Sv Value Research Articles

Study on the interaction between aglycon of daunorubicin and calf thymus DNA by spectroscopy

The interaction between aglycon of daunorubicin (DNR-A) and calf thymus DNA (ctDNA) was investigated by UV absorption spectra and fluorescence spectra. Hypochromic effect was founded in the absorption spectra of DNR-A in the presence of ctDNA. The fluorescence intensity of DNR-A was decreased with the addition of ctDNA. Stern–Volmer plots at different temperatures proved that the quenching mechanism was a static quenching type. The binding constants of DNR-A with ctDNA at 301, 310 and 320 K were 6.203, 4.782, 3.334 × 10 4 L mol −1, respectively. The thermodynamic parameters were also obtained, which suggested that hydrophobic force might play a major role in the binding of DNR-A to ctDNA. The relative viscosity of ctDNA increased with the addition of DNR-A, at the same time the value of melting temperature of ctDNA increased in the presence of DNR-A. Effect of ionic strength showed that the addition of NaCl could not affect the binding of DNR-A and ctDNA. In addition, fluorescence quenching study indicated that K SV value for the bound DNR-A with ctDNA was lower than the free DNR-A. Fluorescence polarization and denatured DNA studies also applied strong evidences that DNR-A molecule was intercalated between the base pairs of ctDNA. All the results supported that the major binding mode of DNR-A and ctDNA was intercalation. These studies were helpful for a better understanding in the interaction of DNR-A with ctDNA, which should be beneficial to the design of new DNA targeted drugs.

Blood stasis in the descending thoracic aorta and its relationship to cardiac functional parameters

Background Spin echo Axial T1 images are used to evaluate the great vessels and cardiac structures. In some patients with depressed left ventricular ejection fraction (LVEF) the sequence fails to null blood of the descending aorta (dAo) at the level of the main pulmonary artery (MPA). This may represent stasis of blood from the aorta and reflect a decreased LVEF, stroke volume (LVSV) and/or cardiac output (CO). This finding has not systematically been studied. We evaluated the relationship between opacification of the descending aorta and cardiac functional parameters. Methods 148 consecutive cardiac MR scans performed between 7/2010 and 9/2010 that included evaluation of left ventricular function were reviewed. The T1 axial images (SE-EPI TR750TE20Flip90) were evaluated for opacification of some or all of the dAo at the level of the MPA. This was also identified in either the slice above or below this level to be considered a positive finding. The values of LVEF, SV, and CO as determined by manual tracings and application of Simpson’s rule were obtained (ViewForum, Philips, Best, The Netherlands). Results Mean LVEF value for patients with no opacification was 60% while those with any amount of opacification had a mean LVEF of 36% (p < .0001). Specificity and sensitivity for LVEF < 55 was 97% and 32% respectively, for LVEF < 45 was 95% and 40% respectively, and for LVEF < 35 was 93% and 53% respectively. The mean SV value for patients with no opacification was 96 ml while those with any amount of opacification had a mean LVSV of 58 ml (p < .0001). Specificity and sensitivity for LVSV < 50 ml was 92% and 53% respectively. The mean CO value for patients with no opacification was 6.2 L/min while those with any amount of opacification had a mean CO of 4.5 L/min (p < .0001). Specificity and sensitivity for CO < 5.0 L/min was 96% and 38% respectively. Conclusions Opacification of the descending aorta at the level of the MPA is a specific but not sensitive finding for depressed LVEF and lower than normal LVSV and CO. When this finding is observed, further evaluation of a patient’s ejection fraction should be considered.

Diffusion Control of Porous Membrane by Modifying the Nanopore Properties

We have investigated the diffusion of various solvents on nanoporous membranes with various pore size and surface energy. We have modified the size of pore channel and surface energy of porous membrane through grafting different sized alkyl chain on inorganic membranes. Typically, disc type zirconia membranes with pore size of 3 nm and silica ones with 1 nm pore were purchased from Inocermic Co. Ltd. (Germany), and the surface and pore channel was modified by either octyltriethoxysilane (OTS) with chain length approximately 1 nm or pentyltriethoxysilane (PTS) with chain length approximately 0.5 nm. The water contact angles of both OTS and PTS grafted membrane were larger than 100 degrees indicating the hydrophobically modified surface. Contact angles of hydrophilic and hydrophobic solvents were also examined to obtain exact surface energy (gamma(sv)) of grafted membrane, and the values were determined to be 56.3, 45.3, and 42.2 mN/m for ungrafted, PTS- and OTS-grafted membrane, respectively. The solvent diffusion patterns were evaluated by measuring the concentration gradient of small dye molecule, azobenzene. The diffusion coefficients of various solvents were measured on the basis of Fick's diffusion law. It was concluded that the diffusivity is dependent on the pore size for solvent with low surface tension and on the gamma(sv) value for solvent with high surface tension.

