Chirality Induction in the Synthesis of Ag29 Nanoclusters with Asymmetric Structure

2021 ◽  
Author(s):  
Hiroto Yoshida ◽  
Miwa Kuzuhara ◽  
Riku Tanibe ◽  
Tsuyoshi Kawai ◽  
Takuya Nakashima
Keyword(s):  
Asymmetric Structure ◽  
Chirality Induction

Artefact in 20Å-Resolution Electron Images of Negatively Stained Twodimensional Membrane Protein Crystals

1982 ◽  
Vol 40 ◽  
pp. 92-93
Author(s):  
Douglas L. Dorset ◽  
Barbara Moss
Keyword(s):  
Electron Scattering ◽  
Cross Correlation ◽  
Transmission Function ◽  
Group Symmetry ◽  
Asymmetric Structure ◽  
Object Model ◽  
Phase Object ◽  
Computing Systems ◽  
Resolution Electron ◽  
Plane Group

A number of computing systems devoted to the averaging of electron images of two-dimensional macromolecular crystalline arrays have facilitated the visualization of negatively-stained biological structures. Either by simulation of optical filtering techniques or, in more refined treatments, by cross-correlation averaging, an idealized representation of the repeating asymmetric structure unit is constructed, eliminating image distortions due to radiation damage, stain irregularities and, in the latter approach, imperfections and distortions in the unit cell repeat. In these analyses it is generally assumed that the electron scattering from the thin negativelystained object is well-approximated by a phase object model. Even when absorption effects are considered (i.e. “amplitude contrast“), the expansion of the transmission function, q(x,y)=exp (iσɸ (x,y)), does not exceed the first (kinematical) term. Furthermore, in reconstruction of electron images, kinematical phases are applied to diffraction amplitudes and obey the constraints of the plane group symmetry.

Cell surface changes during aging of human bladder epithelium examined by lectin probes and SEM

1990 ◽  
Vol 48 (3) ◽  
pp. 966-967
Author(s):  
J. Jacob ◽  
M.F.M. Ismail
Keyword(s):  
The Elderly ◽  
Ultrastructural Changes ◽  
Pokeweed Mitogen ◽  
Asymmetric Structure ◽  
Luminal Surface ◽  
Bladder Epithelium ◽  
Aldehyde Groups ◽  
Cell Surface Changes ◽  
Phosphate Buffered Saline ◽  
Surface Changes

Ultrastructural changes have been shown to occur in the urinary bladder epithelium (urothelium) during the life span of humans. With increasing age, the luminal surface becomes more flexible and develops simple microvilli-like processes. Furthermore, the specialised asymmetric structure of the luminal plasma membrane is relatively more prominent in the young than in the elderly. The nature of the changes at the luminal surface is now explored by lectin-mediated adsorption visualised by scanning electron microscopy (SEM).Samples of young adult (21-31 y old) and elderly (58-82 y old) urothelia were fixed in buffered 2% glutaraldehyde for 10 m and washed with phosphate buffered saline (PBS) containing Ca++ and Mg++ at room temperature. They were incubated overnight at 4°C in 0.1 M ammonium chloride in PBS to block any remaining aldehyde groups. The samples were then allowed to stand in PBS at 37°C for 2 h before incubation at 37°C for 30 m with lectins. The lectins used were concanavalin A (Con A), wheat germ agglutinin (WGA), phytohaemagglutinin (PHA) and pokeweed mitogen (PWM) at a concentration of 500 mg/ml in PBS at pH 7.A.

Asymmetric-Structure-Induced Self-Rectifying in Nanoscale HfO2-Based RRAM Array

2019 ◽  
Vol 66 (8) ◽  
pp. 3337-3341 ◽  
Author(s):  
Xinlei Zhang ◽  
Hao Ji ◽  
Ran Jiang
Keyword(s):  
Asymmetric Structure

scholarly journals Efficacy of navigating through the intraplaque route using AnteOwl WR intravascular ultrasound in femoropopliteal chronic total occlusion

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Naoki Hayakawa ◽  
Satoshi Kodera ◽  
Keisuke Takanashi ◽  
Shuichi Sahashi ◽  
Sandeep Shakya ◽  
...  
Keyword(s):  
Intravascular Ultrasound ◽  
Popliteal Artery ◽  
Chronic Total Occlusion ◽  
Asymmetric Structure ◽  
Stent Deployment ◽  
Total Occlusion ◽  
Antegrade Approach ◽  
Angiographic Image ◽  
Good Expansion ◽  
Drug Coated Balloon

