bluuebunny/crossref_metadata_2025_split huggingface dataset:
The estimation of the fitness function from two samples taken from a population
Authors: Manly B. F. J. 
Published: October 2006

SummaryThe fitness of animals subjected to natural selection can be defined as the probability of surviving selection for a given interval of time, or some convenient multiple of this probability. If the fitness of animals is related to some quantitative variable X (such as size) then this relationship is expressed mathematically in the fitness function w(x) and this function can be estimated by comparing the distribution of X in samples taken before and after selection.In this note five methods for estimating the fitness function on the basis of samples from a large population are discussed. They are compared on three previously published sets of data and as a result estimation according to weighted multiple regression is recommended.
Breakup and re‐formation of colony in the first‐instar larvae of the winter cherry bug, Acanthocoris sordidusthunberg (Hemiptera: Coreidae), in relation to the defence against their enemies
Authors: Fujisaki Kenji 
Published: October 2006

SummaryThe winter cherry bug, Acanthocoris sordidusThunberg, lives in aggregation especially in their early larval instars. Using the 1st‐instar larvae of this species, the author tried to clarify both the processes and the mechanisms of the breakup and later re‐formation of colony in relation to the defence against their enemies. The results obtained were summarized as follows.
In the field population, there is a high possibility of dispersal of the 1st‐instar larvae from a colony possibly through the disturbance by some predators but they can re‐form a colony with each other or join, with colonies of different instar larvae.
The individuals in a colony immediately disperse through the attack of predatory coccinellid beetle, Harmonica axyridis but tend to re‐form a colony in a short time.
The breakup of colony is caused by the secretion from the attacked individual.
The formation of colony is attributed to the habit closely related with the senses of smell and/or contact.
From these results, it was concluded that the dispersal of 1st‐instar larvae from a colony, followed by the re‐formation of a colony, is an an adaptive behaviour to escape from the attack by their predators.
Maximum likelihood factor analysis of natural arthropod infestations in stored grain bulks
Authors: Sinha R. N. , Lee P. J. 
Published: October 2006

SummaryInterrelations between natural arthropod fauna and their environment were studied in 1964 from 165 samples collected from the same number of boxcars each containing about 54 tons of stored grain originating from various parts of Western Canada. Applications of several multivariate procedures, such as principal component and maximum likelihood factor analyses (unrotated, rotated and oblique solutions) were applied to 6 biotic and 3 environmental variates to obtain the clearest picture of interrelations among these variates.Jöreskog’s computational procedure and computer programs were used for unrotated, rotated and oblique maximum likelihood solutions. A 3‐factor hypothesis was developed; of the 3 factors the first 2 were significantly correlated (Correlation coefficient=0.78±0.15). The final confirmatory factor analysis revealed that: 1) the first factor indicates that acarine variates, Glycyphagus and Cheyletus, were correlated positively to each other but negatively with the insect Psocoptera, 2) the second factor indicates that the acarine variate Tarsonemus is correlated to moisture, dockage and the entomological variate Psocoptera, 3) the third factor indicates that the environmental factors are correlated to each other, and 4) the correlations between the third factor and the other factors are statistically different from zero.
Analysis of contagiousness in the action of mortality factors on the western tent caterpillar population by using the relationshiprelationship
Authors: Iwao Syun'iti 
Published: October 2006

