bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electromagnetic scattering from perturbed surfaces
Authors: Mitrea Irina , Ott Katharine 
Published: December 2006

AbstractThis paper studies the scattering of electromagnetic waves from a (local) perturbation of a fixed surface, the boundary of a given obstacle in ℝ3. The goal is to produce an algorithm for solving boundary value problems in the exterior of the perturbed domain solely based on the knowledge of the Green function for the original surface. This is done by solving a boundary integral equation which only involves the perturbed portion of the boundary. Copyright © 2006 John Wiley & Sons, Ltd.
The important modes of subsystems: A moment‐matching approach
Authors: Liao Ben‐Shan , Bai Zhaojun , Gao Weiguo 
Published: December 2006

AbstractSubstructure coupling methods, such as the component mode synthesis (CMS) method, have been studied in structural dynamics analysis since 1960s. The modes of subsystems associated with the lowest frequencies are typically retained in these methods. In this paper, we present a coupling‐matrix based mode selection scheme for the CMS method, referred to as the CMSχ method. This new scheme is derived using a moment‐matching principle defined on the interface between substructures. It is compatible to the one in recently proposed optimal modal reduction (OMR) method due to Givoli et al. The improvements of the CMSχ method to the CMS and OMR methods are demonstrated by numerical examples from structural dynamics in both frequency and time domains. Copyright © 2006 John Wiley & Sons, Ltd.
Public thinking about poverty: why it matters and how to measure it
Authors: Bolitho Floyd H. , Carr Stuart C. , Fletcher Richard B. 
Published: December 2006

AbstractMeeting the Millennium Development Goals partly depends on not‐profit organizations raising more funds, which in turn depends on having reliable and valid assessments of where donor and recipient perceptions are out‐of‐line. Across samples from a developed economy Australia (n = 754), and a developing economy Malaŵi (n = 387), we explored the factor structure of the ‘Causes of Third‐World Poverty Questionnaire’ (CTWPQ, D. Harper and colleagues,1990). In addition to four core factors suggested through an original (N = 89) sample from the UK (Blame [1] the Poor, [2] Nature, [3] Third World governments, and [4] International Exploitation), combined Exploratory and Confirmatory Factor Analyses (CFA) differentiate a possible fifth factor germane to the social marketing of aid, blame [5] Conflict. Australians and Malaŵians differed significantly on all five factors, with Malaŵians blaming poverty more on situations and less on the poor themselves, compared to Australian counterparts. Our findings are tentative because the CTWPQ item pool requires expanding to represent underlying constructs more fully. Nonetheless, instruments like the CTWPQ can in future be used to identify and monitor in‐context psychosocial barriers to donation, enabling not‐profit marketing organizations to raise funds more efficiently and effectively.Copyright © 2006 John Wiley & Sons, Ltd.
Interdependent group contingency and mystery motivators to reduce preschool disruptive behavior
Authors: Murphy Kelly A. , Theodore Lea A. , Aloiso Danielle , Alric‐Edwards Jolie M. , Hughes Tammy L. 
Published: December 2006

AbstractChildren exhibiting challenging and disruptive behaviors can require teachers to spend a substantial amount of time on classroom management. Disruptive behaviors in the classroom impact the learning process by taking time away from academic instruction. Further, preschoolers who are disruptive are more likely to continue displaying problematic behaviors throughout the remaining school years. Relative to other age groups, there is a paucity of interventions for preschool children with disruptive behavior. Additionally, children from lower economic backgrounds are at a greater risk for both learning and behavioral problems, as characterized by the preschoolers enrolled in Head Start. Group contingencies are practical, efficient, and teacher‐friendly behavioral interventions that have been employed with older age groups to reduce disruptive behavior. An ABAB reversal design across 9 preschoolers enrolled in a Head Start classroom was employed to assess the effects of an interdependent group contingency with mystery motivators to reduce disruptive classroom behaviors. The present investigation revealed remarkable reductions of disruptive behavior across all 9 participants. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 53–63, 2007.
Bootstrap percolation on the random regular graph
Authors: Balogh József , Pittel Boris G. 
Published: December 2006

