bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assimilation of carbon and nitrogen from pollen and nectar by a predaceous larva and its effects on growth and development
Authors: Patt Joseph M. , Wainright Sam C. , Hamilton George C. , Whittinghill Dexter , Bosley Keith , Dietrick Jan , Lashomb James H. 
Published: December 2003

Abstract.  1. Predaceous insects may benefit from feeding on non‐prey foods, such as pollen, nectar, and honeydew, because they can provide nutrients that help maintain metabolism and enhance overall nutrient intake. Yet, the extent to which predaceous insects can assimilate non‐prey food and the importance of diet mixing during particular life history stages is poorly understood. In this study the relative contribution of an omnivorous diet to the growth and survivorship of a predaceous larva was tested in a hypothetical situation in which nutritionally optimal prey was not available. The study system comprised a predaceous larva (second‐ and third‐instar larvae of the green lacewing Chrysoperla carnea), nutritionally poor prey (larvae of Drosophila melanogaster), and non‐prey food (pollen suspension, a mixture of bee pollen and artificial nectar (1 M sucrose solution)). Chrysoperla carnea larvae in the mixed diet treatment were provided with both Drosophila larvae and pollen suspension, while those reared on the prey and non‐prey diet treatments received only Drosophila larvae or pollen suspension respectively.2. The inclusion of pollen and sucrose in their diet enhanced the growth of C. carnea larvae. Second instars reared on the mixed diet developed significantly faster than their cohorts reared on the prey diet, however third instars reared on the mixed diet did not develop faster than their cohorts reared on the prey diet. Larvae reared on the mixed diet became larger adults than did those reared on either the prey or non‐prey diets. Third instars reared on the non‐prey diet completed their development while second instars in the non‐prey diet treatment failed to pupate.3. Stable isotope analysis indicated that the larvae obtained most of their carbon (55–73%) and nitrogen (71–73%) from Drosophila but acquired only a minor amount of carbon (2–5%) and nitrogen (3–11%) from pollen. Larvae reared on the mixed and non‐prey diets acquired a relatively significant amount of carbon (23–51%) from sucrose.4. A model, which included a novel fractionation factor to account for the isotopic effect of metamorphosis, was developed to explain the proportion of larval growth attributable to each diet item. It explained the adult δ13C values to within 0.2‰ and adult δ15N values to within 0.7‰ in all treatments.5. Adults fed 15N‐labelled pollen as larvae retained the 15N signal of the pollen as adults.6. The collective results of this study support the view that, despite their dependence on prey arthropods to obtain most of their dietary nitrogen, omnivorous lacewing larvae can enhance their growth and development by supplementing their diets with alternative non‐prey food resources. This finding is consistent with the notion that omnivory has evolved as a feeding strategy to acquire both additional nitrogen as well as trace nutrients.
Greater cuticular melanism is not associated with greater immunogenic response in adults of the polymorphic mountain stone weta, Hemideina maori
Authors: Robb T. , Forbes M. R. , Jamieson I. G. 
Published: December 2003

Abstract.  1. Greater immune function is associated with the high‐density melanic phase of polyphenic insects, appearing to compensate for density‐dependent increases in susceptibility to parasites and/or pathogens. Other types of discrete variation in cuticular colour occur in insects (which may or may not be associated with melanin pigmentation), but whether this variation is predictive of immune ability has not been investigated.2. In the mountain stone weta Hemideina maori, a black morph and yellow banded morph occur. These morphs are not seasonally polyphenic and have discrete haplotype genetic markers. Black individuals are typically found at lower local densities than yellow individuals, contrary to relations between cuticular melanism and density seen in polyphenic insects.3. Yellow males and females had greater melanotic encapsulation responses upon immune challenge than did black males and females, but these differences were not associated with differences in temperature selection between morphs. Morph differences in melanotic encapsulation responses were somewhat related to differences between morphs in haemocyte concentrations.4. These results indicate that a common form of immune expression is not heightened with dark coloration in the mountain stone weta. Thus, earlier findings of greater immunity associated with darker cuticles in phase polyphenic insects cannot be extended to insects with other forms of discrete colour variation. These findings will help in elucidating causes and consequences of such colour polymorphism, which is widespread in several insect orders.
Effects of host plant drought stress on the performance of the bird cherry‐oat aphid, Rhopalosiphum padi (L.): a mechanistic analysis
Authors: Hale B. K. , Bale J. S. , Pritchard J. , Masters G. J. , Brown V. K. 
Published: December 2003

