Numerical simulation of emulsified fuel spray combustion with puffing and micro-explosion

The purpose of this study was to develop numerical simulation of spray combustion of emulsified fuel with considering puffing and micro-explosion. First, a mathematical model for puffing was proposed. In the proposed puffing model, the rate of mass change of a droplet during puffing was expressed by the evaporation rate of dispersed water and the mass change rate due to fine droplets spouted from the droplet surface. The mass change rate due to fine droplets was related to the evaporation rate of the dispersed water and each liquid content. This model had only one experimental parameter. The essential feature of this model was that it was simple to apply to numerical simulation of spray combustion. First, the validity of the proposed puffing model was investigated with the experimental results for a single droplet. The calculated results for a single droplet with the experimental parameter varying from 5.0 to 10 were in good agreement with the experimental results. Moreover, numerical simulation of spray combustion of emulsified fuel was carried out. The occurrence of puffing and micro-explosion was determined by the inner droplet temperature. When micro-explosion occurred, a droplet changed to vapor rapidly. When the proposed puffing model was used in numerical simulation of spray combustion, the experimental parameter in the puffing model was determined for each droplet by random numbers within the range 5.0-10. The calculated results of spray combustion of emulsified fuel without considering puffing or micro-explosions were different from the experimental results even where combustion reactions were almost terminated. Meanwhile, the calculated results when considering puffing and micro-explosions were in good agreement with experimental results at the same location.     

Dietary protein modulates the effect of CLA on lipid metabolism in rats

The effect of the interaction of CLA and type of dietary protein on lipid metabolism was studied in male rats by feeding diets containing casein (CAS) or soy protein (SOY) as dietary protein and either linoleic acid (LA, a control FA) or graded levels of CLA at 0,0.1, 0.5, and 1.0% for 28 d. CLA reduced the weight of perirenal adipose tissue in a dose-dependent manner, but the magnitude of the reduction was greater when rats were fed SOY. Feeding SOY resulted in a significant reduction of the concentrations of serum total and HDL cholesterol, TG, glucose, and insulin irrespective of dietary CLA. The concentration of serum leptin tended to be lower on the SOY diet free of CLA than in the corresponding CAS diet, but it fell with an increasing dietary level of CLA in the CAS groups. In contrast, serum leptin tended to increase when CLA was added to SOY diets. The concentration of serum adiponectin was higher in the CAS than in the SOY groups, and it tended to increase in response to dietary CLA levels in the CAS-fed rats, whereas CLA showed no effect in SOY-fed rats. The activity of liver mitochondrial carnitine palmitoyltransferase was higher in the SOY than in the CAS groups, but it tended to increase with an increasing dietary level of CLA in both protein groups. Although the body fat-reducing activity of CLA was more effective when the protein source was SOY, rats fed CAS appeared to be more susceptible to CLA than in those fed SOY with respect to cytokines examined. These results suggest that the type of dietary protein may modify the antiobesity activity of CLA.     

The promoting effect of halogen ions on selective hydrogenation of (E)-2-butenal to (E)-2-buten-1-ol over alumina-supported cobalt catalyst

The promoting effects of halogen ions (Cl⁻, Br⁻, I⁻) on catalytic activity and selectivity in the hydrogenation of (E)-2-butenal to form (E)-2-buten-1-ol were investigated using alumina-supported cobalt catalyst in a liquid phase. The addition of Cl⁻ or Br⁻ to the reaction media greatly promoted the formation of (E)-2-buten-1-ol and simultaneously suppressed the formation of butanal, whereas the addition of I⁻ prevented CC bond hydrogenation. The promoting effects increased with increasing electronegativity of the halogen atoms. The rate ratio of CO bond hydrogenation to CC bond hydrogenation was increased eightfold when Cl⁻ was used under optimum conditions.     

