Towards an improved understanding of eta --> gamma^* gamma^*

We argue that high-quality data on the reaction $e^+e^-\to \pi^+\pi^-\eta$ will allow one to determine the double off-shell form factor $\eta \to \gamma^*\gamma^*$ in a model-independent way with controlled accuracy. This is an important step towards a reliable evaluation of the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon. When analyzing the existing data for $e^+e^- \to \pi^+\pi^-\eta$ in the range of total energies $1\text{GeV}^2<Q_2^2<(4.5\text{GeV})^2$, we demonstrate that the double off-shell form factor $F_{\eta\gamma^*\gamma^*}(Q_1^2,Q_2^2)$ is consistent with the commonly employed factorization ansatz at least for $Q_1^2<1\text{GeV}^2$, if the effect of the $a_2$ meson is taken into account. However, better data are needed to draw firm conclusions.Comment: 7 pages, 3 figure

Kecernaan Bahan Kering Dan Bahan Organik Ransum Ternak Kambing Kacang Yang Diberi Suplementasi Dedak Padi Dan Daun Turi

Dry And Organic Matter Digestibility Of Kacang Goats Offered Native Grass Supplemented With Rice Meal And Sesbania Leafs. A study on the effect of rice meal and sesbania leafs supplementation on dry and organic matter digestibility of kacang goats offered native grass has been carried out using 12 male goats (6-9 months old) in a block completely randomized design. The goats were grouped into 4 and then each group was treated as R0 = 100% native grass (control), R1 = 75% native grass + 20% sesbania leafs + 5% rice meal, R2 = 50% native grass + 40% sesbania leafs + 10% rice meal or R3 = 25% native grass + 60% sesbania leafs + 15% rice meal. Replication was 3 times for each treatment so there are 12 experimental units. Data was analyzed by Analysis of variance (ANOVA) and the difference among treatments was further analyzed by Duncan\u27s multiple range tests. Results showed that there is a strong significant difference (P&lt;0.01) among dry matter digestibility. Further test showed that there is a strong significant difference (P&lt;0.01) between R3 and either R0, R1 or R2. Between R2 and R0 there is only a significant (P&lt;0.05) difference. There is no difference (P&gt;0.05) between R2 and R1 as well as R1 and R0. Organic matter digestibility was significantly (P&lt;0.01) differ among treatments. Further test showed that a strong significant (P&lt;0.01) difference was recorded between R3 and either R0, R1 or R2. Similarly, the difference between R2 and R0 as well as R1 and R0 was recorded. There is no significant difference (P&gt;0.05) between R2 and R1. It can be concluded that dry and organic matter digestibility of kacang goats increases according to the increase of sesbania leafs and rice meal supplementation. It was suggested to use sesbania leafs and rice meal in the ration of fattening goats and also it was suggested a further experiment by using different ration formulation composed of these feedstuffs

Neuroradiological findings in Alagille syndrome

Alagille syndrome (ALGS) is a multisystemic disease caused by mutations in genes of Notch pathway, which regulates embryonic cell differentiation and angiogenesis. Clinically, ALGS is characterized by cholestasis, cardiac defects, characteristic facial features, skeletal and ophthalmologic abnormalities. The aim of this review is to illustrate neuroradiological findings in ALGS, which are less well-known and prevalent, including cerebrovascular anomalies (such as aneurysms, dolichoectasia, Moyamoya syndrome and venous peculiarities), Chiari 1 malformation, craniosynostosis, intracranial hypertension, and vertebral anomalies (namely butterfly vertebra, hemivertebra, and craniocervical junction anomalies). Rarer cerebral midline malformations and temporal bone anomalies have also been described

Sustainability of Renewable Energy Systems with Special Reference to Ocean Thermal Energy Conversion Schemes

