Results 31 to 40 of about 285,691 (303)
PLoS ONE, 2021 IntroductionOpen Doors, an HIV prevention project targeting key populations in Zambia, recorded low HIV positivity rates (9%) among HIV testing clients, compared to national adult prevalence (12.3%), suggesting case finding efficiency could be improved ...
Joseph Kamanga +9 more
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Combinatorics and total positivity
Journal of Combinatorial Theory, Series A, 1995 An infinite real matrix \(M\) is said to be totally positive (TP) if every minor of \(M\) has nonnegative determinant. The purpose of the article is to show that many familiar matrices arising in combinatorics and the theory of symmetrical functions have this property.
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MathematicsGeneralized order statistics (GOSs) are often adopted as a tool for providing a unified approach to several stochastic models dealing with ordered random variables. In this contribution, we first recall various useful results based on the notion of total
Maryam Esna-Ashari +3 more
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Epidemiological characteristics of four common respiratory viral infections in children
Virology Journal, 2021 Background Viruses are the main infectious agents of acute respiratory infections in children. We aim to describe the epidemiological characteristics of viral pathogens of acute respiratory tract infections in outpatient children. Methods From April 2018
Guohong Zhu +6 more
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Total Positivity in Symmetric Spaces
Representation Theory, 2022 In this paper we extend the theory of total positivity for reductive groups to the case of symmetric spaces.
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Determinantal criteria for total positivity [PDF]
, 2001 A matrix is totally positive (respectively, strictly totally positive) if all its minors are nonnegative (respectively, positive). In this paper, we revisit the main determinantal criteria for these matrices and provide two new ones: one of them for the ...
J.M. Peña, Peña, J.M.
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Strictly Totally Positive Systems
Journal of Approximation Theory, 1998 Let \(F(A)\) denote the set of all real-valued functions defined on \(A\subset \mathbb{R}\). A system \(U_n= \{u_0, \dots, u_n\} \subset F(A)\), is called a \(T\)-system if Cardinal \(A \geq n+1\), the functions in \(U_n\) are linearly independent on \(A\), and all the determinants of the square collocation matrices \[ M{u_0, \dots, u_n \choose t_0 ...
Carnicer, J.M., Peña, J.M., Zalik, R.A.
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Total positivity of Narayana matrices [PDF]
Discrete Mathematics, 2018 We prove the total positivity of the Narayana triangles of type $A$ and type $B$, and thus affirmatively confirm a conjecture of Chen, Liang and Wang and a conjecture of Pan and Zeng. We also prove the strict total positivity of the Narayana squares of type $A$ and type $B$.
Yi Wang 0027, Arthur L. B. Yang
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On the total—and strict total—Positivity of the kernels associated with parabolic initial boundary value problems [PDF]
, 1986 This paper is concerned with the total—and strict total—positivity of the integral kernels which relate the solutions of parabolic initial boundary value problems to the initial and boundary data.
E.J.P.Georg Schmidt +1 more
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Monotonic Random Variables According to a Direction
AxiomsIn this paper, we introduce the concept of monotonicity according to a direction for a set of random variables. This concept extends well-known multivariate dependence notions, such as corner set monotonicity, and can be used to detect dependence in ...
José Juan Quesada-Molina +1 more
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