814 research outputs found
CH2D+, the Search for the Holy Grail
CH2D+, the singly deuterated counterpart of CH3+, offers an alternative way
to mediate formation of deuterated species at temperatures of several tens of
K, as compared to the release of deuterated species from grains. We report a
longstanding observational search for this molecular ion, whose rotational
spectroscopy is not yet completely secure. We summarize the main spectroscopic
properties of this molecule and discuss the chemical network leading to the
formation of CH2D+, with explicit account of the ortho/para forms of H2, H3+
and CH3+. Astrochemical models support the presence of this molecular ion in
moderately warm environments at a marginal level.Comment: 25 pages, 6 Figures Accepted in Journal of Physical Chemistry A. "Oka
Festschrift: Celebrating 45 years of Astrochemistry
Nitrogen isotopic ratios in Barnard 1: a consistent study of the N2H+, NH3, CN, HCN and HNC isotopologues
The 15N isotopologue abundance ratio measured today in different bodies of
the solar system is thought to be connected to 15N-fractionation effects that
would have occured in the protosolar nebula. The present study aims at putting
constraints on the degree of 15N-fractionation that occurs during the
prestellar phase, through observations of D, 13C and 15N-substituted
isotopologues towards B1b. Both molecules from the nitrogen hydride family,
i.e. N2H+ and NH3, and from the nitrile family, i.e. HCN, HNC and CN, are
considered in the analysis. As a first step, we model the continuum emission in
order to derive the physical structure of the cloud, i.e. gas temperature and
H2 density. These parameters are subsequently used as an input in a non-local
radiative transfer model to infer the radial abundances profiles of the various
molecules. Our modeling shows that all the molecules are affected by depletion
onto dust grains, in the region that encompasses the B1-bS and B1-bN cores.
While high levels of deuterium fractionation are derived, we conclude that no
fractionation occurs in the case of the nitrogen chemistry. Independently of
the chemical family, the molecular abundances are consistent with 14N/15N~300,
a value representative of the elemental atomic abundances of the parental gas.
The inefficiency of the 15N-fractionation effects in the B1b region can be
linked to the relatively high gas temperature ~17K which is representative of
the innermost part of the cloud. Since this region shows signs of depletion
onto dust grains, we can not exclude the possibility that the molecules were
previously enriched in 15N, earlier in the B1b history, and that such an
enrichment could have been incorporated into the ice mantles. It is thus
necessary to repeat this kind of study in colder sources to test such a
possibility.Comment: accepted in A&
Merging fragments of classical logic
We investigate the possibility of extending the non-functionally complete
logic of a collection of Boolean connectives by the addition of further Boolean
connectives that make the resulting set of connectives functionally complete.
More precisely, we will be interested in checking whether an axiomatization for
Classical Propositional Logic may be produced by merging Hilbert-style calculi
for two disjoint incomplete fragments of it. We will prove that the answer to
that problem is a negative one, unless one of the components includes only
top-like connectives.Comment: submitted to FroCoS 201
Efektifitas Kirinyuh (Chromolaena Odorata L.) terhadap Keragaman Hama dan Musuh Alami pada Tumpangsari Tanaman Jagung dan Kedelai
Sistem tumpangsari telah banyak diketahui bahwa produksi tanaman secara keseluruhan memberikan hasil yang lebih tinggi apabila kombinasi tanaman yang diusahakan dilakukan dengan tepat. Tanaman Chromolaena odorata L. mempunyai senyawa metabolit sekunder, flavononas, flavonas, khalkones, tannin asam aromatik dan minyak esensial. Tujuan penelitian untuk mengetahui pengaruh kirinyuh sebagai tanaman sela terhadap perkembangan hama dan musuh alami kedelai dan jagung pada sistem tumpangsari. Percobaan yang digunakan Rancangan Acak Kelompok (RAK) satu faktor yaitu C0 (Kedelai X Jagung (kontrol); C1 (3 tanaman C. odorata X Kedelai X Jagung); C2 (6 tanaman C. odorata X Kedelai X Jagung); C3 (9 tanaman C. odorata X Kedelai X Jagung) dan C4 (12 tanaman C. odorata X Kedelai X Jagung), Semua perlakuan diulang tiga kali sehingga didapat 15 kombinasi perlakuan. Data dianalisa dengan sidik ragam (ANOVA). Hasil penelitian, Indeks keragaman tertinggi yaitu 2.50 terdapat di C0, dan indeks keragaman terendah yaitu 2.28 terdapat pada C1, penanaman tanaman kirinyuh di sela-sela tanaman jagung dan kedelai membuat agroekosistem sangat cocok bagi musuh alami untuk bernaung sehingga keberadaan musuh alami lebih meningkat bila dibandingkan dengan hama, C1 tingkat kerusakan tanaman jagung yang minimum yaitu 3.03 %, C1 menghasilkan jumlah polong kedelai maksimum 79.77 buah dan berat biji maksimum 20.21 g, C1 menghasilkan berat tongkol maksimum 753.3 g dan berat biji maksimum 586.7 g
Analisis Kinerja Keuangan Berbasis Economic Value Added (Eva) Pada PT. Bank Sulutgo
