Chitosan extracted from shrimp cortex was grafted with some different anhydride compounds like; acetic anhydride, propionic anhydride, succinic anhydride, and phthalic anhydride. The ...chitosan-grafted-anhydrides were copolymerized with L-lactide in ring opening polymerization. All grafted chitosan derivatives were obtained in very good yield, and they were characterized by FTIR and the resulted spectra confirmed the right structures of chitosan and its different synthesized derivatives, and then they were converted to nanoparticles in size by subjecting them to sonication method.In vitro cytotoxicity detection of different chitosan anhydride derivative nanoparticles and their grafted-polylactide were concerning three different types of human breast cancer cell lines as MTT assay, the results exhibit the highly significant cell growth inhibition of these tumor cells compared with a positive control; furthermore, the chitosan anhydride derivatives grafted polylactide demonstrated increasing in reducing cell viability in comparison with their non-grafted form. The DNA fragmentation index percentage was evaluated for some of the studied polymer nanoparticles, using acridine orange dye and the results were shown no or less effective against BT breast carcinoma cell lines DNA
The TOTEM modular trigger system Bagliesi, M.G.; Berretti, M.; Cecchi, R. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2010, Letnik:
617, Številka:
1
Journal Article
Recenzirano
The TOTEM experiment will measure the total cross-section with the luminosity independent method and study elastic and diffractive scattering at the LHC. We are developing a modular trigger system, ...based on programmable logic, that will select meaningful events within
2.5
μ
s
. The trigger algorithm is based on a tree structure in order to obtain information compression. The trigger primitive is generated directly on the readout chip, VFAT, that has a specific fast output that gives low resolution hits information. In two of the TOTEM detectors, Roman Pots and T2, a coincidence chip will perform track recognition directly on the detector readout boards, while for T1 the hits are transferred from the VFATs to the trigger hardware. Starting from more than 2000 bits delivered by the detector electronics, we extract, in a first step, six trigger patterns of 32 LVDS signals each; we build, then, on a dedicated board, a 1-bit (L1) trigger signal for the TOTEM experiment and 16 trigger bits to the CMS experiment global trigger system for future common data taking.
Shallow foundations are usually built above the groundwater table. In such cases, this soil is considered dry in analysis and design, while it is actually an unsaturated soil. This unsaturated soil ...can lead to many geotechnical issues, such as swelling when wet and collapsing when dry. It can also change the soil’s shear strength, which in turn affects the bearing capacity of the soil. The classical principles of saturated soil are often not suitable for explaining these phenomena. Limited studies dealt with a large scale model close to the field conditions for such soil and therefore, there is much more room for improvement. The study reveals that compacting the expansive soil on the wet side of optimum is capable of reducing swelling pressure and the expansion index for both the bentonite–sand mixture and kaolin soil. The bearing capacity of a footing resting on both swelling and non-swelling soils decreases noticeably with the increase in the soil degree of saturation due to the effect of matric suction which increases the soil stiffness. The results show that the measured bearing capacity is (1.1–3.3) higher than that estimated by Terzaghi equations.
Antacids have been widely used in the treatment of various gastric and duodenal disorders such as heartburn, reflux esophagitis, gastritis, irritable stomach, gastric and duodenal ulcers. A ...pH-responsive of bi-polymer of sodium alginate and pectin have been studied as raft-forming polymers using sodium bicarbonate and calcium carbonate as gas-generating and calcium ion sources. The aim of study was to formulate and evaluate mono and bilayer tablets of floating and sustained release antacid delivery systems using sodium carboxy methyl cellulose as a gel forming substance, calcium and magnesium carbonate as sources of acid neutralizing and carbon dioxide gas generators agents upon contact with acidic solution. The effect of the formulation contents on the buoyancy has been investigated. In addition to, the antacid activities of intact and pulverized tablets have been studied. The result obtained showed that the buoyance is remarkably affected by the percentages of sodium carboxy methyl cellulose and carbonates salts. All formulas of mono and bilayer tablets revealed sustained action of acid neutralization and raft formation. Besides, bilayer tablets showed a significant and higher level of acid neutralizing capacity than monolayer tablets. Moreover, the pulverized of bilayer tablets exhibited significant and higher acid neutralizing capacity at raft than that at bulk of artificial gastric juice medium.
Keywords: Raft forming agent, Antacid, floating drug delivery, Acid neutralizing capacity, Sodium carboxy methyl cellulose.
