bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Ag Doping on the Electronic Structure and Optical Properties of ZnO(0001) Surface
Authors: Xiang Qian , Zhao Shutao , Wu Yanning , Liu Guangdong
Published: June 2018

Using first-principle calculations, the geometrical structure, the electronic and optical properties of Ag-doped ZnO(0001) surface have been investigated. We found that Ag-doped ZnO(0001) surface is more easily formed on the first layer. On the other hand, the doped surface has gradually become an equipotential body, showing obvious metallic characteristics. We found that a new peak appeared in the low energy region after Ag doping, which was mainly due to the electron transition between the two orbital levels of Ag-4d and O-2p.
Preparation and Performance of Gallium Nitride Powders with Preferred Orientation
Authors: Kang Liping , Wang Lingli , Wang Haiyan , Zhang Xiaodong , Wang Yongqiang
Published: June 2018

The paper prepared the III-V semiconductor, hexagonal wurtzite Gallium nitride powders by calcining a gallium oxide in flowing ammonia above 900 °C (1173K). Because of the solid-state reaction process that the gallium oxide transformed to GaN through solid-state gallium oxynitrides (GaOxNy) as inter-mediates, the Gallium nitride powders which are agglomerates of tens nanometers flake crystallites retain the rod shape and grain size of raw gallium oxide and have slight (002) plane preferred orientation. The near-edge emission of Gallium nitride at 346 nm has a blue shift of 187 meV attributed to a decrease in disorder of the material that is decided by the (002) plane preferred orientation. The preferred orientation and a blue shift have some kind of reference significance to single crystal growth.
Synthesis and Luminescence Properties of the Binary/Ternary Complex of Samarium Ion with Phenacylmethyl P-Tolyl Sulfoxide and Benzoic Acid
Authors: Yang Kui-Suo , Li Wen-Xian , Bao Jin-Rong
Published: June 2018

A new ligand phenacylmethyl p-tolyl sulfoxide (denoted as L1) has been synthesized by an asymmetric synthesis method. Its novel binary complex Sm(L1)7·(ClO4)3·6H2O, and ternary complex Sm(L1)6·(L2)·(ClO4)2·6H2O (benzoic acid denoted as L2) have been synthesized. The structure and composition of the samarium complexes characterized by elemental analysis, molar conductivity, IR, UV, and 1HNMR. Additionally, fluorescence spectra measurements shows that the complexes display stronger fluorescence intensity in solid state, indicating the ligands could efficiently transfer the energy to Sm3+ ions in the complexes. The ternary complex has stronger fluorescence intensity than the binary complex.
Design Method for Proportion of Cement-Foamed Asphalt Cold Recycled Mixture
Authors: Li Junxiao , Fu Wei , Zang Hechao
Published: June 2018

Through foaming experiment of Zhongtai AH-70 asphalt, the best foaming temperature water consumption and influence factors of foamed asphalt’s foaming features are determined; By designing the proportion of foamed asphalt cold in-place recycled mixture combined with the water stability experiment, for this mixture the best foamed asphalt addition is 3%, and proportion of the mixture is RAP: fine aggregate: cement=75:23:2. Using SEM technology, the mechanism of increasing on the intensity of foamed asphalt mixture resulted by the addition of cement was analysed. This research provides reference for cement admixture’s formulation in the designing of foamed asphalt cold in-place recycled mixture.
Preparation of Magnesium Phosphate Cement and Application in Concrete Repair
Authors: Xing Sainan , Wu Chengyou
Published: June 2018

Potassium magnesium phosphate cement (MKPC) was prepared by using magnesium oxide (MgO) and potassium dihydrogen phosphate (KH2PO4, KDP). The effects of different calcination temperature, water-cement ratio and ratio on the operation of magnesium phosphate cement were studied. The effects of different water - cement ratio and ratio on the bonding strength of potassium magnesium phosphate cement and the application of potassium phosphate and magnesium cement in concrete repair and reinforcement were determined by experiments such as bending resistance, splitting, compression and bearing capacity. The experimental results show that the calcination temperature is 1100 °C, the calcination time is 1h, the settling time of magnesium oxide is 39min, and the compressive strength of one day reaches 53MPa. The water - cement ratio with the best bonding strength is 0.2, the mass ratio is 2:1.To meet the rapid repair of the construction requirements, is expected to be applied to the actual repair works.
Composite Design of Low Thermal Conductivity Mullite Brick for Application to Cement Kiln
Authors: Chen Songlin , Wang Juntao , Yuan Lin , Li Quanyou
Published: June 2018

In order to restrain cement kiln shell’s thermal loss and potential safety hazard, composite design is employed of working layer, thermal-preservation layer and thermal insulation layer. Thermal-preservation layer’s boundary and strain is analyzed and overall thermal conductivity is calculated. The result shows that sinusoidal curve boundary combination between working layer and thermal-preservation layer, slopeshape with angle of 135 degrees between thermal-preservation layer and thermal insulation layer could relieve strain concentration. Composite mullite brick comprehensive thermal conductivity decreases from the working layer 2.74W·m-1·K-1 to 1.50W·m-1·K-1. When applied in cement kiln, temperature of kiln shell is lower 50°C to 70°C than using normal bricks.
Evaluation of Cyclic Durability in Surfacemodified Layers with TiNiZr Thermoelastic Phase Transformations
Authors: Rusinov Peter , Blednova Zhesfina
Published: June 2018

