1,509 research outputs found
Formulasi Sediaan Granul Mukoadhesif Kombinasi Ekstrak Kulit Batang Mimba (Azadirachta Indica a. Juss) Dan Kunyit (Curcuma Domestica Val.)
Neem bark (Azadirachta indica A.Juss) and turmeric (Curcuma domestica Val.) extracts have been found posses gastroprotective effect so that they are used in the treatment of gastric ulcer. Administration of combination of both extracts can give synergistic effect so that the administration dose can be reduced. In this research, combination of neem bark and turmeric extracts were formulated as mucoadhesive granules to improve their effectivenesses by increasing the residence time of dosage form in the stomach. Mucoadhesive granuleswere prepared by wet granulation method in six formulas using HPMC, Carbopol, and combination of HPMC and Carbopol as mucoadhesive polymers. Granules were evaluated for particle size distribution, swelling, mucoadhesive strength with bioadhesive in vitro test and wash off test, and dissolution. Bioadhesive in vitro test showed that all formulas have goodmucoadhesive strength.Wash off test showed that combination of HPMC and Carbopol can improve mucoadhesive strength of formulas. Mucoadhesive strength increased with the increasing of HPMC. The result of this research indicated that formula with combination ofHPMCand Carbopol (2:1) showed best mucoadhesive strength with percentage of mucoadhesion 98.67%in bioadhesive in vitro test and 38.00% in wash off test
Correlation of conductivity and angle integrated valence band photoemission characteristics in single crystal iron perovskites for 300 K < T < 800 K: Comparison of surface and bulk sensitive methods
A single crystal monolith of La0.9Sr0.1FeO3 and thin pulsed laser deposited
film of La0.8Sr0.2Fe0.8Ni0.2O3 were subject to angle integrated valence band
photoemission spectroscopy in ultra high vacuum and conductivity experiments in
ambient air at temperatures from 300 K to 800 K. Except for several sputtering
and annealing cycles, the specimen were not prepared in-situ.. Peculiar changes
in the temperature dependent, bulk representative conductivity profile as a
result of reversible phase transitions, and irreversible chemical changes are
semi-quantitatively reflected by the intensity variation in the more surface
representative valence band spectra near the Fermi energy. X-ray photoelectron
diffraction images reflect the symmetry as expected from bulk iron perovskites.
The correlation of spectral details in the valence band photoemission spectra
(VB PES) and details of the conductivity during temperature variation suggest
that valuable information on electronic structure and transport properties of
complex materials may be obtained without in-situ preparation
Direct Observation of High-Temperature Polaronic Behavior In Colossal Magnetoresistive Manganites
The temperature dependence of the electronic and atomic structure of the
colossal magnetoresistive oxides (x = 0.3, 0.4) has
been studied using core and valence level photoemission, x-ray absorption and
emission, and extended x-ray absorption fine structure spectroscopy. A dramatic
and reversible change of the electronic structure is observed on crossing the
Curie temperature, including charge localization and spin moment increase of
Mn, together with Jahn-Teller distortions, both signatures of polaron
formation. Our data are also consistent with a phase-separation scenario.Comment: 5 pages, 4 figures, revte
Managing Risk of Bidding in Display Advertising
In this paper, we deal with the uncertainty of bidding for display
advertising. Similar to the financial market trading, real-time bidding (RTB)
based display advertising employs an auction mechanism to automate the
impression level media buying; and running a campaign is no different than an
investment of acquiring new customers in return for obtaining additional
converted sales. Thus, how to optimally bid on an ad impression to drive the
profit and return-on-investment becomes essential. However, the large
randomness of the user behaviors and the cost uncertainty caused by the auction
competition may result in a significant risk from the campaign performance
estimation. In this paper, we explicitly model the uncertainty of user
click-through rate estimation and auction competition to capture the risk. We
borrow an idea from finance and derive the value at risk for each ad display