It was required to determine relative merits of commonly used renewable energy (RE) systems for which estimation of their individual sustainability percent achievable was chosen as the single criterion assessment tool. The methodology developed for estimating sustainability included identification of individual sustainability indices (SI) and examining the scope of sustainability percent input /kWh power generation for each of SI indices and summing them up estimating total sustainability accrued from respective RE systems. The RE systems studied included photo-voltaic (PV) cells, bio-fuels, on-shore & off-shore wind energy and OTEC schemes. Coal power plant being commercially viable was studied as the referral energy scheme. Nine SI indices identified for study included resource potential, greenhouse gas saving, influence on flora & fauna, effects on human health, land loss aspects, food and potable water security, economy evaluation, and improvement in quality of life from economic growth. Total sustainability achievable showed the highest in OTEC, followed by wind, bio-fuels and PV, respectively. SI index on quality of life showed RE schemes like OTEC & bio-fuels competing equally with coal power plant having poor sustainability with the least power generation cost; whence Hybrid OTEC showed the highest sustainability with high power production cost. Four fold approaches have been suggested for reducing power generation cost of OTEC. (i) Adopting economically viable scheme of not less than 40 MW. (ii) Heating up the working fluid with solar irradiation, terming SOTEC scheme. (iii) Saving cable laying cost, from hydrogen production utilizing the power generated. (iv) Hybridization of OTEC scheme

The quassinoid derivative NBT-272 targets both the AKT and ERK signaling pathways in embryonal tumors

The quassinoid analogue NBT-272 has been reported to inhibit MYC, thus warranting a further effort to better understand its preclinical properties in models of embryonal tumors (ET), a family of childhood malignancies sharing relevant biological and genetic features such as deregulated expression of MYC oncogenes. In our study, NBT-272 displayed a strong anti-proliferative activity in vitro that resulted from the combination of diverse biological effects, ranging from G1/S arrest of the cell cycle to apoptosis and autophagy. The compound prevented the full activation of both the eukaryotic initiation factor 4E (eIF4E) and its binding protein 4EBP-1, regulating cap-dependent protein translation. Interestingly, all responses induced by NBT-272 in ET could be attributed to interference with two main pro-proliferative signaling pathways, i.e. the AKT and the MEK/extracellular signal-regulated kinase (ERK) pathways. These findings also suggested that the depleting effect of NBT-272 on MYC protein expression occurred via indirect mechanisms, rather than selective inhibition. Finally, the ability of NBT-272 to arrest tumor growth in a xenograft model of neuroblastoma plays a role in the strong anti-tumor activity of this compound, both in vitro and in vivo, with its potential to target cell-survival pathways that are relevant for the development and progression of ET

Towards Graphene Nanoribbon-based Electronics

The successful fabrication of single layer graphene has greatly stimulated the progress of the research on graphene. In this article, focusing on the basic electronic and transport properties of graphene nanoribbons (GNRs), we review the recent progress of experimental fabrication of GNRs, and the theoretical and experimental investigations of physical properties and device applications of GNRs. We also briefly discuss the research efforts on the spin polarization of GNRs in relation to the edge states.Comment: 9pages,10figure

Sabotage in Contests: A Survey

A contest is a situation in which individuals expend irretrievable resources to win valuable prize(s). ‘Sabotage’ is a deliberate and costly act of damaging a rival’s' likelihood of winning the contest. Sabotage can be observed in, e.g., sports, war, promotion tournaments, political or marketing campaigns. In this article, we provide a model and various perspectives on such sabotage activities and review the economics literature analyzing the act of sabotage in contests. We discuss the theories and evidence highlighting the means of sabotage, why sabotage occurs, and the effects of sabotage on individual players and on overall welfare, along with possible mechanisms to reduce sabotage. We note that most sabotage activities are aimed at the ablest player, the possibility of sabotage reduces productive effort exerted by the players, and sabotage may lessen the effectiveness of public policies, such as affirmative action, or information revelation in contests. We discuss various policies that a designer may employ to counteract sabotage activities. We conclude by pointing out some areas of future research