I genes. Changing the cellular localization of NLRC5 is likely to immediately impact MHC class I expression as well as MHC class I-mediated antigen presentation. NLRC5 may thus provide a promising target for the modulation of MHC class I antigen presentation, especially in the setting of transplant medicine. [Copyright &y& Elsevier]

The synthesis of 1 H-pyrazolo[3,4- c]isoquinolin-1-ones was carried out by reacting 3-aryl(heteryl)-2,4-diacetyl-5-hydroxy-5-methylcyclohexanones with 3-amino-1-phenyl-1 H-pyrazol-5(4 H)-one. The structure of the 7-acetyl-2,4,6,7,8,9-hexahydro-8-hydroxy-5,8-dimethyl-2-phenyl-6-(fur-2-yl)-1 H-pyrazolo[3,4- c]isoquinolin-1-one obtained was proved by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Abstract: Ring-opening reactions of decalin and MCH were studied over monofunctional acid (WO3/Al2O3) and metal (Ir/Al2O3) catalysts containing, respectively, up to 5.3 at. W/nm2 and 1.8wt% Ir. The catalysts were characterized by X-ray diffraction, Raman spectroscopy, low-temperature CO adsorption followed by infrared spectroscopy, and H2 chemisorption. A reaction network was proposed for both molecules and used to determine the kinetic parameters. Kinetic modeling allowed relating characterization results and catalytic performance. For WO3/Al2O3 catalysts, ring contraction precedes ring opening of both molecules. The evolution of ring contraction activity was consistent with the development of relatively strong Brønsted acid sites. Ring opening occurs according to a classic acid mechanism. For Ir/Al2O3 catalysts, only direct ring opening was observed. Ring opening proceeds mostly via dicarbene mechanism. Analysis of products indicated that monofunctional metal catalysts are better suited than acid solids for upgrading LCO. [Copyright &y& Elsevier]

Electrochemical investigation of 4(6)-dihalomethyl-4(6)-methylcyclohexa-2,5(2,4)-dien-1-ones using cyclic voltammetry (CVA) and rotating disc electrode (RDE) methods has been performed. The reductive dehalogenation of cyclohexa-2,5(2,4)-dien-1-ones having a dihalomethyl substituent at the tertiary carbon atom was shown to proceed as a two-electron reductive elimination of the geminal halogen atoms with the intermediate formation of carbene and subsequent rearrangement of cyclohexadienone with the ring expansion to the corresponding 4- or 2-methylcyclohepta-2,4,6-trien-1-one. [ABSTRACT FROM AUTHOR]

Enantiomerically pure 1,4-dihydropyridines are prepared taking advantage of magnesium nitride as a useful and convenient source of 'solid ammonia'. The products possess various substituents at carbons 3, 4 and 5 of the dihydropyridine moiety. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, hydrogen and methanol production rates are simultaneously investigated through the process intensification (PI) concept. PI is a strategy for reduction of emissions as well as consumption of energy and materials. Endothermic dehydrogenation of methylcyclohexane is supposed to occur in the shell side of conventional methanol synthesis reactor. The reactor is consisted of two thermally coupled concentric tubular reactors. The rate of the dehydrogenation reaction can be adjusted according to the generated heat in the exothermic side. This is like a smart cooler. By using this new configuration, the equilibrium condition in the methanol synthesis (at the last part of the reactor) can be controlled in order to enhance the production rate. The effect of various operating conditions is investigated through this article. The results of simulation are compared with the corresponded outcome of the conventional methanol reactor. Innovations in reactor configuration, which somehow could be the heart of chemical processes, are often preferred to be the starting point of revamping a process. An investigation in relation to the environmental aspects, commercial viability and economic feasibility of the proposed configuration is necessary in order to consider commercialization of the process. [Copyright &y& Elsevier]

Abstract: Absolute cross sections for electron ionization of methylcyclohexane (MCH, C7H14) are measured as a function of the electron energy in a range of 10–200eV. The electron ionization of MCH produces the parent ion C7H14 + ment ions C6H11 + and C4H7 + as the predominant product ions at most of the electron energies studied. Reactions between selected hydrocarbon ions with the neutral MCH molecule, mainly via hydride transfer, charge transfer and H2 − transfer mechanisms, are studied. Absolute rate constants are reported, and the correlations between the reactivities and the thermochemical data of the reactions are discussed. The Binary-Encounter-Bethe method is applied to MCH to provide a theoretical comparison to the sum of the measured ionization cross sections. [Copyright &y& Elsevier]

