The Synthesis and Some Properties of the First Boron-Stabilized Alkenyl Carbanions

1992 ◽  
Vol 45 (1) ◽  
pp. 57 ◽  
Author(s):  
A Pelter ◽  
K Smith ◽  
DE Parry ◽  
KD Jones
Keyword(s):  
Type Structure ◽  
High Degree ◽  
First Time

Calculations indicate a high degree of stabilization of H2BC=CH2 and that it has an allene -type structure H2B=C=CH2. Routes to boron-stabilized alkenyl carbanions have been established for the first time, and alkylation and protonation studies are described.

Genetic Diversity of Basil (Ocimum spp. - Lamiaceae) Based on RAPD Markers and Volatile Oil Constituents

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 492f-493
Author(s):  
Roberto F. Vieira ◽  
James E. Simon ◽  
Peter Goldsbrough ◽  
Antonio Figueira
Keyword(s):  
Genetic Diversity ◽  
Molecular Markers ◽  
Rapd Markers ◽  
Volatile Oil ◽  
Essential Oil Composition ◽  
Oil Composition ◽  
Traditional Medicines ◽  
The Tropics ◽  
High Degree ◽  
First Time

Essential oils extracted from basil (Ocimum spp.) by steam distillation are used to flavor foods, oral products, in fragrances, and in traditional medicines. The genus Ocimum contains around 30 species native to the tropics and subtropics, with some species naturalized and/or cultivated in temperate areas. Interand intraspecific hybridization have created significant confusion in the botanical systematics of this genus. Taxonomy of basil (O. basilicum) is also complicated by the existence of numerous varieties, cultivars, and chemotypes within the species that do not differ significantly in morphology. In this study we are using RAPD markers and volatile oil composition to characterize the genetic diversity among the most economically important Ocimum species. We hypothesize that the genetic similarity revealed by molecular markers will more accurately reflect the morphological and chemical differences in Ocimum than essential oil composition per se. Preliminary research using five Ocimum species, four undetermined species, and eight varieties of O. basilicum (a total of 19 accessions) generated 107 polymorphic fragments amplified with 19 primers. RAPDs are able to discriminate between Ocimum species, but show a high degree of similarity between O. basilicum varieties. The genetic distance between nine species and among 55 accessions within the species O. americanum, O. basilicum, O. campechianum, O. × citriodorum, O. gratissimum, O. kilimandscharium, O. minimum, O. selloi, and O. tenuiflorum will be analyzed by matrix of similarity and compared to the volatile oil profile. This research will for the first time apply molecular markers to characterize the genetic diversity of Ocimum associate with volatile oil constituent.

Characterization of SrBi2Nb2O9 Thin Films Prepared by Sol Gel Technique

1996 ◽  
Vol 459 ◽  
Author(s):  
E. Ching-Prado ◽  
W. Pérez ◽  
A. Reynés-Figueroa ◽  
R. S. Katiyar ◽  
D. Ravichandran ◽  
...  
Keyword(s):  
Thin Films ◽  
Raman Band ◽  
Sol Gel ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Ft Ir ◽  
Gel Technique ◽  
High Degree ◽  
First Time

ABSTRACTThin films of SrBi2Nb2O9 (SBN) with thicknesses of 0.1, 0.2, and 0.4 μ were grown by Sol-gel technique on silicon, and annealed at 650°C. The SBN films were investigated by Raman scatering for the first time. Raman spectra in some of the samples present bands around 60, 167, 196, 222, 302, 451, 560, 771, 837, and 863 cm−1, which correspond to the SBN formation. The study indicates that the films are inhomogeneous, and only in samples with thicknesses 0.4 μ the SBN material was found in some places. The prominent Raman band around 870 cm−1, which is the A1g mode of the orthorhombic symmetry, is assigned to the symmetric stretching of the NbO6 octahedrals. The frequency of this band is found to shift in different places in the same sample, as well as from sample to sample. The frequency shifts and the width of the Raman bands are discussed in term of ions in non-equilibrium positions. FT-IR spectra reveal a sharp peak at 1260 cm−1, and two broad bands around 995 and 772 cm−1. The bandwidths of the latter two bands are believed to be associated with the presence of a high degree of defects in the films. The experimental results of the SBN films are compared with those obtained in SBT (T=Ta) films. X-ray diffraction and SEM techniques are also used for the structural characterization.

