170 research outputs found

    Phase rigidity and avoided level crossings in the complex energy plane

    Get PDF
    We consider the effective Hamiltonian of an open quantum system, its biorthogonal eigenfunctions ϕλ\phi_\lambda and define the value rλ=(ϕλϕλ)/r_\lambda = (\phi_\lambda|\phi_\lambda)/ that characterizes the phase rigidity of the eigenfunctions ϕλ\phi_\lambda. In the scenario with avoided level crossings, rλr_\lambda varies between 1 and 0 due to the mutual influence of neighboring resonances. The variation of rλr_\lambda may be considered as an internal property of an {\it open} quantum system. In the literature, the phase rigidity ρ\rho of the scattering wave function ΨCE\Psi^E_C is considered. Since ΨCE\Psi^E_C can be represented in the interior of the system by the ϕλ\phi_\lambda, the phase rigidity ρ\rho of the ΨCE\Psi^E_C is related to the rλr_\lambda and therefore also to the mutual influence of neighboring resonances. As a consequence, the reduction of the phase rigidity ρ\rho to values smaller than 1 should be considered, at least partly, as an internal property of an open quantum system in the overlapping regime. The relation to measurable values such as the transmission through a quantum dot, follows from the fact that the transmission is, in any case, resonant with respect to the effective Hamiltonian. We illustrate the relation between phase rigidity ρ\rho and transmission numerically for small open cavities.Comment: 6 pages, 3 figure

    Evaluating the Perception and Awareness of Patients Regarding Ovarian Cysts in Peshawar, Pakistan

    Get PDF
    Purpose: To evaluate patients’ perception regarding ovarian cyst as well as their awareness of the symptoms and health management of the disease.Methods: A quantitative research approach was used to conduct this study. Patients were selected from the Gynecology wards, Hayatabad Medical Complex, Peshawar and a questionnaire was designed to evaluate the patients’ knowledge and awareness.Results: When women were asked if they had prior knowledge about the ovarian cyst, 37 (58.7 %) responded that they were first told by the  physician during their visit to the clinic or hospital while the patients  responded, “Still don’t know” are 22 (34.9 %). With respect to educational level of the patients, they seemed to be less aware of the disease. Their perception regarding the disease is that they had a “water filled” balloon or tumor.Conclusion: Prior to discharge of an ovarian cyst patient from the hospital, she should be counseled on the disease and successful treatment outcomes. Counseling of the patients may result in compliance with therapy, good quality of life and lower economic burden.Keywords: Ovarian cyst, Menstrual cycle, Awareness, Perception, Treatment outcome

    S-matrix theory for transmission through billiards in tight-binding approach

    Full text link
    In the tight-binding approximation we consider multi-channel transmission through a billiard coupled to leads. Following Dittes we derive the coupling matrix, the scattering matrix and the effective Hamiltonian, but take into account the energy restriction of the conductance band. The complex eigenvalues of the effective Hamiltonian define the poles of the scattering matrix. For some simple cases, we present exact values for the poles. We derive also the condition for the appearance of double poles.Comment: 29 pages, 9 figures, submitted to J. Phys. A: Math. and Ge

    PENGARUH PORITABILITAS DAN LEVERAGE TERHADAP TAX AVOIDANCE (Studi pada Perusahaan Manufaktur Sektor Otomotif dan Komponen yang Terdaftar di Bursa Efek Indonesia Periode 2013-2017 )

    Get PDF
    v ABSTRAK Penelitian ini bertujuan untuk memberikan gambaran tentang tax avoidance perusahaan otomotif dan komponen di Indonesia dan mengetahui pengaruh profitabilitas, dan leverage terhadap tax avoidance. Operasional variabel yang digunakan dalam penelitian ini adalah variabel profitabilitas, dan leverage. Sedangkan variabel terikat yaitu tax avoidance. Metode penelitian yang digunakan adalah metode deskriptif dan verifikatif. Populasi dari penelitian ini adalah semua perusahaan otomotif dan komponen yang terdaftar di Bursa Efek Indonesia tahun 2013-2017. Metode pemilihan sampel penelitian ini menggunakan teknik purposive sampling dengan total 7 perusahaan yang memenuhi kriteria. Analisis data dengan menggunakan analisis regresi linier berganda. Hasil penelitian menunjukkan bahwa Profitabilitas berpengaruh signifikan terhadap Tax avoidance dengan kontribusi 37.2%, Leverage secara parsial berpengaruh signifikan terhadap Tax Avoidance dengan kontribusi 31.8%. Kata Kunci : Profitabilitas, Leverage dan, Tax Avoidance

    Distribution of nearest distances between nodal points for the Berry function in two dimensions

