CP Solution Research Articles

Predictive Dirac neutrino spectrum with strong CP solution in SU(5)L × SU(5)R unification

We develop a grand unified theory of matter and forces based on the gauge symmetry SU(5)L × SU(5)R with parity interchanging the two factor groups. Our main motivation for such a construction is to realize a minimal GUT embedding of left-right symmetric models that provide a parity solution to the strong CP problem without the axion. We show how the gauge couplings unify with an intermediate gauge symmetry SU(3)cL × SU(2)2L × U(1)L × SU(5)R, and establish its consistency with proton decay constraints. The model correctly reproduces the observed fermion masses and mixings and leads to naturally light Dirac neutrinos with their Yukawa couplings suppressed by a factor MI/MG, the ratio of the intermediate scale to the GUT scale. We call this mechanism type II-Dirac seesaw. Furthermore, the model predicts δCP = ±(130.4±1.2)° and \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${m}_{{\ u }_{1}}$$\\end{document} = (4.8 – 8.4) meV for the Dirac CP phase and the lightest neutrino mass. We demonstrate how the model solves the strong CP problem via parity symmetry.

Abstract 15020: Activation of Mitochondrial Bk Ca Channels Improves Hemodynamics and Normalizes Phosphoproteomic Changes in Pigs Following Cardioplegic Arrest and Cardiopulmonary Bypass

Introduction: BKCa channels are large conductance Ca++-activated K+ channels, which reside in the inner mitochondrial membrane in cardiomyocytes. We have demonstrated that the BKCa channel activator rottlerin (a.k.a mallotoxin) is cardioprotective during cardioplegic arrest in isolated rodent hearts and in vitro models. Here we used a clinically relevant in vivo swine model of cardioplegic arrest and cardiopulmonary bypass (CP/CPB) with and without rottlerin supplemented CP solution. Mitochondrial signaling alterations were identified by TMT-MS analysis of phosphorylation enriched mitochondrial protein fractions. Methods: Yorkshire swine (50 Kg) of both sexes were subjected to hypothermic CP/CPB (1hour) followed by 1 hour reperfusion. Groups included sham (n = 5), CP/CPB alone (n = 8) and CP/CPB with rottlerin supplemented cardioplegia (1uM) (CP/CPB+R) (n = 7). Mitochondria-enriched fractions were isolated from the left ventricular free wall and subjected to Tandem Mass Tag (TMT) labeling coupled mass spectrometry analysis. Results: CP/CPB pigs had reduced myocardial function indicative of myocardial stunning as shown by decreased LVDevP, and ±dP/dt vs sham (P<.05). BKCa activation significantly restored left ventricular function compared to CP/CPB alone (LVDevP: 74.0 ± 2.8 vs . 52.5±5.0 mmHg, P < .01, +dP/dt: 1482±116 vs . 923±126 mmHg/s, P < .01, and - dP/dt: 1120±116 vs . 629±82 mmHg/s, P < .01). TMT-MS analysis identified 3363 proteins. 410 unique as well as numerous novel phosphorylation sites were significantly regulated in CP/CPB vs sham. Rottlerin treatment generally normalized phosphorylation changes with 175 and 63 different vs CP/CPB and sham, respectively. Enrichment analysis demonstrated significant changes in pathways associated with adrenergic and PKA signaling, calcium handling, mitochondrial dynamics, cristae organization, and oxidative phosphorylation. Conclusions: BKCa-activator supplemented cardioplegia significantly improves myocardial functional recovery following CP/CPB in a clinically relevant large animal model. Furthermore, mitochondrial BKCa-channel activation during cardioplegic arrest normalizes numerous signaling alterations associated with myocardial stunning and cardiac surgery.

Towards automated deduction in cP systems

Inspired by the structure and behaviour of living cells, membrane systems are efficient computing models that can solve NP-complete problems in polynomial time. In this study, we use cP systems to perform automated deduction in equational logic. Using a fixed constant number of generic rewriting rules, our cP solution can perform completion and term reduction efficiently. Given a set of k axioms, the cP system can compute all the critical pairs among the axioms in logarithmic time regardless of k. Even when handling equational theories with n-ary operators, the cP solution’s complexity remains the same. We demonstrate the effectiveness of the approach with a case study. In addition to equational logic, the cP solution can also be used as a prototype to construct deduction cP systems for other logics.