AbstractThe k‐parameter bootstrap percolation on a graph is a model of an interacting particle system, which can also be viewed as a variant of a cellular automaton growth process with threshold k ≥ 2. At the start, each of the graph vertices is active with probability p and inactive with probability 1 − p, independently of other vertices. Presence of active vertices triggers a bootstrap percolation process controlled by a recursive rule: an active vertex remains active forever, and a currently inactive vertex becomes active when at least k of its neighbors are active. The basic problem is to identify, for a given graph, p− and p+ such that for p < p− (p > p+ resp.) the probability that all vertices are eventually active is very close to 0 (1 resp.). The bootstrap percolation process is a deterministic process on the space of subsets of the vertex set, which is easy to describe but hard to analyze rigorously in general. We study the percolation on the random d‐regular graph, d ≥ 3, via analysis of the process on the multigraph counterpart of the graph. Here, thanks to a “principle of deferred decisions,” the percolation dynamics is described by a surprisingly simple Markov chain. Its generic state is formed by the counts of currently active and nonactive vertices having various degrees of activation capabilities. We replace the chain by a deterministic dynamical system, and use its integrals to show—via exponential supermartingales—that the percolation process undergoes relatively small fluctuations around the deterministic trajectory. This allows us to show existence of the phase transition within an interval [p−(n),p+(n)], such that (1) p±(n) → p* = 1 − miny∈(0,1)y/ℙ(Bin(d − 1,1 − y) < k); (2) p+(n) − p−(n) is of order n−1/2 for k < d − 1, and n, (εn ↓ 0,εn log n →∞), for k = d − 1. Note that p* is the same as the critical probability of the process on the corresponding infinite regular tree. © 2006 Wiley Periodicals, Inc. Random Struct. Alg., 30, 257–286, 2007
Variation in growth rate in the landsnail Cepaea nemoralis
Authors: Wolda H. 
Published: December 2006

SummaryIn a number of experimental populations of the landsnail Cepaea nemoralis living under natural conditions a variation in growth rate has been observed both within and between populations. Usually it takes two years for newly hatched snails to become adult, but sometimes it takes only one and sometimes three years. The differences between populations had large effects on the differences in number of individuals in these populations.Under experimental conditions in the laboratory it has been shown that there is a large variation in growth rate, part of which is genetic. The genes affecting polymorphism in Cepaea do not seem to be involved in the genetic variation in growth rate. Large eggs produce faster growing juveniles. No effect of the size of the parents on growth rate of the juveniles could be detected. Faster growing snails become larger adults. This may result in faster growing snails having a larger fecundity as larger snails produce on the average more and larger clutches of eggs. Some suggestions were obtained that slow growing individuals have a lower chance of survival.A descriptive model is used to illustrate the increase of complexity of the dynamics of Cepaea populations because of the variation in growth rate.
Examination of the influences of density pressure on the pattern of adult emergence with reference to the azuki bean weevil, Callosobruchus chinensis
Authors: Murai Minoru , Fujii Koichi 
Published: December 2006

SummaryThe effect of competition pressure on the sequential pattern of adult emergence was studied by using the experimental population of the azuki bean weevil. The density and pattern of emergence curves of the parental adult induced the changes in the shape of emergence curve of the progeny as well as the number of progeny individuals. In order to explain these changes, a simple mathematical model which has two independent variables, the population density and the capacity of environment, was introduced. The model generated basically similar patterns of emergene curves as observed in the present experiments. This means that the model displayed well the competition pressure which differentially acted upon early‐born and late‐born individuals in the populations being at different densities and which were differentially received by individual progeny according to the sequential distributions of parents. This different severity of competition pressure resulted in the difference of time when the pressure compelled influences on the sequential distribution of adult emergence. Therefore, early developed individuals may have good chance to survive, but the competition pressure works as a factor modifying their fundamental superiority, especially in the scramble type of competition.Intense crowding of the azuki bean weevil gave rise to the scramble type of competition in the relation between the numbers of adults emerged in two successive generations. When parental emergence concentrated in a short term and at high density, the competition becomes intense, resulting in the inferiority of early developed individuals, in the decrease in number at the next generation and in the increase of duration for emergence.
The statistical and biological implications of sampling units for mountain pine beetle populations in lodgepole pine
Authors: Cole Walter E. 
Published: December 2006

SummaryPopulations of the mountain pine beetle in lodgepole pine were measured using two sample sizes: a single gallery—this is the basic family unit constructed by the parent beetles; and a 6‐ by 6‐inch square area—the bark was removed and the brood counted. Data from the 6‐ by 6‐inch sample were recorded in three ways. Each measurement unit provided different biological information and required different statistical considerations. The single gallery sample provided the most representative data of the entire population, but required additional biological measurement of attack density. The 6‐ by 6‐inch sample brood data taken on an attack density basis provided the most statistically reliable information and encompassed the pertinent biological information. Percent survival, as could be used in elementary life tables, was rather consistent in all measurement units, regardless of point in time of sampling.
Optimal use of patches by parasitoids with a limited fecundity
Authors: Yamada Yoshihiro 
Published: December 2006