The purpose of this study is to find out how much Economic Value Addedgenerated by PT. Bank SULUTGO in 2014-2016. It is known that PT. Bank SULUTGOis a regional bank of North Sulawesi and Gorontalo which owns shares from variousregions and several companies. It is known that the capital annually PT. BankSULUTGO in 2014-2016 always increases. But with the increase in capital whether ithas made the company able to improve the performance of the company or increase therevenue of the company so as to be able to distribute the fair share of the results to theshareholders of the company. The purpose of this study is "Financial PerformanceAnalysis Based on Economic Value Added at PT. Bank SULUTGO". Financialperformance is needed by the company to evaluate the performance or as a foundationof the company to improve the company\u27s performance. Financial performanceaccording to Ikatan Akuntansi Indonesia (2007) is the determination of the company\u27sability to manage and control its own resources. While EVA is an effectivecommunication tool for value creation that can be reached by line managers thatultimately drive company performance and to connect with capital markets (Young andO\u27Bryne, 2001). The research method used is quantitative descriptive method by usinganalysis tools in the form of Economic Value added to calculate NOPAT, InvestedCapital, WACC, Capital Charges and EVA. Based on the results of research EVAanalysis at PT. Bank SULUTGO 2014-2016 year turned out to fluctuate because EVAcompanies every year down and up. Nevertheless PT. Bank SULUTGO turned out tohave created a positive value in the company in 2014-2016. In 2014 the company is ableto create EVA of Rp. 97,596 (in millions of rupiah), but in 2015 the company\u27s EVAdecreased by 26.08% to Rp. 72,140 (in millions of rupiah) and in 2016 again increasedby 34.01% to Rp. 96,680 (in millions of rupiah). Thus the management has been able tocreate a positive value on the company well and shareholders can entrust theirinvestment to the company
Cardiac Tamponade Secondary to Methicillin-Resistant Staphylococcus Aureus Pericarditis
As pericardites bacterianas, apesar da sua
baixa incidência e das terapêuticas actuais,
apresentam um prognóstico desfavorável,
sobretudo quando causadas por Staphylococcus
aureus meticilino resistente (MRSA). O
Tamponamento cardíaco é uma complicação
potencialmente letal nos doentes com
pericardites por este agente. Numa Unidade de
Cuidados Intensivos, para além da
imunossupressão, constituem factores
predisponentes para este tipo de infecção, a
elevada taxa de colonização nasal e cutânea,
assim como a utilização de técnicas invasivas (1)
entre as quais a simples colocação de catéteres
intravenosos.
Relatam-se dois casos clínicos de
tamponamento cardíaco em doentes jovens, no
contexto de imunossupressão de diferentes
etiologias (infecção HIV e pós transplante
hepático). Os internamentos foram complicados
de quadros sépticos importantes com
isolamento de MRSA nos líquidos biológicos e
desenvolvimento de pericardite bacteriana e
subsequente tamponamento cardíaco.
Os autores salientam a importância dos
quadros clínicos infecciosos em doentes
imunodeprimidos, que constituem uma
população cada vez mais numerosa, e a
importância da monitorização ecocardiográfica
na evolução prognóstica das pericardites
bacterianas no contexto de sépsis
Quantum Bose and Fermi gases with large negative scattering length in the 2-body S-matrix approximation
We study both Bose and Fermi gases at finite temperature and density in an
approximation that sums an infinite number of many body processes that are
reducible to 2-body scatterings. This is done for arbitrary negative scattering
length, which interpolates between the ideal and unitary gas limits. In the
unitary limit, we compute the first four virial coefficients within our
approximation. The second virial coefficient is exact, and we extend the
previously known result for fermions to bosons, and also for both bosons and
fermions for the upper branch on the other side of unitarity (infinitely large
positive scattering length). Assuming bosons can exist in a meta-stable state
before undergoing mechanical collapse, we map out the critical temperatures for
strongly coupled Bose-Einstein condensation as a function of scattering length.Comment: 22 pages, 8 figures. Version 2: 1 additional reference (only change
Bleaching Response of Coral Species in the Context of Assemblage Response
Caribbean coral reefs are declining due to a mosaic of local and global stresses, including climate change-induced thermal stress. Species and assemblage responses differ due to factors that are not easily identifiable or quantifiable. We calculated a novel species-specific metric of coral bleaching response, taxon-α and -β, which relates the response of a species to that of its assemblages for 16 species over 18 assemblages. By contextualizing species responses within the response of their assemblages, the effects of environmental factors are removed and intrinsic differences among taxa are revealed. Most corals experience either a saturation response, overly sensitive to weak stress (α \u3e 0) but under-responsive compared to assemblage bleaching (β \u3c 1), or a threshold response, insensitive to weak stress (α \u3c 0) but over-responsive compared to assemblage bleaching (β \u3e 1). This metric may help reveal key factors of bleaching susceptibility and identify species as targets for conservation
Some inequalities for the Tutte polynomial
We prove that the Tutte polynomial of a coloopless paving matroid is convex
along the portions of the line segments x+y=p lying in the positive quadrant.
Every coloopless paving matroids is in the class of matroids which contain two
disjoint bases or whose ground set is the union of two bases of M*. For this
latter class we give a proof that T_M(a,a) <= max {T_M(2a,0), T_M(0,2a)} for a
>= 2. We conjecture that T_M(1,1) <= max {T_M(2,0), T_M(0,2)} for the same
class of matroids. We also prove this conjecture for some families of graphs
and matroids.Comment: 17 page
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