New results related to a conjecture of Manickam and Singhi

In 1998 Manickam and Singhi conjectured that for every positive integer $d$ and every $n \ge 4d$, every set of $n$ real numbers whose sum is nonnegative contains at least $\binom {n-1}{d-1}$ subsets of size $d$ whose sums are nonnegative. In this paper we establish new results related to this conjecture. We also prove that the conjecture of Manickam and Singhi does not hold for $n=2d+2$

Correlation among QPO frequencies and Quiescence-state Duration in Black Hole Candidate GRS 1915+105

We discover a definite correlation between the frequency of the quasi-periodic oscillations (QPO) in quiescence states and the duration of the quiescence state of the transient X-ray source GRS 1915+105. We find that while the QPO frequency can be explained with the oscillation of shocks in accretion flows, the switching of burst to quiescence states (and vice versa) and their duration can be explained by assuming an outflow from the post-shock region. The duration of the quiescence state is inversely related to the QPO-frequency. We derive this relation. We also find the correlation between the observed low ($\sim 0.001-0.01$Hz) and the intermediate (1-10Hz) QPO frequencies. Our analytical solutions are verified by analyzing several days of public-domain data from RXTE.Comment: Latex, 13 pages with 3 figures; Accepted for Publication in Astrophysical Journal Letter

Non-vanishing of LL-functions associated to cusp forms of half-integral weight

In this article, we prove non-vanishing results for $L$-functions associated to holomorphic cusp forms of half-integral weight on average (over an orthogonal basis of Hecke eigenforms). This extends a result of W. Kohnen to forms of half-integral weight.Comment: 8 pages, Accepted for publication in Oman conference proceedings (Springer

Application of a Combined Active Control and Fault Detection Scheme to an Active Composite Flexible Structure.

In this paper, the problem of increasing reliability of active control procedure is considered. Indeed, a design method of rejection perturbation in presence of potentially faults, on a flexible structure with integrated piezo-ceramics, is presented. The piezo-ceramics are used as actuators and sensors. A single unit based solution, which handles both control action and fault diagnosis is proposed. The algorithm uses H∞ optimization techniques. A full order model of the structure is first obtained via both finite-element (FE) approach and identification procedure. This model is then reduced in order to be used in our robust approach. By a suitable choice of weightings functions, the provided method is able to reject disturbance robustly and to estimate occurred faults. The case of sensors and actuators faults is discussed. The choice of weightings for diagnosis and control systems is also tackled. Finally, the effectiveness of this integrated method is confirmed by both simulation and experimental results

The Cloning, Characterisation and Antisense Cassettes Construction for Some Pigmentation Genes from Oncidium SPP.

Genes that are responsible for color formation within the anthocyanin and carotenoid biosynthesis pathway have been isolated, studied and manipulated to produce novel colors in many plant species. Therefore, in this study, the genes that are involved in flower color formation namely CHS, F3H, DFR and PSY will be isolated and studied in the orchid species, Oncidium goldiana. The construction of antisense cassettes will also be carried out for CHS, DFR and PSY. RNA was isolated from various stages of Oncidium go/diana and its purity and concentration was determined. Partial genes of CHS (605bp), F3H (503bp), DFR (415bp) and PSY (543bp) was isolated from flower petals by RT-PCR using degenerate primers. A BLAST search for homology revealed that these sequences had high homology at both the amino and nucleic acid levels with other known plantThe temporal and spatial gene expression studies using semi-quantitative RT -PCR showed that F3H and DFR were floral specific and they had the highest expression at the yellow buds stage. The level of CHS was the highest in partially opened flowers and PSY was expressed at its highest levels in green buds. CHS and PSY were not floral specific as they were also present in leaves. The antisense cassettes were constructed for CHS, DFR and PSY. These vectors were driven by a 35S promoter and Nos 3' terminator sequence. The CHS vector was 13'480bp, the DFR was 13380bp and PSY was 13430bp. These antisense cassettes were suitable for transformation by biolistic gun bombardment or via Agrobacleriunt infectio

The Nutritional And Antinutritional Composition Of Strobilanthes Crispus (L.)Bremek And Its Anticancer Effect During Hepatocarcinogenesis

The nutritional and antinutritional composition of Strobilanthes crispus (L. ) Bremek or Saricocalyx crispus (L.) Bremek (Acanthacea) , and its anticancer effect during hepatocarcinogenesis were studied to investigate the possible cancer suppressive effect of the component existed in the leaves. The nutritional composition studied were of the proximate composition and antioxidant activity of ferric thiocyanate and thiobarbituric acid methods. The antinutritional factors studied were catechin, tannin, caffeine and alkaloid. All data were compared to Yerbamate, green tea, black tea and Indian tea. The leaves contained high amount of water soluble vitamins and total ash leading to high amount of minerals such as potassium, calcium, sodium, iron and phosphorus. The leaves contained low level of antinutritional factors contributing to better absorption of iron and water soluble vitamins. Its catechins showed highest antioxidant activity when compared to Yerbamate and Vitamin E