The TOTEM collaboration has measured the proton–proton total cross section at
s
=
13
TeV
with a luminosity-independent method. Using dedicated
β
∗
=
90
m
beam optics, the Roman Pots were inserted ...very close to the beam. The inelastic scattering rate has been measured by the T1 and T2 telescopes during the same LHC fill. After applying the optical theorem the total proton–proton cross section is
σ
tot
=
(
110.6
±
3.4
) mb, well in agreement with the extrapolation from lower energies. This method also allows one to derive the luminosity-independent elastic and inelastic cross sections:
σ
el
=
(
31.0
±
1.7
)
mb
and
σ
inel
=
(
79.5
±
1.8
)
mb
.
The TOTEM experiment at the LHC has performed the first measurement at
s
=
13
TeV
of the
ρ
parameter, the real to imaginary ratio of the nuclear elastic scattering amplitude at
t
=
0
, obtaining the ...following results:
ρ
=
0.09
±
0.01
and
ρ
=
0.10
±
0.01
, depending on different physics assumptions and mathematical modelling. The unprecedented precision of the
ρ
measurement, combined with the TOTEM total cross-section measurements in an energy range larger than
10
TeV
(from 2.76 to
13
TeV
), has implied the exclusion of all the models classified and published by COMPETE. The
ρ
results obtained by TOTEM are compatible with the predictions, from other theoretical models both in the Regge-like framework and in the QCD framework, of a crossing-odd colourless 3-gluon compound state exchange in the
t
-channel of the proton–proton elastic scattering. On the contrary, if shown that the crossing-odd 3-gluon compound state
t
-channel exchange is not of importance for the description of elastic scattering, the
ρ
value determined by TOTEM would represent a first evidence of a slowing down of the total cross-section growth at higher energies. The very low-|
t
| reach allowed also to determine the absolute normalisation using the Coulomb amplitude for the first time at the LHC and obtain a new total proton–proton cross-section measurement
σ
tot
=
(
110.3
±
3.5
)
mb
, completely independent from the previous TOTEM determination. Combining the two TOTEM results yields
σ
tot
=
(
110.5
±
2.4
)
mb
.
The TOTEM collaboration has measured the elastic proton-proton differential cross section
d
σ
/
d
t
at
s
=
13
TeV LHC energy using dedicated
β
∗
=
90
m beam optics. The Roman Pot detectors were ...inserted to 10
σ
distance from the LHC beam, which allowed the measurement of the range 0.04 GeV
2
; 4 GeV
2
in four-momentum transfer squared |
t
|. The efficient data acquisition allowed to collect about 10
9
elastic events to precisely measure the differential cross-section including the diffractive minimum (dip), the subsequent maximum (bump) and the large-|
t
| tail. The average nuclear slope has been found to be
B
=
(
20.40
±
0
.
002
stat
±
0
.
01
syst
)
GeV
-
2
in the |
t
|-range 0.04–0.2 GeV
2
. The dip position is
|
t
dip
|
=
(
0.47
±
0
.
004
stat
±
0
.
01
syst
)
GeV
2
. The differential cross section ratio at the bump vs. at the dip
R
=
1.77
±
0
.
01
stat
has been measured with high precision. The series of TOTEM elastic pp measurements show that the dip is a permanent feature of the pp differential cross-section at the TeV scale.
The TOTEM experiment at the CERN LHC has measured elastic proton–proton scattering at the centre-of-mass energy
s
=
8
TeV and four-momentum transfers squared, |
t
|, from
6
×
10
-
4
to 0.2 GeV
2
. ...Near the lower end of the
t
-interval the differential cross-section is sensitive to the interference between the hadronic and the electromagnetic scattering amplitudes. This article presents the elastic cross-section measurement and the constraints it imposes on the functional forms of the modulus and phase of the hadronic elastic amplitude. The data exclude the traditional Simplified West and Yennie interference formula that requires a constant phase and a purely exponential modulus of the hadronic amplitude. For parametrisations of the hadronic modulus with second- or third-order polynomials in the exponent, the data are compatible with hadronic phase functions giving either central or peripheral behaviour in the impact parameter picture of elastic scattering. In both cases, the
ρ
-parameter is found to be
0.12
±
0.03
. The results for the total hadronic cross-section are
σ
tot
=
(
102.9
±
2.3
)
mb and
(
103.0
±
2.3
)
mb for central and peripheral phase formulations, respectively. Both are consistent with previous TOTEM measurements.
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