Investigation on the interaction between tamoxifen and human holo-transferrin: Determination of the binding mechanism by fluorescence quenching, resonance light scattering and circular dichroism methods

The interaction between tamoxifen (TMX) and human serum transferrin (HTF) was for the first time studied at varying pH values by fluorescence spectroscopy, circular dichroism (CD) and resonance light scattering (RLS). The fluorescence spectroscopy experiments were performed in order to study conformational changes, possibly due to a discrete reorganization of tryptophan residues during TMX–HTF binding at varying ligand concentrations, as well as quenching properties of the drug-serum transferrin complex and the differentiation between static and dynamic quenching. The binding affinity and number of binding sites were obtained for the TMX–HTF interaction at different pH. Second derivative fluorescence spectroscopy was employed for monitoring the complex and characterizing the transitions taking place in the environments of tyrosine and tryptophan (mainly tryptophans) in proteins. The variation of the K SV value suggested that hydrophobic and electrostatic interactions were the predominant intermolecular forces stabilizing the complex. The RLS technique was utilized to determine the protein type, and to investigate the effect of anticancer drugs on its determination. This is the first report of its kind. An explanation is also given of the enhancement in RLS intensity, which attributed to the new complex formation between TMX and the protein a self-aggregation process and the formation of a precipitate HTF occurred and a micelle came into being when the amount of TMX was augmented. The great increase of polarizability was one of the important factors for the enhancement of RLS and the formation of complexes. The results from synchronous fluorescence spectroscopy showed that the micro-environment around tryptophan and tyrosine demonstrated a faint red shift. The circular dichroism data revealed that the presence of TMX decreased the α-helix content of HTF and induced the remarkable unfolding of the polypeptides of the protein. This confirmed certain micro-environmental and conformational changes of the HTF molecule. The binding distance ( r) between TMX and the tryptophan residue of HTF was obtained according to the Förster theory of non-radioactive energy transfer. This study on the interaction of drugs with HTF should prove helpful for realizing the distribution and transportation of drugs in vivo, elucidating the action mechanism and dynamics of a drug at the molecular level. It should moreover be of great use for understanding the pharmacokinetic and pharmacodynamic mechanisms of the drug.

Flourescent Switch Constructed Based on Hemin-Sensitive Anionic Conjugated Polymer and Its Applications in DNA-Related Sensors

Here, a fluorescent switch is constructed combining hemin, hemin aptamer, and a newly synthesized anionic conjugated polymer (ACP), poly(9,9-bis(6'-phosphatehexyl) fluorenealt-1,4-phenylene) sodium salt (PFHPNa/PFP). In the "off-state", the fluorescence of PFP is sensitively quenched by hemin, with a high K(sv) value of approximately 10(7). While in the "on-state", the formation of the aptamer/hemin complex recovers the fluorescence intensity. The fluorescent switch is sensitive and selective to hemin. To testify the universality and practicality of the fluorescent switch, a series of label-free DNA-related sensing platforms are developed, containing three DNA sensing strategies and one ATP recognition strategy. The fluorescent switch developed is simple, sensitive, and universal, which extends applications of the anionic conjugated polymers.

Dependence of calibration sensitivity of a polysulfone/Ru(II)-Tris(4,7-diphenyl-1,10-phenanthroline)-based oxygen optical sensor on its structural parameters

