scholarly journals Prothrombase—Its preparation and properties

1930 ◽  
Vol 107 (751) ◽  
pp. 271-285 ◽  
Keyword(s):  
Acetic Acid ◽  
Isoelectric Point ◽  
High Speed ◽  
Tissue Extract ◽  
Distilled Water ◽  
Compact Mass ◽  
Coagulation Process ◽  
Mammalian Blood ◽  
The Way

An attempt to reconcile the various hypotheses which have been advanced to account for the phenomena observed in the coagulation of blood necessitated the isolation from blood of those substances which are primarily involved in the coagulation process. In this paper the preparation of prothrombase from oxalated mammalian blood is described and the conditions under which it is converted into thrombase—the enzyme which converts fibrinogen into fibrin—are considered. In 1909 I described a method by which a solution of prothrombase may be obtained from bird's blood. Noncoagulable plasma is obtained from a fasting anæsthetised cockerel in the way described by Delezenne (1897). This plasma is diluted with 10 volumes of distilled water and brought to the isoelectric point for globulin by the cautions addition of acetic acid (1 per cent.). The precipitated golbulin is obtained as a compact mass by spinning the diluted plasma in a high-speed centrifuge. It is suspended in a volume of water equal to that of the original plasma and dissolved by the addition NaCl to the extent of 0·7 per cent. This solution contains prothrombase associated with fibrinogen. The addition to it of a little tissue extract (thrombokinase), and CaCl 2 to the extent 0·05 per cent. causes, within a few minutes, the formation of a solid coagulum of fibrin. The residual fluid, obtained after the removal of the fibrin, contains a large quantity of thrombase. If however, a small quantity of thrombase be added to the original fibrinogen-prothrombase solution coagulation takes place within a few seconds and the residual fluid, after removal of the fibrin, contains a large quantity of prothombase. The properties of avian prothrombase contained in such a solution were described. No attempt was made to isolate the prothrombase owing to the difficulty of obtaining stable noncoagulable birds' in large quantities.

scholarly journals Effect of different EGTA concentrations on dentin microhardness

2002 ◽  
Vol 13 (3) ◽  
pp. 188-190 ◽  
Author(s):  
Antonio Miranda da Cruz-Filho ◽  
Eduardo Augusto de Paula ◽  
Jesus Djalma Pécora ◽  
Manoel Damião de Sousa-Neto
Keyword(s):  
Acetic Acid ◽  
Statistical Analysis ◽  
High Speed ◽  
Acrylic Resin ◽  
Distilled Water ◽  
Three Solutions ◽  
Human Teeth ◽  
Tukey Test ◽  
Significant Difference ◽  
Root Dentin

The effect of 1%, 3% and 5% EGTA (ethylene glycol-bis-(b-amino-ethyl ether) N,N,N´,N´-tetra-acetic acid) on the microhardness of root dentin of the cervical third of human teeth was studied. Five newly extracted maxillary incisors were sectioned transversely at the cementoenamel junction, and the crowns were discarded. The roots were embedded in blocks of high-speed polymerized acrylic resin and cut transversely into 1-mm sections. The second section of the cervical third of the root of each tooth was sectioned and divided into four parts. Each part was placed on an acrylic disc that was used as a base for microhardness measurement. Fifty microliters of 1% EGTA, 3% EGTA, or 5% EGTA were applied to the dentin surface. Deionized and distilled water was used as control. Dentin microhardness was then measured with a load of 50 g for 15 s. Statistical analysis showed that the three concentrations of the chelating solution EGTA significantly reduced dentin microhardness when compared with water (ANOVA, p<0.01), and that there was a statistically significant difference among the three solutions (Tukey test, p<0.05).

HSCCC Separation of Three Main Compounds from the Crude Extract of Dracocephalum Tanguticum by Using Dimethyl Sulfoxide as Cosolvent

2020 ◽  
Author(s):  
Xue Yang ◽  
Yongling Liu ◽  
Tao Chen ◽  
Nana Wang ◽  
Hongmei Li ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Ethyl Acetate ◽  
Dimethyl Sulfoxide ◽  
Efficient Method ◽  
Crude Extract ◽  
High Speed ◽  
Glacial Acetic Acid ◽  
Butyl Alcohol ◽  
Preparative Hplc ◽  
Counter Current

Abstract Separation of natural compounds directly from the crude extract is a challenging work for traditional column chromatography. In the present study, an efficient method for separation of three main compounds from the crude extract of Dracocephalum tanguticum has been successfully established by high-speed counter-current chromatography (HSCCC). The crude extract was directly introduced into HSCCC by using dimethyl sulfoxide as cosolvent. Ethyl acetate/n-butyl alcohol/0.3% glacial acetic acid (4: 1: 5, v/v) system was used and three target compounds with purity higher than 80% were obtained. Preparative HPLC was used for further purification and three target compounds with purity higher than 98% were obtained. The compounds were identified as chlorogenic acid, pedaliin and pedaliin-6″-acetate.