9-Methyl-3,5-dioxo-4-azatricyclo[5.2.2.02,6]undec-8-ene-1,8-diyl diacetate was synthesized from 2-methylcyclohexane-1,3-dione and 1H-pyrrole-2,5-dione. The title compound was characterized by 1H NMR, 13C NMR, elemental analysis and MS. [ABSTRACT FROM AUTHOR]

Abstract: Interactions between the T cell receptor and cognate peptide–MHC are crucial initiating events in the adaptive immune response. These binding events are highly specific yet occur with micromolar affinity. Even weaker interactions between TCR and self-pMHC complexes play critical regulatory roles in T cell development, maintenance and coagonist activity. Due to their low-affinity, the kinetics and thermodynamics of such weak interactions are difficult to study. In this work, we used M15, a high-affinity TCR engineered from the 3.L2 TCR system, to study the binding properties, thermodynamics, and specificity of two altered peptide ligands (APLs). Our affinity measurements of the high-affinity TCR support the view that the wild type TCR binds these APLs in the millimolar affinity range, and hence very low affinities can still elicit biological functions. Finally, single methylene differences among the APLs gave rise to strikingly different binding thermodynamics. These minor changes in the pMHC antigen were associated with significant and unpredictable changes in both the entropy and enthalpy of the reaction. As the identical TCR was analyzed with several structurally similar ligands, the distinct thermodynamic binding profiles provide a mechanistic perspective on how exquisite antigen specificity is achieved by the T cell receptor. [Copyright &y& Elsevier]

This paper addresses the hypothetical relationship of photography and so-called pheromone maps created by an artificial life system that simulates an ant colony and causes its activity to evolve based on the contours of images. Pheromone--used by ants to communicate via the environment--is also simulated, and from the communication and interaction of the swarm with the environment (an image) there results a kind of drawing made with the simulated pheromone. Since ants are able to detect the edges of the image, the outcome is a sketch that resembles the original image, as with old camera obscura drawings. This text explores the observable traits shared by the photographic process and the swarm's pheromone maps. The theme is discussed in the context of the emergent artificial art research field; recent theoretical advances that link swarm intelligence and cognitive sciences are also addressed. [ABSTRACT FROM AUTHOR]

The article offers information on the synthesis of various 2,8-cyclootadience-1,2-dicarboxylates. It discusses the mechanism of the reactions of enamines with acetylene derivatives especially the factors that affect them, such as the remarkable effect of the organic solvent and the effect of amine moiety on the rate of reaction and formation of products. It investigates the enamine formation reaction of 2-methylcyclohexanone with pyrrolidine or morpholine and with isomeric reactions and the cycloaddition reactions of the morpholine enamine of 2-methylcyclohexaonone.

Objective: Recent studies have shown that the current guidelines suggesting immunologic monitoring to determine response to highly active antiretroviral therapy (HAART) are inadequate. We assessed whether routinely collected clinical markers could improve prediction of concurrent HIV RNA levels. Methods: We included individuals followed within the Johns Hopkins HIV Clinical Cohort who initiated antiretroviral therapy and had concurrent HIV RNA and biomarker measurements ≥4 months after HAART. A two tiered approach to determine whether clinical markers could improve prediction included: 1) identification of predictors of HIV RNA levels >500 copies/ml and 2) construction and validation of a prediction model. Results: Three markers (mean corpuscular hemoglobin [MCH], CD4, and change in percent CD4 from pre-HAART levels) in addition to the change in MCH from pre-HAART levels contained the most predictive information for identifying an HIV RNA >500 copies/ml. However, MCH and change in MCH were the two most predictive followed by CD4 and change in percent CD4. The logistic prediction model in the validation data had an area under the receiver operating characteristic curve of 0.85, and a sensitivity and specificity of 0.74 (95% CI: 0.69-0.79) and 0.89 (95% CI: 0.86-0.91), respectively. Conclusions: Immunologic criteria have been shown to be a poor guideline for identifying individuals with high HIV RNA levels. MCH and change in MCH were the strongest predictors of HIV RNA levels >500. When combined with CD4 and percent CD4 as covariates in a model, a high level of discrimination between those with and without HIV RNA levels >500 was obtained. These data suggest an unexplored relationship between HIV RNA and MCH. [ABSTRACT FROM AUTHOR]