The optimum performance of an optical oxygen sensor based on polysulfone (PSF)/[Ru(II)-Tris(4,7-diphenyl-1,10-phenanthroline)] octylsulfonate (Ru(dpp)OS) was checked by carefully tuning the parameters affecting the membrane preparation. In particular, membranes having thickness ranging between 0.2 and 8.0 μm with various luminophore concentrations were prepared by dip-coating and tested. The membrane thickness was controlled by tuning the solution viscosity, and was measured both by secondary ion mass spectrometry (SIMS) and by visible spectroscopy (Vis). Luminescence-quenching-based calibration was a single value of the Stern–Volmer constant ( K ′ SV ) for membranes containing up to 20 mmol Ru(dpp) g −1 PSF (1.35 μm average thickness). The K ′ SV value decreased for larger concentration. The highest sensitivity was obtained with membrane thickness around 1.6 μm, having a response time close to 1 s. Thicker membranes exhibited an emission saturation effect and were characterized by longer response time. The K ′ SV behavior was interpreted on the basis of a mathematical approach accounting for the contribution of luminescence lifetime ( τ 0), oxygen diffusion coefficient ( D O 2 ) and oxygen solubility inside the membrane ( s O 2 ) establishing the role of all of them and allowing their experimental determination. Moreover, a simple experimental way to estimate K ′ SV without needing calibration was proposed. It was based either on the light emission asymmetry or on the percent variation of light emission on passing from pure nitrogen to pure oxygen.

Konsep Earned Value dalam Aplikasi Pengelolaan Proyek Konstruksi

Earned value concept is one of monitoring technique on construction process which is based on the integrated concept of cost and time. Using integrity of time and performance of field works, earned value method can accommodate the need of performance monitoring of construction project. The aim of this research is to observe the suitability of construction cost and time in the report compared to the plan report. In this research, observed data were taken from the bridge replacement project. The results show that the project construction at the end of 4 th , 8 th and 12 th week with positive value of schedule variances, SV = 2.20 week, 0.4606 week and 0.9963 week, respectively, present the construction process is faster than schedule. While, positive value of cost variances, CV = IDR 3,543,762.17, IDR 115,583,274.67 and IDR 206,090,828.00 at the end of 4 th , 8 th and 12 th week shows that the cost of construction project is lower than budget plan. However, evaluation at the end of 16 th week shows that the SV value is -0.1946 which means that the construction works are delayed from the schedule. Based on its CV value of IDR 196,892,110.00, the cost project is lower than the budget. These results are supported with the performance index of SPI which is lower than 1 and CPI is higher than 1.

Endowing hexaphenylsilole with chemical sensory and biological probing properties by attaching amino pendants to the silolyl core

Hexaphenylsilole (HPS) was functionalized by two amino (A 2) groups, giving a new silole derivative of 1,1-bis[4-(diethylaminomethyl)phenyl]-2,3,4,5-tetraphenylsilole (A 2HPS) that is capable of detecting explosives, biomacromolecules and pH changes. A 2HPS is nonemissive when molecularly dissolved but becomes highly luminescent when aggregated. The emission of its nanoaggregates is quenched by picric acid with a high K sv value (∼1.7 × 10 5 M −1). A 2HPS can dissolve in acidic aqueous media, due to the transformation of its amino groups to ammonium-salts. The resultant nonemissive aqueous solution is turned on by increasing its pH value or adding protein or DNA.

Optical switching behavior of poly(9-alkoxyfluorene-phenylenevinylene) upon exposure to Lewis acid and base

Poly{[9-(4-hexyloxyphenyl)-9-methoxyfluorene-2,7-diyl]-alt-co-[1,4-(2,5-bisdodecyloxy)phenylenevinylene]} [P(PV-FOMe)] was synthesized and its optical property changes upon exposure to various Lewis acids were studied. The fluorescence emission of the polymer solution was completely quenched by Lewis acid such as BF 3OEt 2, AlCl 3, SiCl 4, TiCl 4, and SnCl 4. The fluorescence emission was recovered when methanol was added. The PL on/off switching behavior could be repeatedly observed by alternatively adding Lewis acid and methanol in sequence. The fluorescence quenching behavior followed the Stern–Volmer relationship with a K sv value of 1.2 × 10 4 M −1 for a quencher BF 3OEt 2. From the 1H NMR study on a model compound, we found that the PL on/off switching behavior of P(PV-FOMe) is related to the reversible bonding and cleavage of the methoxy group to/from the fluorene unit. While the morphology of a spin-coated P(PV-FOMe)-only film has some defects, defect-free coating was obtained by blending the polymer with host PVK at a level of the P(PV-FOMe) composition below 40 wt%. Among the LEDs composed of P(PV-FOMe):PVK emissive layer, the EL performance was optimal for a blend where P(PV-FOMe)-composition was 10 wt%. The maximum power efficiency and brightness were 1.33 cd/A and 1200 cd/m 2 in the device configuration of ITO/[P(PV-FOMe):PVK = 10/90]/Alq 3/Al.