Solving a PSPACE-complete problem with cP systems

There have been a few NP-hard problems solved using cP systems including the travelling salesman problem. However, these problems are typically in NP rather than higher in the polynomial time hierarchy. In this paper, we solve QSAT (also known as TQBF), which is a well-known PSPACE-complete problem. Compared to other extant confluent P systems solutions, our deterministic cP solution only uses a small constant number of custom alphabet symbols (19), a small constant number of rules (10) and a small constant upper limit of membrane nesting depth (6), independent of the problem size.

Formal verification of cP systems using PAT3 and ProB

As a recently proposed membrane computing model, cP systems are capable of solving computational hard and distributed problems. Although several membrane system variants were formally verified in previous research, none of their approaches was applicable to cP systems. To formally verify the safety and liveness properties of cP systems, we solve a famous NP-Complete problem—the subset sum problem—in cP systems and use the PAT3 and ProB model checkers to verify the cP solution. Our cP solution outperforms previous work in time complexity and uses fewer rules. To perform model checking in cP systems, we define several mapping rules from cP notation to formal verification languages CSP# and B. We show that we can use model checkers to effectively detect design errors in cP systems. This work is the first study on formal verification of cP systems, and it showed that cP models can be effectively transformed into model checking problems and verified automatically.

Temperature-dependent in Situ Gel of Clotrimazole: an Experimental Study

The in-situ gel-forming polymeric formulations offer sustained and prolonged action in comparison to conventional drug delivery systems. To formulate and evaluate in situ vaginal gel of clotrimazole. Poloxamer 407 (20%) was slowly added to freezing water (5°C) with constant stirring. The prepared dispersion was refrigerated for 5 h, the different concentrations of polymers were added for preliminary batches. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) were performed for clotrimazole-excipients compatibility study. The final batch was prepared and evaluated for physicochemical parameters, in vitro clotrimazole release, in vitro antifungal activity, and in vivo vaginal tissue irritation test. The compatibility study showed no chemical interaction between clotrimazole and excipients used. The evaluation parameters showed that clotrimazole release was in the range of 8 to 10 h, gelling temperature was in the range of 27-35°C, gelling time was in the range of 28-34 sec, pH was in the range of 4.4-4.8, and viscosities were in the range of 16.4-182.6 cP (solution form) and 10,500-20,756 cP (gel form). The zone of inhibitions for clotrimazole pure drug, the marketed vaginal gel of clotrimazole, and optimized gel formulation was 9.15±0.75 mm, 14.35±1.12 mm, and 18.85±1.56 mm, respectively (p < 0.0001, q = 5.98). An optimized gel formulation was not irritant to vaginal tissue. It was possible to formulate effective in situ vaginal gel for control release action of clotrimazole. IIC.

SCC evaluation of a 2297 Al-Li alloy rolled plate using the slow-strain rate technique

The stress corrosion cracking (SCC) susceptibility of 2297 Al-Li alloy in 1 M NaCl + 0.01 M H2O2 solution (CP solution) and 1 M NaCl + 0.01 M H2O2 + 0.6 M Na2SO4 solution (CPS solution) was investigated by slow-strain rate tests at various strain rates ranging from 10−5 s−1 to 10−7 s−1. The roles of H2O2 and SO42− in the corrosion process were estimated by potentiodynamic polarization and electrochemical impedance spectroscopy. 2297 Al-Li alloy does not fracture ascribed to SCC in CP solution, while it undergoes SCC in CPS solution. In CPS solution, with a decreasing strain rate from 10−5 s−1 to 10−7 s−1, the SCC susceptibility firstly rises and then declines exhibiting a peak value at a strain rate of 10−6 s−1. H2O2 promotes the active dissolution while SO42− lowers the corrosion rate. The SCC fracture is associated with a decline in the dissolution rate of the crack tip by SO42−, which leads to stress concentration. In CPS solution, a reduction in the local dissolution rate of the crack tip leads to stress concentration, resulting in SCC fracture. As the preferred initiation site for a crack, pits also show a noteworthy effect on SCC of 2297 Al-Li alloy.

