bluuebunny/crossref_metadata_2025 huggingface dataset:
Reproduction, growth and maturity in the black flying-fox, Pteropus alecto (Megachiroptera : Pteropodidae)
Authors: Vardon M. J. , Tidemann C. R.
Published: August 2004

This paper reviews the timing of reproduction, growth rates and age at
maturity of the black flying-fox, Pteropus alecto. This
species is found from Sulawesi, Indonesia, south to the central east coast of
Australia. In northern Australia at 12ºS most young are born in
January–March, in contrast to October–November at 27ºS in
eastern Australia, but a small percentage of young are born outside the major
birth peaks in both areas. The birth peaks of P. alecto
appear to be aligned with periods of maximum plant productivity, rather than
day length. The plasticity of breeding season is likely to be an important
factor enabling P. alecto to colonise areas from near
the equator to 29ºS.
Individual growth rates were calculated for 27
P. alecto. The weight growth rate of these animals was
2.40 3.14 g day-1 (mean s.d.), while growth rate of the
forearm was 0.19 0.18 mm day-1 (mean s.d.). The growth
rate of the forearm of females was significantly greater than for males
(P = 0.08). From the mean forearm lengths of
animals trapped, separate growth curves were developed for juvenile males
(n = 566) and females (n
= 610); these indicate that growth rate of females is about 8%
higher than that of males. Primiparous females had a forearm length of 171.1
3.4 mm (mean s.d.) (n = 5), which is achieved
15–17 months after birth, but about a third of females with forearm
lengths of 160–170 mm have suckled young. Males mature at an age greater
than females due to their slower growth rate, a phenomenon known from other
megachiropteran species.
The temporal character of feeding behaviour in captive tammar wallabies (Macropus eugenii Desmarest)
Authors: Lentle R. G. , Stafford K. J. , Potter M. A. , Springett B. P. , Haslett S.
Published: August 2004

Four tammar wallabies, maintained in a fixed 12 : 12 light : dark cycle, were
fed ad libitum, one of three foods, of differing
nutrient density and fibre content, consecutively, each for a period of two
weeks. During the second week, food consumption was assessed daily and the
temporal feeding pattern was monitored by visible and infrared video
recording. Apart from a short rest period around noon, feeding continued
throughout the 24-hour cycle, peaking crepuscularly. Total daily feeding time
corrected to metabolic body weight was significantly longer, but dry-matter
intake corrected to metabolic body weight was significantly lower than that of
larger macropod species, indicating greater investment in chewing. Feed-event
duration, inter-feed-event interval, rate of feeding, and dry matter intake
all increased significantly on pelleted foods of low nutritional density. Rate
of feeding and feed-event duration increased significantly on diced carrot
such that dry-matter intake was not significantly different to that on
high-quality pelleted food. Survivorship curves of inter-feed-event intervals
were predominantly linear. This and the consistently higher positive
correlations between the duration of individual feed events and
inter-feed-event intervals than between meals and inter-meal intervals,
indicated a nibbling rather than a meal-based feeding strategy. Levels of
correlation of feed-event duration with inter-feed-event interval were
generally low but there was a significant increase in positive correlation
when food of lower quality was given. The duration of successive feed events
tended to increase on low-quality and decrease on high-quality food more
consistently than did successive inter-feed-event intervals.
Characteristics of protonephridial terminal organs and the eyes of four species of Trigonostominae (Platyhelminthes : Rhabdocoela)
Authors: Watson Nikki A.
Published: August 2004

Two complex, phylogenetically informative structures were investigated using
transmission electron microscopy in four species within a small taxonomic unit
of rhabdocoel turbellarians. A synapomorphic modification of the structure of
the protonephridial terminal organs, viz. reduced
definition of the filtration ribs, was found in three of the species,
Ceratopera sp.,
Proxenetes fasciger and
Trigonostomum setigerum. Modifications of the
mitochondrial lensing elements found in the eyes of
Beklemischeviella contorta implied that it may join with
Ptychopera westbladi to form a branch within the
subfamily, while the distribution of lensing from giant mitochondria
illustrated the plasticity of this feature. The study demonstrates the
potential of such characters to assist phylogenetic resolution, but highlights
the danger of using the characteristics of single species to represent larger
taxa.
Use of stream and river habitats by the platypus, Ornithorhynchus anatinus, in an urban fringe environment
Authors: Serena M. , Thomas J. L. , Williams G. A. , Officer R. C. E.
Published: August 2004