The features of vacancy formation at low temperatures

Expressions for the calculation of the thermodynamic potential, enthalpy, entropy s v, and volume of vacancy formation in a simple crystal at temperatures close to absolute zero are derived. It is established that the vacancy concentration Φ as a function of the temperature T exhibits a minimum at a certain temperature T 0. At T<T 0, the Φ(T) function increases with decreasing temperature; the s v(T) value changes sign at T=T 0 and is negative at T<T 0. It is shown that the existence of the “zero-point vacancies” does not violate the third law of thermodynamics. Three new effects are predicted, and the prospects for their experimental observation are considered.

Investigation of the spectral properties of a squarylium near-infrared dye and its complexation with Fe(III) and Co(II) ions

The spectral features of the squarylium near-infrared (NIR) dye NN525 in different solutions and its complexation with several metal ions were investigated. The absorbance maximum of the dye is λ=663 nm in methanol. This value matches the output of a commercially available laser diode (650 nm), thus making use of such a source practical for excitation. The emission wavelength of the dye in methanol is λ em=670 nm. The addition of either Fe(III) ion or Co(II) ion resulted in fluorescence quenching of the dye. The Stern–Volmer quenching constant, K SV, was calculated from the Stern–Volmer plot to be K SV=2.70×10 7 M −1 for Co(II) ion. The K SV value for Fe(III) ion could not be established due to the non-linearity of the Stern–Volmer plot and the modified Stern–Volmer plot for this ion. The detection limit is 6.24×10 −8 M for Fe(III) ion and 1.55×10 −5 M for Co(III) ion. The molar ratio of the metal to the dye was established to be 1:1 for both metal ions. The stability constant, K S, of the metal–dye complex was calculated to be 3.14×10 6 M −1 for the Fe–dye complex and 2.64×10 5 M −1 for the Co–dye complex.

More about the inner filter effect: corrections of Stern–Volmer fluorescence quenching constants are necessary at very low optical absorption of the quencher

The steady-state fluorescence quenching of 2,6-bis(diethanolamino)-4,8-dipiperidino-pyrimido [5,4-d]pyrimidine (dipyridamole) by a stable nitroxyl radical 2,2,6,6-tetramethyl-piperidine-N-oxyl (TEMPO) was used to clear up the influence of the quencher light absorption on the values of the Stern–Volmer quenching constants ( K SV). We demonstrate the necessity of the K SV correction by the quencher absorbance ( A q) already at very low A q and rather high K SV. Thus, for A q<0.02 and K SV≅50 M −1 the noncorrected K SV value appears about 50% higher than the real (corrected) one. Moreover, the noncorrected K SV values do depend on the excitation and emission wavelengths, while the corrected ones are independent of them.

Magnetic Characterization of Bacterial Magnetic Particles

Mossbauer measurement, chemical analysis (ratio of Fe 2+ to total Fe content), analyses of the rotational hysteresis loss (Wr) and the magnetic viscosity coefficient (Sv) for bacterial magnetic particles covered with organic thin films (BMPs) were investigated and compared with the results for Fe 3 O 4 fine particles prepared by a chemical coprecipitation method. The calculated value of the saturation magnetization (Js) of BMPs was found to be 1.06x10.4 Wb m/kg (84.7 emu/g) using Mossbauer spectroscopy and chemical analysis. The Wr/Js versus H curve for BMPs had a stronger peak than that of Fe 3 O 4 fine particles (Sample C1). The rotational hysteresis integrals (Rh) for BMPs and Fe 3 O 4 fineparticles were 1.12 and 0.62, respectively. It is believed that they have different magnetization reversal mechanisms. The Sv value of BMPs at 127A/m was 50% smaller than that of the Fe 3 O 4 fine particles (C1). The diameter (Dact) of the activation volume (minimum volume for magnetization reversal) calculated from Sv, and the critical diameter (Dc) obtained by considering the superparamagnetic behavior for BMPs, were 39 and 22 nm, respectively. As the Fe 3 O 4 fine particles (C1) have smallerDact(31 nm) and Dc(18 nm), it may be concluded that BMPs is magnetically more stable than Fe 3 O 4 fine particles (C1).

