Resistance and Synergism of Insecticides in Diamondback Moth, Plutella Xylostella (Lepidoptera : Yponomeutidae)

A leaf-dipped bioassay was conducted to evaluate the toxicity of insecticides cypermethrin, permethrin, fipronil, avermectin b1 and emamectin benzoate against two lowland (Karak & Cheng strain) and a susceptible strains of diamondback moth (DBM). The synergistic effect of piperonyl butoxide (PBO), S,S,8- tributylphosphorotrithioate (DEF) and maleic acid diethyl ester (MADE) on the toxicity of the insecticides tested were also conducted by the combined leafdipped/topical bioassay. Both the lowland strains showed high LC50 values (> Ug/mL) for cypermethrin and permethrin. Based on the LC50 values, toxicities of the insecticides tested in decreasing order for the Karak and Cheng strains were : emamectin benzoate> avermectin b] > fipronil > permethrin > cypermethrin. The most toxic insecticide was emamectin benzoate with LC50 value of 1.62 X 10-5mg/L and 1.59 X 10-5mg/L for Cheng and Karak strain respectively. The slope of the concentration-mortality line indicated that both field-collected strains gave homogenous response towards the cypermethrin and permethrin but not the newer insecticides. The results also showed that the DBM developed high level of resistance toward cypermethrin and permethrin. Cheng strain showed a higher resistance ratio for fipronil compared with the Karak strain. In synergism study, cypermethrin was highly synergised by PBO compared to other insecticides tested. Cypermethrin was synergised 19.8-fold and 12.6-fold for Karak and Cheng strain respectively. Both DEF and MADE showed little synergistic effects to the insecticides tested with synergistic ratio of less than 3-fold for both Cheng and Karak strain respectively. The results suggested that microsomal monooxygenases played an important role in the detoxification metabolism of cypermethrin in both strains of DBM. Esterases and glutathione s-ttansferases, however, played a minor role in the metabolism of the insecticides for both strains of DBM

The covering radius problem for sets of perfect matchings

Consider the family of all perfect matchings of the complete graph $K_{2n}$ with $2n$ vertices. Given any collection $\mathcal M$ of perfect matchings of size $s$, there exists a maximum number $f(n,x)$ such that if $s\leq f(n,x)$, then there exists a perfect matching that agrees with each perfect matching in $\mathcal M$ in at most $x-1$ edges. We use probabilistic arguments to give several lower bounds for $f(n,x)$. We also apply the Lov\'asz local lemma to find a function $g(n,x)$ such that if each edge appears at most $g(n, x)$ times then there exists a perfect matching that agrees with each perfect matching in $\mathcal M$ in at most $x-1$ edges. This is an analogue of an extremal result vis-\'a-vis the covering radius of sets of permutations, which was studied by Cameron and Wanless (cf. \cite{cameron}), and Keevash and Ku (cf. \cite{ku}). We also conclude with a conjecture of a more general problem in hypergraph matchings.Comment: 10 page

Some Blow-Up Problems for a Semilinear Parabolic Equation with a Potential

The blow-up rate estimate for the solution to a semilinear parabolic equation $u_t=\Delta u+V(x) |u|^{p-1}u$ in $\Omega \times (0,T)$ with 0-Dirichlet boundary condition is obtained. As an application, it is shown that the asymptotic behavior of blow-up time and blow-up set of the problem with nonnegative initial data u(x,0)=M\vf (x) as $M$ goes to infinity, which have been found in \cite{cer}, are improved under some reasonable and weaker conditions compared with \cite{cer}.Comment: 29 page

