4,783 research outputs found

    The Effect of Rekattidiri Ovitrap Towards Aedes Aegypti Larval Density

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    Dengue Hemorrhagic Fever (DHF) is a health problem in Indonesia. The entire region of Indonesia at risk of contracting dengue disease. The study aims to prove the effect of modifications ovitrap rekattidiri on the density of larvae (HI: House Index, CI: Container Index and BI: Breteu Index) as well as comparing the differences between the mean larvae trapped between ovitrap Rekattidiri with standard ovitrap. Using a quasi experimental design, time series experimental design with Control group. Population subjects were Aedes aegypti at the endemic sites in Pontianak, West Borneo. The results showed larval density index in the intervention area decreased each ie HI from 26% to 3%, CI of 6.95% to 2.19 %, and BI from 29% to 13%. The number of larvae trapped in ovitrap rekattidiri ie 70% (12,770 larvae) more than the standard ovitrap in the control and intervention, namely: 17% (3,057 larvae) and 13% (2,334 larvae). It is concluded that there are significant modifications Rekattidiri ovitrap against larval density index (HI p-value: 0.025, CI p-value: 0.052, BI value of p: 0.04) and there are differences between the mean larvae trapped in ovitrap Rekattidiri and standard ovitrap with p value: 0.001

    A bound for the eigenvalue counting function for Krein--von Neumann and Friedrichs extensions

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    For an arbitrary open, nonempty, bounded set Ω⊂Rn\Omega \subset \mathbb{R}^n, n∈Nn \in \mathbb{N}, and sufficiently smooth coefficients a,b,qa,b,q, we consider the closed, strictly positive, higher-order differential operator AΩ,2m(a,b,q)A_{\Omega, 2m} (a,b,q) in L2(Ω)L^2(\Omega) defined on W02m,2(Ω)W_0^{2m,2}(\Omega), associated with the higher-order differential expression τ2m(a,b,q):=(∑j,k=1n(−i∂j−bj)aj,k(−i∂k−bk)+q)m,m∈N, \tau_{2m} (a,b,q) := \bigg(\sum_{j,k=1}^{n} (-i \partial_j - b_j) a_{j,k} (-i \partial_k - b_k)+q\bigg)^m, \quad m \in \mathbb{N}, and its Krein--von Neumann extension AK,Ω,2m(a,b,q)A_{K, \Omega, 2m} (a,b,q) in L2(Ω)L^2(\Omega). Denoting by N(λ;AK,Ω,2m(a,b,q))N(\lambda; A_{K, \Omega, 2m} (a,b,q)), λ>0\lambda > 0, the eigenvalue counting function corresponding to the strictly positive eigenvalues of AK,Ω,2m(a,b,q)A_{K, \Omega, 2m} (a,b,q), we derive the bound N(λ;AK,Ω,2m(a,b,q))≤Cvn(2π)−n(1+2m2m+n)n/(2m)λn/(2m),λ>0, N(\lambda; A_{K, \Omega, 2m} (a,b,q)) \leq C v_n (2\pi)^{-n} \bigg(1+\frac{2m}{2m+n}\bigg)^{n/(2m)} \lambda^{n/(2m)} , \quad \lambda > 0, where C=C(a,b,q,Ω)>0C = C(a,b,q,\Omega)>0 (with C(In,0,0,Ω)=∣Ω∣C(I_n,0,0,\Omega) = |\Omega|) is connected to the eigenfunction expansion of the self-adjoint operator A~2m(a,b,q)\widetilde A_{2m} (a,b,q) in L2(Rn)L^2(\mathbb{R}^n) defined on W2m,2(Rn)W^{2m,2}(\mathbb{R}^n), corresponding to τ2m(a,b,q)\tau_{2m} (a,b,q). Here vn:=πn/2/Γ((n+2)/2)v_n := \pi^{n/2}/\Gamma((n+2)/2) denotes the (Euclidean) volume of the unit ball in Rn\mathbb{R}^n. Our method of proof relies on variational considerations exploiting the fundamental link between the Krein--von Neumann extension and an underlying abstract buckling problem, and on the distorted Fourier transform defined in terms of the eigenfunction transform of A~2(a,b,q)\widetilde A_{2} (a,b,q) in L2(Rn)L^2(\mathbb{R}^n). We also consider the analogous bound for the eigenvalue counting function for the Friedrichs extension AF,Ω,2m(a,b,q)A_{F,\Omega, 2m} (a,b,q) in L2(Ω)L^2(\Omega) of AΩ,2m(a,b,q)A_{\Omega, 2m} (a,b,q). No assumptions on the boundary ∂Ω\partial \Omega of Ω\Omega are made.Comment: 39 pages. arXiv admin note: substantial text overlap with arXiv:1403.373

    Network constraints on learnability of probabilistic motor sequences

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    Human learners are adept at grasping the complex relationships underlying incoming sequential input. In the present work, we formalize complex relationships as graph structures derived from temporal associations in motor sequences. Next, we explore the extent to which learners are sensitive to key variations in the topological properties inherent to those graph structures. Participants performed a probabilistic motor sequence task in which the order of button presses was determined by the traversal of graphs with modular, lattice-like, or random organization. Graph nodes each represented a unique button press and edges represented a transition between button presses. Results indicate that learning, indexed here by participants' response times, was strongly mediated by the graph's meso-scale organization, with modular graphs being associated with shorter response times than random and lattice graphs. Moreover, variations in a node's number of connections (degree) and a node's role in mediating long-distance communication (betweenness centrality) impacted graph learning, even after accounting for level of practice on that node. These results demonstrate that the graph architecture underlying temporal sequences of stimuli fundamentally constrains learning, and moreover that tools from network science provide a valuable framework for assessing how learners encode complex, temporally structured information.Comment: 29 pages, 4 figure
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