    Full text link
    According to Berry a wave-chaotic state may be viewed as a superposition of monochromatic plane waves with random phases and amplitudes. Here we consider the distribution of nodal points associated with this state. Using the property that both the real and imaginary parts of the wave function are random Gaussian fields we analyze the correlation function and densities of the nodal points. Using two approaches (the Poisson and Bernoulli) we derive the distribution of nearest neighbor separations. Furthermore the distribution functions for nodal points with specific chirality are found. Comparison is made with results from from numerical calculations for the Berry wave function.Comment: 11 pages, 7 figure

    The impact of relative position and returns on sacrifice and reciprocity: an experimental study using individual decisions

    Get PDF
    We present a comprehensive experimental design that makes it possible to characterize other-regarding preferences and their relationship to the decision maker’s relative position. Participants are faced with a large number of decisions involving variations in the trade-offs between own and other’s payoffs, as well as in other potentially important factors like the decision maker’s relative position. We find that: (1) choices are responsive to the cost of helping and hurting others; (2) The weight a decision maker places on others’ monetary payoffs depends on whether the decision maker is in an advantageous or disadvantageous relative position; and (3) We find no evidence of reciprocity of the type linked to menu-dependence. The results of a mixture-model estimation show considerable heterogeneity in subjects’ motivations and confirm the absence of reciprocal motives. Pure selfish behavior is the most frequently observed behavior. Among the subjects exhibiting social preferences, social-welfare maximization is the most frequent, followed by inequality-aversion and by competitiveness

    An ex-post view of inequality of opportunity in France and its regions

    Get PDF
    This paper proposes an ex-post measure of inequality of opportunity in France and its regions by assessing the inequality between individuals exerting the same effort. To this end, we define a fair income that fulfils ex-post equality of opportunity requirements. Unfairness is measured by an unfair Gini based on the distance between the actual income and the fair income. Our findings reveal that the measures of ex-post inequality of opportunity largely vary across regions, and that this is due to di_erences in reward schemes and in the impact of the non responsibility factors of income. We find that most regions have actual incomes closer to fair incomes than to average income, excepted Ile de France where the actual income looks poorly related to effort variables. Finally, we find that income inequality and inequality of opportunity are positively correlated among regions

    Benzyl Isothiocyanate, a Major Component from the Roots of Salvadora Persica Is Highly Active against Gram-Negative Bacteria

    Get PDF
    Plants produce a number of antimicrobial substances and the roots of the shrub Salvadora persica have been demonstrated to possess antimicrobial activity. Sticks from the roots of S. persica, Miswak sticks, have been used for centuries as a traditional method of cleaning teeth. Diverging reports on the chemical nature and antimicrobial repertoire of the chewing sticks from S. persica led us to explore its antibacterial properties against a panel of pathogenic or commensal bacteria and to identify the antibacterial component/s by methodical chemical characterization. S. persica root essential oil was prepared by steam distillation and solid-phase microextraction was used to sample volatiles released from fresh root. The active compound was identified by gas chromatography-mass spectrometry and antibacterial assays. The antibacterial compound was isolated using medium-pressure liquid chromatography. Transmission electron microscopy was used to visualize the effect on bacterial cells. The main antibacterial component of both S. persica root extracts and volatiles was benzyl isothiocyanate. Root extracts as well as commercial synthetic benzyl isothiocyanate exhibited rapid and strong bactericidal effect against oral pathogens involved in periodontal disease as well as against other Gram-negative bacteria, while Gram-positive bacteria mainly displayed growth inhibition or remained unaffected. The short exposure needed to obtain bactericidal effect implies that the chewing sticks and the essential oil may have a specific role in treatment of periodontal disease in reducing Gram-negative periodontal pathogens. Our results indicate the need for further investigation into the mechanism of the specific killing of Gram-negative bacteria by S. persica root stick extracts and its active component benzyl isothiocyanate

    Worker remittances and the global preconditions of ‘smart development’

    Get PDF
    With the growing environmental crisis affecting our globe, ideas to weigh economic or social progress by the ‘energy input’ necessary to achieve it are increasingly gaining acceptance. This question is intriguing and is being dealt with by a growing number of studies, focusing on the environmental price of human progress. Even more intriguing, however, is the question of which factors of social organization contribute to a responsible use of the resources of our planet to achieve a given social result (‘smart development’). In this essay, we present the first systematic study on how migration – or rather, more concretely, received worker remittances per GDP – helps the nations of our globe to enjoy social and economic progress at a relatively small environmental price. We look at the effects of migration on the balance sheets of societal accounting, based on the ‘ecological price’ of the combined performance of democracy, economic growth, gender equality, human development, research and development, and social cohesion. Feminism in power, economic freedom, population density, the UNDP education index as well as the receipt of worker remittances all significantly contribute towards a ‘smart overall development’, while high military expenditures and a high world economic openness are a bottleneck for ‘smart overall development’
    corecore