Simple and efficient in situ generated copper nanocatalyst for stereoselective semihydrogenation of alkynes

2021 ◽  
Author(s):  
Byoung Yong Park ◽  
Taeho Lim ◽  
Min Su Han
Keyword(s):  
Practical Method ◽  
Organic Laboratory

Development of a simple, effective, and practical method for (Z)-selective semihydrogenation of alkynes have been considered necessary for easy-to-access applications in organic laboratory scales. Herein, (Z)-selective semihydrogenation of alkynes was...

Gold(I)-Catalyzed Rearrangement of Propargyl Benzyl Ethers: A Practical Method for the Generation and in Situ Transformation of Substituted Allenes

2010 ◽  
Vol 132 (21) ◽  
pp. 7294-7296 ◽  
Author(s):  
Benoit Bolte ◽  
Yann Odabachian ◽  
Fabien Gagosz
Keyword(s):  
Practical Method ◽  
Benzyl Ethers

scholarly journals Nanopore-mediated protein delivery enabling three-color single-molecule tracking in living cells

2021 ◽  
Vol 118 (5) ◽  
pp. e2012229118
Author(s):  
Zhongwen Chen ◽  
Yuhong Cao ◽  
Chun-Wei Lin ◽  
Steven Alvarez ◽  
Dongmyung Oh ◽  
...  
Keyword(s):  
Single Molecule ◽  
Protein Delivery ◽  
Chemical Properties ◽  
Practical Method ◽  
Living Cells ◽  
Egfr Signaling ◽  
Single Molecule Tracking ◽  
Ras Activation ◽  
And Chemical Properties

Multicolor single-molecule tracking (SMT) provides a powerful tool to mechanistically probe molecular interactions in living cells. However, because of the limitations in the optical and chemical properties of currently available fluorophores and the multiprotein labeling strategies, intracellular multicolor SMT remains challenging for general research studies. Here, we introduce a practical method employing a nanopore-electroporation (NanoEP) technique to deliver multiple organic dye-labeled proteins into living cells for imaging. It can be easily expanded to three channels in commercial microscopes or be combined with other in situ labeling methods. Utilizing NanoEP, we demonstrate three-color SMT for both cytosolic and membrane proteins. Specifically, we simultaneously monitored single-molecule events downstream of EGFR signaling pathways in living cells. The results provide detailed resolution of the spatial localization and dynamics of Grb2 and SOS recruitment to activated EGFR along with the resultant Ras activation.

scholarly journals Practical Method to Screen Contaminated Holograms of Flocs Using Light Intensity

2021 ◽  
Vol 8 ◽  
Author(s):  
Sun Min Choi ◽  
Jun Young Seo ◽  
Guan-hong Lee ◽  
Xiaoteng Shen ◽  
Ho Kyung Ha
Keyword(s):  
Light Intensity ◽  
Practical Method ◽  
Accurate Estimation ◽  
Cohesive Sediments ◽  
Degree Of Contamination ◽  
Particle Properties ◽  
And Behavior ◽  
Biological Organisms ◽  
Number Of Particles

Submergible digital holographic camera can measure the in situ size and shape of suspended particles, such as complex flocs and biological organisms, without disturbance. As the number of particles in the water column increases, overlapping concentric rings (interference patterns) can contaminate the holographic images. Using light intensity (LI), this study proposes a practical method to assess the degree of contamination and screen out contaminated images. The outcomes from image processing support that LI normalized on a gray scale of 0 (black) to 255 (white) can be a reliable criterion for defining the contamination boundary. Results found that as LI increased, the shape of the particle size distribution shifted from a positively skewed to a normal distribution. When LI was lower than approximately 80, owing to the distortion of particle properties, the settling velocities derived from the contaminated holograms with mosaic patterns were underestimated compared to those from the uncontaminated holograms. The proposed method can contribute to a more accurate estimation of the transport and behavior of cohesive sediments in shallow estuarine environments.

Catalyst-free formation of 1,4-diketones by addition of silyl enolates to oxyallyl zwitterions in situ generated from α-haloketones

RSC Advances ◽  
2015 ◽  
Vol 5 (83) ◽  
pp. 67901-67908 ◽  
Author(s):  
Juan Luo ◽  
Qihua Jiang ◽  
Hao Chen ◽  
Qiang Tang
Keyword(s):  
Room Temperature ◽  
Practical Method ◽  
Direct Coupling ◽  
Catalyst Free

Here we report an efficient and practical method for the preparation of 1,4-diketones by direct coupling of α-haloketones with silyl enolates at room temperature. No catalysts were required in our protocol.

scholarly journals In Situ Electrophilic Activation of Hydrogen Peroxide for Catalytic Asymmetric α-Hydroxylation of 3-Substituted Oxindoles