scholarly journals The Effect of Acetic Acid Treatments on the Quality of Stored Carrot (Daucus carota L.) Seeds

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1176
Author(s):  
Hanna Dorna ◽  
Agnieszka Rosińska ◽  
Dorota Szopińska
Keyword(s):  
Acetic Acid ◽  
Distilled Water ◽  
Storage Duration ◽  
Seed Vigour ◽  
Daucus Carota L ◽  
Two Samples ◽  
Before And After ◽  
Alternaria Dauci ◽  
Acid Treatments

Alternaria dauci (J.G. Kühn) J.W. Groves et Skolko and A. radicina Meier, Drechsler et E.D. Eddy are important seed-transmitted pathogens of carrot. The aim of this study was to evaluate the effects of acetic acid treatments on the quality of stored carrot seeds. Seeds of two samples were soaked for 30 min in 0.5, 1 and 2% acetic acid. Controls included untreated seeds, seeds soaked in distilled water and seeds treated with fungicide Zaprawa Nasienna T 75 WS/DS (a.i. thiram 75%). Germination, vigour and health of untreated and treated seeds were evaluated before and after 5 and 12 months of storage at 4 and 20 °C. Seeds of both samples treated with 0.5 and 1% acetic acid were characterized by higher germination capacity after storage than untreated seeds. However, treatments with 1 and 2% acetic acid negatively affected seed vigour. Generally, seeds of both samples treated with acetic acid were characterized by lower infestation with A. alternata and A. radicina after storage than untreated seeds and seeds soaked in distilled water. Moreover, acetic acid often controlled these fungi more effectively than the fungicide. Regardless of the storage duration, infestation with fungi was higher if seeds of both samples were stored at a lower temperature.

Penetration Dynamics of Solid Particles into Liquids High-Speed Experimental Results and Modelling

2005 ◽  
Vol 473-474 ◽  
pp. 429-434 ◽  
Author(s):  
Olga Verezub ◽  
György Kaptay ◽  
Tomiharu Matsushita ◽  
Kusuhiro Mukai
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Aqueous Solutions ◽  
Particle Velocity ◽  
Weber Number ◽  
High Speed ◽  
Solid Particles ◽  
Bulk Liquid ◽  
Distilled Water ◽  
Critical Weber Number

Penetration of model solid particles (polymer, teflon, nylon, alumina) into transparent model liquids (distilled water and aqueous solutions of KI) were recorded by a high speed (500 frames per second) camera, while the particles were dropped from different heights vertically on the still surface of the liquids. In all cases a cavity has been found to form behind the solid particle, penetrating into the liquid. For each particle/liquid combination the critical dropping height has been measured, above which the particle was able to penetrate into the bulk liquid. Based on this, the critical impact particle velocity, and also the critical Weber number of penetration have been established. The critical Weber number of penetration was modelled as a function of the contact angle, particle size and the ratio of the density of solid particles to the density of the liquid.

scholarly journals Karakterisasi Ekstrak Tapioka dan Tapioka Ionik sebagai Biokoagulan dalam Proses Pengolahan Air

2018 ◽  
Vol 19 (2) ◽  
pp. 165
Author(s):  
Eka Prihatinningtyas ◽  
Agus Jatnika Effendi
Keyword(s):  
Ion Exchange ◽  
Isoelectric Point ◽  
Ftir Analysis ◽  
Active Components ◽  
Turbidity Removal ◽  
Natural Coagulant ◽  
Coagulation Process ◽  
Or Groups ◽  
Natural Coagulants ◽  
Artificial Water

