Structure of the Lipopolysaccharide Core Region of the Bacteria of the Genus Proteus

2002 ◽  
Vol 55 (2) ◽  
pp. 61 ◽  
Author(s):  
E. Vinogradov ◽  
Z. Sidorczyk ◽  
Y. A. Knirel
Keyword(s):  
Core Region ◽  
Core Structure ◽  
The Other ◽  
Carboxyl Group ◽  
Open Chain ◽  
Covalent Linkage ◽  
The Core ◽  
New Type ◽  
First Time ◽  
Chain Form

The lipopolysaccharide (LPS) core structure was studied in seven rough strains of Proteus and 26 smooth strains belonging to various Proteus O-serogroups. All LPSs share a common heptasaccharide fragment, which includes two Kdo, three Hep, one Glc, and one GalA residue. Core structures differ between strains and within each strain in the presence of a variety of additional monosaccharides and non-sugar substituents. In many strains, the LPS includes a cyclic acetal of GalNAc in the open-chain form, which builds up a new type of linkage between monosaccharides. The covalent linkage of aliphatic polyamines, e.g. putrescine and spermidine, to the LPS was confirmed for the first time and the location of the amines at the carboxyl group of a GalA residue established. Analyses revealed peculiar features of the core structure, which are characteristic of P. mirabilis on one hand and P. vulgaris and P. penneri on the other hand.

Strain Analysis of Composite Frame Joints with Double Side Penetrated Diaphragms

2012 ◽  
Vol 166-169 ◽  
pp. 3277-3281
Author(s):  
Min Tong
Keyword(s):  
Stress Distribution ◽  
Strain Analysis ◽  
Steel Tube ◽  
Core Region ◽  
Steel Beam ◽  
Static Test ◽  
The Core ◽  
Composite Frame ◽  
Joint Connection ◽  
New Type

Abstract. Connection joint with penetrated diaphragm, which is better for the stressing state of the welding connection, is a new type joint for the beam and column connection. Static test and pseudo-static test are put to 17 crossing joints. The stress distribution of the steel beam and the penetrated diaphragm are discussed. The experiment shows that the penetrated diaphragm transfer most tension force of the steel beam’s upper flange to the core region of the joint, which could effectively decrease the stress and strain gradient within the connection area of the steel beam’s upper flange and steel tube column. As the result, the shear force of the core region is decreased. The front weld is avoided being surfing great tension. The ductility of the joint and the energy dissipation capacity of the structure are then increased. The type and the size of the penetrated diaphragm show great affection to the stress distribution of steel beam and penetrated diaphragm. The study achievement enriches the joint connection type of the composite structure with concrete- filled steel tube.

Stereoselective synthesis of an eleganine A core

2020 ◽  
Vol 18 (24) ◽  
pp. 4566-4568
Author(s):  
Gints Smits ◽  
Ronalds Zemribo
Keyword(s):  
Stereoselective Synthesis ◽  
Core Structure ◽  
The Core ◽  
First Time

The core structure of eleganine A – a cytotoxic indole monoterpene alkaloid – was accessed for the first time.

scholarly journals Time Profile of the Neutrino Burst from the Supernova 1987A

1988 ◽  
Vol 108 ◽  
pp. 426-427
Author(s):  
Hideyuki Suzuki ◽  
Katsuhiko Sato
Keyword(s):  
Monte Carlo ◽  
Neutrino Flux ◽  
Supernova Explosion ◽  
Time Profile ◽  
The Other ◽  
Late Time ◽  
The Core ◽  
Supernova 1987A ◽  
Theoretical Predictions ◽  
First Time

SN1987A gave us the first opportunity to study the supernova core directly by providing us the neutrino signal from the core. The observational data of the neutrino flux detected by Kamiokande[1] and IMB[2] show surprisingly good agreements with the theoretical predictions as a whole[3,4]. The fundamental concept of the collapse driven supernova explosion is confirmed for the first time. On the other hand, there are some puzzles. The most peculiar feature of the data is the 7 seconds gap of the Kamiokande data. The first 8 events of Kamiokande were detected in 2 seconds, following the 7 seconds gap and the last 3 events in 4 seconds. Of course just only 7 seconds gap is not unnatural if small neutrino flux come. But there were detected 3 events after the gap. These 3 events may not be produced by the weak flux. We can estimate the time integrated luminosity of corresponding to the last 3 events and get the large value such as 7 · 1052erg [5]. Can we get out of this inconsistency, 3 events after the 7 seconds gap? If not, we may need to consider some nonstandard mechanism of the neutrino emission at the late time. In order to investigate the probability of the case in which there is a 7 seconds gap before 3 events, we have performed Monte Carlo simulations for the simple model of neutrino flux.

Structure and Acid Strength of Opianic Acid and Its N-Methyl Oxime

1963 ◽  
Vol 16 (4) ◽  
pp. 709
Author(s):  
BH Korsch ◽  
NV Riggs
Keyword(s):  
Carboxylic Acid ◽  
Equilibrium Mixture ◽  
Acid Strength ◽  
Carboxyl Group ◽  
Open Chain ◽  
C 30 ◽  
Chain Form

In water, undissociated opianic acid exists as an equilibrium mixture containing c. 30% of lactol form (Ia) in equilibrium with open-chain form (IIa); the carboxyl group is therefore a stronger acid by c. 0.5 pK units than the measured value (pK 3.06 � 0.03) indicates. Opianic acid N-methyl oxime exists largely as the classical nitrone carboxylic acid (IIIa) in water, and is slightly weaker (pK 2.6-2.7) than opianic acid. Both compounds exist largely as cyclic forms, (Ia) and (IV), respectively, in chloroform.