This paper estimated longevity and damaging of surface materials modified by alloys with thermoelastic phase transformations, taking into account: the energy consumed for the formation of failure micro-surface in one cycle, in terms of the shape of the hysteresis loop; energy intensity of the alloy, in the light of phase composition by the results of X-ray diffraction analysis. The energy intensity and theoretical strength of ternary TiNiZr systems are calculated and plotted according to thermodynamic characteristics and phase diagrams of ternary systems. This paper carried out tests of steels with surface-modified TiNiZr layers under conditions of multicyclic fatigue and frictional friction.
Preparation and Characterization of FC Films Coated on PET Substrates by RF Magnetron Sputtering
Authors: Huang Mei-lin , Lu Sheng-guo , Du Wen-qin
Published: June 2018

Fluorocarbon (FC) films were prepared on polyethylene terephthalate (PET) plates and PET fabrics respectively by a radiofrequency (RF) magnetron sputtering technique using polytetrafluoroethylene (PTFE) as a target. Scanning electron microscope and X-ray photoelectron spectroscopy were used to investigate the morphology, structure and composition of the obtained FC films. The hydrophobicity and uvioresistant properties of the FC film coated fabric were studied. The results show that the FC films were successfully deposited on the PET substrates by a RF magnetron sputtering. The deposited films are made up of four components -CF3, -CF2-, CF- and -C-. The proportions of the four components and surface morphologies of the deposited films vary with the sputtering conditions. Compared with the original fabric samples, the hydrophobicity of the FC film coated fabrics is quite good and improved significantly.
Preparation, and Luminescence Properties of SiO2@Sm(MABA-Si)phen Core-Shell Structure Nanometer Composite
Authors: Feng Li-Na , Li Wen-Xian , Bao Jin-Rong
Published: June 2018

A novel ternary samarium complex was prepared using HOOCC6H4N(CONH(CH2)3Si- (OCH2CH3)3)2 (MABA-Si) as first ligand, and phen as second ligand. The corresponding SiO2@Sm(MABA-Si)phen core-shell structure nanometer composite was synthesized as well, and the silica spheres was the core, and the ternary samarium complex was the shell layer. The ternary samarium complex has been characterized by element analysis, molar conductivity and IR spectra. The results show that the chemical formula of the complex is Sm(MABA-Si)(phen)2(ClO4)3·2H2O. The fluorescent spectra illustrat that the luminescence properties of the samarium complex are superior. The core-shell structure of SiO2@Sm(MABA-Si)phen nanometer composite is characterized by SEM, TEM and IR spectra. The SiO2@Sm(MABA-Si)phen core-shell structure composites exhibit stronger emission intensity than the ternary samarium complex. The fluorescence lifetime of the complex and core-shell structure composite is measured as well.
Calculation of road reliability based on mathematical theory of reliability
Authors: Efimenko Vladimir , Moisejenko Rostislav
Published: June 2018

The paper presents the mathematical theory of reliability as related to the theory of road reliability. The concepts of “initial reliability” and “durability” are combined in a single algorithm. The presented theoretical method is implemented in two stages: calculation of initial reliability and calculation of durability. This sequence enables analytical calculation at given levels of initial reliability and durability of roads and their elements. It is shown that initial reliability and durability should be calculated separately. This method has proved to be effective in applied sciences dealing with the theory of structural reliability.
Criteria of choosing building structures for rooftop boiler rooms
Authors: Plotnikov Artyom , Zhilina Tatiana
Published: June 2018

The paper investigates parameters of noise and vibration distribution in the territory of residential area depending on the structural materials and power of independent heat supply systems. Rooftop boiler rooms are decentralized heat supply systems in buildings. Today, residential areas are strongly affected by noise and vibrations. Adverse effects are isolated by buildings materials, protective shields and floating floors. Rooftop boiler rooms located in Tyumen city were investigated within this research. Structures of rooftop boiler rooms were analyzed. Acoustic analysis results and the parameters of equivalent continuous sound level are presented. An option for improvement of rooftop boiler rooms structures is suggested. Comparison of capital investments in construction and installation activities is carried out. Conclusion on capital investments required for noise protection is made.
Numerical simulation of deformation behavior of aluminum alloy sheets under processing by groove pressing method
Authors: Moskvichev Evgeny , Kozulin Alexander , Krasnoveikin Vladimir , Skripnyak Vladimir
Published: June 2018

The results of theoretical estimation of capabilities of the material structure modification of 1560 aluminum alloy sheets under processing by severe plastic deformation are presented in this paper. Severe plastic deformation of flat specimens is effected by the constrained groove pressing method in original dies with trapezoidal teeth. The numerical simulation results of the sheet specimen treatment process by severe plastic deformation were used for dies designing. The stress-strain state of flat aluminum alloy specimens and the steel dies at high processing temperature, support reaction force during pressing and the degrees of plastic strain accumulation at the optimum mode of pressing were estimated. The main numerical result is the value of accumulated plastic strain in the specimen per one pressing cycle which is about 1.14. Large degrees of strain are the reasons of grain structure and material texture changes, which leads to inevitable change of its physical-mechanical properties. Increasing the number of pressing cycles leads to proportional increase of the degree of accumulated plastic strain.
Effect of fine-grained components on concrete properties and structure formation
Authors: Zimakova Galina , Solonina Valentina , Zelig Marina , Orlov Viktor
Published: June 2018