SummaryThe contagiousness in the operation of mortality processes on the colonies of the western tent caterpillar, Malacosoma californicum pluviale, was analyzed from two different aspects: successive changes in the frequency distribution of the number of surviving individuals per colony in the course of development, and the distribution pattern of the individuals killed by some biotic mortality factors. Also, for a tachinid parasite, Tachinomyia similis, the analysis was made on the egg‐laying pattern on colonies as well as on individual larvae. The methods of these analyses were all based on the relation of mean crowding (m) on mean .A braconid parasite, Rogas sp., tended to kill few individuals together once it attacked a colony, but its effect on host colonies was rather equivalent to the random removal of individuals from all the colonies. Diseases in the late‐stage larvae before cocooning was contagious in their action. Nuclear polyhedrosis virus seemed to have no basic contagiousness in its action, but it caused highly contagious distribution of deaths among the colonies when its average incidence was high. A spore‐forming Bacillus had a tendency to kill several individuals once it appeared in a colony, but the distribution of its incidence (no. of times it appeared per colony) was considered to be nearly at random.The female of Tachinomyia tended to lay more than one egg successively on the same colony. It also attacked individual larvae with a definite tendency for aggregation, which seemed to be resulted from the parasite's preference to large hosts. When the number of eggs laid on prefered hosts exceeded a certain threshold, however, the fly seemed to change its attention to less attractive, smaller individuals.
Environmental factors and sense of community in a planned town
Authors: Plas Jeanne M. , Lewis Susan E. 
Published: October 2006

AbstractPrevious community psychology research has suggested that sense of community can be a powerful explanatory tool for understanding community development and individual well‐being, but has not focused on the relationship of environmental variables to the construct. In other disciplines—especially urban planning—this construct has received more attention but it has not been empirically and systematically studied. The three‐phase qualitative study reported here sampled people representative of those who live and work in Seaside, FL, a town designed to induced sense of community. The data strongly suggest a relationship between a variable set that may define sense of community—membership, need fulfillment, shared emotional connections, loyalty—and the environmental variables of town design, architecture, and urban planning philosophy.
Understanding environments: The key to improving social processes and program outcomes
Authors: Moos Rudolf H. 
Published: October 2006

AbstractThe contributions to this Special Issue illustrate research on several important types of environmental units, including psychiatric and substance abuse treatment programs, neighborhood block groups, and entire communities. They also exemplify alternative methodologies, such as assessing environments by relying on participants' appraisals, external observers' ratings, historical archives, and direct observation. I draw on these contributions and some of my own work to discuss four recurrent issues: (a) how to conceptualize environmental domains and dimensions; (b) how to understand environmental dynamics, that is, the interplay of environmental factors both within one setting and across settings; (c) how to comprehend the processes that link environmental factors to outcomes, especially with respect to the power and evanescence of environmental influence; and (d) how to use information about environments to monitor and improve them. Increased knowledge in these four areas is essential to help fulfill a major aim of community psychology: to understand social processes and improve intervention program outcomes.
A multidimensional measure of neighboring
Authors: Skjæveland Oddvar , Gärling Tommy , Mæland John Gunnar 
Published: October 2006

AbstractThe study reports the development of a short and easily administered questionnaire aiming at measuring dimensions of social life within neighborhoods. Principal‐components analysis consistently extracted four factors replicated in three independent samples (N=96 to 1,060). The factors emerged as theoretically meaningful dimensions tapping the concepts of supportive acts of neighboring, neighbor annoyance, neighborhood attachment, and weak social ties. Factor invariance and factor replicability were high. Internal consistency, test‐retest reliability, and construct validity yielded acceptable results. The principal virtue of the measure is that it may be applied to discern qualitative differences between neighborhoods by simultaneous assessments of several dimensions of neighboring.
The population dynamics of the large pine aphid, Cinara pinea (Mordv.)
Authors: Kidd N. A. C. 
Published: October 2006

SummaryThe paper describes the development of a computer model designed to simulate the field population dynamics of the large pine aphid, Cinara pinea. Emphasis was placed on the analysis of intrinsic factors influencing population changes and no attempt was made to include natural enemy functions at this stage. The model was able to account for 52% of the numerical variation within and between experimentally controlled populations on saplings in the field. Agreement between the model's predictions and population dynamics on mature field trees was also good, particularly during the early part of the season. Only after the midsummer peak do significant discrepancies emerge, the difference reflecting the likely impact of natural enemies, which became abundant at this time.Intrinsic density‐dependent processes, while shown to occur in Cinara pinea, were found to be of little significance in determining population numbers in the field. In practice, it is seasonal and between‐tree variations in plant quality that appear to be of major importance in determining population densities in the field. Predators, too, by influencing numbers later in the season are likely to affect the number of overwintering eggs laid and hence the peak number the following year. However, even in the absence of predation, tree quality effects are capable of restricting aphid numbers to within field‐observed limits over a period of years.
Predation of Cyrtorhinus lividipennis Reuter on eggs of the green leafhopper and brown planthopper in rice
Authors: Heong K. L. , Bleih Saad , Lazaro Amor A. 
Published: October 2006