Abstract Background There is no consensus on the optimal guidewire passage route for femoropopliteal (FP) chronic total occlusion (CTO). If intraplaque wiring can be performed, a stent-less strategy using a drug-coated balloon can be realized even with FP CTO, and there is a high possibility that good expansion can be obtained even when stent deployment is performed. AnteOwl WR (AnteOwl) is a novel intravascular ultrasound (IVUS) device useful for navigating the second guidewire into the intraplaque route under IVUS observation from the subintimal space. Here, we describe representative cases of FP CTO in which CTO-specific IVUS was extremely useful. Case presentation Case 1 involved a 79-year-old man with total occlusion of the left superficial femoral artery (SFA). We used a contralateral antegrade approach, but the guidewire was advanced into the subintimal space. We advanced AnteOwl into the CTO. By utilizing the asymmetric structure of the transducer and the IVUS wire, we were able to reflect the positional relationship among the IVUS transducer, IVUS wire, and target plaque onto the angiographic image. By aiming the wiring in that direction, we succeeded in traversing the center of the plaque and finally succeeded in obtaining good expansion using the drug-coated balloon. Case 2 involved a 76-year-old woman with total occlusion from the SFA to the popliteal artery. We used an ipsilateral antegrade approach. When AnteOwl was placed on the wire and advanced to the popliteal artery, the subintimal space in the middle of the SFA could be visualized. We employed an IVUS-guided parallel wiring technique and succeeded in passing through all intraplaque routes. Although the CTO was long, we could easily advance through the intraplaque route by reflecting the information obtained from AnteOwl in angiography. Conclusions AnteOwl is an effective IVUS for FP CTO and facilitates a complex IVUS-guided procedure.

scholarly journals Membrane lymphotoxin-α2β is a novel tumor necrosis factor (TNF) receptor 2 (TNFR2) agonist

2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Kirstin Kucka ◽  
Isabell Lang ◽  
Tengyu Zhang ◽  
Daniela Siegmund ◽  
Juliane Medler ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Tumor Necrosis Factor ◽  
Tumor Necrosis ◽  
Asymmetric Structure ◽  
Tnf Receptor ◽  
Membrane Bound ◽  
Necrosis Factor

AbstractIn the early 1990s, it has been described that LTα and LTβ form LTα2β and LTαβ2 heterotrimers, which bind to TNFR1 and LTβR, respectively. Afterwards, the LTαβ2–LTβR system has been intensively studied while the LTα2β–TNFR1 interaction has been ignored to date, presumably due to the fact that at the time of identification of the LTα2β–TNFR1 interaction one knew already two ligands for TNFR1, namely TNF and LTα. Here, we show that LTα2β interacts not only with TNFR1 but also with TNFR2. We furthermore demonstrate that membrane-bound LTα2β (memLTα2β), despite its asymmetric structure, stimulates TNFR1 and TNFR2 signaling. Not surprising in view of its ability to interact with TNFR2, LTα2β is inhibited by Etanercept, which is approved for the treatment of rheumatoid arthritis and also inhibits TNF and LTα.

scholarly journals Double-asymmetric-structure 1.5 μ m high power laser diodes

2019 ◽  
Author(s):  
Lauri Hallman ◽  
Boris S. Ryvkin ◽  
Eugene A. Avrutin ◽  
Antti T. Aho ◽  
Jukka Viheriala ◽  
...  
Keyword(s):  
High Power ◽  
Laser Diodes ◽  
Asymmetric Structure ◽  
High Power Laser ◽  
Power Laser

scholarly journals Hydrophylicity Enhancement of Modified Cellulose Acetate Membrane to Improve the Membrane Performance in Produced Water Treatment

2018 ◽  
Vol 156 ◽  
pp. 08003 ◽  
Author(s):  
Tutuk Djoko Kusworo ◽  
Danny Soetrisnanto ◽  
Cynthia Santoso ◽  
Tyas Dwi Payanti ◽  
Dani Puji Utomo
Keyword(s):  
Water Treatment ◽  
Produced Water ◽  
Uv Light ◽  
Light Exposure ◽  
Membrane Surface ◽  
Asymmetric Structure ◽  
Dense Layer ◽  
Cellulose Acetate Membrane ◽  
Permeate Flux ◽  
Produced Water Treatment

Produced water is a wastewater generated from petroleum industry with high concentration of pollutants such as Total Dissolved Solid, Organic content, and Oil and grease. Membrane technology has been currently applied for produced water treatment due to its efficiency, compact, mild and clean process. The main problem of produced water using membrane is fouling on the membrane surface which causes on low permeate productivity. This paper is majority focused on the improvement of anti-fouling performance through several modifications to increase CA membrane hydrophilicity. The membrane was prepared by formulating the dope solution consists of 18 wt-% CA polymer, acetone, and PEG additive (3 wt-%, 5 wt-%, and 7 wt-%). The membranes are casted using NIPS method and being irradiated under UV light exposure. The SEM images show that parepared membrane has asymmetric structure consist of dense layer, intermediete layer, and finger-like support layer. The filtration test shows that PEG addition increase the membrane hydrophilicity and the permeate flux increases. UV light exposure on the membrane improves the membrane stability and hydrophilicity. The imrpovement of membrane anti-fouling performance is essential to achieve the higher productivity without lowering its pollutants rejection.

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