scholarly journals Seasonal Variability of Genistein and 6-Hydroxykynurenic Acid Contents in Ginkgo biloba Leaves from Different Areas of China

2017 ◽  
Vol 12 (8) ◽  
pp. 1934578X1701200
Author(s):  
Jian B. Yao ◽  
Xin Du ◽  
Hui H. Jin ◽  
Ling Fang ◽  
Hui Min ◽  
...  
Keyword(s):  
Phosphoric Acid ◽  
Ginkgo Biloba ◽  
Quality Analysis ◽  
Natural Occurrence ◽  
Sophora Flavescens ◽  
Relative Lack ◽  
Harvesting Time ◽  
Quality Marker ◽  
First Time ◽  
The Ideal

Refined extracts of Ginkgo biloba L. leaves can protect brain tissue from diverse types of tissue damage. Preliminary experiments identified 6-hydroxykynurenic acid (6-HKA) as a central contributor to this effect, and thus as a potential active marker for drug quality analysis. In contrast, genistein is a negative quality marker for this drug, as high contents of this compound in G. biloba leaves samples are in most cases caused by adulteration with Sophora flavescens Aiton, which is added to the extract by unlawful producers in order to boost its content in flavones, which serve as a quality marker. Some publications even dispute the natural occurrence of genistein in G. biloba leaves altogether, thus claiming that its presence even in trace amounts would prove adulteration. The present study aims to resolve the influence of harvesting time and location on the contents of genistein and 6-HKA - HPLC: Agilent SB-C18 column (5 μm, 4.6×250 mm); phosphoric acid pH2.5, acetonitrile, methanol, gradient; 1 mL/min; 25°C; UV 350 nm - in G. biloba leaves. The lowest contents of 6-HKA were observed in July and August, whereas the maximum was reached in May and October. In the case of genistein - its natural occurrence in G. biloba leaves could be demonstrated under controlled conditions for the first time - the lowest contents were found in May and June, whereas the highest were detected in September and October. These results show that harvesting of G. biloba leaves for pharmaceutical use should be avoided in July and August because of the reduced 6-HKA content, as well as in September and October, the season of highest genistein production. Due to both favorable 6-HKA production and a relative lack of genistein, May was identified as the ideal harvesting month for G. biloba leaves.

The Republic

2019 ◽  
pp. 205-229
Author(s):  
Dominic Scott
Keyword(s):  
Political Theory ◽  
Left Behind ◽  
Ideal State ◽  
The Republic ◽  
Individual Justice ◽  
The Individual ◽  
Political Right ◽  
First Time ◽  
The Ideal

This chapter presents a reading of Plato’s Republic. The Republic is among Plato’s most complex works. From its title, the first-time reader will expect a dialogue about political theory, yet the work starts from the perspective of the individual, coming to focus on the question of how, if at all, justice contributes to an agent’s happiness. Only after this question has been fully set out does the work evolve into an investigation of politics—of the ideal state and of the institutions that sustain it, especially those having to do with education. But the interest in individual justice and happiness is never left behind. Rather, the work weaves in and out of the two perspectives, individual and political, right through to its conclusion. All this may leave one wondering about the unity of the work. The chapter shows that, despite the enormous range of topics discussed, the Republic fits together as a coherent whole.

Philosophy and Education

1998 ◽  
pp. 32-36
Author(s):  
Luciana Bellatalla
Keyword(s):  
Western Culture ◽  
Cultural Tradition ◽  
The World ◽  
Dialogic Approach ◽  
First Time ◽  
The Ideal

From its first appearance in western culture, philosophy has been considered able to build up reality, to educate people, and to disclose truth. Plato proposed philosophers as governors in life-long pursuit of philosophical learning. Socrates was the ideal paradigm of an educating philosopher: he tried to wake up human minds so that they could be aware of themselves and of the world, criticizing tradition and prejudices in a logically consistent perspective. A critical and dialogic approach—not by mere chance defined as "Socratic"—to problems has been considered until now the most profitable method of teaching. Socrates is a pioneer in discussing the question of a philosophical (paideia), as he defined his method "maieutic." He was not an authoritarian teacher, but a sparring partner in the process of self-education. Moreover, he considered himself as the most learned and, at the same time, the wisest in Greece, just because he was conscious of his ignorance. Therefore, he understood for the first time in our cultural tradition that knowledge is an endless process rather than a product, within marked bounds.

