2,291 research outputs found

    Visual orbit for the low-mass binary Gliese 22 AC from speckle interferometry

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    Based on 14 data points obtained with near-infrared speckle interferometry and covering an almost entire revolution, we present a first visual orbit for the low-mass binary system Gliese 22 AC. The quality of the orbit is largely improved with respect to previous astrometric solutions. The dynamical system mass is 0.592 +- 0.065 solar masses, where the largest part of the error is due to the Hipparcos parallax. A comparison of this dynamical mass with mass-luminosity relations on the lower main sequence and theoretical evolutionary models for low-mass objects shows that both probably underestimate the masses of M dwarfs. A mass estimate for the companion Gliese 22 C indicates that this object is a very low-mass star with a mass close to the hydrogen burning mass limit.Comment: Accepted by Astronomy and Astrophysics, 6 pages, 2 figure

    Behavior’s Green Consumer Model Development (Green Consumer Study in North Sulawesi, Indonesia)

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    The purpose of this study is to analyze and explain the relationships and effects of green marketing, theory of planned behavior on green consumerism and environmental sustainability through green consumer behavior. The research design uses a quantitative approach through survey methods. The population in this study are consumers who buy and are willing to conduct interviews about green products in modern markets and souvenirs in a number of districts / cities in North Sulawesi province. The research sample analyzed was 381 respondents. Sampling using a purposive sampling technique with data analysis techniques using structural equation models with the help of AMOS, SPSS, and Ms Exel programs. A number of variables in this study are green marketing, theory of planned behavior, green consumer behavior, green consumerism and environmental sustainability.The research findings produce: 1) Equation 1 formed Y1 = 0.408 X1 + 0.195 X2, meaning that green marketing and the theory of planned behavior have a positive relationship and have a significant effect on green consumer behavior; 2) Persuasion 2 is formed Y2 = 0.137 X1 + 0.130 X2 + 0.489 Y1, meaning green marketing and theory of planned behavior have a positive relationship and have a significant effect on green consumerism through green consumer behavior; 3) Perservation 3 is formed Y3 = 0.122 X1 + 0.021 X2 + 0.570 Y1, meaning that green marketing and theory of planned behavior have a positive relationship and have a significant effect on environmental sustainability through green consumer behavior. With the findings of this study, it can be concluded that the green consumer behavior model is a model that can be considered in developing green product development strategies. Keywords: Green Marketing, Theory of Planned Behaviour, Green consumer behavior, Green consumerism, Environmental sustainability DOI: 10.7176/EJBM/11-27-15 Publication date:September 30th 201

    Audit of failure rate of sulfadoxine/pyrimethamine combined with chloroquine to treat falciparum malaria at single fourteen-day follow-up

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    Objective. To assess the failure rate of the present first line treatment regime for uncomplicated falciparum malaria of sulfadoxine/pyrimethamine combined with chloroquine. Design. A before-after study1 Setting. Ndumo Clinic, Ingwavuma District, South Africa, October 2000 Study Group. 55 patients presenting to Ndumo clinic with uncomplicated malaria and malaria trophozoites visible on thin film. Main outcome measures:Trophozoite count on thick film at day 14. Results. 15 out of 37 patients who returned for follow-up still had trophozoites on thick film. Symptoms of most patients at day 0 and day 14 were mild, parasite counts before and after treatment were low, and trophozoites were atypical. Conclusions. There appears to be an unacceptably high day 14 failure rate with the combination of sulfadoxine/pyrimethamine and chloroquine.The mildness of symptoms, low parasite counts and atypical trophozoites suggest immunity to falciparum malaria amongst the local population. With few antimalarials to chose from, the difficult question as to future treatment of uncomplicated malaria arises. Keywords: Falciparum malaria, chloroquine, sulfadoxine, pyrimethamine SA Fam Prac Vol.25(3) 2002: 4-