The paper investigates the influence of fine-grained components on the synthesis of new formations and structure of cellular concrete. Grain size composition was defined with the aid of a laser diffraction analyzer of particles ANALYSETTE 22 NanoTecplus. The composition of the obtained hydrated phases was studied using electron microscopy and X-ray phase analysis. The introduction of silica and aluminosilicate components with the specific surface area >350 m2/kg enabled to directly influence the mechanism of the hydrated phases formation. Complex hydrated calcium aluminosilicates of the frame structure of zeolite type and non-permanent composition were identified in the hydration products. The formation of the total set of properties is attributed to the morphological features of the hydrated phases, the nature of connections between the crystalline hydrates, and their location in the material structure. X-ray phase analysis showed that ultra-micro-dispersed components have the stimulating impact on the processes of silicate formation. With the increase in the amount of hydrated new formations and decrease in the liquid phase volume the conditions for building of strong crystal intergrowth contacts were created.
Naturally cured foamed concrete with improved thermal insulation properties
Authors: Mashkin Nikolay , Bartenjeva Ekaterina , Mansurov Rustam
Published: June 2018

The paper is dedicated to investigation on improvement of thermal insulation properties of non-autoclaved concrete by increasing aggregate stability of foamed concrete mixture. The study demonstrates influence of mineral admixtures on the foam stability index in the mortar mixture and on decrease of foamed concrete density and thermal conductivity. The effect of mineral admixtures on thermal conductivity properties of non-autoclaved concrete was assessed through different ways of their addition: to the foam and to the mortar mixture. The admixtures were milled up to the specific surface area of 300 and 600 m2/kg using an AГO-9 centrifugal attrition mill with continuous operation mode (Institute of Solid State Chemistry and Mechanochemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk). Laboratory turbulent foam concrete mixer was used to prepare foamed concrete. Thermal conductivity coefficient was defined by a quick method using “ИTП-MГ 4 “Zond” thermal conductivity meter in accordance with the regulatory documents. The impact of modifiers on the foam structure stability was defined using the foam stability index for the mortar mixture. The research demonstrated the increase in stability of porous structure of non-autoclaved concrete when adding wollastonite and diopside. Improvement of thermal and physical properties was demonstrated, the decrease of thermal conductivity coefficient reaches 0.069 W/(m×°C)
Structure and properties of ceramic brick colored by manganese-containing wastes
Authors: Stolboushkin Andrey , Akst Danil , Fomina Oksana , Ivanov Aleksandr
Published: June 2018

The given paper investigates the influence of manganese-containing wastes on bulk coloring and physical and mechanical properties of wall ceramic materials with matrix structure. Conventional research methods to study physical and mechanical properties of ceramic specimens were used in the present study. The structure and phase state of decorative ceramic materials were investigated by means of physical-chemical analysis. Authors suggested the model to form coloring layer in ceramic matrix composites based on argillaceous raw materials and coloring pigment. Macrostructure was studied on ceramic samples manufactured according to the developed method from clay loam of moderate plasticity and wastes of manganese mining. The paper provides results of pilot testing on production of colored ceramic brick. It was found that incorporation of coloring component does not decrease strength properties of ceramic matrix materials. Authors defined the palette and color code for decorative ceramic specimens manufactured with different content of coloring component of manganese mining wastes according to RGB color codes chart.
Investigation of steel to dielectric transition using microminiature eddy-current converter
Authors: Malikov Vladimir , Dmitriev Sergey , Ishkov Alexey , Katasonov Alexander , Sagalakov Anatoly
Published: June 2018

The research aims to develop a microminiature converter for electrical steel investigation. The research topic is considered relevant due to the need for evaluation and forecasting of safe operating life of electric steel products. The authors determined the capability to study steel characteristics at different depths based on variations of eddy-current converter amplitude at the steel-dielectric boundary. A microminiature transformer-type converter was designed, which enables to perform local investigations of ferromagnetic materials using eddy-current method based on local studies of the steel electrical conductivity. Having the designed converter as a basis, a hardware-software complex was built to perform experimental studies of steel at the interface boundary. A system was developed for automated converter relocation above the studied object at a specified velocity. Test results are reported for a specimen with continuous and discrete measurements taken at different frequencies. Response dependence of eddy-current converter was found to demonstrate non-linear behavior at steel to dielectric transition. The effect of gap between the eddy-current converter and the test object is investigated.
Some results on the b-chromatic number in complementary prism graphs
Authors: Bendali-Braham Amel , Ikhlef-Eschouf Noureddine , Blidia Mostafa
Published: June 2018

A b-coloring of a graph G is a proper coloring of G with k colors such that each color class has a vertex that is adjacent to at least one vertex of every other color classes. The b-chromatic number is the largest integer k for which G has a b-coloring with k colors. In this paper, we present some results on b-coloring in complementary prism graphs.
A variable neighborhood search algorithm for solving the single machine scheduling problem with periodic maintenance
Authors: Krim Hanane , Benmansour Rachid , Duvivier David , Artiba Abdelhakim
Published: June 2018

