107 research outputs found
A practical review on the measurement tools for cellular adhesion force
Cell cell and cell matrix adhesions are fundamental in all multicellular
organisms. They play a key role in cellular growth, differentiation, pattern
formation and migration. Cell-cell adhesion is substantial in the immune
response, pathogen host interactions, and tumor development. The success of
tissue engineering and stem cell implantations strongly depends on the fine
control of live cell adhesion on the surface of natural or biomimetic
scaffolds. Therefore, the quantitative and precise measurement of the adhesion
strength of living cells is critical, not only in basic research but in modern
technologies, too. Several techniques have been developed or are under
development to quantify cell adhesion. All of them have their pros and cons,
which has to be carefully considered before the experiments and interpretation
of the recorded data. Current review provides a guide to choose the appropriate
technique to answer a specific biological question or to complete a biomedical
test by measuring cell adhesion
QCD thermodynamics with continuum extrapolated Wilson fermions II
We continue our investigation of 2+1 flavor QCD thermodynamics using
dynamical Wilson fermions in the fixed scale approach. Two additional pion
masses, approximately 440 MeV and 285 MeV, are added to our previous work at
545 MeV. The simulations were performed at 3 or 4 lattice spacings at each pion
mass. The renormalized chiral condensate, strange quark number susceptibility
and Polyakov loop is obtained as a function of the temperature and we observe a
decrease in the light chiral pseudo-critical temperature as the pion mass is
lowered while the pseudo-critical temperature associated with the strange quark
number susceptibility or the Polyakov loop is only mildly sensitive to the pion
mass. These findings are in agreement with previous continuum results obtained
in the staggered formulation.Comment: 19 pages, 13 figures, published versio
Characterization of the dissolution of water microdroplets in oil
Water in oil emulsions have a wide range of applications from chemical
technology to microfluidics, where the stability of water droplets is of
paramount importance. Here using an accessible and easily reproducible
experimental setup we describe and characterize the dissolution of water in
oil, which renders nanoliter-sized droplets unstable, resulting in their
shrinkage and disappearance in a time scale of hours. This process has
applicability in creating miniature reactors for crystallization. We test
multiple oils and their combinations with surfactants exhibiting widely
different rates of dissolution. We derived simple analytical equations to
determine the product of the diffusion coefficient and the relative saturation
density of water in oil from the measured dissolution data. By measuring the
moisture content of mineral and silicone oils with Karl Fischer titration
before and after saturating them with water, we calculated the diffusion
coefficient of water in these two oilsComment: 8 pages 6 figures 3 supplementary video
Charmonium spectral functions from 2+1 flavour lattice QCD
Finite temperature charmonium spectral functions in the pseudoscalar and
vector channels are studied in lattice QCD with 2+1 flavours of dynamical
Wilson quarks, on fine isotropic lattices (with a lattice spacing of 0.057 fm),
with a non-physical pion mass of 545 MeV. The highest
temperature studied is approximately . Up to this temperature no
significant variation of the spectral function is seen in the pseudoscalar
channel. The vector channel shows some temperature dependence, which seems to
be consistent with a temperature dependent low frequency peak related to heavy
quark transport, plus a temperature independent term at \omega>0. These results
are in accord with previous calculations using the quenched approximation.Comment: 17 pages, 9 figures, 2 table
Electrochemical migration of Cu and Sn in Na2SO4 environment
The effect of Na2SO4 concentration on electrochemical migration (ECM) of copper and tin was investigated applying an in-situ optical and real-time electrical inspection system. According to the Mean-Time-To-Failure (MTTF) values, the ECM susceptibility of copper has increased at low concentration levels. However, the ECM susceptibility of copper has decreased at the medium and stopped at the high and even saturated concentration levels. On the other hand, the ECM susceptibility of tin has increased at low levels. Afterwards the ECM ability of tin was hindered and even stopped at medium level. Interestingly, the ECM susceptibility of tin was reappeared at high concentration levels
Determination of 24 primary aromatic amines in aqueous food simulants by combining solid phase extraction and salting-out assisted liquid?liquid extraction with liquid chromatography tandem mass spectrometry
Carcinogenic primary aromatic amines (PAAs) can be released from improperly manufactured food packaging materials. The limit for the sum of PAAs is set to 10 ?gkg- 1 in Commission Regulation No. 10/2011 (FCM Regulation). However, a lower individual limit, 2 ?gkg- 1 has been recently introduced for the carcinogenic PAAs in Commission Regulation No. 2020/1245. As the majority of the previously published methods are no longer compliant with the current regulation, a UHPLC-MS/MS method was developed to enable food packaging compliance testing for PAAs not only from 3% (w/v) acetic acid, but also from 10% (v/v) ethanol food simulant. Since the latest amendment of the FCM Regulation refers to the list of the 22 restricted PAAs of EU Regulation No. 1907/2006, these PAAs were selected as target compounds along with aniline and p-toluidine, the most common impurities of azo colorants and isocyanates. An enrichment factor of 20 could be achieved combining solid phase extraction with salting-out assisted liquid?liquid extraction. The method was successfully validated and applied on real samples. Limit of quantitation (LOQ) and limit of detection (LOD) values were 0.15 ?gL-1 and 0.05 ?gL-1 for both food simulants, respectively; except for 2,4-diaminotoluene, aniline and 4,4?-oxydianiline. However, even these compounds had lower LOD values than the new individual limit of 2 ?gkg- 1. Cumulative LOD values for both food simulants (1.6 ?gL-1 and 1.5 ?gL-1 for 3% (w/v) acetic acid and 10% (v/v) ethanol, respectively) were lower than the 10 ?gkg- 1 specified in the FCM Regulation. Accuracy values were between 70 and 118% for both food simulants for the majority of PAAs. Both within-day and between-day precision values were below 20%. This method proved to be suitable for daily routine analysis enabling compliance testing of food packaging materials according to the latest regulations. The method was successfully applied for the analysis of plastic kitchenware samples
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