磁性細菌ＡＭＢ‐１から分離した磁性微粒子の磁気的性質

The experimental results on Mossbauer measurement, chemical analysis (a ratio of Fe2+ to total Fe content), analyses of the rotational hysteresis loss (Wr) and the measurement of magnetic viscosity coefficient (Sv) for bacterial magnetic particles (BMP, particle diameter D=25-65 nm) were compared with those of Fe3O4 particles (D=18-45 nm) prepared by the chemical coprecipitated method. The value of saturation magnetization (Js) calculated from Mossbauer spectrum and the results of chemical analysis for BMP was 1.06×10-4 Wb m/kg. The curves of Wr/Ms versus H for BMP showed more sharp peaks than those of Fe3O4 particles. The rotational hysteresis integral (Rh) of BMP and Fe3O4 particles were 1.12 and 0.62, respectively. It was considered that they have different magnetization reversal mechanism. Sv value of BMP was 127 A/m, which was 50% smaller than that of Fe3O4 particles. The diameter (Dact) of activation volume (minimum unit volume of magnetization reversal) calculated from Sv and the critical diameter (Dc) obtained by considering the superparamagnetic behavior of BMP, were 39 and 22 nm, respectively. On the other hand, Fe3O4particles had smaller Dact (31nm) and Dc (18nm). It maybe concluded that the magnetic stability of BMP is better than that of Fe3O4 particles.

白金族金属触媒を用いた灯油予混合気の触媒燃焼

In order to develop a NOx-free catalytic combustor, a catalytic combustion using a platinum group catalyst supported on a honeycomb substrate has been examined. Measurements were made with kerosene/air mixture of 1-10 excess air ratio, 100-200mg/s of kerosene consumption rate. The measured quantities were substrate temperature, NOx, CO, CO2 concentration in the exhaust gas. The results obtained are as follows: 1. The catalytic combustor operated on a transitional region between a flame region and a entirely heterogeneous reaction region, forms a reaction zone in the gas phase of the channel without a visible flame.2. The entirely heterogeneous reaction region and the transitional region, are practically available on the viewpoint of thermal durability of the catalyst and NOx formation.3. Increasing of the catalyst thickness makes it possible to complete the catalytic combustion, because of decrease in the SV value and increase in the catalytic temperature. The effect of SV value appears mainly when the combustor is operated on the entirely heterogeneous reaction region, but the effect of the temperature mainly appears on the transitional region.

Computer Simulation of Microstructural Evolution in Thermomechanical Processing of Steel Plates.

The computer simulation model of microstructural evolution on the basis of chemical thermodynamics and classical nucleation and growth theory has been developed. The metallurgical phenomena in thermomechanical treatment of steel, such as austenite grain growth, recrystallization and growth, carbonitride precipitation and austenite to ferrite phase transformation can be predicted by the model. The influences of steel chemistry and thermomechanical condition on the transformed microstructure of 0.10C-1.5Mn-0.35Nb steel (high C-high Mn steel) and 0.06C-1.25Mn-0.035Nb steel (low C-low Mn steel) are evaluated by computer simulation. With the increase of C and/or Mn concentrations, the volume fraction of second phase increases and the ferrite grain size is refined C-high Mn steel, the transformed microstructure consists of ferrite and pearlite phases at lower cooling rates and/or larger effective austenite interfacial area per unit volume, SV. The volume fraction of second phase increases with the increase of cooling rate and/or the decrease of SV value. The second phase of the steel at higher cooling rates is bainite. The transformed microstructure of low C-low Mn steel consists of ferrite and bainite phases. The influences of the rolling condition and the cooling rate on the transformed microstructure are smaller in low C-low Mn steel. However, the transformed microstructures is apparently influenced by the start temperature of accelerated cooling.

Conformational changes of (Ca 2+-Mg 2+)-ATPase of erythrocyte plasma membrane caused by calmodulin and phosphatidylserine as revealed by circular dichroism and fluorescence studies