Abstract: S-(+)-carvone (5-isopropenyl-2-methylcyclohex-2-en-1-one) is the primary component in the oil of caraway. Different experimental and theoretical works reveal that there are two possible conformers in which the isopropenyl group can be in equatorial or axial position. For each one, three rotamers were found theoretically, with the equatorial rotamers around 95% of the whole statistical population. In the current work, from a complete assignment of the IR and Raman spectra and the results obtained from the study of the VCD spectrum of the title compound, the three most stable rotamers have been detected experimentally in the liquid phase for the first time. The present work reveals that IR, Raman and VCD are helpful complementary techniques to characterize flexible systems, as terpenes, which present several conformers. [Copyright &y& Elsevier]

Liquid phase Friedel-Crafts acylation of cyclohexene and 1-methylcyclohexene was investigated over zeolites and mesoporous molecular sieves. The effect of the structure and concentration and type of active sites on the conversion and selectivity of cyclohexene and 1-methylcyclohexene was investigated. In addition, the effect of the chain length of acylating agent was studied. Catalytic experiments were carried out at temperature 80 °C and at atmospheric pressure. The highest conversion was reached over zeolite Beta with Si/Al ratio 37.5 (cyclohexene conversion 78.7%, 1-methylcyclohexene conversion 54.1%). It was found that with increasing chain length of the acylating agent cyclohexene as well as 1-methylcyclohexene conversions decrease. No direct relationship between the conversion of cyclohexene or 1-methylcyclohexene and the concentration of Lewis acid sites was found. [ABSTRACT FROM AUTHOR]

5-Aryl-1-methyl-1,2,3,4-tetrahydrobenzo[ a]phenanthridines were synthesized by cascade heterocyclization of the corresponding substituted benzaldehydes with 2-methylcyclohexanone and naphthalen-2-amine in a polar solvent in the presence of hydrochloric acid. [ABSTRACT FROM AUTHOR]

Abstract: We tested methylcyclohexenone (MCH), an anti-aggregation pheromone for the Douglas-fir beetle (Dendroctonus pseudotsugae), for protection of Douglas-fir (Pseudotsuga menziesii) stands by applying MCH-releasing polymer flakes by helicopter twice during summer 2006 to five 4.05-ha plots in the State of Washington, USA. Five similar plots served as untreated controls. We assessed D. pseudotsugae flight into study plots using baited pheromone traps, and tallied D. pseudotsugae attack rates on all P. menziesii trees in 2005 and 2006. We also measured stand basal area and incorporated that as an explanatory variable in the analysis. Significantly fewer D. pseudotsugae were trapped in treated plots than in control plots, and significantly fewer P. menziesii trees were attacked in treated plots than in control plots. The attack rate in untreated stands was nearly 10 times that of treated plots, and stands with higher basal area were significantly more likely to be attacked by D. pseudotsugae than were stands of lower basal area. Attack rates in 2006 and 2005 were significantly correlated, regardless of treatment. [Copyright &y& Elsevier]

To assess some simple blood parameters at birth that can be used as a basis to suspect a-thalassemia minor (ATM), a prospective study involving 202 consecutive neonates with MCV of less than 95 fl or less were checked for Hb Barts by HPLC. The group was divided into two, one with an MCV of 90-95 (89 cases) and the other with an MCV below 90 (113 cases). For control, 104 consecutive neonates with an MCV > 95 fl were similarly checked. It has been confi rmed that an MCV that is below 90 fl , especially with and MCH of <30 pg is a strong indicator of the presence of ATM (109/113). On the other hand, MCV of 90 or more, especially with an MCH of 30 or more is a strong negative indicator for ATM (70/89). Firm diagnosis of ATM at birth can thus be secured in majority of neonates. [ABSTRACT FROM AUTHOR]