    Orbits and Masses in the multiple system LHS 1070

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    We present a study of the orbits of the triple system LHS1070, with the aim to determine individual masses of its components. Sixteen new relative astrometric positions of the three components in the K band were obtained with NACO at the VLT, Omega CASS at the 3.5m telescope on Calar Alto, and other high-spatial-resolution instruments. We combine them with data from the literature and fit orbit models to the dataset. We derive an improved fit for the orbit of LHS1070B and C around each other, and an estimate for the orbit of B and C around A. The orbits are nearly coplanar, with a misalignment angle of less than 10{\deg}. The masses of the three components are M_A = 0.13 - 0.16 Msun, M_B = 0.077+/-0.005 Msun, and M_C = 0.071+/-0.004 Msun. Therefore, LHS1070C is certainly, and LHS1070B probably a brown dwarf. Comparison with theoretical isochrones shows that LHS1070A is either fainter or more massive than expected. One possible explanation would be that it is a binary. However, the close companion reported previously could not be confirmed.Comment: 9 pages, 8 figures, accepted by Astronomy and Astrophysic

    M dwarf stars in the light of (future) exoplanet searches

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    We present a brief overview of a splinter session on M dwarf stars as planet hosts that was organized as part of the Cool Stars 17 conference. The session was devoted to reviewing our current knowledge of M dwarf stars and exoplanets in order to prepare for current and future exoplanet searches focusing in low mass stars. We review the observational and theoretical challenges to characterize M dwarf stars and the importance of accurate fundamental parameters for the proper characterization of their exoplanets and our understanding on planet formation.Comment: 4 pages, 1 figure. Summary of the splinter session "M dwarf stars in the light of (future) exoplanet searches" held at the 17th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, June 28th 2012, Barcelona, Spain. Submitted for publication in Astronomische Nachrichten - Astronomical Notes (AN) 334, Issue 1-2, Eds Klaus Strassmeier and Mercedes L\'opez-Morale

    Consumption Behavior of Economics Education Students Faculty of Economics, State University of Manado

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    This study aims to determine the influence of financial literacy and social environmental factors on consumption behaviour of Economics Faculty of Economics students of Manado State University. The design of this study using the quantitative approach with survey method, with the number of samples is 67 students as respondents through proportionate stratified random sampling. The research instrument used questionnaire with a Likert scale which then tested the validity and reliability. Data analysis techniques include 1) Descriptive analysis; 2) Classical assumption test, and 3) Multiple linear regression analysis. The results showed: 1). There is a significant influence on financial literacy and student consumption behaviour, with the influence of financial literacy on student consumption behaviour of 54.4%; 2). There is a significant influence on social environment factor with student consumption behaviour, with the influence of social environment factor to student consumption behaviour equal to 37.5%; and 3). There is the influence of variable of financial literacy and social environment factor to student consumption behaviour variable with a contribution equal to 78.6%. Conclusion, partially or simultaneously financial literacy and social environmental factors have a significant effect on the consumption behaviour of students of Economics Education Faculty of Economics, State University of Manado

    Pengaruh warna lampu light emitting diode dalam air terhadap hasil tangkapan ikan Teri (Stolephorus commersonii) dengan bagan

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    Lift nets is one of the fishing gear which operate at the night.  This fishing gear are using light as a aids to attract fish into the fishing area.  Research on the use of LED lights in water on lift nets is carried out in Tateli Weru Waters, with the aim to see how the effect of using different color underwater LED lights on anchovy catches (Stolephorus commersonii), and knowing the amount of anchovy (Stolephorus commersonii) catch on lift net using the experimental method, where data is analyzed using Completely Randomized Block Design (RCBD), and continued by Least Significant Difference test (LSD).  Trial of anchovy fishing (Stolephorus commersonii) was conducted in December 2018 for 10 days by operating boat lift nets using green, blue and green-blue LED lights.  The results showed that the use of LED light colors in blue water had a very significant effect on the amount of anchovy catch (Stolephorus comersonii) compared to to the color of LED lights in green-blue and green water.  Whereas the use of LED light colors in blue-green water with green is not statistically significantly different from the amount of anchovy caught (Stolephorus comersonii).ABSTRAKBagan merupakan salah satu alat penangkapan ikan yang dioperasikan pada malam hari.  Alat tangkap ini menggunakan cahaya lampu sebagai alat bantu untuk menarik ikan masuk ke dalam area penangkapan.  Penelitian mengenai penggunaan lampu LED dalam air pada bagan dilakukan di Perairan Tateli Weru, dengan tujuan untuk melihat bagaimana pengaruh penggunaan lampu LED bawah air dengan warna yang berbeda terhadap hasil tangkapan ikan teri (Stolephorus commersonii), serta mengetahui jumlah hasil tangkapan ikan teri (Stolephorus commersonii) pada bagan dengan menggunakan metode eksperimental, dimana data dianalisis dengan menggunakan  Rancangan Acak Kelompok (RAK) dan dilanjutkan dengan uji Beda Nyata Terkecil (BNT).  Uji coba penangkapan ikan teri (Stolephorus commersonii) dilakukan pada bulan Desember 2018 selama 10 hari dengan mengoperasikan bagan apung menggunakan lampu LED hijau, biru dan hijau-biru.  Hasil penelitian menunjukkan bahwa penggunaan warna lampu LED dalam air biru memberikan pengaruh yang sangat nyata terhadap jumlah hasil tangkapan ikan teri (Stolephorus comersonii) dibandingkan warna lampu LED dalam air hijau-biru dan hijau.  Sedangkan antara penggunaan warna lampu LED dalam air hijau-biru dengan hijau secara statistik tidak berbeda nyata terhadap jumlah hasil tangkapan ikan teri (Stolephorus comersonii)