Effects of electrochemical-deposition method and microstructure on the capacitive characteristics of nano-sized manganese oxide

The amorphous nano-structured manganese oxide was electrochemically deposited onto a stainless-steel electrode. The structure and surface morphology of the obtained manganese oxide were studied by means of X-ray diffraction analysis and scanning electron microscopy. The capacitive characteristics of the manganese oxide electrodes were investigated by means of cyclic voltammetry and constant current charge-discharge cycling. The morphological and capacitive characteristics of the hydrous manganese oxide was found to be strongly influenced by the electrochemical deposition conditions. The highest specific capacitance value of ca. 410 F g⁻¹ and the specific power of ca. 54 kW kg⁻¹ were obtained at 400 mV s⁻¹ sweep rate of potentiodynamic deposition condition. The cyclic-life data showed that the specific capacitance was highly stable up to 10,000 cycles examined. This suggests the excellent cyclic stability of the obtained amorphous hydrous manganese oxide for supercapacitor application.     

Synthesis of a squash-type protease inhibitor by gene engineering and effects of replacements of conserved hydrophobic amino acid residues on its inhibitory activity

Cucurbita maxima trypsin inhibitor I (CMTI-I), a member of thesquash-type protease inhibitor family, is composed of 29 aminoacids and shows strong inhibition of trypsin by its compactstructure. To study the structure–function relationshipof this inhibitor using protein engineering methods, we constructedan expression system for CMTI-I as a fused protein with porcineadenylate kinase (ADK). A Met residue was introduced into thejunction of ADK and CMTI-I to cleave the fusion protein withCNBr, whereas a Met at position 8 of authentic CMTI-I was replacedby Leu. Escherichia coli JM109 transformed with the constructedplasmid expressed the fused protein as an inclusion body. Aftercleavage of the expressed protein with CNBr, fully reduced speciesof CMTI-I were purified by reversed-phase HPLC and then oxidizedwith air by shaking. For efficient refolding of CMTI-I, we used50 mM NH₄HCO₃ (pH 7.8) containing 0.1% PEG 6000 at higher proteinconcentration. Strong inhibitory activity toward trypsin wasdetected only in the first of three HPLC peaks. The inhibitorconstant of CMTI-I thus obtained, in which Met8 was replacedby Leu, was 1.4x10-¹⁰ M. The effect of replacement of Met withLeu at position 8 was shown to be small by comparison of theinhibitor constant of authentic CMTI-III bearing Lys at position9 (8.9x10-¹¹ M) with that of its mutant bearing Leu at position8 and Lys at position 9 (1.8x10-¹⁰ M). To investigate the roleof the well conserved hydrophobic residues of CMTI-I in itsinteraction with trypsin, CMTI-I mutants in which one or allof the four hydrophobic residues were replaced by Ala were prepared.The inhibitor constants of these mutants indicated that thosewith single replacements were 5–40 times less effectiveas trypsin inhibitors and that the quadruple mutant was –450times less effective, suggesting that the hydrophobic residuesin CMTI-I contribute to its tight binding with trypsin. However,each mutant was not converted to a temporary inhibitor.     

Tumor-Specificity,Neurotoxicity, and Possible Involvement of the Nuclear Receptor Response Pathway of 4,6,8-Trimethyl Azulene Amide Derivatives

Background: Very few papers covering the anticancer activity of azulenes have been reported, as compared with those of antibacterial and anti-inflammatory activity. This led us to investigate the antitumor potential of fifteen 4,6,8-trimethyl azulene amide derivatives against oral malignant cells. Methods: 4,6,8-Trimethyl azulene amide derivatives were newly synthesized. Anticancer activity was evaluated by tumor-specificity against four human oral squamous cell carcinoma (OSCC) cell lines over three normal oral cells. Neurotoxicity was evaluated by cytotoxicity against three neuronal cell lines over normal oral cells. Apoptosis induction was evaluated by Western blot and cell cycle analyses. Results: Among fifteen derivatives, compounds 7, 9, and 15 showed the highest anticancer activity, and relatively lower neurotoxicity than doxorubicin, 5-fluorouracil (5-FU), and melphalan. They induced the accumulation of a comparable amount of a subG₁ population, but slightly lower extent of caspase activation, as compared with actinomycin D, used as an apoptosis inducer. The quantitative structure–activity relationship analysis suggests the significant correlation of tumor-specificity with a 3D shape of molecules, and possible involvement of inflammation and hormone receptor response pathways. Conclusions: Compounds 7 and 15 can be potential candidates of a lead compound for developing novel anticancer drugs.     