In this paper we propose to solve a single machine scheduling problem which has to undergo a periodic preventive maintenance. The objective is to minimize the weighted sum of the completion times. This criterion is defined as one of the most important objectives in practice but has not been studied so far for the considered problem. As the problem is proven to be NP-hard, and a mathematical model is proposed in the literature, we propose to use General Variable Neighborhood Search algorithm to solve this problem in order to obtain near optimal solutions for the large-sized instances in a small amount of computational time.
Bleeding Symptoms in Carriers of Hemophilia A and B
Authors: Mauser Bunschoten E P , Houwelingen J C van , Sjamsoedin Visser E J M , Dijken P J van , Kok A J , Sixma J J
Published: June 2018

In order to investigate the bleeding tendency in clinically identified carriers of hemophilia, a self-administered questionnaire was held among 135 carriers of hemophilia A and B, 25 females with relatives with hemophilia and a matched group consisting of 60 females without relatives with hemophilia. Carriers of hemophilia appeared to suffer more often from bleeding than their relatives or the matched unrelated control group. A relation was seen between factor VIII :C or IX :C activity and the tendency to bleed. Obligatory carriers with normal factor VIII :C levels showed no bleeding tendency and were in this respect similar to a group of 25 females with relatives with hemophilia. This study shows that it is important to assay factor VIII: C or IX: C also in those women in whom the carrier status has already been established otherwise.
The Bleeding Time Is Inversely Related to Megakaryocyte Nuclear DNA Content and Size in Man
Authors: Kristensen S Dalby , Bath Philip M W , Martin John F
Published: June 2018

The relation between the bleeding time and the megakaryocyte nuclear DNA content and size was evaluated in eleven consecutive patients with normal steady state thrombopoiesis undergoing thoracotomy. A statistically significant inverse correlation was found between the bleeding time and both megakaryocyte DNA content (r = −0.71, p <0.05), megakaryocyte total size (r = ‒0.58, p <0.05), megakaryocyte cytoplasmic size (r = −0.64, p <0.05) and megakaryocyte nuclear size (r = −0.58, p <0.05). The megakaryocyte total size and the megakaryocyte cytoplasmic size were statistically significantly larger in men than women (p <0.02 and p <0.03 respectively). Changes in the megakaryocytes in the bone marrow are associated with changes in primary haemostasis in normal individuals.
Thrombin-Independent Activation of Platelet Factor XIII by Endogenous Platelet Acid Protease
Authors: Lynch Garry W , Pfueller Sharron L
Published: June 2018

Platelets contain factor XIII, an A subunit zymogen form of transglutaminase (TGase), that is activated by thrombin. In addition a thrombin-independent TGase (A#) was observed. A# was formed in platelet preparations lysed at acid pH, and its generation inhibited by protease inhibitors and alkaline pH. When maximal A# activity was generated in acidified lysates no further TGase activity could be induced by subsequent treatment with thrombin. Both FXIII zymogen and A# copurified as for F XIII, from either alkaline or from acidified platelet lysates respectively, by the conventional procedure. The pH optima, Km’s for NN dimethyl casein, molecular weights, heat lability of active forms, requirements for calcium and reducing agents, and immunological characteristics of both TGases were the same. Studies with inhibitor substrates suggested that a thrombin-like cathepsin C or carboxypeptidase was responsible for A# formation. Purified F XIII zymogen could be activated directly by cathepsin C. Thus, the predominant, and probably only, TGase of platelets is factor XIII, which may be activated either by thrombin or by endogenous platelet acid protease(s).
Effects of Ethanol on Pathways of Platelet Aggregation In Vitro
Authors: Rand Margaret L , Packham Marian A , Kinlough-Rathbone Raelene L , Mustard J Fraser
Published: June 2018

Ethanol, at physiologically tolerable concentrations, did not affect the primary phase of ADP-induced aggregation of human or rabbit platelets, which is not associated with the secretion of granule contents. Potentiation by epinephrine of the primary phase of ADP-induced aggregation of rabbit platelets was also not inhibited by ethanol. However, ethanol did inhibit the secondary phase of ADP-induced aggregation which occurs with human platelets in citrated platelet-rich plasma and is dependent on the formation of thromboxane A2. Inhibition by ethanol of thromboxane production by stimulated platelets is likely due to inhibition of the mobilization of arachidonic acid from membrane phospholipids, as ethanol had little or no effect on aggregation and secretion induced by arachidonic acid or the thromboxane mimetic U46619. Rabbit platelet aggregation and secretion in response to low concentrations of collagen, thrombin, or PAF were inhibited by ethanol. Inhibition of the effects of thrombin and PAF was also observed with aspirin-treated platelets. Thus, in addition to inhibiting the mobilization of arachidonate for thromboxane formation that occurs with most agonists, ethanol can also inhibit aggregation and secretion through other effects on platelet responses.
Plasminogen Activator Inhibitor Activity in Bacterial Infection
Authors: Páramo J A , Fernández Diaz F J , Rocha E
Published: June 2018