The Activities of the Tube Feet of Asterias Rubens L

1947 ◽  
Vol s3-88 (1) ◽  
pp. 1-14
Author(s):  
J. E. SMITH
Keyword(s):  
Forward Direction ◽  
The Other ◽  
Asterias Rubens ◽  
Ideal Form ◽  
First Time ◽  
Intrinsic Musculature ◽  
Tube Feet ◽  
Postural Muscles ◽  
The Ideal

1. An account is given of the muscular anatomy of the foot and ampulla of Asterias rubens. An intrinsic musculature of the sucker figured by Cuénot (1891) and Chadwick (1923) is shown not to be present; on the other hand, postural muscles responsible for orientating the podium, levator fibres which ‘cup’ the sucker, and radial fibres which flatten it are described and figured for the first time. 2. The role of the different muscle systems, the collagen connective tissue, and the fluid of the hydrocoel in protracting and retracting the foot, and in effecting the attachment and detachment of the sucker, is discussed. 3. Evidence is presented, to show that postural pointing of the foot is brought about by the contraction of a ring of muscles encircling the base of the podium. The orienting muscles are functionally, but not anatomically, distinct from the longitudinal fibres of the retractor sheath. 4. The ambulatory step is shown to comprise a series of linked phases of static posture and of movement. Each phase is characterized by the contraction of one member of each of the two opposing pairs of muscles engaged in the development of the step. The two pairs of muscles are (1) the anterior and posterior orienting fibres, and (2) the protractors and retractors of the foot. In its ideal form the step comprises four phases of static posture alternating with four movements. Each movement is ushered in by a reversal of the contraction-relaxation relationships of one of the two pairs of opposing muscle systems. Four such changes are possible and they occur in a sequence that ensures the orderly succession of the four movements of protraction, swing back, retraction, and swing forward, of which movements the idealized stepping cycle is composed. 5. The actual locomotory step departs from the ideal form in two respects: (1) it is liable to become disrupted by a delay in the initiation of the protraction or of the backswing movement, and (2) withdrawal of the podium occurs simultaneously with its re-orientation in the forward direction. It is pointed out that these variations are explicable on the assumption that, in the two series of opposing muscle pairs, the retractor fibres are more readily excited to contract than are their antagonists, and the anterior postural muscles than the posterior postural fibres.

Franciscan Books and their Readers

2022 ◽  
Author(s):  
René Hernández
Keyword(s):  
Space Form ◽  
Northern Italy ◽  
Ideal Space ◽  
Skilled Readers ◽  
Personal Library ◽  
Key Aspects ◽  
Cultural Agency ◽  
First Time ◽  
The Ideal

The book explores the manuscripts written, read, and studied by Franciscan friars from the thirteenth to the fifteenth centuries in Northern Italy, and specifically Padua, assessing four key aspects: ideal, space, form and readership. The ideal is studied through the regulations that determined what manuscripts should aim for. Space refers to the development and role of Franciscan libraries. The form is revealed by the assessment of the physical configuration of a set of representative manuscripts read, written, and manufactured by the friars. Finally, the study of the readership shows how Franciscans were skilled readers who employed certain forms of the manuscript as a portable, personal library, and as a tool for learning and pastoral care. By comparing the book collections of Padua’s reformed and unreformed medieval Franciscan libraries for the first time, this study reveals new features of the ground-breaking cultural agency of medieval friars.