Abstract.  1. The growth (increase in height and leaf number) of four grass species was reduced by a −0.5 MPa drought stress, but the performance of an associated herbivore, Rhopalosiphum padi (L.), was not affected consistently. The intrinsic rate of increase of R. padi was reduced by drought stress on three grass species, including Dactylis glomerata (L.), but was unaffected on Arrhenatherum elatius (L.). Therefore, there is no general relationship in the effect of plant drought on an insect herbivore, even among closely related host plant species.2. Drought stress increased the quality of plant phloem sap, as indicated by increased sieve element osmotic pressure and essential amino acid concentrations. Thus, diet quality could not account for the reduced performance of R. padi under drought stress. The concentration of essential amino acids in the phloem of well‐watered A. elatius was, however, lower than that of well‐watered D. glomerata, correlating with the decreased performance of aphids on well‐watered A. elatius.3. There were no differences in aphid feeding duration between watering treatments or plant species but sap ingestion rates were reduced significantly under drought stress.4. Using the measure of dietary amino acid concentrations and the estimate of sap ingestion, the essential amino acid flux through aphids was calculated. Compared with the flux through aphids feeding on well‐watered D. glomerata, there was a reduction in aphids feeding on drought‐stressed D. glomerata and drought‐stressed A. elatius due to lower sap ingestion rates. The flux through aphids on well‐watered A. elatius was also reduced due to low phloem essential amino acid concentrations. Thus, the performance of an aphid is correlated with the availability and accessibility of essential amino acids.
Colony productivity and foundress behaviour of a native wasp versus an invasive social wasp
Authors: Armstrong Tracy R. , Stamp Nancy E. 
Published: December 2003

Abstract.  1. Colony productivity, prey utilisation, and foundress behaviour of a North American native wasp (Polistes fuscatus) versus an European invasive wasp (Polistes dominulus) were investigated in a controlled field experiment with optimal versus natural foraging conditions. Colonies with the optimal prey foraging conditions were provided with prey ad libitum within an enclosed area. The other colonies foraged in the adjacent field–woodland but had the same nest conditions as the other treatment.2. When given prey ad libitum, both wasp species captured similar amounts of prey and the conversion to total offspring biomass was similar. But P. dominulus colonies produced 2.5 times the number of workers as P. fuscatus colonies, reflecting the smaller size of P. dominulus wasps.3. Foundresses of P. dominulus were observed more often building or repairing the nest, thereby contributing to the production of colonies with twice as many cells as colonies of P. fuscatus. Foundresses of P. dominulus showed more acts of aggression toward workers than did P. fuscatus foundresses, which was not a function of adult density on the nest.4. At the end of the experiment, P. dominulus colonies with optimal prey foraging conditions still had a high level of egg‐laying and peaked in the number of pupae then, whereas egg‐laying and the number of pupae per colony of the other treatments began to decline 2–3 weeks earlier. These results indicate that P. dominulus is more opportunistic than P. fuscatus, which may account in part for P. dominulus's success as an introduced species in North America.
Contrasting effects of nitrogen, phosphorus and water regime on first‐ and second‐year growth of 16 wetland plant species
Authors: Güsewell S. , Bollens U. , Ryser P. , Klötzli F. 
Published: December 2003

