Correlation between Voronoi volumes in disc packings

We measure the two-point correlation of free Voronoi volumes in binary disc packings, where the packing fraction $\phi_{\rm avg}$ ranges from 0.8175 to 0.8380. We observe short-ranged correlations over the whole range of $\phi_{\rm avg}$ and anti-correlations for $\phi_{\rm avg}>0.8277$. The spatial extent of the anti-correlation increases with $\phi_{\rm avg}$ while the position of the maximum of the anti-correlation and the extent of the positive correlation shrink with $\phi_{\rm avg}$. We conjecture that the onset of anti-correlation corresponds to dilatancy onset in this system

A Note on the Complexity of Restricted Attribute-Value Grammars

The recognition problem for attribute-value grammars (AVGs) was shown to be undecidable by Johnson in 1988. Therefore, the general form of AVGs is of no practical use. In this paper we study a very restricted form of AVG, for which the recognition problem is decidable (though still NP-complete), the R-AVG. We show that the R-AVG formalism captures all of the context free languages and more, and introduce a variation on the so-called `off-line parsability constraint', the `honest parsability constraint', which lets different types of R-AVG coincide precisely with well-known time complexity classes.Comment: 18 pages, also available by (1) anonymous ftp at ftp://ftp.fwi.uva.nl/pub/theory/illc/researchReports/CT-95-02.ps.gz ; (2) WWW from http://www.fwi.uva.nl/~mtrautwe

Measurements of the τ mass and the mass difference of the τ^+ and τ^- at BABAR

We present the result from a precision measurement of the mass of the τ lepton, M_τ, based on 423  fb^(-1) of data recorded at the Υ(4S) resonance with the BABAR detector. Using a pseudomass endpoint method, we determine the mass to be 1776.68±0.12(stat)±0.41(syst)  MeV. We also measure the mass difference between the τ^+ and τ^-, and obtain (M_(τ+)-M_(τ-))/M_(AVG)^τ=(-3.4±1.3(stat)±0.3(syst))×10^(-4), where M^τ_(AVG) is the average value of M_(τ+) and M_(τ-)

Evidence of microbial activity from a shallow water whale fall (Voghera, northern Italy)

The fossil bones, associated carbonate cements and enclosing concretion of a Miocene mysticete from inner shelf deposits (Monte Vallassa Formation, northern Italy) were analyzed for evidence of microbial activity. Optical and scanning electron microscopy, Raman spectroscopy, and stable C and O isotope geochemistry were used for high spatial resolution microfacies and biosedimentological analyses. Whale cancellous bones were filled by different carbonate cements including microcrystalline dolomite, rhombohedral dolomite and sparry calcite. Biofabric and biominerals such as microbial peloids, clotted textures and pyrite framboids were associated with the dolomite cements. Dolomite inside cancellous bones and in the enclosing concretion showed similar isotopic values (avg δ 13C: -7.12‰; avg δ 18O: +3.81‰), depleted with respect to the (late) sparry calcite cement (avg δ 13C: -0.55‰; avg δ 18O: -0.98‰). Microcrystalline barite (BaSO 4) was observed on the external surface of the bones. In addition, two different types of microborings were recognized, distinguished by their size and morphology and were ascribed respectively to prokaryote and fungal trace makers. Our results testify for the development of a diverse microbial ecosystem during the decay of a shallow water whale carcass, which could be detected in the fossil record. However, none of the observed biosignatures (e.g., microbial peloids, clotted textures) can be used alone as a positive fossil evidence of the general development of a sulfophilic stage of whale fall ecological succession. The occurrence of the hard parts of chemosynthetic invertebrates associated with fossil whale bones is still the more convincing proof of the development of a sulfide-base chemoautotrophic ecosystem. © 2011 Elsevier B.V

The Magnetic Properties of Heating Events on High-Temperature Active Region Loops

