bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of a community‐based literacy program on young children's language and conceptual development
Authors: Cronan Terry A. , Cruz Sonia G. , Arriaga Rosa I. , Sarkin Andrew J. 
Published: October 2006

AbstractEffects of a community‐based literacy program on 1−, 2−, and 3‐year‐old children's language and conceptual development were assessed. University students were trained to teach Head Start parents effective methods for reading to their children. Families were randomly assigned to receive 18, 3, or 0 instructional visits. Results indicated that parents in the 18‐instructional‐visit program increased their participation in appropriate literacy behaviors such as reading to their children, teaching concepts to their children, and using the library, more than parents in the 0‐instructional‐visit groups. Children in the 18‐instructional‐visit program showed greater gains in language and conceptual development than children in the 0‐instructional‐visit group. Few differences were found between children in the 3‐visti and 0‐instructional‐visit groups. Thus, only a high‐intensity community‐based intervention designed to train parents was effective in increasing emergent literacy in low‐income ethnic children.
Regulatory processes and population cyclicity in laboratory populations of Anagasta kühniella (Zeller) (Lepidoptera: Phycitidae)
Authors: Matsumoto B. M. , Huffaker C. B. 
Published: October 2006

SummaryAsMatsumoto andHuffaker (1973) concluded that their initial universe size was too small for the proper separation of the effects of host density and dispersion on parasite performance, a larger universe of 38 1/2″ (length) ×38 1/2″ (width) ×3″ (height) was used.When individual parasites were exposed to fixed densities and dispersion patterns of host, they displayed an overall decrease in the parasitization rate when compared to the small universe. In all cases aHolling‐type response resulted.When a group of 10 parasites per test was employed a Nicholsonian type of response resulted.In an experimentally confined space, the parasites displayed a mutual behavioral interference resulting in emigration which accelerated as the parasite density increased.
A stochastic computer model for simulating population growth
Authors: Sonleitner Frank J. 
Published: October 2006

SummaryA model is described for investigating the interactions of age‐specific birth and death rates, age distribution and density‐governing factors determining the growth form of single‐species populations. It employs Monte Carlo techniques to simulate the births and deaths of individuals while density‐governing factors are represented by simple algebraic equations relating survival and fecundity to population density. In all respects the model's behavior agrees with the results of more conventional mathematical approaches, including the logistic model andLotka's Law, which predicts a relationship betwen age‐specific rates, rate of increase and age distribution.Situations involving exponential growth, three different age‐independent density functions affecting survival, three affecting fecundity and their nine combinations were tested. The one function meeting the assumptions of the logistic model produced a logistic growth curve embodying the correct values or rm and K. The others generated sigmoid curves to which arbitrary logistic curves could be fitted with varying success. Because of populational time lags, two of the functions affecting fecundity produced overshoots and damped oscillations during the initial approach to the steady state.The general behavior of age‐dependent density functions is briefly explored and a complex example is described that produces population fluctuations by an egg cannibalism mechanism similar to that found in the flour beetle Tribolium.The model is free of inherent time lags found in other discrete time models yet these may be easily introduced. Because it manipulates separate individuals, the model may be combined readily with the Monte Carlo simulation models of population genetics to study eco‐genetic phenomena.
The role of medium conditioning in the population dynamics of the housefly
Authors: Bryant Edwin H. , Hall Augusta E. 
Published: October 2006

SummaryThe role of larval medium conditioning on the behavior of larvae and of ovipositing adults of the housefly, Musca domestica L., was investigated through behavioral preference tests. Larvae were strongly attracted to medium conditioned by themselves or other larvae, while adult females overwhelmingly oviposited in fresh medium. Medium conditioning occurs within a few hours after hatching of an egg cohort and is effective in preventing overcrowding of a single site by shutting off further oviposition within 24 hours after eggs are initially deposited. A model of medium conditioning optimizes density for developing larvae and could also provide for regulation of local larval populations.
A computer simulation of the epidemiology of the rice dwarf virus
Authors: Nakasuji Fusao , Kiritani Keizi , Tomida Eishi 
Published: October 2006

SummaryAn epidemiological system model was developed to evaluate the role of factors which were responsible for the prevalence of rice dwarf virus (RDV) transmitted by the green rice leafhopper, Nephotettix cincticeps. Simulation tests were conducted by varying values of the following three parameters: the vector density, the coefficient of the efficiency of feeding acquisition of RDV of the vector, and that of efficiency of RDV transmission by the vector. The effect of each parameter was assessed in terms of changes in percentages of infected insects and of infected rice hills.Both the percentages of infected insects and of infected rice hills increased rapidly with increasing vector density within a range of low vector density. The former increased linearly when the acquisitive coefficient was increased. But the percentage of infected rice hills was affected to a lesser extent. The percentage of infected insects and that of infected rice hills increased exponentially with increasing values of the transmission coefficient. The results obtained from the simulation tests were discussed in relation to the ecological factors which caused the recent prevalence of RDV.
Estimating the survival rate and mean longevity for adults in a field population of the green rice leafhopper, Nephotettix cincticepsUhler, by the application ofHokyo andKiritani's method
Authors: Hokyo Nobuhiko , Kuno Eizi 
Published: October 2006