MICROEMULSION FLOODING MECHANISM FOR OPTIMUM OIL RECOVERY ON CHEMICAL INJECTION

The formation of microemulsion in the injection of surfactant at chemical flooding is crucial for the effectiveness of injection. Microemulsion can be obtained either by mixing the surfactant and oil at the surface or injecting surfactant into the reservoir to form in situ microemulsion. Its translucent homogeneous mixtures of oil and water in the presence of surfactant is believed to displace the remaining oil in the reservoir. Previously, we showed the effect of microemulsion-based surfactant formulation to reduce the interfacial tension (IFT) of oil and water to the ultralow level that suffi cient enough to overcome the capillary pressure in the pore throat and mobilize the residual oil. However, the effectiveness of microemulsion flooding to enhance the oil recovery in the targeted representative core has not been investigated.In this article, the performance of microemulsion-based surfactant formulation to improve the oil recovery in the reservoir condition was investigated in the laboratory scale through the core flooding experiment. Microemulsion-based formulation consist of 2% surfactant A and 0.85% of alkaline sodium carbonate (Na2CO3) were prepared by mixing with synthetic soften brine (SSB) in the presence of various concentration of polymer for improving the mobility control. The viscosity of surfactant-polymer in the presence of alkaline (ASP) and polymer drive that used for chemical injection slug were measured. The tertiary oil recovery experiment was carried out using core flooding apparatus to study the ability of microemulsion-based formulation to recover the oil production. The results showed that polymer at 2200 ppm in the ASP mixtures can generate 12.16 cP solution which is twice higher than the oil viscosity to prevent the fi ngering occurrence. Whereas single polymer drive at 1300 ppm was able to produce 15.15 cP polymer solution due to the absence of alkaline. Core flooding experiment result with design injection of 0.15 PV ASP followed by 1.5 PV polymer showed that the additional oil recovery after waterflood can be obtained as high as 93.41% of remaining oil saturation after waterflood (Sor), or 57.71% of initial oil saturation (Soi). Those results conclude that the microemulsion-based surfactant flooding is the most effective mechanism to achieve the optimum oil recovery in the targeted reservoir.

Abstract 21186: Amelioration of Myocardial Stunning in Pigs Undergoing Cp/cpb With Bkca Channel Activator Supplemented Cardioplegia

Introduction: Activation of mitochondrial large conductance Ca++-activated K+ channels (BKCa) is cardioprotective in cell and rodent isolated heart models of cardioplegic arrest and reperfusion. We previously demonstrated cardioprotection is associated with reduced mitochondrial ROS generation and reorganization of individual electron transport chain complexes into physically associated respiratory supercomplexes (SC) made of ETC complex I/III/IV. In this study, we examined the efficacy of BKCa activation during cardioplegic arrest in a clinically relevant large animal study using pigs subjected to CP/CPB and reperfusion. Methods: 50 kg Yorkshire pigs of either sex were subjected to CP/CPB (hyperkalemic cold blood CP, 1 hr) with or without the BKCa activator mallotoxin (MTX (aka rottlerin)) supplied in the CP solution, followed by reperfusion (1hr). Pigs were instrumented with a PV catheter and IVC occlusions performed at baseline and 30 and 60 mins after weening from bypass. Following surgery, mitochondria were isolated and subjected to Blue-Native PAGE and immunoblotting of ETC complexes to visualize large (~100-1500 kD) mitochondrial SC. Results: Baseline hemodynamics were similar between groups. CP/CPB resulted in significant myocardial stunning in pigs as assessed by LVDP (pre 64.8 mmHg vs post 42.0, P&lt;.05 ), +/-dP/dt (pre 971.4 and -911.8 vs post:588.0 and -541.0, P&lt;.05 ), and end-systolic elastance (Ees: pre 1.28 vs post .63, P=0.1 ) at 60 min reperfusion. However, pigs arrested with CP containing MTX (500 nM) exhibited greatly reduced myocardial stunning with significant improvements in LVDP (pre:65.7 post:67.8 mmHg, P&lt;.01 vs post CP/CPB group) +/- dP/dt (pre:1026.0 and -911.8 vs post:1441.7 and -984.8 mmHg/s, P=.02 and .04 vs CP/CPB) and Ees (pre 1.1, post 1.35, P=.02 vs CP/CPB). LV mitochondria isolated from both groups had two major I/III/IV mitochondrial SC’s of ~1300 (SC1) and ~1000 kD (SC2) as assessed by BN-PAGE and immunoblot. The CP/CPB + MTX group had significant increases in both SC1 (6.0 % vs 18.0%, P=.01) and SC2 (19.7% vs 52.3%, P&lt;.01) expressed as percent of total assembled complex IV. Conclusion: Addition of a BKCa activator to CP solutions ameliorates myocardial stunning in large animals subjected to CP/CPB and reperfusion.