Understanding the relationship between the magnetic field and coronal heating is one of the central problems of solar physics. However, studies of the magnetic properties of impulsively heated loops have been rare. We present results from a study of 34 evolving coronal loops observed in the Fe XVIII line component of AIA/SDO 94 A filter images from three active regions with different magnetic conditions. We show that the peak intensity per unit cross-section of the loops depends on their individual magnetic and geometric properties. The intensity scales proportionally to the average field strength along the loop ($B_{avg}$) and inversely with the loop length ($L$) for a combined dependence of $(B_{avg}/L)^{0.52\pm0.13}$. These loop properties are inferred from magnetic extrapolations of the photospheric HMI/SDO line-of-sight and vector magnetic field in three approximations: potential and two Non Linear Force-Free (NLFF) methods. Through hydrodynamic modeling (EBTEL model) we show that this behavior is compatible with impulsively heated loops with a volumetric heating rate that scales as $\epsilon_H\sim B_{avg}^{0.3\pm0.2}/L^{0.2\pm^{0.2}_{0.1}}$.Comment: Astrophysical Journal, in pres

Effects of AVG (aminoethoxyvinilglycine) pre-harvest drop, harvest time and fruit quality of 'Jersey Mac' apple

Çalışmada, bazı meyve çeşitlerinde hasat önü meyve dökümlerini azalttığı ve kalite özelliklerini artırdığı tespit edilen AVG nin 'Jersey Mac' elma çeşidinde, uygun uygulama zamanının ve dozunun tespit edilmesi ve bu uygulamalar ile hasat zamanının uzatılarak, meyve kalite özelliklerinin daha iyi hale getirilebilmesi amaçlanmıştır. Bu sebeple, araştırma; 2012 yılında Eğirdir Meyvecilik Araştırma İstasyonu Müdürlüğü arazisindeki 13 yaşlı M9 üzerine aşılı 'Jersey Mac' çeşidi elma ağaçlarında gerçekleştirilmiştir. AVG nin 100, 125 ve 150 ppm' lik dozları hasattan önce 3 farklı zamanda (tahmini hasattan 30 gün, 21 gün ve 7 gün önce) meyvelere uygulanmıştır. Kontrol ağaçlarına sadece su+yayıcı yapıştırıcı (Tween 20) püskürtülmüştür. AVG uygulamaları hasat zamanını 6 gün geciktirmiş ve hasat 2 defada olmak üzere 4 günlük bir periyotta tamamlanmıştır. Tüm AVG uygulamaların hasat önü meyve dökümünü azalttığı ve meyve verimini arttırdığı, hasat önü meyve dökümünü engellemede tahmini hasattan 7 gün önceki 150 ppm lik AVG uygulamasının diğer uygulamalara göre daha fazla etkili olduğu bulunmuştur. Tüm AVG uygulamaların meyve boyutunu özellikle meyve eni ve meyve ağırlığı gibi önemli kalite bileşenlerini arttırdığı saptanmış olup ekstra ve 1. Sınıf meyveler oluşturduğu tespit edilmiştir. Jersey Mac elmasında uygulamaların kontrol gruplarına göre meyve eti sertliğini arttırdığı tespit edilmiştir. AVG uygulamaları meyvelerin etilen üretimi ve solunum hızını azaltmıştır. Olgunlaşmanın gecikmesiyle meyvelerdeki renklenmenin de gecikmiş olduğu ve meyvelerdeki üst kırmızı rengin tahmini hasattan 30 gün önce uygulanmış 150 ppm lik AVG dozunda en az gerçekleştiği bulunmuştur. AVG is known to reduce preharvest fruit drop and increases fruit quality in some fruit species. In this study it was aimed to determine suitable AVG dosage and application for improving fruit quality of 'Jersey Mac' apple cultivar. For this reason, study was done with 13 years old 'Jersey Mac' variety trees grafted on M) rootstock in Eğirdir Fruit Research Station. 100, 125 and 150 ppm AVG dosages were applied in 3 different timings (before 30 days, 21 days and 7 days before harvest) to the fruits. Only water + surfactant (Tween 20) were applied to control treatment trees. AVG treatments delayed the harvest for 6 days and harvest was completed in for 4 days time by harvesting twice. All AVG applications reduced the pre-harvest fruit drop and increased the yield and 150 ppm AVG dosage was determined most effective dosage was determined most effective dosage for preharvest fruit drop. All AVG applications increased fruit sizes especially fruit diameter and fruit weight all quality characterics were increased by AVG ekstra and first class fruits were determined. All AVG applications increased the fruit firmness according to control treatment. AVG treatments decreased fruits ethylene production and respiration rates. Coloration of fruits were delayed because of AVG applications and red colour of the apples were occurred minimum at 150 ppm AVG dosage which was applied 30 days before the harvest