    The neonicotinoid insecticide Imidacloprid repels pollinating flies and beetles at field-realistic concentrations

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    Neonicotinoids are widely used systemic insecticides which, when applied to flowering crops, are translocated to the nectar and pollen where they may impact upon pollinators. Given global concerns over pollinator declines, this potential impact has recently received much attention. Field exposure of pollinators to neonicotinoids depends on the concentrations present in flowering crops and the degree to which pollinators choose to feed upon them. Here we describe a simple experiment using paired yellow pan traps with or without insecticide to assess whether the commonly used neonicotinoid imidacloprid repels or attracts flying insects. Both Diptera and Coleoptera exhibited marked avoidance of traps containing imidacloprid at a field-realistic dose of 1 μg L-1, with Diptera avoiding concentrations as low as 0.01 μg L-1. This is to our knowledge the first evidence for any biological activity at such low concentrations, which are below the limits of laboratory detection using most commonly available techniques. Catch of spiders in pan traps was also slightly reduced by the highest concentrations of imidacloprid used (1 μg L-1), but catch was increased by lower concentrations. It remains to be seen if the repellent effect on insects occurs when neonicotinoids are present in real flowers, but if so then this could have implications for exposure of pollinators to neonicotinoids and for crop pollination. © 2013 Easton, Goulson

    Bell Correlations and the Common Future

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    Reichenbach's principle states that in a causal structure, correlations of classical information can stem from a common cause in the common past or a direct influence from one of the events in correlation to the other. The difficulty of explaining Bell correlations through a mechanism in that spirit can be read as questioning either the principle or even its basis: causality. In the former case, the principle can be replaced by its quantum version, accepting as a common cause an entangled state, leaving the phenomenon as mysterious as ever on the classical level (on which, after all, it occurs). If, more radically, the causal structure is questioned in principle, closed space-time curves may become possible that, as is argued in the present note, can give rise to non-local correlations if to-be-correlated pieces of classical information meet in the common future --- which they need to if the correlation is to be detected in the first place. The result is a view resembling Brassard and Raymond-Robichaud's parallel-lives variant of Hermann's and Everett's relative-state formalism, avoiding "multiple realities."Comment: 8 pages, 5 figure

    Design and development of a speech synthesis software for colombian spanish applied to communication through mobile devices

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    In several scenarios of everyday life, there is a need to communicate orally with other people. However, various technological solutions such as mobile phones cannot be used in places such as meetings, classrooms, or conference rooms without disrupting the activities of people around the speaker. This research develops a tool that enables people to establish a conversation in a public place without disrupting the surrounding environment. To this end, a speech synthesizer is implemented on a personal computer connected to a cell phone, which allows one to establish a mobile call without using the human voice. The speech synthesizer uses the diphone concatenation technique and is developed specifically for the Spanish from Colombia. A mathematical description of the synthesizer shows the decomposition of the synthesizer into various mutually independent processes. Several user-acceptance and quality tests of the obtained signal were performed to evaluate the performance of the tool. The results show a high signal to noise ratio of generated signals and a high intelligibility of the tool
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