ABSTRACTThe ability of tapioca to act as natural coagulants (biocoagulants) was tested using artificial water. As turbidity was added as kaolin. This research aimed to determine the compounds and or groups that act as natural coagulant and to describe the mechanism of flocculation: extraction which yields tapioca extract and ion exchange which yields ionic tapioca. Coagulation process was performed at three different initial turbidities, i.e. 50 NTU (low turbidities), 150 NTU (middle turbidities) and 300 NTU (high initial turbidites). At the same condition (coagulant dose 20 ppmv, pH 5), ionic tapioca yield better turbidity removal compared tapioca extract i.e 11.2% at low initial turbidites; 2.4% at middle initial turbidities and 12.8% at high initial turbidities. FTIR analysis  showed that tapioca extract and ionic tapioca contained of carboxyl, hydroxyl and amides groups which  can act as active components on coagulation process. The presence of those groups caused positive and negative charges (amphoter). Coagulation process ran efficiently at pH 5 because the isoelectric point is obtained at that condition.Keyword : bio coagulants, coagulation,  coagulant agents, ionic tapioca, tapioca extract,ABSTRAK Kemampuan tepung tapioka sebagai koagulan alami (biokoagulan) telah diuji dengan menggunakan limbah artifisial dari kaolin. Penelitian ini bertujuan untuk menentukan senyawa atau gugus yang berperan sebagai biokoagulan dan menjelaskan mekanisme flokulasi yang terjadi. Perlakuan awal tapioca sebelum digunakan sebagai koagulan adalah ekstraksi yang menghasilkan ekstrak tapioka  dan pertukaran ion  yang menghasilkan tapioka ionik. Proses koagulasi dilakukan pada 3 macam kekeruhan awal yaitu 50 NTU (kekeruhan rendah), 150 NTU (kekeruhan sedang) dan 300 NTU (kekeruhan tinggi). Pada kondisi operasi yang sama (dosis 20 ppmv dan pH 5), tapioka ionik memberikan efisiensi penurunan kekeruhan yang lebih tinggi, yaitu sebesar 11,0% pada kekeruhan awal 50 NTU; 2,4% pada kekeruhan awal 150 NTU dan 12,8% pada kekeruhan awal 300 NTU. Hasil analisa FTIR menunjukkan bahwa ekstrak tapioka dan tapioka ionik mempunyai gugus karboksil (-OH), gugus karboksil (-COOH) dan gugus amida (-CONH2). Keberadaan ketiga gugus tersebut menyebabkan biokoagulan ini memiliki muatan positif dan negatif sekaligus (amfoter). Proses koagulasi berjalan dengan efisien pada pH 5 karena titik isoelektrik diperoleh pada pH tersebut. Kata kunci : biokoagulan, koagulasi, agen koagulan, ekstrak tapioka, tapioka ionik

scholarly journals Forms of potassium and sodium in some species of grasses and herbage

2013 ◽  
Vol 35 (1) ◽  
pp. 87-99 ◽  
Author(s):  
Grzegorz Nowak ◽  
Henryk Panak
Keyword(s):  
Acetic Acid ◽  
Dactylis Glomerata ◽  
Mineral Fertilizer ◽  
Taraxacum Officinale ◽  
Poa Annua ◽  
Major Influence ◽  
Festuca Rubra ◽  
Distilled Water ◽  
Pot Culture ◽  
Acetic Acids

The forms of occurence of potassium and sodium were studied in the grasses <i>Dactylis glomerata</i> L., <i>Poa annua</i> L., <i>Festuca rubra</i> L. and dendelion (<i>Taraxacum officinale</i> Web.) treated with increasing mineral fertilizer doses, magnesium and microelements, under conditions of pot culture. The plants took up potassium in amounts greatly exceeding their requirement, and sodium in very small amounts. Mineral NPK doses increased in the tested plants both the content of potassium and sodium forms soluble in trichloroacetic and acetic acids and water. Magnesium and microelements had no major influence on the content of these potassium forms, but they increased the concentration of analogous forms of sodium in <i>Taraxacum officinale</i> and did not influence their accumulation in the grasses. Potassium and sodium compounds were completely extracted from the plants with trichloroacetic, whereas acetic acid extracted 88-95 percent of potassium and 66-74 percent of sodium. Distilled water extracted 70-77 and 28-33 percent of potassium and sodium, respectively.

Hydrogen Peroxide Might Bleach Natural Dentin by Oxidizing Phosphoprotein

2018 ◽  
Vol 97 (12) ◽  
pp. 1339-1345 ◽  
Author(s):  
T. Jiang ◽  
Y.R. Guo ◽  
X.W. Feng ◽  
Y. Sa ◽  
X. Yang ◽  
...  
Keyword(s):  
Amino Acids ◽  
Hydrogen Peroxide ◽  
Acetic Acid ◽  
Aromatic Amino Acids ◽  
Disodium Salt ◽  
Tooth Bleaching ◽  
Distilled Water ◽  
Fluorescent Properties ◽  
Fluorescent Intensity ◽  
Tooth Color