It has been experimentally shown that endotoxin induces a marked increase in the levels of a fast-acting inhibitor of plasminogen activator (PAI). The plasma PAI activity and tissuetype plasminogen activator (t-PA) concentrations were measured in 61 patients with human septicaemia and results were compared with those observed in healthy controls. There was a markedly significant increase of PAI in plasma and platelet extracts of patients with septicaemia as compared to controls (p <0.0001). No correlation between PAI and endotoxin concentration was observed. Fibrin autography of plasma samples confirmed that activator inhibition was associated with the formation of an enzyme-inhibitor complex. t-PA activity was similar in patients and controls, whereas t-PA Ag showed a significant increase in patients (p <0.0001). A significant inverse correlation between t-PA activity and PAI was observed (p <0.05). PAI activity was higher in patients with positive blood cultures (p <0.0001) and gram-negative septicaemia (p <0.0001). There was also a significant increase of PAI levels in patients with disseminated intravascular coagulation (DIC) as compared with patients without DIC (p <0.001). We conclude that there is a marked increase of PAI in patients with sepsis. Increased PAI activity may contribute to the pathogenesis of DIC associated with septicaemia.
Effects of Reagent and Instrument on Prothrombin Times, Activated Partial Thromboplastin Times and Patient/Control Ratios
Authors: Naghibi Freshteh , Han Yangsook , Dodds W Jean , Lawrence Charles E
Published: June 2018

Activated partial thromboplastin times accumulated from two proficiency testing surveys were analyzed to determine simultaneously the effects of the method and reagent used. Prothrombin time results were reevaluated concomitantly for comparison.

A robust two-way analysis of variance was applied to determine the effect of method and reagent on APTT results. The effect of the reagent and method on the ratio of abnormal to normal plasma clotting times was determined. We found a substantial difference in ratios for the PT using different reagents on the same instrument. There was an even larger effect of reagents on APTT ratios.

Our finding of substantial reagent effects for the PT and APTT clearly support the need for standardization. We found standardization to be feasible only for the PT, and only if applied in a form consistent with the inherent error structure of the data. For the APTT the present methodology and plasma samples did not achieve consistent standardization.
Serial Determinations of PF4 and βTG: Comparisons Between Multiple Venipunctures vs a Catheter Infusion System
Authors: Strauss William , Cella Guiseppe , Myers Charles , Sasahara Arthur A
Published: June 2018

Platelet factor 4 (PF4) and beta thromboglobulin (βTG) are platelet-specific proteins which are released upon platelet aggregation and which can be accurately measured by radioimmunoassay. We devised a catheter-infusion system that enables serial determinations of these proteins.

In 20 subjects (10 healthy volunteers and 10 patients with stable coronary artery disease), we compared samples collected by individual venipunctures with those simultaneously obtained by means of a simple catheter-infusion system. At least 5 samples were obtained over a period of time which was as long as 60 min, and at least 30 min. Subjects with stable coronary artery disease were selected so that they would be expected to have stable and normal PF4 and βTG levels. Thus, elevations of either PF4 or βTG would represent artifacts secondary to sampling technique.

Analysis of the results demonstrated that the catheter-infusion system was equivalent to individual venipunctures for determination of PF4 and βTG . 16.8% of samples obtained via the catheter and 17.2% of those obtained by individual venipunctures were spuriously elevated.

A second series of studies were performed to refine the technique further by examining the impact of infusion rate and the addition of citrate phosphate dextrose (CPD) to the infusate. Ten additional subjects had catheter systems utilized in both arms simultaneously. The addition of CPD resulted in significantly less abnormal values at slower infusion rates (1 and 2.5 cc/min). At 5 cc/min D5/w or saline alone are suitable.

These investigations confirm that this simple catheter system is equivalent to individual venipunctures for determination of PF4 and βTG while avoiding patient discomfort. Also noted was the fact that a high percentage of determinations could be spuriously elevated by either technique under clinical demands. Thus, multiple determinations from the same subject are necessary to assure reproducibility.
Elasticity of Fibrin and Protofibrin Gels ls Differentially Modulated by Calcium and Zinc
Authors: Marx Gerard
Published: June 2018

The mechanical properties of fibrin and protofibrin gels in the presence of physiologic levels of Ca(II) and Zn(II) are described. As monitored with a thrombelastograph, Ca(II) (0.5–2 mM) increases the rate of development and the maximum level of gel elastic modulus (G) of fibrin and protofibrin gels. Zn(II) (10–50 μM) decreases the elastic modulus of those gels, even in the presence of a large excess of Ca(II). This contrasts with the ability of both divalent cations to increase fibrin and protofibrin gel turbidity. Unlike the turbidity or fibre thickness of fibrin and protofibrin gels, both of which are increased by these cations, gel elasticity is increased by Ca(II) but decreased by Zn(II). h is demonstrated that Ca(II) and Zn(II) modulate fibrin and protofibrin gels independently of one another, and that they have opposing effects on the mechanical properties of the gels. The disparity between the visual (turbidity, TEM) and the mechanical (elasticity) properties of (proto)fibrin gels indicates the need for new conceptual and analytic paradigms.
Resolution and Reconstitution of Interplatelet Recognition During Aggregation
Authors: Agam Galila , Livne Avinoam
Published: June 2018