Reprint of “Biomimetic apatite coating on yttria-stabilized tetragonal zirconia utilizing femtosecond laser surface processing”

Yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) have been used in orthopedic and dental implants because of their excellent physicochemical properties. In this study, we developed an apatite coating technique with low thermal effects for Y-TZP ceramics based on a biomimetic process using a supersaturated calcium phosphate solution (CP solution) as a coating medium. To achieve this, we performed femtosecond laser processing with low thermal effects as a surface pre-modification tool for Y-TZP ceramics. By changing the laser scanning mode, we fabricated two different submicro-/micro-structures on the Y-TZP sample. Both laser-treated samples showed increased water wettability due to ablation plasma and partly formed an apatite layer on their surfaces in the CP solution within 7 days. To further enhance the apatite-forming ability, we applied an alternate dipping process to the laser-treated sample in order to precoat the sample with apatite precursors. The laser-treated and precursor-precoated sample successfully formed an apatite layer on the entire surface in the CP solution within a shorter time period (24 h). The thus-coated apatite layer adhered to the sample so strongly that the layer remained on the sample even after the tape-detaching test. This strong adhesion may be attributed to the mechanical interlocking effects due to laser-induced surface roughening. Our proposed apatite-coating technique using the laser- and precursor-assisted biomimetic process would be useful for the creation of apatite-coated Y-TZP ceramics for orthopedic and dental applications.

Biomimetic apatite coating on yttria-stabilized tetragonal zirconia utilizing femtosecond laser surface processing

Abstract Yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) have been used in orthopedic and dental implants because of their excellent physicochemical properties. In this study, we developed an apatite coating technique with low thermal effects for Y-TZP ceramics based on a biomimetic process using a supersaturated calcium phosphate solution (CP solution) as a coating medium. To achieve this, we performed femtosecond laser processing with low thermal effects as a surface pre-modification tool for Y-TZP ceramics. By changing the laser scanning mode, we fabricated two different submicro-/micro-structures on the Y-TZP sample. Both laser-treated samples showed increased water wettability due to ablation plasma and partly formed an apatite layer on their surfaces in the CP solution within 7 days. To further enhance the apatite-forming ability, we applied an alternate dipping process to the laser-treated sample in order to precoat the sample with apatite precursors. The laser-treated and precursor-precoated sample successfully formed an apatite layer on the entire surface in the CP solution within a shorter time period (24 h). The thus-coated apatite layer adhered to the sample so strongly that the layer remained on the sample even after the tape-detaching test. This strong adhesion may be attributed to the mechanical interlocking effects due to laser-induced surface roughening. Our proposed apatite-coating technique using the laser- and precursor-assisted biomimetic process would be useful for the creation of apatite-coated Y-TZP ceramics for orthopedic and dental applications.

Abstract 335: Activation of BKCa Channels With Rottlerin Greatly Improves Cardiac Functional Improvement Following Surgical Ischemia Associated With Cardioplegic Arrest.