scholarly journals Exploratory Analysis into the in vitro and in silico Activity of E. fusca Lour. (Fabaceae) Elucidates Substantial Antiplasmodial Activity of the Plant

2021 ◽  
Author(s):  
Saiful Arefeen Sazed ◽  
Ohedul Islam ◽  
Sarah L. Bliese ◽  
Muhammad Riadul Haque Hossainey ◽  
Jakaria Shawon ◽  
...  
Keyword(s):  
Antimalarial Drug ◽  
Simulation Analysis ◽  
Antimalarial Activity ◽  
Dynamics Simulation ◽  
Drug Candidate ◽  
Phytochemical Investigation ◽  
High Degree ◽  
Emergence Of Resistance ◽  
First Time

The exploration of alternative antimalarial therapeutics is a requisite for the emergence of resistance against Artemisinin. Considering the required cost and time length of classical small molecule drug discovery process, phytochemical screening of traditionally used medicinal plant which are repertoire of active compounds with antimalarial activity has become popular. To investigate the antimalarial property of traditionally used medicinal plants, a number of Erythrina spp have been reviewed systematically where less studied E. fusca has been selected for further analysis. Phytochemical investigation yielded five compounds namely; Phaseolin, Phytol, β-amyrin, Lupeol, and Stigmasterol. In-vitro antimalarial drug sensitivity HRP-II ELISA was carried out against chloroquine (CQ) sensitive 3D7 and CQ-resistant Dd2 strains. Extracts showed significant antimalarial activity against 3D7 and Dd2 strains (IC50 4.94 – 22 µg/mL) and these compounds have been reported here for the first time. Molecular docking analysis showed high binding energy (−9.0 ± 0.32 kcal/mole) indicating high degree of interaction between Phaseolin and 14 clinically important Plasmodium falciparum proteins at the active site. Stable interaction was also observed between ligand and protein from molecular dynamics simulation analysis with high free energy (−75.156 ± 11.459) that substantiates the potential of Phaseolin as an antimalarial drug candidate.

scholarly journals Late Pleistocene and Holocene small mammal (Lipotyphla, Rodentia, Lagomorpha) remains from Medvezhyi Klyk Cave in the Southern Russian Far East

2020 ◽  
Vol 324 (1) ◽  
pp. 124-145 ◽  
Author(s):  
V.E. Omelko ◽  
Y.V. Kuzmin ◽  
M.P. Tiunov ◽  
L.L. Voyta ◽  
G.S. Burr
Keyword(s):  
Late Pleistocene ◽  
Russian Far East ◽  
Far East ◽  
Relative Number ◽  
Taxonomic Diversity ◽  
14C Dating ◽  
Faunal Complexes ◽  
Extinct Genus ◽  
High Degree ◽  
First Time

Late Pleistocene-Holocene faunal complexes of small mammals (Lipotyphla, Rodentia, and Lagomorpha) from the Russian Far East are described for the first time. We used material from the Medvezhyi Klyk Cave, located in Southern Sikhote-Alin. The numerous fossil findings from the cave display a remarkable taxonomic diversity and high degree of preservation. AMS 14C dating used for determination of deposits age. The Holocene sediments were divided into three periods: Early, Middle, and Late. The Pleistocene deposits age was not exactly determined, but under approximately estimation it can reach 50–60 ka. Thirty-nine species were found, including one member of the extinct genus of arvicolins. There are six faunal complexes identified from the studied Late Pleistocene and Holocene deposits. In general, the faunal complexes characterized by the dominance of Craseomys rufocanus within rodents, Sorex caecutiens within lipotyphlans; and relatively stability composition of most number of the dominant, codominant and subdominant species. Accordingly, the faunal complexes were described by means of two determining criteria only: relative number of species; and presence or absence of certain species. The dominant species are eurytopic and so they cannot use for reconstruction of the paleoenvironment.