Two spectroscopic techniques, circular dichroism and steady-state fluorescence, were employed in order to study conformational changes of the purified, detergent-solubilized (Ca 2+-Mg 2+)-ATPase of porcine erythrocyte ghost membranes. Circular dichroism (CD) spectra in the peptide region were obtained from the purified (Ca 2+-Mg 2+)-ATPase of porcine erythrocyte ghost membranes with the aim to investigate the secondary structure of the enzyme in the presence of calmodulin (CaM) or phosphatidylserine (PS), as well as in the E 1 and E 2 states. The E 1 conformation was stabilized by 10 μM free Ca 2+, while the E 2 conformation was stabilized by 0.1 mM ethylene glycol bis(2-aminoethyl ether)- N, N, N′, N′-tetraacetic acid (EGTA). It was found that the E 1 and E 2 states of the enzyme strikingly differed in their secondary structure (66% and 46% of calculated α-helix content, respectively). In the presence of Ca 2+, PS decreased the helical content of the ATPase to 61%, while CaM to 55%. Quenching of intrinsic fluorescence of (Ca 2+-Mg 2+)-ATPase by acrylamide, performed in the presence of Ca 2+, gave evidence for a single class of tryptophan residues with Stern-Volmer constant ( K SV) of 10 M −1. Accessibility of tryptophan residues varied depending on the conformational status of the enzyme. Addition of PS and CaM decreased the K SV value to 7.6 M −1 and 8.5 M −1, respectively. In the absence of Ca 2+, K SV was 7.0 M −1. KI and CsCl were less effective as quenchers. The fluorescence energy transfer between (Ca 2+-Mg 2+)-ATPase tryptophan residues and dansyl derivative of covalently labeled CaM occurred in the presence of EGTA, but was further promoted by Ca 2+. It is concluded that the interaction of CaM and PS with (Ca 2+-Mg 2+)-ATPase results in different conformational states of the enzyme. CD and fluorescence spectroscopy allowed to distinguish these states from the E 1 and E 2 conformational forms of the ATPase.

後方体積散乱強度に及ぼす船体動揺と調査条件の影響

The influence of the ship motion and survey conditions, such as ship speed, wind direction, and wind speed, on volume back-scattering strength (SV value) was investigated by measuring echoes from an acoustically stable sea-bed. Using hull-mounted transducers, the examination was carried out by varying the speed of the vessel and the course of the vessel relative to the wind direction. The multiple regression analysis was made, with SV values as a dependent variable and the motion of the vessel and conditions of survey as independent variables. The variation of SV values had a close relation to the speed of the vessel and the course of the vessel relative to the wind, which had considerable effect on the motion of the vessel. These factors affected SV values complexly. It was concluded that the motion of the vessel induced an acoustic attenuation due to the bubbles caused by roll and pitch motions and to the beam swing caused by roll motion. The multiple regression equations obtained will be also useful as a correction of SV value in echo surveys for estimating the abundance of fish stocks.

音響による魚群量計測の精度改善に関する研究 ＩＩ 魚群分布に関するＳＶ値の時系列解析について

In the former paper, the author described the results of simulation and fundamental experiments by using Frequency Diversity Method which is a new data processing technique for Acoustic Fish Assessment System. In this paper, we describe the Statistical Characteristics of Volume Scattering Strength at the Frequency Domain by using the above equipment. The main results obtained are summarized as follows- The Power Spectrum of SV value is concentrated upon low Frequency Band. The distribution of the abundance of fish stocks is divided into two parts by 33°02.0'N line in the square-sea area from 33°01.7'N, 33°02.6'N, 131°55.7'E, 131°47.8'E. SV value which is measured by the sea bottom tracking layer is more conductive to SV value which is measured by the whole layer than the one which is measured by the upper layer. Time Series Analysis is effective against the analysis of the abundance of fish stocks.

Wetting characteristics and blood clotting on surfaces of copoly(γ‐Benzyl‐L‐glutamate, γ‐hydroxyethyl‐L‐glutamine)

The film surface of poly(gamma-benzyl-L-glutamate) (PBLG) was modified with 2-aminoethanol to enhance its hydrophilicity. Controlling the reaction conditions of PBLG and 2-aminoethanol, various types of copoly(gamma-benzyl-L-glutamate, gamma-hydroxyethyl-L-glutamine) film surfaces were obtained. Surface free energy (gamma sv), the dispersive component of gamma sv (gamma dsv), the nondispersive component of gamma sv (gamma psv), and the interfacial free energy of polymer surface with water (gamma sw), which were obtained by using the contact angle measurement and calculation method proposed by Andrade et al., were changed remarkably by the aminolysis. The gamma sv value increased after 2 h of aminolysis from 48.2 (PBLG) to 65.3 dyn/cm and gradually increased to around 70 dyn/cm after 12 h reaction. (gamma dsv) and (gamma psv) changed from 31.0 and 17.2 dyn/cm (PBLG) to 26.5 and 44.3 dyn/cm, respectively. These parameters of the material surfaces, modified over 12 h reaction, were found to be similar to those of the surfaces of canine aorta, vein, and human fibrin membrane. Blood clotting times on these polymer surfaces were comparatively longer than on siliconized glass surfaces.