Radio-telemetry was used to monitor movements and burrow usage by
O. anatinus living in the Yarra River catchment, about
20 km east-north-east of the central business district of Melbourne, Victoria.
The home ranges of six adult or subadult animals were 2.9–7.3 km (mean
± s.d. = 4.6 ± 1.6 km) long, with individuals travelling
up to 10.4 km (males) and 4.0 km (females) in a single overnight period. The
mean home-range length of adult/subadult animals was significantly greater
than that of juveniles (1.4–1.7 km, mean ± s.d. = 1.55
± 0.2 km, n = 2). The animals utilised two
drainage channels as well as 11.8 km of natural waterways, including the Yarra
River (5 km), Mullum Mullum Creek (4 km) and Diamond Creek (2.8 km). Several
animals travelled repeatedly below one-lane and two-lane bridges, confirming
that these structures are not inherent barriers to platypus movement. In
total, 57 platypus burrows were described, including 26 along the river, 29
along the creeks and 2 along drains. The horizontal distance from the
water’s edge to burrow chambers was 0.4–3.7 m (mean ± s.d.
= 1.5 ± 0.9 m, n = 41), with
burrows found only in banks extending ≥ 0.5 m above the water. Platypus
burrows occurred significantly more often than expected along undercut banks
and in association with moderate-to-dense vegetation overhanging the water,
and significantly less often at sites where banks had a convex profile at
water level. As well, the amount of cover provided along the bank by
shrubs/small trees and the ground layer of vegetation was significantly
greater than expected at platypus burrows along the river. These attributes
are believed to help conceal burrow entrances from predators as well as reduce
burrow damage through erosion.
Efficient system-wide coordination in noisy environments
Authors: Moreira André A. , Mathur Abhishek , Diermeier Daniel , Amaral Luís A. N.
Published: August 2004

Many natural and social systems display global organization and coordination without centralized control. The origin of this global coordination is a topic of great current interest. Here we investigate a density-classification task as a model system for coordination and information processing in decentralized systems. We show that sophisticated strategies, selected under idealized conditions, are not robust to environmental changes. We also demonstrate that a simple heuristic is able to successfully complete the classification task under a broad range of environmental conditions. Our findings hint at the possibility that complex networks and ecologically efficient rules coevolve over time.
A detailed picture of the origin of the Australian dingo, obtained from the study of mitochondrial DNA
Authors: Savolainen Peter , Leitner Thomas , Wilton Alan N. , Matisoo-Smith Elizabeth , Lundeberg Joakim
Published: August 2004

To determine the origin and time of arrival to Australia of the dingo, 582 bp of the mtDNA control region were analyzed in 211 Australian dingoes sampled in all states of Australia, 676 dogs from all continents, and 38 Eurasian wolves, and 263 bp were analyzed in 19 pre-European archaeological dog samples from Polynesia. We found that all mtDNA sequences among dingoes were either identical to or differing by a single substitution from a single mtDNA type, A29. This mtDNA type, which was present in >50% of the dingoes, was found also among domestic dogs, but only in dogs from East Asia and Arctic America, whereas 18 of the 19 other types were unique to dingoes. The mean genetic distance to A29 among the dingo mtDNA sequences indicates an origin ≈5,000 years ago. From these results a detailed scenario of the origin and history of the dingo can be derived: dingoes have an origin from domesticated dogs coming from East Asia, possibly in connection with the Austronesian expansion into Island Southeast Asia. They were introduced from a small population of dogs, possibly at a single occasion, and have since lived isolated from other dog populations.
A mechanical basis for chromosome function
Authors: Kleckner Nancy , Zickler Denise , Jones Gareth H. , Dekker Job , Padmore Ruth , Henle Jim , Hutchinson John
Published: August 2004

We propose that chromosome function is governed by internal mechanical forces generated by programmed tendencies for expansion of the DNA/chromatin fiber against constraining features.
Highly efficient gene replacements in
Neurospora
strains deficient for nonhomologous end-joining
Authors: Ninomiya Yuuko , Suzuki Keiichiro , Ishii Chizu , Inoue Hirokazu
Published: August 2004