The New Federalists

Worldview ◽  
1973 ◽  
Vol 16 (3) ◽  
pp. 37-41
Author(s):  
Donald F. Keys
Keyword(s):  
World War Ii ◽  
Time Scales ◽  
World War ◽  
New Federalism ◽  
High Degree ◽  
First Time

The movement for a governed world has undergone a mutation recently and shows signs of again becoming an important factor in the intellectual and political worlds—for the first time since the early 1950's. The new federalism, or, if you like, neo-federalism, is no less idealistic than the old, but the time scales are different and the policies more pragmatic.Organizations and movements are not the same thing. The movement for a federated world really got under way immediately following World War II, and at first there was a high degree of congruency between the United World Federalists and the movement.

Applying Mantel’s spatial method to the case of restaurants

2020 ◽  
Vol 35 (4) ◽  
pp. 45-71
Author(s):  
Amélie Clauzel
Keyword(s):  
Spatial Analysis ◽  
Consumer Behaviour ◽  
Spatial Distance ◽  
Open Spaces ◽  
Shared Spaces ◽  
Spatial Method ◽  
High Degree ◽  
First Time

Most conventional spatial analysis approaches that are used to study the effects of interpersonal spacing are positioned on urban geographical scales and are, therefore, applicable to open spaces. This article presents the challenges and limitations of the Mantel method, which is particularly appropriate for co-presence situations in enclosed spaces, and also shows how it is implemented. Traditionally used in biostatistics and ecology, the method is deployed here for the first time in the field of consumer behaviour. When applied to the case of restaurants, it helps to identify the effects of (here, socio-spatial) distance on the greater or lesser similarity of choices between customer groups and their spending. Because it allows a high degree of use across disciplines, particularly in management sciences, the Mantel method may interest practitioners seeking to (re-)arrange shared spaces, such as workspaces, shows, aeroplane areas, spas or condominium meetings.

scholarly journals New Compounds RE(Zn,Al)8 and Yb4Zn20.3Al12.7 and their Crystal Structures

2006 ◽  
Vol 61 (7) ◽  
pp. 779-784 ◽  
Author(s):  
Ol’ga Stel’makhovych ◽  
Yurij Kuz’ma
Keyword(s):  
Intermetallic Compound ◽  
Crystal Structures ◽  
Structure Type ◽  
Type Structure ◽  
Space Group ◽  
X Ray ◽  
Structure Space ◽  
New Compounds ◽  
First Time ◽  
The Relationship

The crystal structures of several new compounds have been determined using X-ray analysis. The intermetallic compound HoZn5Al3 (a = 8.586(3), c = 16.538(5) Å , RF = 0.0413, RW = 0.0521) has its own structure type (space group I4/mmm), which has been found for the first time. The following compounds are isostructural with the previous one: YZn5.52Al2.48 (a = 8.6183(1), c = 16.5048(3) Å , RI = 0.078, RP = 0.116), DyZn4.96Al3.04 (a = 8.5887(1), c = 16.5002(3) Å , RI = 0.077, RP = 0.114), ErZn5.37Al2.63 (a = 8.5525(2), c =16.3997(5) Å , RI = 0.081, RP = 0.111), TmZn5.64Al2.36 (a = 8.70429(8), c = 16.3943(4) Å , RI = 0.088, RP = 0.095), LuZn5.58Al2.42 (a = 8.5616(1), c= 16.3052(3) Å , RI =0.081, RP =0.101). The intermetallic compound Yb4Zn20.3Al12.7 (a = 8.6183(1), c = 16.5048(3) Å , RI = 0.085, RP = 0.112) adopts the Yb8Cu17Al49 - type structure (space group I4/mmm). The relationship between the HoZn5Al3-type and the Yb8Cu17Al49-type structures is discussed.

scholarly journals Scientific support for innovative development of wheat bread long-term storage production

2020 ◽  
Vol 176 ◽  
pp. 03021
Author(s):  
Natalia Zavorokhina ◽  
Natalia Pankratyeva ◽  
Nadezhda Goncharova
Keyword(s):  
Shelf Life ◽  
Fatty Acid Esters ◽  
Wheat Bread ◽  
Innovative Development ◽  
Long Term Storage ◽  
High Degree ◽  
First Time ◽  
Term Storage ◽  
Acid Esters