Introduction: BKCa channels are thought to provide protection during ischemic insults in the heart. Rottlerin, has been implicated as a potent BKCa activator, however this has not been firmly established. The purpose of this study was two fold: 1) assess the specificity of rottlerin for BKCa channels and 2) investigate the efficacy of BKCa channel activation as a cardioprotective agent during cardioplegia/reperfusion (CP/R). Methods: Wild type and BKCa knock-out mice with and without rottlerin (only administered in CP) were subjected to an isolated heart model of CP/R. Hearts were perfused for 30 min at 37C (baseline), followed by intermittent cold crystalloid cardioplegia (intermittent St Thomas II, 10C), and normothermic, normoxic, reperfusion for 30 min. In additional studies, mechanism of rottlerin-induced cardioprotection was investigated using H9c2 cells subjected to in vitro CP/reoxygenation and assessed for mitochondrial membrane potential (TMRE) and ROS (DCFDA) production. Results: CP and 30 min reperfusion decreased LVDP (58.7 +/- 5 % baseline, n=8 ), +/- dP/dt ( 71.1+/- 6.4, 59.2 +/-6.6, % baseline respectively) and coronary flow (CF) (66.8+/-7.4, %baseline) in wild type mice. Rottlerin, (100 (n=3), 500 nM (n=5)) delivered in the CP solution dose dependently increased the recovery of LV function and CF to near baseline levels (500 nM rottlerin, LVDP: 94.1+/- 2.3, +/-dPdt: 99.6 +/- 7.2, 111.0+/- 15.0, % baseline, and CF: 128.9 +/-30.0 %baseline ). BKCa KO hearts treated with (n=4)or without (n=3) 500nM rottlerin, were similar to wt CP hearts, showing no improved cardioprotection (BKCa KO + 500 nM rott: LVDP: 57.7+/- 4.0, +/-dP/dt 69.5 +/-12.0, 59.8+/- 4.9, and CF 73 +/- 6.7). H9c2 cells subjected to in vitro CP/R, displayed reduced mitochondrial membrane potential (39% +/-.09 % decrease relative to control, p&lt;.01) and increased ROS generation (50%+/-.04 increase, p&lt;.01), both of which were dose dependently normalized by rottlerin (100 nM-1 uM) (minimum n=8). Conclusions: Activation of BKCa channels profoundly rescues ischemic damage associated with CP, likely via mitochondrial effects on improved mitochondrial membrane potential and reduced ROS generation.

Effect of low-level laser therapy on odontoblast-like cells exposed to bleaching agent

The aim of the present study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like MDPC-23 cells exposed to carbamide peroxide (CP 0.01%-2.21 μg/mL of H2O2). The cells were seeded in sterile 24-well plates for 72 h. Eight groups were established according to the exposure or not to the bleaching agents and the laser energy doses tested (0, 4, 10, and 15 J/cm(2)). After exposing the cells to 0.01% CP for 1 h, this bleaching solution was replaced by fresh culture medium. The cells were then irradiated (three sections) with a near-infrared diode laser (InGaAsP-780 ± 3 nm, 40 mW), with intervals of 24 h. The 0.01% CP solution caused statistically significant reductions in cell metabolism and alkaline phosphate (ALP) activity when compared with those of the groups not exposed to the bleaching agent. The LLLT did not modulate cell metabolism; however, the dose of 4 J/cm(2) increased the ALP activity. It was concluded that 0.01% CP reduces the MDPC-23 cell metabolism and ALP activity. The LLLT in the parameters tested did not influence the cell metabolism of the cultured cells; nevertheless, the laser dose of 4 J/cm(2) increases the ALP activity in groups both with and without exposure to the bleaching agent.