Gene disruption and overexpression play central roles in the analysis of gene function. Homologous recombination is, in principle, the most efficient method of disrupting, modifying, or replacing a target gene. Although homologous integration of exogenous DNA into the genome occurs readily in
Saccharomyces cerevisiae
, it is rare in many other organisms. We identified and disrupted
Neurospora crassa
genes homologous to human
KU70
and
KU80
, which encode proteins that function in nonhomologous end-joining of double-stranded DNA breaks. The resulting mutants, named
mus
-
51
and
mus
-
52
, showed higher sensitivity to methyl methanesulfonate, ethyl methanesulfonate, and bleomycin than wild type, but not to UV, 4-nitroquinoline 1-oxide, camptothecin, or hydroxyurea. Vegetative growth, conidiation, and ascospore production in homozygous crosses were normal. The frequency of integration of exogenous DNA into homologous sequences of the genome in the
KU
disruption strains of
N. crassa
was compared with that in wild type,
mei-3
, and
mus
-
11
. In
mei-3
and
mus
-
11
, which are defective in homologous recombination, none or few homologous integration events were observed under any conditions. When
mtr
target DNA with ≈2-kb 5′ and 3′ flanking regions was used for transformation of the
KU
disruption strains, 100% of transformants exhibited integration at the homologous site, compared to 10 to 30% for a wild-type recipient. Similar results were obtained when the
ad-3A
gene was targeted for disruption. These results indicate that
KU
disruption strains are efficient recipients for gene targeting.
CisModule:
De novo
discovery of cis-regulatory modules by hierarchical mixture modeling
Authors: Zhou Qing , Wong Wing H.
Published: August 2004

The regulatory information for a eukaryotic gene is encoded in cis-regulatory modules. The binding sites for a set of interacting transcription factors have the tendency to colocalize to the same modules. Current
de novo
motif discovery methods do not take advantage of this knowledge. We propose a hierarchical mixture approach to model the cis-regulatory module structure. Based on the model, a new
de novo
motif-module discovery algorithm, CisModule, is developed for the Bayesian inference of module locations and within-module motif sites. Dynamic programming-like recursions are developed to reduce the computational complexity from exponential to linear in sequence length. By using both simulated and real data sets, we demonstrate that CisModule is not only accurate in predicting modules but also more sensitive in detecting motif patterns and binding sites than standard motif discovery methods are.
Quasiclassical computation
Authors: Remacle F. , Levine R. D.
Published: August 2004

The chemical kinetic description of time evolution where the phase is random but the states are discrete is discussed as a basis for a computational approach. This proposed scheme uses numbers in the entire range of 0 to 1 to represent Boolean propositions. In the implementation by chemical kinetics these numbers are the mole fractions of different species. Vibrational relaxation in a mixture of HCl and DCI is the physical system that is used to illustrate the approach. Energy exchange in such a mixture corresponds to two strongly coupled two-level systems. A search problem, previously discussed in the quantum computing literature, is solved as an example. The solution requires the same number of function evaluations as in the quantal case. The action of the oracle is described in detail.
Total synthesis of (±)-halichlorine, (±)-pinnaic acid, and (±)-tauropinnaic acid
Authors: Christie Hamish S. , Heathcock Clayton H.
Published: August 2004

The related marine natural products halichlorine, pinnaic acid, and tauropinnaic acid have been synthesized. The described route provided access to all three compounds from a common, late-stage intermediate. The synthesis began with 1-pyrrolidino-1-cyclopentene from which an intermediate possessing the three contiguous stereocenters of the natural products was synthesized in just four steps. Olefin cross metathesis followed by a hydrogenation/hydrogenolysis reaction stereoselectively formed the piperidine ring. Use of a β-lactam group provided internal protection for the highly congested nitrogen atom during side-chain elaboration. The β-lactam was subsequently reduced directly to an amino aldehyde, which after the Horner–Wadsworth–Emmons reaction was elaborated to pinnaic acid. The same amino aldehyde was also transformed into halichlorine after a thiol-mediated cyclization sequence to form the dehydroquinolizidine ring system.
K
+
channel interactions detected by a genetic system optimized for systematic studies of membrane protein interactions
Authors: Obrdlik Petr , El-Bakkoury Mohamed , Hamacher Tanja , Cappellaro Corinna , Vilarino Cristina , Fleischer Carola , Ellerbrok Heinz , Kamuzinzi Richard , Ledent Valérie , Blaudez Damien , Sanders Dale , Revuelta Jose L. , Boles Eckhard , André Bruno , Frommer Wolf B.
Published: August 2004