SummaryThe functional response of Cyrtorhinus lividipennis feeding on brown planthopper (BPH) and green leafhopper (GLH) eggs was found to be Holling's Type II. The Random Predator Equation fitted the data satisfactorily. Using Manly's preference index, α, both the male and female C. lividipennis were found to prefer BPH eggs. There was, however, no evidence of switching and the ratio of the respective searching efficiencies could account for the preference.
‘Harem’ and ‘non‐harem’ type mating systems in two species of subsocial spider mites (Acari, Tetranychidae)
Authors: Saitō Yutaka 
Published: October 2006

SummaryThe mating system of a subsocial spider mite, Schizotetranychus miscanthi Saitō, which is closely related to Schizotetranychus longus Saitō (the long seta form of Schizotetranychus celarius (Banks) is a synonym of the latter) was studied in comparison with that of S. longus.Comparisons between nesting patterns of the two related species, S. miscanthi and S. longus revealed a difference in distribution of males among nests. Although more than one male sometimes occurred in the large nests of S. miscanthi, most nests were occupied only by a single male. On the other hand, many nests of S. longus included several males.Behavioral experiments revealed that the male and females of S. miscanthi which cohabited in a nest defended their offspring from phytoseiid predators. Observations and a census of the nesting pattern in a wild population indicate that this is the second example of biparental defense and of a subsocial life‐pattern in spider mites.Differences in mating systems were experimentally demonstrated in the two species. Only a single male of S. miscanthi survived in a nest, as a result of highly aggressive male‐male combat, while two males of S. longus cohabited in a nest. The mating system of the former species is thus considered as harem polygyny, while that of the latter as scramble type polygyny. Furthermore, observations by video recording and scanning electron microscopy showed that the winning male in the male‐male combat in S. miscanthi often preyed on the loser, suggesting cannibalism among them.
Genetic analysis of the wing‐form determination of the small brown planthopper, Laodelphax striatellus (Hemiptera: Delphacidae)
Authors: Mori Kiyoko , Nakasuji Fusao 
Published: October 2006

SummaryThe mechanism of the genetic control of wing form determination of the small brown planthopper Laodelphax striatellus was analyzed by selection and crossing experiments. The selection experiment for brachypterous and macropterous forms for 13 generations showed that the wing form is under some genetic control. The crossing experiment showed that the wing form polymorphism was not a simple Mendelian character but was under polygenic control. The data from the crossing experiment were applied to the liability method for the quantitative genetics by Falconer (1981). The analysis suggested that wing form determination was a threshold character under polygenic control, and the estimated minimum number of loci concerned was 2.07. The realized heritability estimated from the data of selection experiment was 0.36 for macroptery. On the other hand, the heritability in broad sense estimated on the basis of the variance of F1 and F2 in crossing experiment was 0.81.
Effect of population density on reproduction of two sympatric dung beetle species, Aphodius haroldianus and A. Elegans (Coleoptera: Scarabaeidae)
Authors: Yasuda Hironori 
Published: October 2006