Expression and Function of Nicotinic Acetylcholine Receptors in Induced Regulatory T Cells

A contribution of the cholinergic system to immune cell function has been suggested, though the role of nicotine and its receptors in T cells, especially regulatory T (Treg) cells, is unclear. We herein investigated the expression and function of nicotinic acetylcholine receptors (nAChRs) in murine-induced Treg (iTreg) cells. Upon differentiation of naive BALB/c T cells into iTreg cells and other T-cell subsets, the effect of nicotine on cytokine production and proliferation of iTreg cells was examined. The expression of nAChRs and its regulatory mechanisms were comparatively analyzed among T-cell subsets. Stimulation-induced transforming growth factor-β1 (TGF-β1) production of iTreg cells was suppressed by nicotine, whereas interleukin (IL)-10 production and proliferation was not affected. α2-, α5-, α9-, and β2-nAChRs were differentially expressed in naive, Th1, Th2, Th9, Th17, and iTreg cells. Among these cell types, the α9-nAChR was particularly upregulated in iTreg cells via its gene promoter, but not through tri-methylation at the 4th lysine residue of the histone H3-dependent mechanisms. We conclude that the immunoregulatory role of Treg cells is modified by the cholinergic system, probably through the characteristic expression of nAChRs.     

Challenging Approach to the Development of Novel Estrogen Receptor Modulators Based on the Chemical Properties of Guaiazulene

Tamoxifen, a therapeutic agent for breast cancer, has been associated with genetic polymorphisms in the metabolism of N,N-dialkylaminoethyl substituent, which plays an important role in the expression of selective estrogen receptor modulator (SERM) activity. To solve this problem, we developed a novel estrogen receptor (ER) modulator, Az-01, on the basis of the aromaticity, dipole moment, and isopropyl group of guaiazulene. Az-01 showed four-fold lower binding affinity for ER than E2 but had similar ER-binding affinity to that of 4-hydroxytamoxifen (4-HOtam). Unlike tamoxifen, Az-01 acted as a partial agonist with very weak estrogenic activity at high concentrations when used alone, and it showed potent anti-estrogenic activity in the presence of E2. The cell proliferation and inhibition activities of Az-01 were specific to ER-expressing MCF-7 cells, and no effect of Az-01 on other cell proliferation signals was observed. These findings are important for the development of new types of SERMs without the N,N-dialkylaminoethyl substituent as a privileged functional group for SERMs.     

Nondestructive high-sensitivity measurement method for activation estimation in accelerator room concrete

This study established a method for easily and quickly estimating the specific activity produced in the concrete walls and floors of accelerator rooms during long-term operation of accelerator,for advanced zoning of activated/non-activated areas in planning the decommissioning of an accelerator.We propose a new,highly sensitive method for nondestructively estimating the specific activity in concrete that can be applied to activation zoning.In this method,instead of direct determination of the specific activities of important long-half-life radionuclides for decommissioning,such as ¹⁵²Eu and ⁶⁰Co,we determine the specific activities of short-half-life radionuclides,²⁴Na and ⁵⁶Mn,in situ to obtain neutron flux.The obtained neutron flux and accelerator operation history yield the specific activities of ¹⁵²Eu and ⁶⁰Co for the advance zoning of activated/non-activated concrete.This method is a powerful long-term prediction tool for concrete activation.     

Partial least squares-based human upper body orientation estimation with combined detection and tracking

This paper deals with the problem of estimating the human upper body orientation. We propose a framework which integrates estimation of the human upper body orientation and the human movements. Our human orientation estimator utilizes a novel approach which hierarchically employs partial least squares-based models of the gradient and texture features, coupled with the random forest classifier. The movement predictions are done by projecting detected persons into 3D coordinates and running an Unscented Kalman Filter-based tracker. The body orientation results are then fused with the movement predictions to build a more robust estimation of the human upper body orientation. We carry out comprehensive experiments and provide comparison results to show the advantages of our system over the other existing methods.