Organization of proteins into complexes is crucial for many cellular functions. However, most proteomic approaches primarily detect protein interactions for soluble proteins but are less suitable for membrane-associated complexes. Here we describe a mating-based split ubiquitin system (mbSUS) for systematic identification of interactions between membrane proteins as well as between membrane and soluble proteins. mbSUS allows
in vivo
cloning of PCR products into a vector set, detection of interactions via mating, regulated expression of baits, and improved selection of interacting proteins. Cloning is simplified by introduction of λ attachment sites for GATEWAY. Homo- and heteromeric interactions between
Arabidopsis
K
+
channels KAT1, AKT1, and AKT2 were identified. Tests with deletion mutants demonstrate that the C terminus of KAT1 and AKT1 is necessary for physical assembly of complexes. Screening of a sorted collection of 84 plant proteins with K
+
channels as bait revealed differences in oligomerization between KAT1, AKT1, and AtKC1, and allowed detection of putative interacting partners of KAT1 and AtKC1. These results show that mbSUS is suited for systematic analysis of membrane protein interactions.
Highly pathogenic SHIVs and SIVs target different CD4+T cell subsets in rhesus monkeys, explaining their divergent clinical courses
Authors: Nishimura Yoshiaki , Igarashi Tatsuhiko , Donau Olivia K. , Buckler-White Alicia , Buckler Charles , Lafont Bernard A. P. , Goeken Robert M. , Goldstein Simoy , Hirsch Vanessa M. , Martin Malcolm A.
Published: August 2004

In contrast to simian immunodeficiency viruses (SIVs), which induce immunodeficiency over a 1- to 3-year period, highly pathogenic simian-human immunodeficiency viruses (SHIVs) cause a complete, irreversible, and systemic depletion of CD4+T lymphocytes in rhesus monkeys within weeks of infection. By using small-molecule competitors specific for CCR5 and CXCR4 inex vivoassays, we found that highly pathogenic SHIVDH12Rexclusively uses CXCR4 for infection of rhesus peripheral blood mononuclear cells, whereas SIVmac239and SIVsmE543use CCR5 for entry into the same cells. During the period of peak virus production in SHIVDH12R- or SHIV89.6P-infected rhesus monkeys, massive elimination of CXCR4+naïve CD4+T cells occurred. In contrast, circulating CCR5+memory CD4+T cells were selectively depleted in rapidly progressing SIV-infected monkeys. At the time of their death, two SIV rapid progressors had experienced a nearly complete loss of the memory CD4+T cell subset from the blood and mesenteric lymph nodes. Thus, pathogenic SHIVs and SIVs target different subsets of CD4+T cellsin vivo, with the pattern of CD4+T lymphocyte depletion being inextricably linked to chemokine receptor use. In the context of developing an effective prophylactic vaccine, which must potently control virus replication during the primary infection, regimens that suppress SHIVs might not protect monkeys against SIV or humans against HIV-1.
Essential role for virus-neutralizing antibodies in sterilizing immunity against Friend retrovirus infection
Authors: Messer Ronald J. , Dittmer Ulf , Peterson Karin E. , Hasenkrug Kim J.
Published: August 2004

The current experiments use the Friend retrovirus model to demonstrate that vaccine-primed B cells are essential for sterilizing immunity, and the results indicate that the requisite function of these cells is the production of virus-neutralizing antibodies rather than priming or reactivation of T cells. B cell-deficient mice were poorly protected by vaccination, but adoptive transfer experiments showed that the T cells from B cell-deficient mice were primed as well as those from wild-type mice. Furthermore, passive transfer of virus-neutralizing antibodies completely compensated for B cell deficiency. The presence of virus-neutralizing antibodies at the time of infection was crucial for vaccine efficacy. Interestingly, virus-neutralizing antibodies worked synergistically with vaccine-primed T cells to provide a level of protection many orders of magnitude greater than either antibodies or immune T cells alone. Nonneutralizing antibodies also contributed to protection and acted cooperatively with neutralizing antibodies to reduce infection levels. These results emphasize the importance of inducing both T cell responses and virus-neutralizing antibody responses for effective retroviral vaccine protection.
Therapeutic cancer vaccines: Using unique antigens
Authors: Lewis Jonathan J.
Published: August 2004