Summary
a mathematical model is presented which predicts the expected optimal‐patch‐use strategy for solitary parasitoids with a limited fecundity.
The model predicts that the quality of the patches is determined by the proportion of unparasitized hosts and not by the density of those hosts, and that throughout the searching period the parasitoids should maintain the level of parasitism equal in all the patches irrespective of the host density per patch.
The spatial pattern of parasitism among field patches by a parasitoid with a low fecundity, Praestochrysis shanghaiensis, was in agreement with the prediction of the model, i.e., a similar level of parasitism in different patches was observed when the ratio of female parasitoids to hosts in the whole study area exceeded 0.07. When the ratio was less than 0.05, however, the level of parasitism per patch showed an inverse relation to the host density, and was positively correlated with the female parasitoid‐host ratio.
The model assumes that the parasitoids move between patches without cost and have perfect information about patch quality. Consideration of the cost of moving and sampling bridges the gap between the observed and predicted rates of parasitism found when the female parasitoid‐host ratio in the whole study area was low
Life table studies of the walnut leaf beetle, Gastrolina depressa (Coleoptera: Chrysomelidae), with special attention to aggregation
Authors: Chang Kwang‐Shing , Morimoto Naotake 
Published: December 2006

SummaryIn order to make clear the relationship between the mortality processes and aggregation on the walnut leaf beetle, Gastrolina depressa, life tables of individual colonies were developed and the major mortality factor and the mode of its action were investigated. Furthermore, the influences of the larval colony size on the survival rate and the developmental period were also investigated in the laboratory.In the laboratory, when the larvae were reared on suitable (soft) host plants, the larger the group size, the faster the development. When the larvae were reared on unsuitable (hard) host plants, the larger the group size, the higher the survival rate. In the field, one of the major mortality factors of the egg stage was physiological death. However, there was no particular relation between the egg mass size and hatchability. On the other hand, another mortality factor of eggs, predation by A. hexaspilota, tended to act more on the larger sized egg masses. The mortality of the 1st instar larvae decreased with the increase of colony size. During the larval stages, the major mortality factor was predation by A. hexaspilota and P. japonica. Both predators tended to attack the colony in an all‐or‐none manner. The number of male adults was much less than the number of females in the Ina populations.
Effect of temperature and parasite density on three species of Aphytis (Hymenoptera: Aphelinidae), parasitising California red scale
Authors: Kfir Rami , Podoler Haggai 
Published: December 2006

SummaryThree species of Aphytis parasites of California red scale, Aonidiella aurantii (Maskell) were each confined at different densities with approximately equal numbers of scale insects at several constant temperatures to determine the effect of these factors on progeny production and distribution and the search rate. Egg location on the host body by the parasites was unaffected by temperature or parasite density. A. melinus laid its eggs both dorsally and ventrally in equal proportions while A. lingnanensis and A. chrysomphali laid their eggs ventrally.Progeny production by A. melinus and A. lingnanensis increased at the higher temperature; that of A. chrysomphali did not. Unlike the other species, A. chrysomphali failed to oviposit at 32°C.Although increasing parasite density reduced progeny production in both A. melinus and A. lingnanensis, they were able to maintain an almonst constant search rate. This was due to their ability to distribute their eggs among the hosts more regularly at the higher parasite densities. While the mechanism of this process is easy to understand for A. melinus which behaved as a gregarious parasite, it is unclear for A. lingnanensis, which is almost a solitary parasite. The progeny production and the search rate of A. chrysomphali dropped significantly with increasing parasite density.
Foraging strategy of a non‐omniscient predator in a changing environment (I) model with a data window and absolute criterion
Authors: Inoue Tamiji 
Published: December 2006

Summary
Almost all the models so far presented assume that predators are omniscient in the sense that they always have complete information about the spatial distribution of prey abundance and its change over time. But this type of model cannot cover the situation where the prey abundance in each patch changes over time due to factors other than predation. The model with a data window and absolute criterion (SAC) here enables us to treat such situations.
The strategy of non‐omniscient predators can be generally devided into four procedures; collection of information, its memorization, decision of tactics and its execution. SAC involves only two tactics; to stay another time period in the patch the predator is staying presently or to move to another patch chosen at random. The choice of either one of the two tactics is made by comparing the profitability of the current patch estimated by the data window with a pre‐determined absolute criterion.
Three changing patterns of prey abundance are considered. In the most general pattern good patches have a higher mean profitability than poor patches, but the profitability changes cyclically in each of patches.
There are only two possibilities for an optimal strategy; the “patch choice strategy” in which once the predator has taken a good patch, it tries to stay there even when the state becomes poor, and the ‘state choice strategy” in which the predator seeks for only good states in good patches. The condition for which either of the two foraging strategies is superior to the other is specified analytically.
The process of population increase and patterns of resource utilization of two spider mites, Oligonychus ununguis (Jacobi) and Panonychus citri (McGregor), under experimental conditions (Acari: Tetranychidae)
Authors: Wanibuchi Kyoko , Saitô Yutaka 
Published: December 2006