In previous studies it was shown that fixed platelets bearing covalently-bound fibrinogen participate passively in release-related aggregation, and that thrombospondin is the released compound which specifically and selectively recognizes the affixed fibrinogen. The present study demonstrates that the phenomenon of passive participation is also obtained with fixed platelets bearing covalently-bound thrombospondin. Moreover, a full resolution and reconstitution of interplatelet recognition during aggregation was obtained with two different systems: (a) fixed platelets bearing affixed fibrinogen were caused to aggregate when stirred and supplemented with soluble thrombospondin; (b) fixed platelets bearing fibrinogen and fixed platelets bearing thrombospondin, each uncapable of undergoing aggregation, aggregated when combined and stirred. It is concluded that fibrinogen and thrombospondin play a major role in the molecular mechanism of interplatelet recognition during aggregation.
Tissue Plasminogen Activator in Human Megakaryocytes and Platelets: Immunocytochemical Localization, Immunoblotting and Zymographic Analysis
Authors: Jeanneau C , Sultan Y
Published: June 2018

Two approaches were used to identify and characterize the presence of tissue plasminogen activator (t-PA) in megakaryocytes and platelets. We investigated the fibrinolytic activity of human megakaryocytes (MK) and platelets. The presence of t-PA antigen in megakaryocytes and platelets was demonstrated using immunocytochemical techniques and polyclonal or monoclonal antibodies specific for t-PA. When cells were applied to fibrin plates, lysis zones developed around isolated human megakaryocytes, whereas no fibrinolytic activity appeared when either intact washed platelets or platelet lysate were deposited. After SDS-PAGE of platelet and MK extracts (Triton X-100) immunoblotting and peroxidase staining identified t-PA antigen in several bands. Zymographic analysis of SDS-PAGE carried out on fibrin film overlays identified one or two zones corresponding to free or complexed t-PA. These results indicate that t-PA is present in platelets as well as in the precursor cells, however, in platelets, t-PA may not be immediately available for plasminogen activation and fibrin degradation. From our findings and from previous work of others, it appears that platelets may either activate or inhibit the fibrinolytic system. Therefore the conditions of plasminogen activation by platelet t-PA and plasmin inhibition by platelet α2-antiplasmin or other inhibitors have to be precised before the role of platelets in clot dissolution is understood.

The physiological role of platelets in fibrinolysis and clot dissolution remains unclear. In 1953, the antifibrinolytic activity of blood platelets was demonstrated (1) and in the early 1960’s a fibrinolytic activity, increasing with platelet concentration in the experimental system, was shown (2, 3). In 1979, it was demonstrated that metabolically active platelets were necessary for platelets to play a role in the fibrinolytic system (4). More recently it was established by Plow and Collen (5) that the specific plasmin inhibitor, α2-antiplasmin is a constituent of platelet α-granules.

In the present study, we investigated the fibrinolytic components and activity of human megakaryocytes and platelets, using zymographic and immunochemical techniques. We report here our observations that human megakaryocytes and platelets contain tissue plasminogen (t-PA) which possesses fibrinolytic activity.
Fibrinolysis by Bile
Authors: King Burnham J.
Published: June 2018

Fibrinolytic activity is described in the bile of man and of several species of mammal. This activity can be precipitated from whole bile by ammonium sulphate, by acetone, and by a chlor of orm/methanol partition technique. It behaves as an anion at pH 7.4. Ammonium sulphate precipitated bile is caseinolytic, and fibrinolytic on a heated fibrin plate. It gives a peak of fibrinolytic activity on column chromatography with sephadex G50 at Kav = 0.3, suggesting a molecular weight of ± 15,000.
Use of the Megathrombocyte to Demonstrate Thrombopoietin
Authors: Marc Weiner , Simon Karpatkin
Published: June 2018

Quantitation of megathrombocyte (large platelet) number was used as an assay for the detection of a humorally-transmitted thrombopoietic stimulus, thrombopoietin. Donor guinea pigs were depleted of circulating platelets by the injection of rabbit anti-guinea pig platelet antibody. Plasma from these donor guinea pigs, when injected into recipient guinea pigs raised their platelet count 1.5 fold and their megathrombocyte number 2.7 fold when compared to plasma injected from donor guinea pigs with normal platelet counts. A lag period of 4 to 5 days preceded the rise in platelet count and megathrombocyte number.
Cold Promoted Activation of Factor VII
Authors: Gjønniess H
Published: June 2018

Several known activators of the plasma kallikrein system were tested for the ability to induce cold promoted activation of factor VII.

All the prekallikrein activators tested (EACA, trypsin, acetone, urokinase, kaolin, Liquoid, ellagic acid) revealed generation of factor VII activator activity (CPA). Simultaneously the plasma kallikrein system was activated. A good correlation was demonstrated between the factor VII activation and the kallikrein activity.

Glandular kallikrein, bradykinin, or kallidin revealed no effect on the coagulation system. Thus, the correlation between the factor VII activation and the kallikrein system seemed to be restricted to plasma kallikrein.
Cold Promoted Activation of Factor VII
Authors: Gjønnæss H
Published: June 2018

The cold promoted shortening of the thrombotest times induced by incubation of plasma with prekallikrein activators for 20 hours at 0° C is due to activation of factor VII. No change was recorded for the other coagulation factors. The activation was strong, as the presence of 1 per cent cold activated factor VII reduced the thrombotest time of factor VII deficient plasma from 115 to 38.7 seconds.

The activation of factor X by the cold activated factor VII occurred in the course of seconds, in the presence of calcium and thromboplastin. Cold promoted activation of factor VII also implied reduced cephalin time, probably via traces of thrombin inducing intrinsic factor X activator activity during the clotting test.