SummaryThe effect of population density on reproduction as well as the oviposition modes of two sympatric dung beetle species, Aphodius haroldianus (a low fecundity/high parental effort species) and A. elegans (a high fecundity/low parental effort species) was studied at a pasture in central Japan from 1982 to 1986.
The adult population density of A. haroldianus was high (>40 per dung pat). The density of A. elegans was low (<5 per dung pat). Oviposition of A. haroldianus was suppressed above the density of about 10 adults of conspecifics but not affected by the density of other species. The intra‐ and interspecific density effects on oviposition were not detected in A. elegans.
The number of A. haroldianus adults per pat decreased with dung age, while that of A. elegans increased until sixth day after deposition and then decreased. The number of eggs laid per pat was not different between 1‐day‐and 3‐day‐old pats for A. haroldianus. However, more eggs of A. elegans were found in 3‐day‐old pats than in 1‐day‐old ones.
In the both species, the amplitude of population fluctuations was not remarkable; the maximum/minimum ratio for five years being 2.3 for A. haroldianus and 2.9 for A. elegans. Different density dependent processes were suggested to function for the small fluctuation of population density between the two species, i.e. intraspecific density effect on oviposition for A. haroldianus and contest type competition for food among larvae of A. elegans.
Population dynamics of Luehdorfia japonica Leech (Lepidoptera: Papilionidae)
Authors: Matsumoto Kazuma 
Published: October 2006

SummaryMortality processes from egg to final instar larval stage are examined in the papilionid butterfly Luehdorfia japonica for two generations in a natural populations. Special attention is given to the effects of initial egg cluster size on the survival rate by the 3rd instar. Mean egg cluster sizes for the two generations were 11.3 and 10.7. The hatching rate was not affected by the egg cluster size. Up to 3rd instar, larvae in a group were more likely to die en masse rather than to die individually, whereas most larvae in later instars died independently. The egg clusters of the average (and the most frequent) size class (11±1) had the second highest survival rate until the 3rd instar. A slightly higher survival rate occurred in clusters a little larger (14±1). The average size clusters were least likely to be exterminated and about 70% of them produced at least one individual surviving to the 3rd instar. Factors affecting the observed mortality patterns were discussed.
Univoltine and bivoltine life cycles in insects: A model with density‐dependent selection
Authors: Sota Teiji 
Published: October 2006

SummarySelection for univoltine and bivoltine life cycles in insects under resource‐limited but favourable temperature conditions is analyzed with a difference equation model including density‐dependent population dynamics based on the conceptual framework of an evolutionarily stable strategy. The model predicts that the bivoltine type can spread in a univoltine population when the fraction of density‐independent rate of annual increase by producing a second generation exceeds the survival rate during diapause of the univoltine type, but monopoly of the bivoltine type is not possible unless it attains an equilibrium population density exceeding that of the univoltine type. The applicability of the model prediction in explaining the occurrence of a partial bivoltine cycle in predominantly univoltine population in the temperate zones is discussed.
Seasonality parameters for insect populations
Authors: Wolda Henk 
Published: October 2006

SummaryThe usefulness of a number of parameters is investigated for describing the seasonal variability in insect populations, especially in relation to sample size.It is found that Seasonal Niche Breadth (B) and its maximal value (BM) are useful only for large samples. For smaller samples one tends to find the same values for these parameters whatever the distribution they are supposed to describe. The “standardized” ratio of these two parameters (B/BM) is completely useless.The Season Length (S. L.), defined as 52 minus the longest series of weeks in which the species was absent, or not observed, was found to be quite useful, especially at smaller sample sizes. For species which occur over a large part of the year and have been observed in large numbers, the ratio Min/Max is found to be quite useful. This is the number of individuals during the four weeks at the low point of the season divided by the number observed during the four weeks in the peak of the season.It is suggested that the seasonal distribution be estimated using S. L. or, when appropriate, Min/Max in order to estimate the Seasonal Standard Deviation (SSD), which assumes a normal seasonal distribution. With this SSD the 99 per cent range (Seasonal Range) can be calculated to characterize the seasonal distribution.With this Seasonal Range different species or different areas can profitably be compared in their seasonality characteristics even if there is a large difference in sample size.
Anopheles subpictusGrassi: Observations on survivorship and population size using mark‐release‐recapture and dissection methods
Authors: Reisen William K. , Mahmood Farida , Parveen Tauheeda 
Published: October 2006