Summary

The effects of nutrient enrichment on wetland vegetation may depend on the responses of different plant species to nutrient supply over several years, in waterlogged or flooded soils, and under either nitrogen‐ or phosphorus‐limited conditions. However, most growth experiments comparing species from differently productive sites have focused on their short‐term responses to variation in N supply. In this study we investigated whether increased N or P supply affects plant growth differently, whether these effects differ between the first and second year of growth, and whether they are modified by the water regime.
Plants of 16 wetland species were grown during two seasons in tubes with sand under full light. Treatments combined three nutrient levels (low N and P, high N, high P) with three water regimes (constantly wet, periodically aerated, periodically flooded).
In the first year, shoot biomass was enhanced by high N supply, particularly in species from nutrient‐rich sites; this was associated with reduced shoot P concentration. In the second year, shoot biomass was generally enhanced by high P supply and reduced by high N supply; responses to high P were strongest in species with low shoot biomass and high N concentration but unrelated to the productivity of the species’ sites.
The total biomass produced during both years was smaller at high N supply than at high P supply. A smaller fraction of the N and P supply was recovered in high‐N plants, and these plants allocated less biomass to roots than those grown at high P supply or low N and P supply.
Periodic flooding reduced biomass production and nutrient recovery, but hardly influenced the effects of nutrient supply on plant growth. Species from wet meadows were affected more by flooding than species from fens in the first season, but not in the second season.
We propose that high N supply reduced second‐year growth because strong P limitation increased below‐ground nutrient losses from plants, whereas high P supply enhanced second‐year growth by improving N retention in plants. Our results therefore suggest that N and P enrichment may have quite different effects on wetland vegetation.
Copulatory plugs in the Iberian Rock Lizard do not prevent insemination by rival males
Authors: Moreira P. L. , Birkhead T. R. 
Published: December 2003

Summary

Iberian Rock Lizard (Lacerta monticola, Boulenger 1905) males produce copulatory plugs that harden and adhere firmly inside the female cloaca immediately after copulation and occlude both oviductal openings.
To determine whether plugs reduce the chance of females being inseminated by rival males, two hypotheses were tested: (i) that plugs reduce female attractiveness and/or receptivity to rival males; and (ii) that plugs function as ‘chastity belts’.
There was no evidence to support either hypothesis. Neither male initiation of copulations and female termination of male copulation attempts, nor male insemination success differed significantly between trials in which males were presented with females without a plug and with females with a plug deposited by a different male 1, 3 and 6 or more hours earlier, nor between females without and with a plug.
Several hypotheses for the function of Iberian Rock Lizard plugs are discussed. Since rival males were frequently able to displace a plug in the female cloaca, our results are consistent with a ‘sperm protection’ function of male postcopulatory mate guarding in squamate reptiles, but this remains to be tested.
Effects of fire on surface carbon, energy and water vapour fluxes over campo sujo savanna in central Brazil
Authors: Santos A. J. B. , Silva G. T. D. A. , Miranda H. S. , Miranda A. C. , Lloyd J. 
Published: December 2003

Summary

Tower‐based eddy covariance measurements were used to quantify the effect of fire on subsequent carbon dioxide fluxes and water and surface energy balance characteristics for campo sujo savanna located near Brasília in Central Brazil (15°56′ S, 47°51′ W). Campo sujo is a xeromorphic, open shrub savanna with very scattered but definitely visible shrubs and tree‐like shrub elements. We studied two areas, one exposed to a prescribed fire late in the dry season, and a second that had not been burned for the previous 4 years.
The fire on 22 September 1998 consumed an estimated 26 mol C m−2. Immediately after the fire, evapotranspiration rates decreased and the savanna became a stronger net source of CO2 to the atmosphere. This was attributed to the removal of the still slightly physiologically active grass layer and higher soil CO2 efflux rates as a consequence of elevated surface soil temperatures post‐burning.
On the commencement of the first rains in early October 1998, this situation was reversed, with the burned area rapidly becoming a stronger sink for CO2 and with higher evapotranspiration rates than a nearby unburned (control) area. This difference persisted throughout the wet season (until at least June 1999) and was attributable to greater physiological activity of the regrowing vegetation in the burned area. Early in the growing season, higher soil evaporation rates may also have contributed to faster water use by the previously burned area.
Overall, we estimate an annual gross primary productivity for the burned area of 135 mol C m−2 year−1, with that for the unburned area being 106 mol C m−2 year−1. Estimated ecosystem respiration rates were more similar on an annual basis (96 and 82 mol C m−2 year−1 for the burned and unburned areas, respectively), giving rise to a substantially higher net ecosystem productivity for the previously burned area (38 vs 24 mol C m−2 year−1).
Stimulation of photosynthetic activity in the rapid post‐fire growth phase means that the negative effects of fire on the ecosystem carbon balance were more or less neutralized after only 12 months.
Leaf area compounds height‐related hydraulic costs of water transport in Oregon White Oak trees
Authors: Phillips N. , Bond B. J. , McDowell N. G. , Ryan M. G. , Schauer A. 
Published: December 2003