Synlett ◽  
2017 ◽  
Vol 28 (11) ◽  
pp. 1291-1294 ◽  
Author(s):  
Takashi Ooi ◽  
Kohsuke Ohmatsu ◽  
Yuichiro Ando
Keyword(s):  
Hydrogen Peroxide ◽  
Phase Transfer ◽  
Practical Method ◽  
Optically Active ◽  
Aqueous Hydrogen Peroxide ◽  
Bond Forming ◽  
Electrophilic Activation ◽  
Oxygen Bond ◽  
Activation Of Hydrogen Peroxide

Peroxy trichloroacetimidic acid, in situ generated from aqueous hydrogen peroxide and trichloroacetonitrile, was found to act as a competent electrophilic oxygenating agent for the direct α-hydroxylation of oxindoles. The use of chiral 1,2,3-triazolium salt as a phase-transfer catalyst enabled rigorous absolute stereocontrol in the carbon–oxygen bond-forming reaction. The present study provides a new, yet practical method for straightforward access to optically active α-hydroxycarbonyl compounds.

scholarly journals An Approach for In Situ Rapid Detection of Deep-Sea Aromatic Amino Acids Using Laser-Induced Fluorescence

Sensors ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 1330
Author(s):  
Ranran Du ◽  
Dingtian Yang ◽  
Guangjia Jiang ◽  
Youren Song ◽  
Xiaoqing Yin
Keyword(s):  
Amino Acids ◽  
Deep Sea ◽  
Rapid Detection ◽  
Aromatic Amino Acids ◽  
Practical Method ◽  
Laser Induced Fluorescence ◽  
Carbon Cycles ◽  
Material Circulation ◽  
Almost All

Amino acids are the material basis of almost all life activities. An improved understanding of the source, state, and cycle of amino acids is essential for determining the energy flow and material circulation of marine ecosystems. In the present study, an in situ rapid detection method of ultraviolet (UV; 266 nm) laser-induced fluorescence (LIF) technology was used to detect three natural, aromatic amino acids in the seawater. The laser-induced fluorescence peaks of aromatic amino acids tryptophan, tyrosine, and phenylalanine were located at 350 nm, 300 nm, and 280 nm, respectively. High, linear correlations between the concentrations of the aromatic amino acids and the fluorescence peak heights were observed, and the lowest detectable concentrations of tryptophan, tyrosine, and phenylalanine were 4.70 × 10−9 mol/L, 2.76 × 10−8 mol/L, and 6.05 × 10−7 mol/L, respectively, which allowed us to quantify their concentrations by using laser-induced fluorescence. This paper not only provides a practical method for the detection of aromatic amino acids in seawater, but a new means to further understand the biogeochemical processes of carbon cycles in the deep sea.

scholarly journals Under Pressure: Comparing Fish Survivorship Between in Situ and Boat Tagging Methods Using Internal Acoustic Tags

2020 ◽  
Author(s):  
Jessica A. Keller ◽  
Danielle Morley ◽  
Jennifer Herbig ◽  
Paul Barbera ◽  
Michael W. Feeley ◽  
...  
Keyword(s):  
Survival Probability ◽  
Proportional Hazards ◽  
Handling Time ◽  
Practical Method ◽  
Cox Proportional Hazards ◽  
Cox Proportional Hazards Models ◽  
Acoustic Tags ◽  
Tagging Methods ◽  
Acoustic Tagging

Abstract Background: With the increase in telemetry studies over the past decade, improving understanding of how different tagging methods influence fish survivorship is critical. By examining the effects of tagging methods, we can maximize the information gained from telemetry studies. Mortality resulting from internally tagging fish on a boat may be due to barotrauma injuries, increased stress from prolonged handling times, or predation after fish have been released back into the water. Conducting in situ internal acoustic tagging at depth of capture completely removes barotrauma stresses and simplifies the release method, which may improve fish survival. In this study, we used 8 years of acoustic tagging data to determine if the tagging method (in situ versus on the boat) influenced fish survivorship and evaluated the role of other tagging variables.Results: At 6 days after tagging, Kaplan–Meier survival curves revealed that the survival probability of fish tagged on the boat was 66% while survival probability of fish tagged in situ was 90%. Tagging method was the only variable to significantly affect survival probability based on Cox proportional hazards models, with fish tagged in situ ~75% less likely to have an “event” (mortality, tag loss, or emigration) compared to fish tagged on the boat at both 4 and 6 days after tagging. Examining tagging methods separately, handling time only marginally influenced survival probability of boat-tagged fish and no variables had a significant effect on survival of in situ tagged fish. Conclusions: In this study, tagging method was the only variable to significantly affect survival of internally tagged fish. Implanting internal acoustic tags in situ is not a practical method for every species and for every environment, but given the increased fish survivorship demonstrated here, we strongly suggest it be considered as the preferred tagging methodology where applicable.

Sign in / Sign up

Export Citation Format

Share Document