A decade ago, it seemed rational that our rapidly increasing knowledge of the molecular identities of tumor antigens and a deeper understanding of basic immunology would point the way to an effective therapeutic cancer vaccine. Significant progress has been made, but we do not yet have a cancer vaccine that can reliably and consistently induce tumor destruction or improve patient survival. Random mutations in cancer cells generate unique antigens in each individual, and this may be important in terms of generating a therapeutic immune response. Autologous heat shock protein–peptide complexes produced from each patient's tumor is a logical personalized approach that may obviate the need to identify the unique antigens contained in the individual vaccine. Heat shock proteins elicit adaptive and innate immune responses and have been tested in a variety of animal models and different human cancers. Activity has been seen in several animal studies. Early-phase human studies have also suggested some activity in certain cancers. Large, randomized phase 3 studies are ongoing, and these will effectively answer the question of efficacy regarding this approach to therapeutic vaccination. There are sufficient data to support the notion that cancer vaccines can induce anti-tumor immune responses in humans with cancer. How best to translate this increase in immune responsiveness to consistently and reproducibly induce objective cancer regression or increased survival remains unclear at this time.
Structure of the photolyase-like domain of cryptochrome 1 from
Arabidopsis thaliana
Authors: Brautigam Chad A. , Smith Barbara S. , Ma Zhiquan , Palnitkar Maya , Tomchick Diana R. , Machius Mischa , Deisenhofer Johann
Published: August 2004

Signals generated by cryptochrome (CRY) blue-light photoreceptors are responsible for a variety of developmental and circadian responses in plants. The CRYs are also identified as circadian blue-light photoreceptors in
Drosophila
and components of the mammalian circadian clock. These flavoproteins all have an N-terminal domain that is similar to photolyase, and most have an additional C-terminal domain of variable length. We present here the crystal structure of the photolyase-like domain of CRY-1 from
Arabidopsis thaliana
. The structure reveals a fold that is very similar to photolyase, with a single molecule of FAD noncovalently bound to the protein. The surface features of the protein and the dissimilarity of a surface cavity to that of photolyase account for its lack of DNA-repair activity. Previous
in vitro
experiments established that the photolyase-like domain of CRY-1 can bind Mg·ATP, and we observe a single molecule of an ATP analog bound in the aforementioned surface cavity, near the bound FAD cofactor. The structure has implications for the signaling mechanism of CRY blue-light photoreceptors.
Immunotherapy for Alzheimer's disease
Authors: Gelinas David S. , DaSilva Kevin , Fenili Daniela , St. George-Hyslop Peter , McLaurin JoAnne
Published: August 2004

The utility of vaccine strategies to treat neurodegenerative diseases such as Alzheimer's disease (AD) may still hold promise. Both active and passive immunization strategies reduced AD-like pathology and restored cognitive deficits in transgenic mice. These results were initially met with considerable optimism; however, phase IIa clinical trials were halted because of a small but significant occurrence of meningoencephalitis. Knowledge gained from studies on amyloid-β peptide (Aβ) immunotherapy will allow optimization of new-generation vaccines, targeting highly specific epitopes while reducing undesired side effects. In harnessing and steering the immune system, an effective response can be generated against Aβ. If this proves successful, Aβ vaccination could provide the first definitive treatment for AD.
Intra- and interspecific competition between biotypes B and Q of Bemisia tabaci (Hemiptera: Aleyrodidae) from Spain
Authors: Pascual S. , Callejas C.
Published: August 2004

Biotypes B and Q of Bemisia tabaci (Gennadius), collected from the islands of Tenerife and Majorca respectively, were exposed to competition conditions on tomato cv. Marmande in the laboratory. Both biotypes were established in single and mixed cultures at different densities. Increased mortality of biotype Q females and immature instars was observed together with a lower rate of fecundity and progeny size compared to biotype B, when reared in single or mixed cultures. The female:male sex ratio of F1 individuals of biotype Q was higher in single than in mixed cultures. However, the sex ratio of F1 individuals of biotype B was the same in single and mixed cultures, suggesting reproductive interference. Whitefly density did not affect interspecific interactions. It had a moderate effect on developmental rate of both biotypes, and on mortality of immature instars and progeny size of biotype B only. The results indicate that under laboratory conditions the studied biotype B should displace biotype Q.
Winter survival of nuisance fly parasitoids (Hymenoptera: Pteromalidae) in Canada and Denmark
Authors: Floate K.D. , Skovgård H.
Published: August 2004