Generation of cold promoted activator activity (CPA) was independent of coagulation factors V, VIII, IX, X, XI, and calcium, but factor XII was a prerequisite. Of factor VII even traces were sufficient for the generation of CPA. The activation of the kallikrein system, that occurs in parallel with the cold promoted activation of factor VII, occurred both in factor VII deficient plasma and in ordinary control plasma. In the reaction sequence, the activation of factor VII therefore is less likely to be the first step, it possibly is a result of activation of the kallikrein system.
The Effect of Staphylocoagulase on the Subunit Structure of Human Fibrin
Authors: Tager M , King M. J. S
Published: June 2018

Fibrin clots resulting from the action of coagulase thrombin were subjected to Polyacrylamide gel electrophoresis in the presence of hirudin or of heparin to exclude the action of biothrombin.

Alpha, beta, and gamma polypeptide chains were resolved not differing from those induced by the action of thrombin on fibrinogen.

No evidence was found of any further degradation of any of the polypeptide chains.

Although coagulase thrombin fails to activate factor XIII at calcium ion concentrations effective for the cross-linking of fibrin by thrombin, higher concentrations of calcium lead to the activation of factor XIII by coagulase thrombin, resulting in gamma dimer formation.

The data support the evidence that coagulase thrombin, like biothrombin, acts as a limited proteolytic agent on fibrinogen.
The Effect of Molecular Iodine on Platelet Aggregation in Vitro
Authors: Kikugawa Kiyomi
Published: June 2018

When rabbit platelet-rich plasma was treated with 1-2 mM molecular iodine, marked irreversible aggregation of platelets was observed. The aggregation was characterized by inhibition by 1 mM reduced glutathione, acceleration by 0.1 mM NEM, and no interference with EDTA and adenosine which are powerful inhibitors of aggregation induced by ADP. Molecular iodine at a concentration of 0.5 mM did not induce aggregation and caused more than 60% inhibition of ADP- and collagen-induced aggregation. These findings indicated that the aggregation by molecular iodine was in quite different mechanisms from those by other aggregating agents such as ADP, and suggested that platelet aggregation by molecular iodine and ADP was greatly regulated by sulfhydryl groups.
The Influence of Benzamidine Derivatives on Human Platelet Function
Authors: Glusa Erika , Barthel Wolfgang , Markwardt Fritz
Published: June 2018

The influence of derivatives of benzamidine, benzylamine and phenylguanidine on platelet function was investigated in vitro. Among the compounds tested 4-nitro-benzoic acid 4’-amidinoanilide, 4-aminobenzoic acid 4’-amidinoanilide, 4-amidino-benzoic acid anilide and 4-amidinobenzoic acid 3’,4’-dimethoxyanilide were found to be potent inhibitors of platelet aggregation induced by ADP, collagen and thrombin. Other platelet functions, such as the thrombin-induced amine liberation, serotonin and adenosine uptake, retraction and phosphodiesterase activity, were not influenced. The action of the benzamidine derivatives, known to be thrombin inhibitors, is not caused by an inhibition of the clotting enzyme, but it seems to be mainly due to the prevention of the ADP effect on platelets.
Platelet Function Long after Arterial and Venous Thrombosis
Authors: O’Brien J. R , Etherington M , Jamieson Sandra , Klaber M. R , Lincoln S. V
Published: June 2018

One hundred and seventeen people, including controls and patients after recovery from myocardial infarction (MI) or deep vein thrombosis (DVT) and of both sexes, have been subjected to a battery of tests thought to test platelet function. The object was to find differences which might indicate whether long-term platelet abnormalities could be demonstrated. Differences between MI and DVT results might suggest that different mechanisms are involved. The bleeding time tests were shorter in MI patients of both sexes than their respective controls and male controls have shorter bleeding times than females, but patients with DVT did not differ significantly from the controls. Tests involving platelet factor 3 and platelet factor 4 show increased activity in one or both patient groups. Thus there is considerable evidence of increased platelet/plasma activity in these disease states. The aggregation induced by thrombin was less in patients with MI and DVT than in the controls.

An analysis suggests that the different groups of tests are not related and so presumably are measuring independent functions. Multiple discriminant analysis achieved for each sex moderately good separation of the three groups, namely controls, MI and DVT. These findings support the concept that there are long-term but partly differing abnormalities in MI and DVT which may predispose to thrombosis. The precise mechanisms involved need further clarification.
Antithrombin III Deficiency in Maturity Onset Diabetes Mellitus and Atherosclerosis
Authors: Banerjee R. N , Sahni A. L , Kumar V , Arya M
Published: June 2018

Antithrombin III activity and thrombin times were assayed in maturity onset diabetics, atherosclerotic patients and normal subjects. There was a close correlation between the Antithrombin III activity and thrombin times in all three groups. Reductions in these measurements in diabetes mellitus and atherosclerosis, independent of thromboembolic phenomena, support the theory of Antithrombin III deficiency in these diseases.
Factors Regulating Plasma Protein Synthesis IV. Influence of Fragments D and E on Plasma Fibrinogen Concentration
Authors: Bocci V , Conti T , Muscettola M , Pacini A , Pessina G. P
Published: June 2018

Rabbit fibrinogen digest products (FDP) have been separated by Pevikon block electrophoresis yielding fragments D, E and other unidentified FDP.