MASJID CHENG HOO SURABAYASENI BANGUNAN, ORNAMEN, DAN KALIGRAFI

Penyebaran agama Islam di Nusantara terjadi karena efek samping dari perdagangan, lembaga pendidikan, dan perkawinan yang dilakukan para pendatang dari Arab, Gujarat, dan Cina. Kedatangan Laksamana Cheng Hoo beserta armada kapalnya dari Cina yang singgah di Indonesia memberikan pengaruh penyebaran agama Islam dan budaya Tiongkok. Masyarakat Indonesia kini mayoritas memeluk dan mempelajari agama Islam, dan membangun masjid sebagai tempat beribadah dan lembaga peradaban dan budaya masyarakat Islam, di masjid umat muslim beribadah bersama, akan tetapi pada Al Quran dan Assunah tidak terdapat aturan-aturan yang mengungkapkan secara detail dan jelas bentuk bangunan. PITI (Pembina Iman Tauhid Islam) di Surabaya membangun Masjid Cheng Hoo untuk mengenang Laksamana Cheng Hoo yang membawa pengaruh Islam dan budaya Tiongkok. Karena latar belakang tersebut, masalah yang dikaji dalam penelitian. (1) bagaimana seni bangunan dari Masjid Cheng Hoo Surabaya, (2) bagaimana ornamen Masjid Cheng Hoo Surabaya, (3)bagaimana kaligrafi Masjid Cheng Hoo Surabaya. Metode kualitatif digunakan sebagai dasar penelitian dengan rancangan deskriptif untuk mendeskripsikan seni bangunan, ornamen, dan kaligrafi yang terdapat pada Masjid Cheng Hoo Surabaya, dengan teknik pengumpulan data menggunakan teknik observasi, wawancara, dan dokumentasi. Hasil penelitian mengetahui bahwa masjid yang menyerupai tempat ibadah Tri Dharma dibangun untuk mengenang Laksamana Cheng Hoo. Kombinasi kehadiran budaya Cina dan elemen Islam dalam seni bangunan, ornamen masjid dalam bentuk lukisan dan ukiran atau cetakan di lantai, pintu, jendela, dinding, kuda-kuda, dan langit-langit. Gaya kaligrafi Islam di Masjid Cheng Hoo seperti gaya kaligrafi Raihani masjid pada umumnya. Terdapat keunikan pada dinding yang ditimbulkan oleh gaya kaligrafi Raihani dikombinasikan dengan jendela melingkar seperti bangunan Cina dan terbuat dari besi. Pada papan masjid terdapat gaya kaligrafi Cina: Cursive Script (xingshu).Kata Kunci: Masjid Cheng Hoo, ornamen, kaligrafi, dan seni bangunan.The spread of Islam in the archipelago occur due to the side effects of commerce, educational institutions, and marriages were performed migrants from Arab, Gujarat, and China. The arrival of Admiral Cheng Hoo along with a fleet of ships from China were stopped in Indonesia gives influence the spread of Islam and the culture of China. Indonesia is now the majority society and learn to embrace Islam, and to build a mosque as a place of worship and institutions of civilization and culture of Islamic societies, in the mosque Muslims worship together. But the Quran and Assunah there are no rules in detail and clearly reveal the shape of the building. PITI (Trustees of Tawheed Islamic Faith) in Surabaya build Cheng Hoo Mosque to commemorate Admiral Cheng Hoo who brought Islam and the influence of Chinese culture. Because of this background, issues examined in the study. (1) How is the art of building Cheng Hoo Mosque Surabaya. (2) How is the ornaments Cheng Hoo Mosque Surabaya. (3) How is the calligraphy Cheng Hoo Mosque Surabaya. Qualitative methods are used as a basis to draft a descriptive study to describe the art of building, ornament, and calligraphy found in Cheng Hoo Mosque, with data collection techniques using observation, interviews, and documentation. Results of this study, researchers knew that mosque resembles Tri Dharma place of worship was built in memory of Admiral Cheng Hoo. The presence combination of Chinese culture and Islamic elements in the art of building, mosque’s ornament in the form of paintings and carvings or mold on the floors, doors, windows, walls, easels, and ceiling. Islamic calligraphy style at Cheng Hoo Mosque like the style of calligraphy Raihani most mosques in general. On the wall there is a uniqueness posed by Rihani calligraphic style combined with a circular window looks like the Chinese buildings and made of iron. On board mosque there is also Chinese calligraphy-style: Cursive Script (xingshu).Keywords: Cheng Hoo Mosque, ornament, calligraphy, and architectur

g1(x) and g2(x) in the Meson Cloud Model

We calculate the spin dependent structure functions g1(x) and g2(x) of the proton and neutron. Our calculation uses the meson cloud model of nucleon structure and includes the effects of kinematic terms which mix transverse and longitudinal spin components. We find small corrections to the nucleon structure functions, however these are significant for the neutron.Comment: 4 pages, contribution to DIS 05, Madison, Wisconsi

Fast integral equation methods for the modified Helmholtz equation

We present a collection of integral equation methods for the solution to the two-dimensional, modified Helmholtz equation, u(\x) - \alpha^2 \Delta u(\x) = 0, in bounded or unbounded multiply-connected domains. We consider both Dirichlet and Neumann problems. We derive well-conditioned Fredholm integral equations of the second kind, which are discretized using high-order, hybrid Gauss-trapezoid rules. Our fast multipole-based iterative solution procedure requires only O(N) or $O(N\log N)$ operations, where N is the number of nodes in the discretization of the boundary. We demonstrate the performance of the methods on several numerical examples.Comment: Published in Computers & Mathematics with Application