The biotransformation of 2-methylcyclohexanone ( 1) using 16 fungal strains and some mushroom cultures was investigated. Fusarium sp. was one of the effective biocatalysts for oxidoreduction of 2-methylcyclohexanone ( 1). cis-2-Methylcyclohexanol ( 2a) was isomerized to trans-2-methylcyclohexanol ( 2b) by Fusarium sp. In addition, the corresponding lactones 3 was obtained by Baeyer-Villiger oxidation using Fusarium sp. AP-2 (46%, 94% ee). [ABSTRACT FROM AUTHOR]

Abstract: This study aimed to determine whether the route of administration of methacholine (MCh) influenced the pattern of airway hyper-responsiveness (AHR) in mice. BALB/c mice were inoculated with a 50-μL volume containing 104.5-pfu Influenza virus A/Mem/1/71(H3N1) or media. MCh responsiveness in vivo [inhaled (0.01–30mg/mL), i.v. MCh (6–48μg/min/kg)] and in vitro were measured at day 4 post-infection (D4) during acute lower respiratory infection (LRI) and following resolution of infection at day 20 (D20) using a low-frequency, forced oscillation technique. Inflammation was assessed in bronchoalveolar lavage fluid. Infected mice had pulmonary inflammation and heightened responsiveness to both inhaled (p <0.03) and intravenous (p <0.02) MCh on D4, but not on D20. In vitro responsiveness was not altered at either time point. Influenza A LRI results in AHR during acute infection associated with a marked inflammatory response and increased permeability of the alveolar–capillary barrier. These data suggest that intrinsic muscle properties are not altered but MCh has greater access to airway smooth muscle during acute infection. [Copyright &y& Elsevier]

The overall objective of this study was to assess the effects of 1-methylcyclopropene (1-MCP) on the quality of yellow “Shiro” plums. During 2 years of study, plums were harvested from commercial orchards and exposed to 1 µL/L of 1-MCP for 24 h at 0C. Following treatment, the fruit were held at 0C for 0, 2 or 4 weeks and then evaluated for quality during a 2-week ripening period at 22C. In general, plums treated with 1-MCP were firmer, had higher soluble solids concentration (SSC) and retained more green color than non-treated fruits. The effect of 1-MCP on firmness was greater in plums from earlier harvests and in those stored for 4 weeks at 0C. 1-MCP treatment also reduced CO2 production, ethylene and hydrophobic total volatiles in “Shiro” plums but these effects were reduced or lost with longer storage time. PRACTICAL APPLICATIONS The use of 1-MCP could be beneficial for extending the marketing window of “Shiro” plums, since firmness retention is improved and the color change from green to yellow is delayed. The limited effect of 1-MCP on CO2 and ethylene production may be advantageous in that these are delayed and not completely inhibited. In climacteric fruits such as plum, the limited period of 1-MCP effectiveness could be a benefit when successful 1-MCP application requires a delay, rather than irretrievable inhibition of the ripening processes, which reduces marketability. [ABSTRACT FROM AUTHOR]

The isomerization of cyclohexylium to methylcyclopentylium is a model for a key step required in sterol and triterpene biosynthesis and is important in catalytic processes associated with ring-opening reactions in upgrading petroleum fractions. Using high-level, correlated wave function techniques based on QCISD, the mechanism for this isomerization was found to be very different from that first proposed more than 35 years ago. On the basis of our mechanism, a first-order rate constant expression was derived and used with complete basis set-extrapolated QCISD(T) energies to obtain Ea6.9 kcal/mol and A1011.18s-1, in excellent agreement with values of 7.4 ± 1 kcal/mol and A1012 ± 1.3s-1measured in the gas phase. The B3LYP and MP2 methods, two commonly used computational approaches, were found to predict incor-rect mechanisms and, in some cases, poor kinetic parameters. The PBE method, however, produced a reac tion profile and kinetic parameters in reasonable agreement with those obtained with the complete basis set-extrapolated QCISD(T) method. [ABSTRACT FROM AUTHOR]