The very first experience of biological analysis of water in Saint-Petersburg

2021 ◽  
pp. 124-130
Author(s):  
Nataliya B. Balashova ◽  
Grigorii A. Kiselev
Keyword(s):  
Quality Analysis ◽  
Northern Coast ◽  
Original Source ◽  
Saint Petersburg ◽  
Neva River ◽  
The Baltic ◽  
First Time ◽  
Heavily Polluted Area ◽  
The Gulf Of Finland ◽  
Neva Bay

The biological method of water quality analysis, for the first time, was applied in Russia during the examination of Neva Bay of the Gulf of Finland in the Baltic Sea by Wislouch S.M. Neva River was a source of drinking water in St. Petersburg and, at the same time, a discharge for all city drains. As a result, it became hazardous to health, being a source of various diseases, especially cholera. From August 1911 to September 1912 pollution studies of the Bay were made to solve the question - where to send the treated waste water of the future sewage system of St. Petersburg. In total, 37 trips were made during this time, 510 samples were taken, including 375 plankton samples and 35 benthic samples. Wysłouch S. M. gave an overview of objects collected at 265 stations located in the area of Neva Bay - from estuary of Bolshaya Neva to Kronstadt, along the southern coast of the Bay and partially along the Northern coast. He brought a list of algae, including 97 species: Algae Cyanophyceae (writing all taxa retained on original source) – 17 species, Flagellata – 19 species, Peridineae – 1, One – 30, Conjugatae – 2, Diatomaceae – 28 species, Fungi (1), Bacteria (17), Protozoa (28), Rotatoria (17). Taking into account the algae and other organisms saprobity indices, areas with different degrees of contamination were identified. All the data was put on map of the Gulf. The most heavily polluted area was the Sea channel, and the area between the Lisij Nos and Kronstadt was the cleanest.

New Hopane Triterpenoids From Lichens in the Family Physiaceae

1989 ◽  
Vol 42 (8) ◽  
pp. 1415 ◽  
Author(s):  
AL Wilkins ◽  
JA Elix ◽  
KL Gaul ◽  
R Moberg
Keyword(s):  
Methyl Ester ◽  
Natural Occurrence ◽  
Two Dimensional ◽  
Triterpene Acid ◽  
The Family ◽  
First Time

Three new hopane triterpenes have been isolated from lichens of the family Physciaceae. Two of the triterpenes, 22-hydroxyhopan-6-one (2) and 6 α-acetoxyhopan-22-ol (1b), have been characterized previously but their natural occurrence is reported for the first time, while a new triterpene acid [ aipolic acid (1c)], was isolated and characterized as the corresponding methyl ester. One- and two-dimensional 1H-1H and 13C-lH correlated n.m.r. studies have revealed methyl aipolate to be methyl 6#945;-acetoxy-22-hydroxyhopan-25-oate (1d).

scholarly journals Studies on the Chemical Diversities of Secondary Metabolites Produced by Neosartorya fischeri via the OSMAC Method

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2772 ◽  
Author(s):  
You-Min Ying ◽  
Lu Huang ◽  
Ting Tian ◽  
Cui-Yu Li ◽  
Shi-Lei Wang ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Cancer Cell Line ◽  
2D Nmr ◽  
Natural Occurrence ◽  
Fungal Metabolites ◽  
Isolation And Identification ◽  
Late Step ◽  
Neosartorya Fischeri ◽  
The One ◽  
First Time

The One Strain Many Compounds (OSMAC) method was applied to explore the chemical diversities of secondary metabolites produced by Neosartorya fischeri NRRL 181. Four pyripyropenes 1–4, eight steroids 5–11, and four prenylated indole alkaloids 12–15, were obtained from the fungus cultured in petri dishes containing potato dextrose agar (PDA). 1,7,11-trideacetylpyripyropene A (1) and 1,11-dideacetyl pyripyropene A (2) were obtained and spectroscopically characterized (1D, 2D NMR, and HR-ESI-MS) from a natural source for the first time. It offered a sustainable source of these two compounds, which were usually used as starting materials in preparing pyripyropene derivatives. In addition, as compared with all the other naturally occurring pyripyropenes, 1 and 2 possessed unique acetylation patterns that did not follow the established late-step biosynthetic rules of pyripyropenes. The natural occurrence of 1 and 2 in the fungus implied that the timing and order of hydroxylation and acetylation in the late-step biosynthetic pathway of pyripyropenes remained to be revealed. The isolation and identification of 1–15 indicated that the OSMAC method could remarkably alter the metabolic profile and enrich the chemical diversities of fungal metabolites. Compounds 1–4 exhibited no obvious cytotoxicity against the triple-negative breast cancer cell line MDA-MB-231 as compared with taxol.