opportunity. Our formulation results in two risk-aware bidding strategies that
penalize risky ad impressions and focus more on the ones with higher expected
return and lower risk. The empirical study on real-world data demonstrates the
effectiveness of our proposed risk-aware bidding strategies: yielding profit
gains of 15.4% in offline experiments and up to 17.5% in an online A/B test on
a commercial RTB platform over the widely applied bidding strategies
Thermal expansion and magnetostriction of pure and doped RAgSb2 (R = Y, Sm, La) single crystals
Data on temperature-dependent, anisotropic thermal expansion in pure and
doped RAgSb2 (R = Y, Sm, La) single crystals are presented. Using the Ehrenfest
relation and heat capacity measurements, uniaxial pressure derivatives for long
range magnetic ordering and charge density wave transition temperatures are
evaluated and compared with the results of the direct measurements under
hydrostatic pressure. In-plane and c-axis pressure have opposite effect on the
phase transitions in these materials, with in-plane effects being significantly
weaker. Quantum oscillations in magnetostriction were observed for the three
pure compounds, with the possible detection of new frequencies in SmAgSb2 and
LaAgSb2. The uniaxial (along the c-axis) pressure derivatives of the dominant
extreme orbits (beta) were evaluated for YAgSb2 and LaAgSb2
Recommended from our members
Polymer protected gold nanoparticles: synthesis, characterization and application in catalysis
This review discusses the stabilization of gold nanoparticles (AuNPs) by nonionic, anionic, cationic and amphoteric polymers. The protocols used for synthesis of AuNPs in aqueous and organic solvents are described. Size, shape and morphology of AuNPs are characterized by various physicochemical methods. Application aspects of polymer-protected AuNPs in catalysis are outlined
Elastic constants of borocarbides. New approach to acoustic Measurement technique
A new version of the phase method of determining the sound velocity is
proposed and implemented. It utilizes the ``Nonius'' measurement technique and
can give acceptable accuracy (~1%) in samples of submillimeter size.
Measurements of the sound velocity are made in single-crystal samples of the
borocarbides RNi2B2C (R = Y,Lu,Ho). The elastic constants and the Debye
temperature are calculated.Comment: 5 figures, 2 table
Missed prediction of the neutron halo in Mg
Halo phenomena have long been an important frontier in both experimental and
theoretical nuclear physics. Mg was identified as a halo nucleus in 2014
and remains the heaviest nuclear halo system to date. While the halo phenomenon
in Mg was not predicted before the discovery, its description has been
still challenging afterwards. In this Letter, we report a microscopic,
self-consistent, and density-functional independent description of the neutron
halo in Mg by the deformed relativistic Hartree-Bogoliubov theory in
continuum (DRHBc) that was developed in 2010. The experimental neutron
separation energies and empirical matter radii of neutron-rich magnesium
isotopes as well as the deformed -wave halo characteristics of Mg are
well reproduced without any free parameters. The DRHBc theory investigated only
even-even magnesium isotopes in previous works and for that reason missed
predicting Mg as a halo nucleus before 2014. Although the core and the
halo of Mg are both prolate, higher-order shape decoupling on the
hexadecapole and hexacontatetrapole levels is predicted.Comment: 8 pages, 4 figures, 1 tabl
Fragile antiferromagnetism in the heavy-fermion compound YbBiPt
We report results from neutron scattering experiments on single crystals of
YbBiPt that demonstrate antiferromagnetic order characterized by a propagation
vector, = (), and
ordered moments that align along the [1 1 1] direction of the cubic unit cell.
We describe the scattering in terms of a two-Gaussian peak fit, which consists
of a narrower component that appears below K and
corresponds to a magnetic correlation length of 80
, and a broad component that persists up to 0.7 K and
corresponds to antiferromagnetic correlations extending over 20 . Our results illustrate the fragile magnetic order
present in YbBiPt and provide a path forward for microscopic investigations of
the ground states and fluctuations associated with the purported quantum
critical point in this heavy-fermion compound.Comment: 5 pages, 3 figure
- …