Inequalities for the overpartition function

The Ramanujan Journal - Let $$\overline{p}(n)$$ denote the overpartition function. Engel showed that for $$n\ge 2$$ , $$\overline{p}(n)$$ satisfy the Turán inequalities, that is,...     

New Cell Growth-Inhibitory Cyclohexadienone Derivatives from Hypericum calycinum L.

The crude petroleum-ether extract of the aerial parts of Hypericum calycinum L. (Guttiferae) exhibited in vitro growth-inhibitory activity against the Co-115 human colon carcinoma cell line. Bioassay-guided fractionation of this extract allowed the isolation of the cyclohexadienone derivatives 1–5 , four of which are previously undescribed compounds. The structures of the known chinesin II (1) and of 2 (hypercalin A) were established by ¹H- and ¹³C-NMR spectroscopy and were confirmed by X-ray analysis of their crystalline mixture which revealed the complete relative configuration of both compounds. The structure of 3 (hypercalin B) was elucidated by means of extensive 1D- and 2D-NMR experiments, including DQ-COSY, HETCOR and LR-HETCOR. The structure of compound 4 (hypercalin C) was established by ¹H- and ¹³C-NMR spectroscopy and confirmed by X-ray analysis to be the 3,5-dihydroxy-4-{[(1R*,2S*, 5S*)-2-hydroxy-2-methyl-5-(1-methylethenyl)cyclopentyl]methyl}-6,6-bis-(3-methylbut-2-enyl)-2-(2-methylpropanoyl)cyclohexa-2,4-dien-1-one. The structures of the higher isomeric homologues 5a/5b were deduced by comparison of their UV, ¹H-, and ¹³C-NMR spectra with those of 4 . The isolated compounds appeared to be related to chinesin I and II previously isolated from Hypericum chinense L. and were responsible for the growth-inhibitory activity of the extract against the Co-115 human carcinoma cell line. Moreover, 1/2 and 3 showed molluscicidal activity against the schistosomiasis-transmitting snail Biomphalaria glabrata.     

Synthetic methods for polyamine linkers and their application to combinatorial chemistry

Summary Polyamines and polyamine conjugates display a diverse range of important biological functions, ranging from antibiotics to immunosuppressants and glutamate receptor antagonists. For these reasons, polyamines provide an excellent template/scaffold for combinatorial chemistry. In this paper we present methods for the solid-phase immobilisation of polyamines for use in synthetic and combinatorial chemistry and describe how they have been employed in the preparation of a number of important polyamine conjugates and polyamine libraries. Thus, we have designed, synthesised and utilised a number of polyamine linkers for both solution and resin screening combinatorial application.     

An inter-comparison of far-infrared line-by-line radiative transfer models

A considerable fraction (>40%) of the outgoing longwave radiation escapes from the Earth's atmosphere-surface system within a region of the spectrum known as the far-infrared (wave-numbers less than 650 cm⁻¹). Dominated by the line and continuum spectral features of the pure rotation band of water vapor, the far-infrared has a strong influence upon the radiative balance of the troposphere, and hence upon the climate of the Earth. Despite the importance of the far-infrared contribution, however, very few spectrally resolved observations have been made of the atmosphere for wave-numbers less than 650 cm⁻¹. The National Aeronautics and Space Administration (NASA), under its Instrument Incubator Program (IIP), is currently developing technology that will enable routine, space-based spectral measurements of the far-infrared. As part of NASA's IIP, the Far-Infrared Spectroscopy of the Troposphere (FIRST) project is developing an instrument that will have the capability of measuring the spectrum over the range from 100 to 1000 cm⁻¹ at a resolution of 0.6 cm⁻¹. To properly analyze the data from the FIRST instrument, accurate radiative transfer models will be required. Unlike the mid-infrared, however, no inter-comparison of codes has been performed for the far-infrared. Thus, in parallel with the development of the FIRST instrument, an investigation has been undertaken to inter-compare radiative transfer models for potential use in the analysis of far-infrared measurements. The initial phase of this investigation has focused upon the inter-comparison of six distinct line-by-line models. The results from this study have demonstrated remarkably good agreement among the models, with differences being of order 0.5%, thereby providing a high measure of confidence in our ability to accurately compute spectral radiances in the far-infrared.     

Syntheses,characterization, and biological evaluation of new zinc-and gold-chloroquine diphosphate complexes

Antimalarial drugs such as chloroquine are beneficial agents in systemic lupus and rheumatoid arthritis. In this work, two new chloroquine diphosphate (CQDP) complexes containing Zn(II) and Au(III) of formula Zn(CQDP)(NO₃)₂ (1) and Au(CQDP)Cl₃ (2), respectively, were synthesized and characterized by physico-chemical and spectroscopic methods. To examine their possible anti-inflammatory properties, the new derivatives were tested in the range from 1 to 100 μM on the respiratory burst of isolated human neutrophils (PMNs) as well as in whole blood. In isolated PMNs, complex 1 inhibited the isoluminol-enhanced chemiluminescence (IL-CL) only at the highest concentration tested, whereas in the whole blood assay, 10 μM of this complex was sufficient to significantly inhibit the luminol-enhanced chemiluminescence (L-CL). On the contrary, complex 2 dose-dependently inhibited the IL-CL but affected the L-CL only at 100 μM. In conclusion, both complexes are more active than CQDP and may be useful for future treatment of diseases resulting from exacerbated neutrophil functions.     

Gas Supply and Storage Planning: A Simulation Approach

This paper describes the problems faced by a region of British Gas in forecasting daily gas demand and gas storage requirements. The discrete simulation approach is used to model the gas supply system. The paper discusses how the relationships and interactions between the various parts of the system may be determined by using the simulation program which has been developed and implemented.