Search results for "SoMe"
showing 10 items of 5114 documents
Zwitterionic codeine-derived methacrylate monoliths for enantioselective capillary electrochromatography of chiral acids and chiral bases
2018
Thiol-ene click reaction of N-acetyl-L-cysteine methyl ester to codeine, followed by reaction with allyl isocyanate and hydrolysis to the corresponding zwitterionic chiral selector and its subsequent bonding to the surface of a methacrylate monolith provided a new chiral capillary column for enantiomer separation of chiral acids and chiral bases. First, the epoxy groups of a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith were converted into amine residues, followed by reaction with allylglycidyl ether. In this way, a spacer arm was bonded to the surface before coating and cross-linking poly(3-mercaptopropyl methylsiloxane) (PMPMS) via radical addition (thiol-ene click react…
Reinvestigation of the Pd-catalysed bis(silylation) of alkynes with 1,1,2,2-tetramethyl-1,2-bis(phenylthiomethyl)disilane: Unexpected formation of th…
2013
International audience; The bis(silylated) alkenes Z-(PhSCH2)Me2SiC(H)=C(Fc)SiMe2(CH2SPh) (2) and Z-(PhSCH2)Me2SiC(H)=C(bipheny)SiMe2(CH2SPh) (3) have been prepared by Pd-catalysed double silylation of ethynylferrocene and 4-ethynyl-1,1'-biphenyl in the presence of 1,1,2,2-tetramethyl-1,2-bis(phenylthiomethyl)disilane (1). A reinvestigation on the interaction of 1 with [PdCl2(PhCN)2] in technical-grade CH2Cl2 as solvent revealed competition between reduction to elemental palladium (due to oxidative addition of the Si-Si bond across Pd(II) and subsequent reductive elimination) and formation of an unusual eight-membered chelate complex cis-[PdCl2{(PhSCH2SiMe2)2O}] (4), which is fluxional in s…
Triple-target stimuli-responsive anti-COVID-19 face mask with physiological virus-inactivating agents
2021
Conventional face masks to prevent SARS-CoV-2 transmission are mostly based on a passive filtration principle. Ideally, anti-COVID-19 masks should protect the carrier not only by size exclusion of virus aerosol particles, but also be able to capture and destroy or inactivate the virus. Here we present the proof-of-concept of a filter mat for such a mask, which actively attracts aerosol droplets and kills the virus. The electrospun mats are made of polycaprolactone (PCL) a hydrophilic, functionalizable and biodegradable polyester, into which inorganic polyphosphate (polyP) a physiological biocompatible, biodegradable and antivirally active polymer (chain length, ∼40 Pi units) has been integr…
Tetraspanin CD151 Mediates Papillomavirus Type 16 Endocytosis
2013
ABSTRACT Human papillomavirus type 16 (HPV16) is the primary etiologic agent for cervical cancer. The infectious entry of HPV16 into cells occurs via a so-far poorly characterized clathrin- and caveolin-independent endocytic pathway, which involves tetraspanin proteins and actin. In this study, we investigated the specific role of the tetraspanin CD151 in the early steps of HPV16 infection. We show that surface-bound HPV16 moves together with CD151 within the plane of the membrane before they cointernalize into endosomes. Depletion of endogenous CD151 did not affect binding of viral particles to cells but resulted in reduction of HPV16 endocytosis. HPV16 uptake is dependent on the C-termina…
RNAi mediated acute depletion of Retinoblastoma protein (pRb) promotes aneuploidy in human primary cells via micronuclei formation
2009
BACKGROUND: Changes in chromosome number or structure as well as supernumerary centrosomes and multipolar mitoses are commonly observed in human tumors. Thus, centrosome amplification and mitotic checkpoint dysfunctions are believed possible causes of chromosomal instability. The Retinoblastoma tumor suppressor (RB) participates in the regulation of synchrony between DNA synthesis and centrosome duplication and it is involved in transcription regulation of some mitotic genes. Primary human fibroblasts were transfected transiently with short interfering RNA (siRNA) specific for human pRb to investigate the effects of pRb acute loss on chromosomal stability. RESULTS: Acutely pRb-depleted fibr…
Identification and Characterization of Stress-Responsive TAS3-Derived TasiRNAs in Melon
2019
Small interfering RNAs (siRNA) are key regulators of gene expression that play essential roles in diverse biological processes. Trans-acting siRNAs (tasiRNAs) are a class of plant-endogenous siRNAs that lead the cleavage of non-identical transcripts. TasiRNAs are usually involved in fine-tuning development. However, increasing evidence supports that tasiRNAs may be involved in stress response. Melon is a crop of great economic importance extensively cultivated in semiarid regions frequently exposed to changing environmental conditions that limit its productivity. However, knowledge of the precise role of siRNAs in general, and of tasiRNAs in particular, in regulating the response to adverse…
Social media users’ online subjective well-being and fatigue: A network heterogeneity perspective
2021
Scholars have drawn increasing attention to the implications of the dark side of social media for users’ online subjective well-being (OSWB). We develop a research framework based on the limited-capacity model to examine the relationship between OSWB and social media fatigue. Moreover, we explore the associations between specific aspects related to network heterogeneity and social media fatigue for social media users in the United States of America (USA). Further, we examine the mediating effect of network heterogeneity on the association between OSWB and social media fatigue. We utilised a cross-sectional research design to collect data from Prolific Academic (N = 320) and analysed the dat…
The polarimetric and helioseismic imager on solar orbiter
2020
This paper describes the Polarimetric and Helioseismic Imager on the Solar Orbiter mission (SO/PHI), the first magnetograph and helioseismology instrument to observe the Sun from outside the Sun-Earth line. It is the key instrument meant to address the top-level science question: How does the solar dynamo work and drive connections between the Sun and the heliosphere? SO/PHI will also play an important role in answering the other top-level science questions of Solar Orbiter, as well as hosting the potential of a rich return in further science. SO/PHI measures the Zeeman effect and the Doppler shift in the FeI 617.3nm spectral line. To this end, the instrument carries out narrow-band imaging…
Influence of structure on the tissue dynamics of the human soleus muscle observed in MRI studies during isometric contractions.
2006
This article investigates how the internal structure of muscle and its relationship with tendon and even skeletal structures influence the translation of muscle fiber contractions into movement of a limb. Reconstructions of the anatomy of the human soleus muscle from the Visible Human Dataset (available from the National Library of Medicine), magnetic resonance images (MRI), and cadaver studies revealed a complex 3D connective tissue structure populated with pennate muscle fibers. The posterior aponeurosis and the median septum of the soleus form the insertion of the muscle and are continuous with the Achilles tendon. The distal extremities of the pennate muscle fibers attach to these struc…
Joined effects of pennation angle and tendon compliance on fibre length in isometric contractions: a simulation study.
1998
The main purpose of this study was to investigate the joined behaviours of tendon and pennation angle during maximal isometric contractions. A musculotendon model of the human soleus muscle was simulated as a function of ankle joint position, which determines the soleus length. Analysis of the respective values of tendon length and pennation angle for various musculotendon lengths showed that the primary effects of tendon elasticity and pennation angle variation were to reduce the fibre length variations by absorption of the musculotendon lengthening. The efficiency of this reduction process was the highest at short soleus lengths and principally related to tendon length variations. Finally…