SummaryApplication of the female dissection method proposed byHokyo andKiritani (1967) was attempted in both 1968 and 1969 to estimate the daily survival rate and the mean longevity for the adult population of the green rice leafhopper, Nephotettix cincticeps, in a paddy field. The estimated mean longevity for females was far shorter than the physiological longevity of this species, ranging from 4 to 7 days with some variation between different generations. This could explain the remarkable discontinuity among successive generations which proved to form an important feature of the pattern of seasonal population changes of this insect. Between the two years, the estimated survival rate (and hence the mean longevity also) was negatively correlated to the estimated population size of adults that emerged in either of the two successive generations. This apparent density dependence suggests the possibility that the adult survival, including the effect of dispersal, plays some critical role in bringing about the remarkable population stability from year to year shown by the field population of N. cincticeps.
A field study of the effect of prebaiting on censusing by the capture‐recapture method in a vole population
Authors: Tanaka Ryo 
Published: October 2006

SummaryPopulations of the vole,Clethrionomys rufocanus, in a lowland woodlot of Hokkaido were studied for the presence of effects of prebaiting on censusing by the capture‐recapture method. A grid of 121 live‐traps, spaced 5 m apart, was laid out on each of two plots, one of which alone was prebaited three days long. Owing to very high densities and great trap‐efficiency, sufficient and favourable samples could be available for statistical analysis, except the trend of delayed catch for young in sampling. The population on either plot, however, proved to be markedly variable in catchability of unmarked animals in the course of trapping; while the probability of recapture was counted as invariable on the average from day to day, the recapture frequency was different between juveniles, subadults and adults. Needless to say, the catchability was distinctly greater for marked voles than for unmarked ones, whether prebaited or not, through the trapping period, except that the first‐day catchability for unmarked ones on the prebaited plot seems not to be significantly lower than that for marked ones.Consequently, it turns out that the prebaiting has almost never helped to eliminate the important bias induced by differential trap‐response of marked and unmarked animals; its contribution is only that the catchability for unmarked ones is slightly higher on the part of the prebaited plot on earlier days of the period.In accordance with the heterogeneous catchability, the Γ‐form distribution analogous to the geometric could be applied with thorough fitness to the capture frequency in order to estimate the whole populations. The fact that the estimates are reliable, being not at any rate underestimates, was further confirmed by the result of a follow‐up work conducted by means of the removal method with wider trap‐spacing which brought forth distinct underestimation chiefly referable to unexposure to traps of the partial populations. The subject of unexposure was discussed by laying stress on the relation between minimum range length and trap‐spacing.
Ecological assessments of community disorder: Their relationship to fear of crime and theoretical implications
Authors: Perkins Douglas D. , Taylor Ralph B. 
Published: October 2006

AbstractResearchers suggest that fear of crime arises from community disorder, cues in the social and physical environment that are distinct from crime itself. Three ecological methods of measuring community disorder are presented: resident perceptions reported in surveys and on‐site observations by trained raters, both aggregated to the street block level, and content analysis of crime‐ and disorder‐related newspaper articles aggregated to the neighborhood level. Each method demonstrated adequate reliability and roughly equal ability to predict subsequent fear of crime among 412 residents of 50 blocks in 50 neighborhoods in Baltimore, MD. Pearson and partial correlations (controlling for sex, race, age, and victimization) were calculated at multiple levels of analysis: individual, individual deviation from block, and community (block/neighborhood). Hierarchical linear models provided comparable results under more stringent conditions. Results linking different measure of disorder with fear, and individual and aggregated demographics with fear inform theories about fear of crime and extend research on the impact of community social and physical disorder. Implications for ecological assessment of community social and physical environments are discussed.
Family, peer, and neighborhood influences on academic achievement among African‐American adolescents: One‐year prospective effects
Authors: Gonzales Nancy A. , Cauce Ana Mari , Friedman Ruth J. , Mason Craig A. 
Published: October 2006