Independent studies were performed in Canada and in Denmark to assess the survival of parasitic wasps (Hymenoptera: Pteromalidae) wintering in puparia of house fly,Musca domesticaLinnaeus (Diptera: Muscidae). Data in Canada were collected forMuscidifurax raptorGirault & Saunders,M. raptorellusKogan & Legner,M. zaraptorKogan & Legner,Nasonia vitripennis(Walker),Spalangia cameroniPerkins,Trichomalopsis sarcophagae(Gahan) andUrolepis rufipes(Ashmead) in three microsites at an outdoor cattle facility in southern Alberta. Survival was highest forN. vitripennis,T. sarcophagaeandU. rufipes, ranging from near zero toc. 7%. No survival was observed forS. cameroni. Daily mean values for ambient air temperature (DMAT) averaged about −3.5°C during exposure periods. Data for Denmark were collected forM. raptor,S. cameroniandU. rufipesin a dairy barn and in a swine barn. Survival ofM. raptorandU. rufipeswas higher than that ofS. cameroniin the dairy barn (DMAT = 8.6°C), with the three species having similar survival in the swine barn (DMAT = 15.4°C). In both studies, parasitoids in egg stages were least likely to survive. These results identify the potential forT. sarcophagaeandU. rufipesto be commercialized for use in northern climates as biocontrol agents for nuisance flies, compare directly the cold-hardiness of commercialized species (i.e. all of the above species excludingT. sarcophagaeandU. rufipes), and document the importance of microsite on winter survival.
An analysis of using entomopathogenic nematodes against above-ground pests
Authors: Arthurs S. , Heinz K.M. , Prasifka J.R.
Published: August 2004

Applications of entomopathogenic nematodes in the families Steinernematidae and Heterorhabditidae have traditionally been targeted against soil insects. Nonetheless, research over the last two decades highlights the potential of such agents against above-ground pests under certain circumstances. A general linear model was used to test for patterns in efficacy among 136 published trials with Steinernema carpocapsae Weiser, the most common species applied against foliar and other above-ground pests. The focus was on field and greenhouse assessments, rather than laboratory assays where relevant ecological barriers to infection are typically removed. The model showed differences in nematode treatment efficacy depending on the pests’ target habitat (bore holes > cryptic foliage > exposed foliage) and trial location (greenhouse > field studies). Relative humidity and temperature during and up to 8 h post-application were also predicted to influence rates of nematode infection obtained. Conversely, spray adjuvants (both wetting agents and anti-desiccants) and nematode dosage applied (both concentration and use of consecutive applications 3–4 days apart) did not explain a significant amount of variance in nematode performance. With reference to case studies the model is used to discuss the relative importance of different factors on nematode efficacy and highlight priorities for workers considering using entomopathogenic nematodes to target pests in novel environments.
Feeding and oviposition rates in the pine weevil Hylobius abietis (Coleoptera: Curculionidae)
Authors: Bylund H. , Nordlander G. , Nordenhem H.
Published: August 2004

Feeding and oviposition in the pine weevil Hylobius abietis (Linnaeus) were monitored under laboratory conditions in two long-term experiments lasting over an extended breeding season. Data were also collected from weevils under semi-natural conditions outdoors. In addition, the effects of crowding and starvation were studied in separate experiments. During the main peak oviposition period, female H. abietis consumed 50% more bark tissue than males. When oviposition ceased, the feeding rate of the females declined to the same level as in the males. The rates and spatial distribution patterns of oviposition and feeding were clearly affected by climatic conditions and the degree of crowding. Females were estimated to lay on average 0.8 eggs per day during the season under outdoor conditions. The realized fecundity of a female weevil during the first season was estimated to be approximately 70 eggs. The estimated average rate of feeding was 23 mm2 of Scots pine bark per weevil per day. This implies that planted seedlings can only constitute a minor part of the food resources needed to sustain H. abietispopulations of the size that usually appear on fresh clear-cuttings in northern Europe.
Biological differences reflect host preference in two parasitoids attacking the bark beetle Ips typographus (Coleoptera: Scolytidae) in Belgium
Authors: Hougardy E. , Grégoire J.-C.
Published: August 2004

