1,428 research outputs found
Stability Indicating LC-Method for Estimation of Paracetamol and Lornoxicam in Combined Dosage Form
A simple, specific and stability indicating reversed phase high performance liquid chromatographic method was developed for the simultaneous determination of paracetamol and lornoxicam in tablet dosage form. A Brownlee C-18, 5 μm column having 250×4.6 mm i.d. in isocratic mode, with mobile phase containing 0.05 M potassium dihydrogen phosphate:methanol (40:60, v/v) was used. The flow rate was 1.0 ml/min and effluents were monitored at 266 nm. The retention times of paracetamol and lornoxicam were 2.7 min and 5.1 min, respectively. The linearity for paracetamol and lornoxicam were in the range of 5–200 μg/ml and 0.08–20 μg/ml, respectively. Paracetamol and lornoxicam stock solutions were subjected to acid and alkali hydrolysis, chemical oxidation and dry heat degradation. The proposed method was validated and successfully applied to the estimation of paracetamol and lornoxicam in combined tablet dosage form
Towards the theory of ferrimagnetism
Two-sublattice ferrimagnet, with spin- operators at the
sublattice site and spin- operators at the sublattice
site, is considered. The magnon of the system, the transversal fluctuation
of the total magnetization, is a complicate mixture of the transversal
fluctuations of the sublattice and spins. As a result, the magnons'
fluctuations suppress in a different way the magnetic orders of the and
sublattices and one obtains two phases. At low temperature the
magnetic orders of the and spins contribute to the magnetization of the
system, while at the high temperature , the magnetic order of the
spins with a weaker intra-sublattice exchange is suppressed by magnon
fluctuations, and only the spins with stronger intra-sublattice exchange has
non-zero spontaneous magnetization. The transition is a transition
between two spin-ordered phases in contrast to the transition from spin-ordered
state to disordered state (-transition). There is no additional symmetry
breaking, and the Goldstone boson has a ferromagnetic dispersion in both
phases. A modified spin-wave theory is developed to describe the two phases.
All known Neel's anomalous curves are reproduced, in particular that
with "compensation point". The theoretical curves are compared with
experimental ones for sulpho-spinel and rare earth iron
garnets.Comment: 9 pages, 8 figure
Genetic Polymorphism in Evolving Population
We present a model for evolving population which maintains genetic
polymorphism. By introducing random mutation in the model population at a
constant rate, we observe that the population does not become extinct but
survives, keeping diversity in the gene pool under abrupt environmental
changes. The model provides reasonable estimates for the proportions of
polymorphic and heterozygous loci and for the mutation rate, as observed in
nature
Planar magnetic structures in coronal mass ejection-driven sheath regions
Planar magnetic structures (PMSs) are periods in the solar wind during which interplanetary magnetic field vectors are nearly parallel to a single plane. One of the specific regions where PMSs have been reported are coronal mass ejection (CME)-driven sheaths. We use here an automated method to identify PMSs in 95 CME sheath regions observed in situ by the Wind and ACE spacecraft between 1997 and 2015. The occurrence and location of the PMSs are related to various shock, sheath, and CME properties. We find that PMSs are ubiquitous in CME sheaths; 85% of the studied sheath regions had PMSs with the mean duration of 6 h. In about one-third of the cases the magnetic field vectors followed a single PMS plane that covered a significant part (at least 67%) of the sheath region. Our analysis gives strong support for two suggested PMS formation mechanisms: the amplification and alignment of solar wind discontinuities near the CME-driven shock and the draping of the magnetic field lines around the CME ejecta. For example, we found that the shock and PMS plane normals generally coincided for the events where the PMSs occurred near the shock (68% of the PMS plane normals near the shock were separated by less than 20 degrees from the shock normal), while deviations were clearly larger when PMSs occurred close to the ejecta leading edge. In addition, PMSs near the shock were generally associated with lower upstream plasma beta than the cases where PMSs occurred near the leading edge of the CME. We also demonstrate that the planar parts of the sheath contain a higher amount of strong southward magnetic field than the non-planar parts, suggesting that planar sheaths are more likely to drive magnetospheric activity.Peer reviewe
Inherited electrophoretic variants detected in a Japanese population with two-dimensional gels of erythrocyte lysates
Genetic variation has been studied in erythrocyte lysates from 100 Japanese children and their parents by means of two-dimensional polyacrylamide gel electrophoresis. Fifty-five polypeptides selected without respect to variability were considered suitable for scoring. Genetic variation was encountered in 14 of these polypeptides. Family data show that the segregation of 13 variants is consistent with an autosomal codominant mode of inheritance; the remaining variant exhibits a sex-linked mode of inheritance. Of 8 presumably identical polypeptides found variable in Japanese and/or Caucasians, differences in the occurrence or allele frequencies of polymorphisms were recognized for four. Contrary to the experience of some investigators, the amount of variation and the ethnic differences we are encountering indicate that two-dimensional polyacrylamide gel electrophoresis is a sensitive tool for the study of genetic events.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65555/1/j.1469-1809.1986.tb01753.x.pd
Objective response to immune checkpoint inhibitor therapy in NRAS-mutant melanoma: A systematic review and meta-analysis
INTRODUCTION:
METHODS: We performed a comprehensive literature search across several large databases. Inclusion criteria were trials, cohorts, and large case series that analyzed the primary outcome of objective response rate by
RESULTS: Data on 1770 patients from ten articles were pooled for meta-analysis, and the objective response rate to ICIs was calculated to compare
DISCUSSION: In this meta-analysis evaluating the impact o
The frequency in Japanese of genetic variants of 22 proteins
This paper presents the results of an electrophoretic survey of approximately 4000 individuals from the cities of Hiroshima and Nagasaki, Japan, for four serum proteins: albumin, ceruloplasmin, haptoglobin and transferrin. The haptoglobin gene frequencies obtained for the HP 1 -HP 2 polymorphism are in agreement with earlier reports. Rare electrophoretic variants of albumin, ceruloplasmin and haptoglobin occur with frequencies of 2.48, 0.50 and 0.58 per 1000 determinations, respectively. The noteworthy finding of 8 distinct transferrin variants in these populations, with a combined frequency of 20.90 per 1000 determinations, is also presented. Four of these variants (D Ch1 , B 1 , B 3 and D hir2 which corresponds electrophoretically to D 4 ) have been reported in other populations in Japan, but the other five have not previously been differentiated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66399/1/j.1469-1809.1977.tb01859.x.pd
A large new family of filled skutterudites stabilized by electron count
Based on the interplay of theory and experiment, a large new family of filled
group 9 (Co, Rh and Ir) skutterudites is designed and synthesized. The new
materials fill the empty cages in the structures of the known binary CoSb3,
RhSb3 and IrSb3 skutterudites with alkaline, alkaline earth, and rare earth
atoms to create compounds of the type AyB4X12; A atoms fill the cages to a
fraction y, B are the group 9 transition metals, and X is a mixture of
electronegative main group elements chosen to achieve chemical stability by
adjusting the electron counts to electron-precise values. Forty-three new
compounds are reported, antimony-tin and phosphorous-silicon based, with 63
compositional variations presented. The new family of compounds is large and
general. The results described here can be extended to the synthesis of
hundreds of new group 9 filled skutterudites.Comment: A revised version with the title"A large family of filled
skutterudites stabilized by electron count"will appear in Nature
Communication
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