AbstractUsing a 1‐year prospective design, this study examined the influence of family status variables (family income, parental education, family structure), parenting variables (maternal support and restrictive control), peer support, and neighborhood risk on the school performance of 120 African American junior high school students. In addition to main effects of these variables, neighborhood risk was examined as a moderator of the effects of parenting and peer support. Family status variables were not predictive of adolescent school performance as indexed by self‐reported grade point average. Maternal support at Time 1 was prospectively related to adolescent grades at Time 2. Neighborhood risk was related to lower grades, while peer support predicted better grades in the prospective analyses. Neighborhood risk also moderated the effects of maternal restrictive control and peer support on adolescent grades in prospective analyses. These findings highlight the importance of an ecological approach to the problem of academic underachievement within the African American community.
Statistical analysis of occupancy rates for overdispersed populations by redistribution procedures: Application to the european corn borer EGG masses distribution
Authors: Vaillant J. , Hawlitzky N. 
Published: October 2006

SummaryStandard statistical analyses of distributions of individuals from contingency tables are generally invalid if the individuals are not distributed independently of each other. In this paper, we discuss a method of testing hypotheses about classification category occupancy rates for overdispersed population or for population whose individuals are distributed by groups rather than lonely. These methods are based on population redistribution simulations and provide valid, exact and powerful tests in situations for which classical methods are not appropriate. Illustrations are given from the European Corn Borer eggs data.
Relationships between body size, reproductive traits, and food resource in three species of tropical flesh flies
Authors: Tanaka Seiji , Guardia Modesto , Denlinger David L. , Wolda Henk 
Published: October 2006

SummaryIntra‐ and inter‐specific comparisons in progeny size and clutch size were used to identify possible selection pressures acting on three sympatric species of ovoviviporous flesh flies. Both progeny and clutch sizes increased with body weight of the female parent in all species. There was no evidence for a simple trade‐off between the two traits. In one species, the larger the female adult the smaller the relative biomass of larvae per clutch (total weight of larvae/body weight of female parent). Female flies produced similar progeny and clutch sizes over successive batches. Variation in progeny size did not influence either larval survival or duration of larval and pupal development. However, larger first instar larvae tended to form larger pupae in two of the species. The experiments testing the effect of progeny size on pupal weight under limited food conditions suggest a selective advantage for larger progeny size.
Population dynamics of the green leafhopper, Nephotettix virescens Distant (Hemiptera: Cicadellidae) in synchronized and staggered transplanting areas of paddy fileds in Indonesia
Authors: Widiarta I Nyoman , Suzuki Yoshito , Sawada Hiroichi , Nakasuji Fusao 
Published: October 2006

SummaryThe population dynamics of Nephotettix virescens, a vector of rice tungro virus disease was investigated in a synchronized transplanting area at Jatisari (1984–1986), West Java and in a staggered transplanting area at Sidan (1986–1988), Bali, Indonesia. The FARMCOP suction sampler was employed for population censuses of N. virescens and its natural enemies. The population growth pattern was affected by transplanting pattern: In the staggered transplanting area, the population density increased from the immigrant generation to the first generation, and sharply decrease thereafter, while in the synchronized transplanting area the population density often reached the highest peak in the second generation. The degree of contageousness in the spatial distribution of N. virescens was negatively correlated with population density of the immigrant generation.
Role of a parasitoid with a low fecundity, Praestochrysis shanghaiensis (Hymenoptera: Chrysididae), in the population dynamics of its host
Authors: Yamada Yoshihiro 
Published: October 2006

Summary
Analysis of life tables of the oriental moth, Monema flavescens, obtained for 8 generations over 4 years, disclosed that the cocoon parasitoid, Praestochrysis shanghaiensis, acted as a density‐disruptive factor.
The density of the host cocoon remained stable (max./min.=3.2), whereas that of the host adult varied (max./min.=14.3) although both showed similar fluctation patterns.
Stability of the host population was associated with the density‐dependence in the ratio of first generation cocoons to overwintered generation moths, which was the key factor for the rate of change throughout the year. Chrysidid parasitism among the first generation cocoons ranged from 37.7 to 70.1%, and that among the second generation cocoons from 16.7 to 63.2%, each showing an inverse density‐dependence and acting as the main determinant (key‐factor) of the between‐year variation in the density of the adult moths.
The density‐dependence of the rate of change from overwintered generation adults to first generation cocoons was so strong that the parasitism on the second generation hosts had not effect on the cocoon density of the first generation. On the other hand, the density‐dependence of the rate of change from first generation adults to second generation cocoons was weak, and the parasitism on the first generation hosts became the key factor for the between‐year variation of the second generation cocoons.
It is suggested that the stability of the parasitoid‐host system will be disrupted without three parasitism‐restricting factors: asynchrony in the parasitoid attack on the second generation hosts, high mortality among parasitoid larvae of the second generation, and the high proportion of those first generation parasitoids that enter diapause. These factors are considered to be effective only in cooler parts of the distribution of the parasitoid.
The spatial distribution pattern of the brown planthopper Nilaparvata lugens Stål (Homoptera: Delphacidae) in west Java, Indonesia
Authors: Kusmayadi Ayi , Kuno Eizi , Sawada Hiroichi 
Published: October 2006