Summary

The ratio of leaf to sapwood area generally decreases with tree size, presumably to moderate hydraulic costs of tree height. This study assessed consequences of tree size and leaf area on water flux in Quercus garryana Dougl. ex. Hook (Oregon White Oak), a species in which leaf to sapwood area ratio increases with tree size. We tested hypotheses that Q. garryana individuals of greater size and leaf area show reduced leaf‐specific hydraulic conductance (KL), crown water flux per leaf area (EL), and carbon isotope discrimination (Δ).
K
L, EL and Δ differed between trees of two size classes examined, with 25 m trees showing evidence of lower water flux and carbon isotopic discrimination compared to 10 m trees. Whole‐tree water fluxes were smaller in 25 m than in 10 m trees both per unit sapwood and per leaf area, but more so per unit leaf area: 25 m trees had a leaf to sapwood area ratio 1·6 times greater than that of 10 m trees.
The findings from this study are unique in that increased leaf to sapwood area ratio of larger trees compounded hydraulic constraints on water transport due to tree height. These results provide further support and generality to the hypothesis of hydraulic limitations to tree‐water flux, and show that limitations to water flux are not necessarily accompanied by the structural compensation of reduced crown leaf area in larger trees.
Fitness consequences of temperature‐mediated egg size plasticity in a butterfly
Authors: Fischer K. , Bot A. N. M. , Brakefield P. M. , Zwaan B. J. 
Published: December 2003

Summary

By randomly dividing adult females of the butterfly Bicyclus anynana, reared in a common environment, among high and low temperatures, it is demonstrated that oviposition temperature induces a plastic response in egg size. Females kept at a lower temperature laid significantly larger eggs than those ovipositing at a higher temperature.
Cross‐transferring the experimentally manipulated eggs between temperatures and investigating hatching success showed that a lower rearing temperature is more detrimental for the smaller eggs produced at a higher temperature than for the larger eggs produced at a lower temperature, supporting an adaptive explanation.
However, when examining two potential mechanisms for an increased fitness of larger offspring (higher desiccation resistance of larger eggs and higher starvation resistance of larger hatchlings), no direct link between egg size and offspring fitness was found. Throughout, i.e. even under benign conditions, larger offspring had a higher fitness.
Therefore, egg size should be viewed as a conveniently measurable proxy for the plastic responses induced by temperature, but caution is needed before implying that egg size per se is causal in influencing offspring traits.
Psychiatric diagnosis in persons with intellectual disability in India
Authors: Kishore M. T. , Nizamie A. , Nizamie S. H. , Jahan M. 
Published: December 2003

AbstractBackground  This study examines the rate of psychiatric diagnosis as per ICD‐10 and Reiss Screen for Maladaptive Behaviours (RSMB), and distribution of psychiatric diagnosis with regard to the severity of intellectual disability (ID). It also explores the degree of agreement between Reiss screen and clinical diagnosis (ICD‐10) in relation to dual diagnosis.Methods  In this study Intelligence (IQ) and Social Quotient (SQ) were estimated on Indian adaptation of Binet's scale and Vineland Social Maturity Scales, respectively, in 60 consecutive persons with ID. Both ICD‐10 and RSMB were used independently to determine the presence of psychiatric diagnosis.Results  Clinically, according to ICD‐10, about 60% of the sample was found to have dual diagnosis as compared to 48% on RSMB. Agreement between ICD‐10 and RSMB about psychiatric comorbidity was 82%. Commonest psychiatric diagnosis was unspecified psychosis followed by bipolar affective disorders.Conclusion  Persons with ID do suffer from various psychiatric disorders. RSMB is a useful tool for differentiating between psychiatric problems and maladaptive behaviours. Hence RSMB can be used in the Indian context.
General psychiatric services for adults with intellectual disability and mental illness
Authors: Chaplin R. 
Published: December 2003