Characterization of atomic structure of oxide films on carbon steel in simulated concrete pore solutions using EELS

The atomic structure of oxide films formed on carbon steel that are exposed to highly alkaline simulated concrete pore solutions was investigated using Electron Energy Loss Spectroscopy (EELS). In particular, the effect of chloride exposure on film structure was studied in two types of simulated pore solutions: saturated calcium hydroxide (CH) and a solution prepared to represent typical concrete pore solutions (CP). It was shown that the films that form on carbon steel in simulated concrete pore solutions contained three indistinct layers. The inner oxide film had a structure similar to that of FeIIO, which is known to be unstable in the presence of chlorides. The outer oxide film mainly resembled Fe3O4 (FeIIO·Fe2IIIO3) in the CH solution and α-Fe2IIIO3/Fe3O4 in the CP solution. The composition of the transition layer between the inner and outer layers of the oxide film was mainly composed of Fe3O4 (FeIIO·Fe2IIIO3). In the presence of chloride, the relative amount of the FeIII/FeII increased, confirming that chlorides induce valence state transformation of oxides from FeII to FeIII, and the difference between the atomic structures of oxide film layers diminished.

Diffusion of Chlorin-p6 Across Phosphatidyl Choline Liposome Bilayer Probed by Second Harmonic Generation

We have investigated the diffusion of the photosensitizer Chlorin-p(6) (Cp(6)) across a egg lecithin lipid bilayer at different pH by the Second Harmonic Generation (SHG) method. Cp(6) has three ionizable carboxylic acid groups, and consequently, neutral and several ionic forms of Cp(6) are expected to be present in the pH range 3-8. The absorption spectra of Cp(6) get considerably modified in the presence of liposomes as the pH is decreased indicating that the drug liposome binding is pH dependent. The first pK(a) of interconversion (D-C) has been identified at pH ~7.0 by fluorescence measurement in an earlier work. In this work, the second pK(a) of interconversion (C-B) has been identified at pH ~4.8 by the hyper-Rayleigh scattering method. At acidic pH (3, 4, and 5), where species A, B, and C are dominant, the addition of liposomes to a Cp(6) solution generates an instantaneous rise (less than 1 s) in the second harmonic (SH) signal followed by decays whose time constants ranged from ten to hundreds of seconds. The instantaneous rise is attributed to the adsorption of Cp(6) to the outer lipid bilayer, and the decay is attributed to the diffusion of the neutral and charged (A and B) species of the drug. The observed fast and slow time constants for diffusion in the pH range 3-5 are attributed to the neutral (A) and ionic form (B) of Cp(6), respectively. At pH 6, the intensity of the generated SH signals on the addition of liposome reduced, and at physiological pH, it was too weak to be detected. These results are consistent with previous studies that show that the interaction between Cp(6) and egg-PC liposomes is pH dependent. At lower pH due to the presence of the hydrophobic species (A and B) of Cp(6), its interaction with liposomes is strong, and at higher pH, the abundance of the negatively charged hydrophilic species (C and D) decreases the interaction with the like charged liposomes. We have also studied the effect of increasing the bilayer rigidity by decreasing the temperature of the medium or by incorporating 50 mol % cholesterol in the lipid bilayer and observed that lowering of temperature has more profound effect on the diffusion rates. The characteristics of the SH signal changed significantly when liposomes incorporating 50 mol % cholesterol were used at a low (3 °C) temperature. Under these conditions, the SH signal consisted of an instantaneous (<1s) followed by a slower rise (10-90s), and then, it decayed on a much longer time scale. This slow rise of the SH signal at pH 3 and 4 may be attributed to the temperature dependent adsorption of the anionic species (B) of Cp(6) with the liposomes. Further investigations are required in order to understand clearly the pH dependent diffusion of this drug across lipid bilayers.

Enhanced immobilization of acidic proteins in the apatite layer via electrostatic interactions in a supersaturated calcium phosphate solution

Artificial materials coated with a protein–apatite composite layer have great potential in clinical applications as a third generation biomaterial. Such composite materials can be prepared by immersing a surface modified substrate into a supersaturated calcium phosphate solution (CP solution: 142 mM NaCl, 3.75 mM CaCl 2, 1.5 mM K 2HPO 4·3H 2O, buffered at pH 7.4 at 25 °C with tris(hydroxymethyl)aminomethane and HCl) supplemented with a protein. In the present study proteins of various molecular weights (MW) and isoelectric points (pI) were used to form a protein–apatite composite layer on a polymeric material to determine how the molecular properties of the protein affect the efficiency of protein immobilization (i.e. the amount of immobilized protein in the apatite layer as a percentage of the total amount of protein in solution). The results indicated that the efficiency of protein immobilization did not correlate with the MW of the protein. In contrast, the efficiency of protein immobilization was strongly related to the pI of the protein. As the pI decreased the efficiency of protein immobilization increased due to the high adsorption affinity of negatively charged acidic proteins for positively charged apatite crystals and/or apatite precursors in the CP solution. Thus, the use of acidic rather than basic proteins improves the immobilization efficiency in the present coating process.