Adaptive Regularized Submodular Maximization

In this paper, we study the problem of maximizing the difference between an adaptive submodular (revenue) function and a non-negative modular (cost) function. The input of our problem is a set of n items, where each item has a particular state drawn from some known prior distribution The revenue function g is defined over items and states, and the cost function c is defined over items, i.e., each item has a fixed cost. The state of each item is unknown initially and one must select an item in order to observe its realized state. A policy ? specifies which item to pick next based on the observations made so far. Denote by g_{avg}(?) the expected revenue of ? and let c_{avg}(?) denote the expected cost of ?. Our objective is to identify the best policy ?^o ? arg max_? g_{avg}(?)-c_{avg}(?) under a k-cardinality constraint. Since our objective function can take on both negative and positive values, the existing results of submodular maximization may not be applicable. To overcome this challenge, we develop a series of effective solutions with performance guarantees. Let ?^o denote the optimal policy. For the case when g is adaptive monotone and adaptive submodular, we develop an effective policy ?^l such that g_{avg}(?^l) - c_{avg}(?^l) ? (1-1/e-?)g_{avg}(?^o) - c_{avg}(?^o), using only O(n?^{-2}log ?^{-1}) value oracle queries. For the case when g is adaptive submodular, we present a randomized policy ?^r such that g_{avg}(?^r) - c_{avg}(?^r) ? 1/eg_{avg}(?^o) - c_{avg}(?^o)

Efeito do tratamento com aminoetoxivinilglicina (AVG) na queda pré-colheita e na maturação dos frutos em macieiras

ABSTRACTApple trees cultivars Gala and Fuji were sprayed four weeks before commercial harvest with aminoethoxyvinilglycine (AVG), at doses of 0, 125, or 250 mg L-1, and assessed for preharvest fruit drop, fruit growth, and maturation on tree. In 'Gala', 64 days after AVG spraying, fruit drop for control treatment was 85%, and AVG (at 125 and 250 mg L-1) reduced it to 10%. In 'Fuji', 64 days after AVG spraying, fruit drop for control was 6%, while treatments with AVG (at 125 and 250 mg L-1) increased fruit drop to 10%. AVG was a powerful retardant of fruit maturation for 'Gala' but not for 'Fuji'. In 'Gala', the most affected attribute was the skin background color, followed, in decreasing order, by soluble solids content, the starch index, skin red color, the flesh firmness, and titratable acidity. In 'Gala', only flesh firmness retention was improved by increasing AVG dose from 125 mg L-1 to 250 mg L-1. The AVG at 250 mg L-1 inhibited "Gala" late fruit growth but not 'Fuji'. __________________________________________________________________________________ RESUMOMacieiras, das cultivares Gala e Fuji, foram pulverizadas quatro semanas antes do início da colheita comercial dos frutos com aminoetoxivinilglicina (AVG), nas concentrações de 0; 125 ou 250 mg L-1, e avaliadas quanto à queda de frutos na pré-colheita, o crescimento e maturação dos frutos. Na cultivar Gala, 64 dias após a pulverização com AVG, a queda pré-colheita no tratamento-controle era de 85%, mas os tratamentos com AVG (125 e 250 mg L-1) reduziram esta queda para 10%. Na cultivar Fuji, 64 dias após a pulverização com AVG, a queda de frutos no tratamento-controle era de 6%, e os tratamentos com AVG (125 e 250 mg L-1) aumentaram esta queda para 10%. Tratamentos com AVG retardaram substancialmente a maturação dos frutos da cultivar Gala, mas não da 'Fuji'. Na cultivar Gala, o atributo mais afetado foi a cor de fundo da casca, seguido, em ordem decrescente, pelo conteúdo de sólidos solúveis totais, índice de iodo-amido, cor vermelha da casca, firmeza de polpa e acidez titulável. Na cultivar Gala, apenas a retenção de firmeza de polpa foi significativamente aumentada com o aumento na concentração de AVG de 125 mg L-1 para 250 mg L-1. A concentração de 250 mg L-1 inibiu o crescimento final de frutos na cultivar Gala, mas não na 'Fuji'