scholarly journals An elastic fiber based on phononic crystals

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Farzaneh Motaei ◽  
Ali Bahrami
Keyword(s):  
Crystal Structure ◽  
Elastic Waves ◽  
Acoustic Waves ◽  
Elastic Fiber ◽  
Phononic Crystal ◽  
Phononic Crystals ◽  
Core Region ◽  
Crystal Fiber ◽  
The Core ◽  
First Time

AbstractIn this study, a novel elastic phononic crystal fiber has been presented for the first time. This proposed structure can expand the sonic communications field, significantly. In order to realize the elastic fiber performance, solid–solid phononic crystal has been utilized. The phononic crystal structure operates as cladding in surroundings and central region acts as core of fiber by elimination of rods. Incident acoustic waves with transverse polarization have confined and propagated in the core region of the phononic crystal fiber. Two types of phononic crystal fiber with different core radii have been investigated. Incident elastic waves can confine in the core region with confinement factor higher than 500. Also, longitudinal losses have been achieved low and equal to 0.35 dB/km.

scholarly journals Molecular Regions Controlling the Activity of Cng Channels

2001 ◽  
Vol 118 (2) ◽  
pp. 183-192 ◽  
Author(s):  
Holger Möttig ◽  
Jana Kusch ◽  
Thomas Zimmer ◽  
Annette Scholle ◽  
Klaus Benndorf
Keyword(s):  
Energy Difference ◽  
Core Region ◽  
The Other ◽  
Wild Type ◽  
The Core ◽  
Retinal Photoreceptors ◽  
Channel Opening ◽  
Main Portion ◽  
The Difference ◽  
Α Subunits

The α subunits of CNG channels of retinal photoreceptors (rod) and olfactory neurons (olf) are proteins that consist of a cytoplasmic NH2 terminus, a transmembrane core region (including the segments S1–S6), and a cytoplasmic COOH terminus. The COOH terminus contains a cyclic nucleotide monophosphate binding domain NBD) that is linked by the C-linker (CL) to the core region. The binding of cyclic nucleotides to the NBD promotes channel opening by an allosteric mechanism. We examined why the sensitivity to cGMP is 22 times higher in olf than in rod by constructing chimeric channels and determining the [cGMP] causing half maximum channel activity (EC50). The characteristic difference in the EC50 value between rod and olf was introduced by the NH2 terminus and the core-CL region, whereas the NBD showed a paradoxical effect. The difference of the free energy difference Δ(ΔG) was determined for each of these three regions with all possible combinations of the other two regions. For rod regions with respect to corresponding olf regions, the open channel conformation was destabilized by the NH2 terminus (Δ(ΔG) = −1.0 to −2.0 RT) and the core-CL region (Δ(ΔG) = −2.0 to −2.9 RT), whereas it was stabilized by the NBD (Δ(ΔG) = 0.3 to 1.1 RT). The NH2 terminus deletion mutants of rod and olf differed by Δ(ΔG) of only 0.9 RT, whereas the wild-type channels differed by the much larger value of 3.1 RT. The results show that in rod and olf, the NH2 terminus, the core-CL region, and the NBD differ by characteristic Δ(ΔG) values that do not depend on the specific composition of the other two regions and that the NH2 terminus generates the main portion of Δ(ΔG) between the wild-type channels.

Diaryl ketone-based hole-transporting materials for efficient perovskite solar cells

2019 ◽  
Vol 7 (11) ◽  
pp. 3226-3230 ◽  
Author(s):  
Linna Zhu ◽  
Jing Xu ◽  
Yahan Shan ◽  
Cheng Zhong ◽  
Xiaosheng Tang ◽  
...  
Keyword(s):  
Solar Cells ◽  
Perovskite Solar Cells ◽  
Hole Transport ◽  
Core Structure ◽  
The Core ◽  
Hole Transporting ◽  
First Time ◽  
Hole Transporting Materials ◽  
Dipyridyl Ketone

For the first time, dipyridyl ketone and benzophenone were used as the core structure to synthesize new hole transport materials.

scholarly journals Blockchain: A mechanism of “unorthodox” trust

2019 ◽  
Vol 2 (1) ◽  
pp. 50
Author(s):  
Valentini Grigoriadou
Keyword(s):  
Higher Education ◽  
Direct Relationship ◽  
Hierarchical Structures ◽  
The Other ◽  
Data Bases ◽  
Psychological Reality ◽  
The Core ◽  
New Type ◽  
The One ◽  
Central Data

Blockchain is a revolutionary technology which is expected to cut off proxies, reduce cost and increase speed and range. It offers transparency, safety and traceability and considerable high levels of trust. In contrast with traditional hierarchical structures and central data-bases where trust lies within institutions, blockchain’s trust is technology. It could possibly constitute the core of a new type of internet. The fact that it is developing rapidly in various fields simultaneously, will inevitably change the way of communication in the future. Although, since its onset, it was mainly used for financial exchange; it becomes evident that it is applicable in every form of exchange. Thus the new digital trust through encryption could have a determining role in redeveloping higher education. In such a context, students, instructors and teachers are in direct relationship with one another; as a result new forms of interaction are generated. The main objective is to examine on the one hand blockchain’s application in the educational sector, focusing on its potential to change educational mechanisms for the better and on the other hand its reception and the influence this technology could have on the socio-psychological reality of the involved subjects. Its application on the field of education will undoubtedly be beneficial but it is an imperative that we inspect any potential dangers as well. Since people have the need of an institution that they can trust, the creation of a world of decentralised trust is a challenge.

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