AbstractBackground  Adults with intellectual disability (ID) and mental illness may use general or specialist psychiatric services. This review aims to assess if there is evidence for a difference in outcome between them.Methods  A literature review was conducted using a variety of electronic databases and hand‐search strategies to identify all studies evaluating the outcome of people with ID and mental illness using general psychiatric services.Results  There is no conclusive evidence to favour the use of general or specialist psychiatric services. People with ID stay less time on general psychiatric than specialist inpatient units. People with severe ID appear not to be well served in general services. Older studies of inpatient samples suggest a worse outcome for people with ID. Novel specialist services generally improve upon pre‐existing general services. Assertive outreach in general services may preferentially benefit those with ID. Recent studies suggest similar lengths of stay in general psychiatric beds for people with and without ID.Conclusions  Although 27 studies were located, only two were randomized controlled trials. The evidence is poor quality therefore further evaluation of services employing a variety of designs need to be employed to give more robust evidence as to which services are preferred.
Offenders with intellectual disability: a prospective comparative study
Authors: Barron P. , Hassiotis A. , Banes J. 
Published: December 2003

AbstractBackground  Intellectually disabled offenders (IDO) are a poorly served and under‐recognized group, who are likely to require long‐term specialist treatments and interventions.Method  This prospective study investigated the characteristics and factors that influence outcome in this group, with particular reference to therapeutic interventions. Sixty‐one individuals were identified from contact with either (1) specialist health and social services for people with intellectual disability (ID) or (2) nonspecialist services in the criminal justice or (forensic) mental health/social service systems. The participants were assessed at baseline and after a mean of 10 months in order to compare recidivism rates and the impact of therapeutic interventions.  Results  The findings suggest that IDO start offending at an early age, that they frequently have a history of multiple offences, and that sex offending and arson are over‐represented offence types. Those participants recruited from nonspecialist ID services had significantly higher IQs and were less likely to have had contact with community social and health support agencies. Despite the high rates of psychopathology, there was little evidence for efficacy of therapeutic interventions, which, where offered, appeared to be of a nonspecific nature. At second interview, approximately half of the sample had re‐offended.
Using the Diagnostic Assessment of the Severely Handicapped‐II (DASH‐II) to measure the therapeutic effects of risperidone
Authors: Valdovinos M. G. , Zarcone J. R. , Hellings J. A. , Kim G. , Schroeder S. R. 
Published: December 2003

AbstractBackground  Within the scope of a double‐blind, placebo‐controlled, crossover medication study, the Diagnostic Assessment of the Severely Handicapped‐II (DASH‐II) was evaluated as a measurement for determining the effectiveness of the medication risperidone in treating the problem behaviour of 21 people with intellectual disabilities (ID).Method  Participants’ caregivers completed the DASH‐II during the placebo/baseline phase of the study and the maintenance phase of the study, and completed the Aberrant Behavior Checklist – Community (ABC‐C) weekly throughout the entire study. The results obtained using the DASH‐II were compared to those obtained using the ABC‐C, an instrument shown to be well correlated with the DASH‐II.Results  Results suggest that while the DASH‐II and the ABC‐C were well correlated during the placebo/baseline phase of the current study, they were not well correlated at completion of the 6‐month maintenance phase of the medication trial.Conclusion  The DASH‐II, while appropriate for assisting in the diagnosis of psychopathology in people with ID, does not appear to monitor changes in problem behaviour as a result of risperidone use as well as the ABC‐C. Differences in the frequency of problem behaviour that each measure evaluated and the applicability of using the DASH‐II to measure medication effects on problem behaviour are discussed.