scholarly journals OPTIMIZATION OF THE USE OF FLY ASH AS AN ADDITIVE PORTLAND COMPOSITE CEMENT (PCC)

2019 ◽  
Vol 4 (2) ◽  
pp. 61-72 ◽  
Author(s):  
Leni Rumiyanti ◽  
Listiani Listiani ◽  
Tika Damayanti
Keyword(s):  
Fly Ash ◽  
Setting Time ◽  
Quality Analysis ◽  
Insoluble Residue ◽  
Optimum Conditions ◽  
Free Lime ◽  
Composite Cement ◽  
Ideal Composition ◽  
Physical And Chemical ◽  
The Ideal

Research has been carried out on the optimization of the use of Lahat Fly Ash as an Additive Portland Composite Cement (PCC) which aims to determine the optimum conditions for adding Lahat fly ash to produce cement with physical and chemical requirements in accordance with SNI 7064:2014 and discover the ideal composition of cement with fly additions Lahat ash from various cement compositions. The quality analysis in making PCC cement is chemically in the form of Insoluble Residue (IR), Loss of Ignition (LOI), and free lime (FCaO) as well as the quality of physics in the form of Blaine, setting time, and cement mortar compressive strength. The results obtained after the process of making PCC cement with the addition of 14% Lahat fly ash, namely PCC cement in optimum conditions with physical and chemical requirements in accordance with SNI 7064: 2014 where the ideal composition of PCC cement manufacture is 14% Lahat fly ash, clinker 62%, 3% gypsum, 18% limestone, and 3% pozzolans in making PCC cement. Therefore, Lahat fly ash can be used as an alternative mixture in making PCC cement.

scholarly journals Urban trees as social triggers: The case of the Ginkgo biloba specimen in Tallinn, Estonia

2019 ◽  
Vol 47 (1/2) ◽  
pp. 234-256 ◽  
Author(s):  
Riin Magnus ◽  
Heldur Sander
Keyword(s):  
Ginkgo Biloba ◽  
Cultural Memory ◽  
Well Being ◽  
Urban Environments ◽  
Urban Trees ◽  
Human Organism ◽  
Cultural Space ◽  
Cultural Ideal ◽  
Human Interactions ◽  
The Ideal

Urban trees are considered to be essential and integral to urban environments, to contribute to the biodiversity of cities as well as to the well-being of their inhabitants. In addition, urban trees may also serve as living memorials, helping to remember major social eruptions and to cement continuity with the past, but also as social disruptors that can induce clashes between different ideals of culture. In this paper, we focus on a specific case, a Ginkgo biloba specimen growing at Süda Street in the centre of Tallinn, in order to demonstrate how the shifts in the meaning attributed to a non-human organism can shape cultural memory and underlie social confrontations. Integrating an ecosemiotic approach to human-non-human interactions with Juri Lotman’s approach to cultural memory and cultural space, we point out how non-human organisms can delimit cultural space at different times and how the ideal of culture is shaped by different ways of incorporating or other species in the human cultural ideal or excluding them from it.

The Temperature-Dependent Ideal Shear Strength of Solid Single Crystals

2018 ◽  
Vol 85 (3) ◽  
Author(s):  
Tianbao Cheng ◽  
Daining Fang ◽  
Yazheng Yang
Keyword(s):  
Shear Strength ◽  
Theoretical Model ◽  
Melting Point ◽  
Single Crystals ◽  
Elevated Temperatures ◽  
Absolute Zero ◽  
Temperature Dependent ◽  
Temperature Changes ◽  
First Time ◽  
The Ideal

Knowledge of the ideal shear strength of solid single crystals is of fundamental importance. However, it is very hard to determine this quantity at finite temperatures. In this work, a theoretical model for the temperature-dependent ideal shear strength of solid single crystals is established in the view of energy. To test the drawn model, the ideal shear properties of Al, Cu, and Ni single crystals are calculated and compared with that existing in the literature. The study shows that the ideal shear strength first remains approximately constant and then decreases almost linearly as temperature changes from absolute zero to melting point. As an example of application, the “brittleness parameter” of solids at elevated temperatures is quantitatively characterized for the first time.

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