SummaryPattern of population growth and characteristics of habitat utilization and of migration by two species of spider mites were studied under experimental conditions. The population growth of Oligonychus ununguis (Jacobi) on a chestnut occurred only on a single mite‐release leaf over a long period, and few individuals moved away. Most of the 2nd progeny generation females of this species emigrated from the mite‐release leaf as well as the sapling by means of ballooning threads. During this growth period, population density on the mite‐release leaf levelled off, whereas that on the sapling increased. In contrast, the foundress of Panonychus citri (McGregor) on citrus actively moved over several neighbouring leaves, and until the 2nd progeny generation females emerged, individuals were distributed over all the sapling leaves by means of walking. Emigration from the sapling was not observed until the 2nd progeny females emerged, and after that the mites emigrated by means of ballooning threads. The population density of P. citri on the sapling levelled off and was rather decreased on the mite‐release leaf at the time of mite emigration. Comparing the changing pattern of the relative degree of aggregation (m*/m) measured in two different units between these two species, the pattern of m*/m in 1 cm2 on the mite release leaf in O. ununguis resembled that of the unit of leaves on the sapling in P. citri. This result as well as behavioural observations indicate that migration of O. ununguis is the movement from leaf to leaf and that of P. citri from sapling to sapling. It is, therefore, concluded that the boundary of the microhabitat is a single leaf for O. ununguis but sapling or foliage for P. citri.
Economy of food utilization in a gregarious sawfly, Arge nigrinodosa Motschulsky (Hymenoptera: Argidae): Relative abundance of food in the natural habitat and behavioral pattern of larval feeding
Authors: Adachi Ishizue 
Published: December 2006

SummaryRelative abundance of natural food resource, leaves of wild rose, of Arge migrinodosa was evaluated by comparing the food quantity which the larvae composing a colony utilized throughout the larval stage with that which is available in the habitat. In this connection, behavioral pattern of larval feeding was also observed under natural conditions, and its ecological significance was discussed.It was quantitatively clarified that the larvae faced the severe shortage of food and had to disperse to other shoots with the expense of probably high risk. Under pressures of such insufficient supply of food, the larvae follow the most efficient pattern of feeding behavior that they move to the tip of shoot at first and feed regularly downward thereafter. Though individual larvae behaved completely independently of each other, the aggregation appeared to be formed and maintained because all the larvae from the same egg mass follow this fixed feeding pattern.
Long‐chain polyunsaturated fatty acids in plasma lipids of obese children
Authors: Decsi Tamás , Molnár Dénes , Koletzko Berthold 
Published: December 2006

AbstractFatty acid composition of plasma phospholipids (PL), triglycerides (TG), and sterol esters (STE) was determined by high‐resolution capillary gas‐liquid chromatography in 22 obese children (age: 13.7±1.4 y, body weight relative to normal weight for height: 170±24%, mean ±SD) and compared with data obtained in 25 age‐matched healthy controls. There were no differences in the levels of linoleic acid (LA, C18∶2n‐6) in any of the plasma fractions from the obese children and the controls. Obese children exhibited significantly higher values of arachidonic acid (AA, C20∶4n‐6) than controls both in PL (12.6 [2.4] vs. 8.3 [1.4], % wt/wt, [median (interquartile range)],P<0.001) and STE (7.3 [1.8] vs. 6.0 [1.1],P<0.05). Similarly, obese children showed higher values than controls for dihomo‐γ‐linolenic acid (DHGLA, C20∶3n‐6) in PL (4.0 [0.5] vs. 3.0 [0.6],P<0.001), TG (0.4 [0.1] vs. 0.2 [0.1],P<0.001), and STE (0.9 [0.1] vs. 0.7 [0.1],P<0.01), and for γ‐linolenic acid (C18∶3n‐6) in STE (1.1 [0.2] vs. 0.8 [0.2],P<0.001). The AA/LA ratios were higher in obese children than in controls in PL (0.68 [0.16] vs. 0.42 [0.09],P<0.0005) and STE (0.16 [0.04] vs. 0.12 [0.02],P<0.05), whereas the AA/DHGLA ratios were lower in TG of obese children than in controls (3.40 [0.64] vs. 5.10 [1.75],P<0.005). Plasma glucose concentrations were inversely related to AA in TG (r=0.53,P<0.05), and plasma TG concentrations were inversely related to AA in PL and STE (r=−0.49,P<0.05 andr=−0.48,P<0.05) and to the AA/DHGLA ratios in PL (r=−0.57,P<0.01),TG (r=−0.56,P<0.01) and STE (r=−0.56,P<0.01). We conclude that the significantly higher values of n‐6 long‐chain polyunsaturated fatty acids (LCP) in plasma lipids of obese children than in age‐matched controls may be caused by an enhanced activity of Δ6‐desaturation, and we speculate that elevated fasting immunoreactive insulin seen in obese children (19.4±8.0 μU/mL) may stimulate synthesis of n‐6 LCP fatty acids.