SummarySpatial distribution pattern of the brown planthopper (BPH) was analyzed at 9 experimental fields in the northern part of West Java during two consecutive rice cropping seasons, i.e., wet and dry seasons.The population of each developmental stage and wing form of BPH at each location showed consistent departure from the random (Poisson) distribution, the variances of the densities in most cases exceeding their means. Namely, the distribution pattern of BPH per hill of rice plant was found to have a general tendency to be aggregated or contagious and to fit fairly well to the negative binomial model. The tendency for aggregation was further confirmed by both the β‐values of ‐m regression being larger than unity and the CA‐values being larger than zero for each developmental stage.Although significant variations in the distribution pattern as measured by β‐ or CA‐value were observed between different developmental stages, between wing forms and among locations, the degree of aggregation for a given developmental stage at each experimental field remained fairly stable throughout the crop period, despite wide temporal changes in population density.Possible factors to explain these characteristics of the spatial distribution pattern of the BPH in West Java were discussed with reference to the process generating it.
Demography of an island population of the lizard, Eumeces okadae, on Miyake‐jima, Izu Islands
Authors: Hasegawa Masami 
Published: October 2006

SummaryThe demography of the lizard Eumeces okadae was studied for 4 years on Miyake‐jima, in the Izu Islands, central Japan. Most males matured at 3 years of age with a mean snout‐vent length of 77.5 mm. Females matured at 3–4 years with a mean SVL of 77.8 mm, and reproduced biennially thereafter. Growth continued after maturity with a decreasing rate. In females, annual growth was negligible in reproductive years, but resumed markedly in non‐reproductive years. Clutch size increased with SVL and was used to construct a fecundity schedule. Population density (exclusive of hatchlings) was estimated to be ca. 4000 individuals/ha in August, an exceptionally high density for lizards. Before introduction of the weasel onto Miyake‐jima, low predation pressure had allowed E. okadae to maintain a high population density. Estimated annual survival rates were 36% for hatchlings, 56% for yearlings, 80% for 2‐year‐olds, 63% for adult males and 76% for adult females. The cohort generation time (6.95 years) was so long that the E. okadae population can be characterized by a combination of low natality and slow turnover.
Factors influencing development and survival of Culex pipiens pallens larvae (Diptera: Culicidae) in polluted urban creeks
Authors: Mogi M. , Okazawa T. 
Published: October 2006

SummaryFactors influencing development and survival of Culex pipiens pallens immatures in polluted urban creeks were studied in Saga, Japan. Addition of food shortened developmental durations and increased pupal size in floating cages at only the least polluted site out of 4 study sites. There was no evidence for developmental delay due to overcrowding in natural populations. Survival was not increased by artificial feeding at any site. Using the developmental parameters obtained for caged cohorts, survival in natural populations was estimated from differences between the actual number and the expectation if there were no mortality. Pupation rates ranged from 1> to >10% by site and season. Mortality due to predation, evaluated from the difference in pupation rates between caged and natural populations, exceeded 30% in 4 out of 6 cases (twice at 2 sites and once at the other 2 sites). Lethal factors in the creek water caused the predominant mortality in 2 other cases. Regulation of C. pipiens pallens population breeding in eutrophic, open creeks was discussed in the context of larval dispersal through behavioral interference.
The spatial patterns of parasitism of eumenid wasps, Anterhynchium flavomarginatum and Orancistrocerus drewseni by the miltogrammine fly Amobia distorta
Authors: Itino Takao 
Published: October 2006

Summary
Spatial patterns of parasitism of eumenid wasps Anterhynchium flavomarginatum and Orancistrocerus drewseni by the miltogrammine fly Amobia distorta were studied in Kyoto, Japan during 1980–1984.
In generations of low (<5%) and medium (5–20%) parasitism, percent parasitism per shed (the habitat of the hosts) increased as a function of host density. Conversely, in generations of high (>20%) parasitism, percent parasitism was rather constant over different host densities.
The spatial distributions of adult miltogrammine flies among sheds were censused in generations of low and medium parasitism. The frequency of observations of adult miltogrammine flies was higher at sheds of higher host density (aggregative behavioral response), but on the other hand, the adult miltogrammine flies distributed in an underdispersed (or regular) manner in relation to other conspecifics.
The spatially density independent relationship between host density and percent parasitism in generations of high parasitism was explained in relation to parasitoid dispersal from patches of high parasitoid density.