The fragments were injected into rabbits. Surprisingly, as little as 4.3 mg of fragment D elicited a significant increase in plasma fibrinogen concentration 24 hr after injection. The stimulating activity of fragment D is at least 10-fold higher than that of fragment E.
Studies on the Interaction of Warfarin and Clofibrate in Man
Authors: O’Reilly R. A , Sahud M. A , Robinson A. J
Published: June 2018

To evaluate the basis for the hemorrhagic diathesis associated with oral anticoagulant therapy plus the hypolipidemic agent clofibrate, this interaction was studied in 8 normal subjects. Administration of clofibrate 2.0 g/day alone for 14 days had no effect on the platelet count, bleeding time, platelet aggregation, plasma adenosine diphosphatase, platelet release of adenosine diphosphate and adenosine triphosphate, platelet-collagen adhesion, one-stage prothrombin time, or vitamin K-dependent clotting factors (II, VII, IX and X) but significantly reduced platelet adhesiveness and epinephrine-induced platelet aggregation. After addition of large single doses of sodium warfarin, 1.5 mg/kg body weight, to the clofibrate regimen, all values remained within the normal range, including platelet adhesiveness, except epinephrine-induced platelet aggregation. The one-stage prothrombin activity and clotting factors II and X were significantly lower with warfarin plus clofibrate than with warfarin alone, but the plasma level of warfarin was unchanged. Co-administration of sodium warfarin and clofibrate for 21 days augmented the hypoprothrombinemia observed in long-term therapy with warfarin alone but caused no significant change in the plasma warfarin level. It is concluded that the hemorrhagic complications of therapy with warfarin plus clofibrate result primarily from the more rapid decline in the activities of clotting factors II and X and perhaps also from the reduced platelet aggregation.
Acute Promyelocytic Leukemia in a Patient with Hemophilia
Authors: Green D.
Published: June 2018

Factor VIII levels are usually elevated in patients with leukemia, and recently markedly increased levels of factor VIII were described during the relapses of acute lymphoblastic leukemia in a boy with previously documented hemophilia. In this paper we describe a young man with severe classical hemophilia who developed acute promyelocytic leukemia. In contrast to the findings noted above, infused factor VIII in this patient rapidly disappeared, with a half-life of only 4-8 h (expected: 12 h). In addition, the half-life of fibrinogen was 20 h (expected: 72 h), there was marked thrombocytopenia, and decreased levels of factor V. It is suggested that the rapid consumption of factor VIII is consistent with the syndrome of “consumption coagulopathy” which was present as a complication of his acute promyelocytic leukemia.
What makes people approve or condemn mind upload technology? Untangling the effects of sexual disgust, purity and science fiction familiarity
Authors: Laakasuo Michael , Drosinou Marianna , Koverola Mika , Kunnari Anton , Halonen Juho , Lehtonen Noora , Palomäki Jussi
Published: June 2018

The idea of separating a person’s consciousness and transferring it to another medium—'mind upload'—is being actively discussed in science, philosophy, and science fiction. Mind upload technologies are currently also being developed by private companies in Silicon Valley, and similar technological developments have received significant funding in the EU. Mind upload has important existential and ethical implications, yet little is known about how ordinary people actually feel about it. The current paper aims to provide a thorough moral psychological evaluation about various cognitive factors that explain people’s feelings and reactions towards the use of mind upload technology. In four studies (including pilot) with a total of 952 participants, it was shown that biological and cultural cognitive factors help to determine how strongly people condemn mind upload. Both experimental manipulations in a laboratory and cross-sectional correlative online study designs were employed. The results showed that people who value purity norms and have higher sexual disgust sensitivity are more inclined to condemn mind upload. Furthermore, people who are anxious about death and condemn suicidal acts were more accepting of mind upload. Finally, higher science fiction literacy and/or hobbyism strongly predicted approval of mind upload. Several possible confounding factors were ruled out, including personality, values, individual tendencies towards rationality, and theory of mind capacities. Possible idiosyncrasies in the stimulus materials (whether consciousness is uploaded onto a computer, chimpanzee, artificial brain, or android; and whether the person’s body physically dies during the process) were ruled out. The core findings inform ongoing philosophical discussions on how mind upload could (or should) be used in the future, and imply that mind upload is a much more salient topic for the general population than previously thought.
Theoretical study of terahertz active transmission line oscillator based on RTD-gated HEMT
Authors: Mao Xurui , Xie Sheng , Zhu Changju , Geng Zhaoxin , Chen Hongda
Published: June 2018

In this paper, a new kind of terahertz oscillator is presented using plasma wave excitation in a resonant tunnel diode (RTD) gated high electron mobility transistor (HEMT). The plasma wave arising from the RTD-gated HEMT is equivalent to active transmission lines and induces negative differential conductance (NDC) of the oscillator. The proposed RTD-gated HEMT oscillator is more compact and has higher oscillation frequency than the transmission line loaded traditional RTD oscillator duo to plasma wave effect. This paper analyses and calculates the oscillation conditions, the relationships between device structures, oscillation frequency and the output power of the oscillator. The presented work may provide a new concept for fabricating terahertz oscillator.