Abstract: The catalytic transformation of methylcyclohexane (mcha), as representative of the reactions taking place during catalytic cracking, was carried out on a H-EU-1 zeolite under the following conditions: 623 K, atmospheric pressure, ratio equal to 9, contact time (taken as the reciprocal of the weight hourly space velocity) between 0.016 and 0.3 h. Whatever the contact time and time-on-stream, cracking was the main reaction, like on other 10-MR zeolites, but significant amounts of isomers and aromatics were produced. Moreover, cracking led predominantly to branched products, in contradiction with the shape selectivity expected from the narrow pore openings of this 10-MR zeolite. All this could be explained by a very important catalytic contribution of the protonic sites located at the pore mouths. Additional experiments using bulky basic compounds (γ-collidine) confirmed this hypothesis and allowed estimation of the selectivity of these acid sites. [Copyright &y& Elsevier]

Abstract: This paper describes the lead optimization of a new series of potent, selective, orally bioavailable, brain-penetrant MCH-1 receptor antagonists. A major focus of the work was to achieve a selectivity profile appropriate for in vivo efficacy studies and safety. [Copyright &y& Elsevier]

Abstract: To address the hERG liability of MCHR1 antagonists such as 1 and 2, new analogs such as 4 and 5 that incorporated a polar heteroaryl group were designed and synthesized. Biological evaluation confirmed that these new analogs retained MCH R1 activity with greatly attenuated hERG liabilities as indicated in the Rb efflux assay. [Copyright &y& Elsevier]

An efficient first synthesis of the sesquiterpene ar-macrocarpene, an irregular sesquiterpene isolated from Cupressus macrocarpa foliage, starting from 3-methylcyclohexenone has been described, which confirmed the structures of macrocarpenes. [ABSTRACT FROM AUTHOR]

Abstract: N-(tert-butoxycarbonyl)-3-(benzoxazol-5-yl)alanine methyl ester derivatives substituted in position 2 by heterocyclic group were synthesized and their photophysical properties in methanol, acetonitrile and methylcyclohexane were studied by means of absorption and fluorescence spectroscopies. The positions of their emission bands depend on the solvent polarity and are shifted to longer wavelengths in more polar solvents as a result of a charge transfer from a substituent to the benzoxazole moiety. High molar absorption coefficient values and fluorescence quantum yields are characteristic for most of the compounds studied making them efficient fluorescent probes. Moreover, the presence of additional heteroatom in the substituent enables those compounds to act as chemosensors for metal ions or protons. [Copyright &y& Elsevier]

Abstract: We have identified a novel series of potent MCH-R1 antagonists based on l-arginine. As predicted by computational methods, there was an activity dependence on the π-electronic character of the aromatic systems corresponding to the amino-terminus of these molecules. These results have enhanced our understanding of the MCH-R1 receptor and the potential for a predictive homology model. [Copyright &y& Elsevier]

Abstract: A direct correlation between hERG binding and QTc prolongation was established for a series of aminomethyl tetrahydronaphthalene ketopiperazine MCH-R1 antagonists. Compounds within this class with greater selectivity over hERG were developed. Compound 4h proved to have the best profile, with MCH-R1 K i =16nm and hERG IC50 =25μM. [Copyright &y& Elsevier]

Abstract: In this paper, a transient pseudo-homogeneous model was developed with the objective of describing the activity, product distribution and deactivation with time on stream for the methylcyclohexane transformation over H-USY at 350°C. The reaction scheme details the reactant, cyclopentane ring isomers, alkenes, alkanes, aromatics and coke. The existence of adsorbed species is neglected, exception made for coke molecules that remain trapped inside the catalyst, being responsible by the catalyst deactivation. The effect of a model basic nitrogen molecule (quinoline) in the feed is also described by the model; both its roles as a poison and as coke precursor are accounted for. The fitting was done using data determined experimentally at 350°C for 1/WHSV (weight hourly space velocity) values of 12 and 4min, as a function of time on stream. The model fits extremely well the activity, deactivation and product distribution, coke included. [Copyright &y& Elsevier]

3- and 4-Methylcyclohexanone have been isolated exclusively as their energetically disfavoured axial conformers in the host-guest complexes formed upon recrystallization of the novel optically pure host compound, (+)-(2R,3R)-1,1,4,4-tetraphenylbutane-1,2,3,4-tetraol (TETROL), from these cycloalkanones. [ABSTRACT FROM AUTHOR]