SummaryA mark‐release‐recapture experiment to estimate population survivorship and absolute size was performed with wild‐caughtAn. subpictusadults at the village of Khano‐Harni, Lahore District, Punjab Province, Pakistan during September 1978, the end of the monsoon rainy season, when temporal population abundance was maximized. Daily survival rate estimated from the recapture sequence of marked adults was low, males=0.192 and females=0.343. Survivorship for females estimated by several vertical age‐grading procedures ranged from 0.347 to 0.628. Both stage‐ and age‐specific life tables were calculated from vertical age‐grading data determined by the dilatation method. Female and male population size was estimated byBailey's modification of theLincolnIndex and was found to average 4478.4 and 6106.8, respectively. The bionomics, survivorship and population size ofAn. subpictusin the Lahore are indicated that this species was probably not important in the transmission of human malaria.
The estimation and simulation of variable developmental period, with application to the mosquito Aedes aegypti (L.)
Authors: Birley Martin H. 
Published: October 2006

SummaryThe variability of stage developmental period may be a seminal feature of some insect populations and therefore of importance in management studies. A transfer function technique is described for estimating the frequency distribution of developmental period and simulating the subsequent population dynamics. The technique relates recruitment time series of consecutive stages by an age‐specific developmental success function. Approximate statistics, such as the mean, median or mode developmental period, may be determined and the effect of different temperature or density regimes compared.
Estimation of stage‐specific developmental times and survivorship from stage frequency data
Authors: Schneider S. M. , Ferris H. 
Published: October 2006

SummaryAn algorithm for estimating mean stage durations, the standard deviations associated with the means, and stage‐specific survivorships from stage frequency data is presented. The algorithm is based on an age‐structured, distributed delay simulation model which usesErlang distributions to determine the probability of maturity for individuals in each stage. If the data set extends beyond the first generation, the algorithm requires a fecundity rate, as well as stage frequencies, as input. Goodness‐of‐fit was measured using a weighted least squares calculation summed over all observed stages and all sampling dates.
A high prevalence of sleep disordered breathing in men with mild symptomatic chronic heart failure due to left ventricular systolic dysfunction
Authors: Vazir A. , Hastings P.C. , Dayer M. , McIntyre H.F. , Henein M.Y. , Poole‐Wilson P.A. , Cowie M.R. , Morrell M.J. , Simonds A.K. 
Published: October 2006

AbstractBackground:Sleep disordered breathing (SDB) is common in severe chronic heart failure (CHF) and is associated with increased morbidity and mortality. The prevalence of SDB in mild symptomatic CHF is unknown.Aim:The aim of this study was to determine the prevalence and characteristics of SDB in male patients with NYHA class II symptoms of CHF.Methods and results:55 male patients with mild symptomatic CHF underwent assessment of quality of life, echocardiography, cardiopulmonary exercise, chemoreflex testing and polysomnography. 53% of the patients had SDB. 38% had central sleep apnoea (CSA) and 15% had obstructive sleep apnoea. SDB patients had steeper VE/VCO2 slope [median (inter‐quartile range) 31.1 (28–37) vs. 28.1 (27–30) respectively; p=0.04], enhanced chemoreflexes to carbon dioxide during wakefulness [mean±sd: 2.4±1.6 vs. 1.5±0.7%VE Max/mmHg CO2 respectively; p=0.03], and significantly higher levels of brain natriuretic peptide and endothelin‐1 compared to patients without SDB. No differences in left ventricular ejection fraction, percent predicted peak oxygen uptake, or symptoms of SDB were observed.Conclusions:A high prevalence of SDB was found in men with mild symptomatic CHF. Patients with SDB could not be differentiated by symptoms or by routine cardiac assessment making clinical diagnosis of SDB in CHF difficult.