Recent studies suggested that bleaching agents may whiten teeth by oxidizing the fluorescent materials, which are the proteins located in the organic-inorganic interface. Therefore, we postulated that fluorescence of dentin came from dentin phosphoprotein (DPP) and that bleaching agents might bleach dentin by oxidizing DPP. Fifty-six specimens were randomly divided into 4 groups and exposed to distilled water, hydrogen peroxide (HP), ethylenediamine tetraacetic acid disodium salt (EDTA), and acetic acid for 24 h. After measuring the organic and inorganic components, fluorescence, and color characteristics of dentin before and after exposure, we found that when DPP was removed from dentin by EDTA, fluorescent intensity declined proportionally with the reduction in Raman relative intensity, and dentin was whitened considerably, with an Δ E value 6 times higher than that of the distilled water group. On the contrary, due to the incapability of acetic acid to dissolve DPP during decalcification, fluorescent intensity values and tooth color remained nearly unchanged after exposure to acetic acid. Dentin exposed to neutral HP showed no obvious morphologic and organic/inorganic component changes except for the destruction of DPP. Similarly, dramatically decreased fluorescent intensity and lightened color were found in the HP group. Moreover, DPP solution of the HP group exhibited decreased ultraviolet absorbance, especially between 250 and 300 nm, which arose from aromatic amino acids. The results indicated that DPP was responsible for the fluorescent properties of dentin and that HP might bleach dentin by the oxidization of aromatic amino acids in DPP. These findings are of great significance in promoting our further understanding of the mechanism of tooth bleaching and the fluorescent property of normal dentin.

Development of algorithms that simulate the solution of a problem by a person

2022 ◽  
Vol 1 ◽  
pp. 01006
Author(s):  
Iurii V. Filatov
Keyword(s):  
Artificial Intelligence ◽  
High Speed ◽  
Separate Study ◽  
Human Actions ◽  
History Of ◽  
Human Thinking ◽  
Problem Comparison ◽  
The Way

Some algorithms, which are often based on the use of elements of higher mathematics, possessing high speed and compact coding in algorithmic languages, are poorly mastered by most students. It can be assumed that this is due to the difficulty of presenting the principles of their work in the form of human actions in ordinary situations. Thus, a certain contradiction arises between the way of solving the problem that a person resorts to without using a computer and the way we force our computer to solve this problem. Comparison of the process of explaining algorithms speaks in favor of algorithms imitating human thinking. The discussion of the advantages of the algorithms themselves is beyond the scope of this article and undoubtedly deserves a separate study. If artificial intelligence is created, then its creator or creators will certainly be ranked among the outstanding geniuses in the history of civilization, no matter what algorithms it uses. However, so far there is no one to solve problems for us and create algorithms, so we will use all available means and try to teach this to children.

Evaluation of Arab Municipal Websites

2011 ◽  
pp. 51-65
Author(s):  
Hana Abdullah Al-Nuaim
Keyword(s):  
Wireless Networks ◽  
Growth And Development ◽  
High Speed ◽  
Public Services ◽  
Government Agencies ◽  
Immediate Feedback ◽  
Web Based ◽  
Basic Services ◽  
The Way

High speed wireless networks and mobile and web-based services are changing the way we, as consumers of information, communicate, learn, do business and receive services. Successful e-commerce models have raised the expectations of citizens to have government agencies and organizations provide public services that are timely and efficient. With the growth and development of Arab cities, especially in the capitals, life becomes a little bit harder for citizens dealing with highly bureaucratic government agencies as their demands for basic services increase. Although e-readiness in the region has grown considerably with impressive progress, Arab cities have been clearly absent from studies on worldwide e-municipal websites. In this study, an evaluation checklist for was used to evaluate official municipal websites of Arab capitals. The study found that these websites were not citizen centered, suffered from fundamental problems, had some features that were inoperable and did not follow basic guidelines for any municipal website. These sites were dominated by aesthetics and technical novelties alone, providing inactive information rather than the inclusion of interactive e-services with immediate feedback and easy to use, navigable interfaces.

scholarly journals ELECTROPHORETIC STUDIES ON PR8 INFLUENZA VIRUS

1944 ◽  
Vol 80 (6) ◽  
pp. 549-559 ◽  
Author(s):  
Gail Lorenz Miller ◽  
Max A. Lauffer ◽  
W. M. Stanley
Keyword(s):  
Molecular Weight ◽  
Influenza Virus ◽  
High Molecular Weight ◽  
Isoelectric Point ◽  
High Speed ◽  
The Other ◽  
Active Virus ◽  
Electrophoresis Method

Crude preparations of PR8 influenza virus, obtained by high-speed centrifugation, contain two electrophoretically distinct components. One of these, present to the extent of 10 to 20 per cent, was identified by electrophoresis, centrifuge, and activity tests, as an impurity similar to or identical with a high molecular weight acidic substance shown by Knight to be elaborated by normal uninfected embryos. The other component, present to the extent of 80 to 90 per cent, appeared to represent the active virus. The virus fraction was separated from the impurity by repeated fractional centrifugation. It then appeared homogeneous in the analytical centrifuge and in the Tiselius apparatus, and possessed an isoelectric point at pH 5.3 as measured by the micro-electrophoresis method.

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