Reversible mitochondrial uncoupling in the cold phase during liver preservation/reperfusion reduces oxidative injury in the rat model

Reversible uncoupling of the mitochondrial electron-transport chain may be one strategy to prevent intracellular oxidative stress during liver cold preservation/warm reperfusion (CP/WR) injury. 2,4-Dinitrophenol (DNP) is a potent water-soluble uncoupling agent for supplementation of the hepatic CP solution. The aim of this work was to investigate the possible influence of DNP in the CP solution on the isolated rat liver state during CP/WR. Livers were subjected to CP at 4 degrees C in sucrose-phosphate based solution (SPS) for 18 h, followed by WR for 60 min in vitro. The final concentration of DNP was 100 microM. DNP presence during the CP stage led to partial ATP level decrease accompanied by a significant diminution in liver TBARS and a prevention of antioxidant enzyme activity decrease (catalase, GSH-PO, GSH-Red) when compared with livers stored without DNP. After DNP wash-out during WR, an improvement in the mitochondrial functional state (higher respiratory control indices and ATP levels, and a decrease in V(4) respiration rates) were observed. This was concurrent with lower TBARS levels, higher antioxidant enzyme activities and significant increase of bile production. The results suggest that reversible uncoupling may be one way to influence oxidative stress associated with hepatic cold preservation.

Effects of Variation of Specific Heat on Temperature in Gaseous Combustion with Fluent Software

The combustion is modeled using one-step reaction mechanism assuming complete conversion of the fuel to CO 2 and H 2 O. This analysis illustrates the important role of the heat capacity in the prediction of peak flame temperature. The use of a constant Cp results in a significant over-prediction of the peak temperature. The average exit temperature at the outlet is also over-predicted. This over-prediction of the flame temperature can be corrected by a more realistic model for the temperature and composition dependence of the heat capacity. While the variable Cp solution produces dramatic improvements in the predicted results, further improvements are possible by considering additional models and features available in Fluent. Index terms- variable specific heat, flame temperature, flow simulation, Fluent software

A New Approach for Hydroxyapatite Coating on Polymeric Materials Using Laser-Induced Precursor Formation and Subsequent Aging

A new process, laser-induced precursor formation and subsequent aging in a supersaturated calcium phosphate aqueous solution (CP solution), was applied for coating a hydroxyapatite (HAP) film on a polymeric material, ethylene-vinyl alcohol copolymer (EVOH). Laser irradiation onto EVOH immersed in the CP solution induced the formation of CP precursors, and an HAP film composed of a submicrometer-scale cavernous structure was formed by subsequent aging in a CP solution without laser irradiation. The resulting HAP film coated on EVOH demonstrated excellent structural and chemical uniformity and cell adhesion with the CHO-K1 and BHK-21 cells. This process provides a practical technique for coating HAP onto polymeric materials.

Formation of an FGF-2-Apatite Composite Layer on Ethylene-Vinyl Alcohol Copolymer

A composite layer of fibroblast growth factor-2 (FGF-2) and low-crystalline apatite was formed on an ethylene-vinyl alcohol copolymer specimen using two types of aqueous calcium phosphate solutions supplemented with 10 !g·mL-1 FGF-2; one is a CP solution that is prepared by dissolving chemical reagents into ultrapure water and the other is an RKB solution that can be prepared by mixing clinically approved infusion fluids. In both solutions, a sufficient amount of FGF-2 for new skin tissue formation (1 !g·cm-2) was immobilized on the specimen surface.