Nowadays in the context of innovative development the bread intended for long-term storage is necessary in hard-to-reach areas of Sverdlovsk region, participants of expeditions, workers of logging, geological parties, etc. Taking into account the constant demand for such products, it is necessary to develop new approaches to their creation.The aim of the study was the development of long-term storage bread from wheat flour, preserving consumer characteristics throughout the shelf life.The synergism of betulin,nisin and ascorbic acid was studied for the first time when they are used together to inhibit potato bread disease (hereinafter CBH). It is proved that the use of additives, including 0.015% nisin together with 0.005% betulin to the mass of flour increases the shelf life of wheat bread up to 7 days since betulin inhibits CBH, nisin inhibits the development of mold under pH conditions in the range of 5.5-6.5.For the first time, a technique is proposed for producing betulin nanosuspension with a high degree of dispersion. The effect of betulin nanosuspension with emulsifiers of calcium lactylate, polyglycerol fatty acid esters, lecithin on the inhibition of CBH and an increase in the shelf life of wheat bread was studied.

scholarly journals Development of a THMC code for bentonites in COMSOL Multiphysics

2020 ◽  
Vol 195 ◽  
pp. 04002
Author(s):  
Ángel Yustres ◽  
Rubén López-Vizcaíno ◽  
Virginia Cabrera ◽  
Vicente Navarro
Keyword(s):  
Reactive Transport ◽  
Transport Model ◽  
Numerical Models ◽  
Swelling Pressure ◽  
Double Porosity ◽  
Comsol Multiphysics ◽  
Chemical Potentials ◽  
Definition Of ◽  
High Degree ◽  
First Time

The proposed use of active clays for the isolation of radioactive wastes in deep geological repositories has been followed by a deeper understanding of this type of soils. This increased knowledge has led to the need for both conceptual and numerical models capable of capturing the main trends in behaviour and the different couplings between different physical-chemical phenomena. In addition, the model must have a high degree of flexibility that enables it to accommodate future developments or new relevant phenomena. This work presents a numerical THMC code developed entirely on the COMSOL Multiphysics numerical implementation platform, which provides the required adaptability. This model includes, for the first time in this environment, a reactive transport model in unsaturated porous media for a relevant geochemical system (consistent with the MX-80 bentonite) together with a THM model based on a double porosity approach. The chemical potentials of water and solutes are used for the definition of thermodynamic equilibria between both porosity levels. Trends in the behaviour of a bentonite sample under oedometric conditions are satisfactorily simulated in response to a process of saturation and change in salinity conditions. Variations in swelling pressure, porosity distribution or dissolution/precipitation of the main accessory minerals are analysed and explained by means of the proposed conceptual model.

A system to impose prescribed homogenous strains on cultured cells

2001 ◽  
Vol 91 (4) ◽  
pp. 1600-1610 ◽  
Author(s):  
Christopher M. Waters ◽  
Matthew R. Glucksberg ◽  
Eugene P. Lautenschlager ◽  
Chyh-Woei Lee ◽  
Reed M. Van Matre ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Cultured Cells ◽  
Large Strain ◽  
Mechanical Strain ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Degree Of Anisotropy ◽  
High Degree ◽  
Membrane Shape ◽  
First Time

There is presently significant interest in cellular responses to physical forces, and numerous devices have been developed to apply stretch to cultured cells. Many of the early devices were limited by the heterogeneity of deformation of cells in different locations and by the high degree of anisotropy at a particular location. We have therefore developed a system to impose cyclic, large-strain, homogeneous stretch on a multiwell surface-treated silicone elastomer substrate plated with pulmonary epithelial cells. The pneumatically driven mechanism consists of four plates each with a clamp to fix one edge of the cruciform elastomer substrate. Four linear bearings set at predetermined angles between the plates ensure a constant ratio of principal strains throughout the stretch cycle. We present the design of the device and membrane shape, the surface modifications of the membrane to promote cell adhesion, predicted and experimental measurements of the strain field, and new data using cultured airway epithelial cells. We present for the first time the relationship between the magnitude of cyclic mechanical strain and the extent of wound closure and cell spreading.

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