The basic reproductive biology of two ectoparasitoids developing on the late larval instars of the scolytid Ips typographus Linnaeus, a pest of spruce forests in Eurasia, was studied with the purpose of explaining which biological features allow the two species to share the same host. The anautogenous braconid Coeloides bostrichorum Giraud had a longer pre-oviposition period (5.1 vs. 3.3 days), a greater egg load (8.1 vs. 6.1 eggs), survived longer and emerged later than the pteromalid Rhopalicus tutela (Walker). In contrast, R. tutela was autogenous and tended to be more fecund under constrained conditions (9.7 vs. 5.1 total offspring per female). The longer pre-oviposition period of the specialist C. bostrichorum, coupled with its greater longevity, afforded the opportunity of better synchronization of ovipositing females with late instar larvae of I. typographus. By contrast, the polyphagous R. tutela matured rapidly, allowing parasitism of both younger and older larval instars of I. typographus in addition to other species. These small differences favoured the co-occurrence of the two parasitoid species on the same attacked trees.
Automated identification of field-recorded songs of four British grasshoppers using bioacoustic signal recognition
Authors: Chesmore E.D. , Ohya E.
Published: August 2004

Recognition of Orthoptera species by means of their song is widely used in field work but requires expertise. It is now possible to develop computer-based systems to achieve the same task with a number of advantages including continuous long term unattended operation and automatic species logging. The system described here achieves automated discrimination between different species by utilizing a novel time domain signal coding technique and an artificial neural network. The system has previously been shown to recognize 25 species of British Orthoptera with 99% accuracy for good quality sounds. This paper tests the system on field recordings of four species of grasshopper in northern England in 2002 and shows that it is capable of not only correctly recognizing the target species under a range of acoustic conditions but also of recognizing other sounds such as birds and man-made sounds. Recognition accuracies for the four species of typically 70–100% are obtained for field recordings with varying sound intensities and background signals.
Phase-related morphological changes induced by [His7]-corazonin in two species of locusts, Schistocerca gregaria and Locusta migratoria (Orthoptera: Acrididae)
Authors: Maeno K. , Gotoh T. , Tanaka S.
Published: August 2004

The effects of a neurohormone, [His7]-corazonin, on phase-related morphological traits (F/C and E/F ratios; F = length of the hind femur, C = maximum width of the head; E = length of fore wing) were re-examined in the desert locust, Schistocerca gregaria Forskål. The F/C ratio was significantly different between adults with five and six nymphal instars, respectively, indicating that they need to be analysed separately. Injections of the synthesized peptide (1 nmol) into individually-reared (solitary) nymphs at the second and third instars caused a shift in classical morphometric ratio towards the value typical for crowded (gregarious) individuals in both sexes. The E/F ratio, which is smaller in solitary locusts than in gregarious ones, was also influenced significantly by injections of [His7]-corazonin into individually-reared locusts. The effect of [His7]-corazonin on E/F ratios was shown more clearly when the nymphs were injected at a higher dose (2 nmol) at the beginning of the third instar. Single injections of the peptide into individually-reared nymphs at different instars revealed that the earlier the injection the larger the ‘gregarizing’ effects of the peptide on F/C and E/F ratios. The same tendency was also detected in Locusta migratoria Linnaeus. These results supported the hypothesis that [His7]-corazonin plays an important role in the control of phase polymorphism in locusts.
Influence of temperature on the development, reproduction and longevity ofCeratothripoides claratris(Thysanoptera: Thripidae) on tomatoes
Authors: Premachandra W.T.S.D. , Borgemeister C. , Chabi-Olaye A. , Poehling H.-M.
Published: August 2004

Ceratothripoides claratris(Shumsher) is a serious pest attacking tomatoes in Thailand. Temperature-dependent development ofC. claratriswas studied at seven constant temperatures, i.e. 22, 25, 27, 30, 34, 35 and 40°C. Pre-adult survivorship was greatest (95%) at 25 and 30°C and shortest at 22°C. Egg-to-adult time decreased within the range of 20 to 30°C and at 34°C it started to increase. The lower thermal threshold for egg-to-adult development was estimated at 16 and 18°C by linear regression and the modified Logan model, respectively. The optimum temperature for egg-to-adult development was estimated at 32–33°C by the modified Logan model. The influence of temperature on reproduction and longevity ofC. claratriswas determined at 25, 30 and 35 and 40°C. Both inseminated and virgin females failed to reproduce at 40°C. Virgin females produced only male offspring, confirming arrhenotoky. The sex ratio of the offspring of fertilized females was strongly female-biased, except at 25°C. Mean total fecundity per female and mean daily total fecundity per female were highest for both virgin and inseminated females at 30°C. Female longevity was longest at 25°C and shortest at 40°C. Male longevity was longest at 30°C and shortest at 40°C. The net reproductive rate (R0) and intrinsic rate of natural increase (rm) was greatest at 30°C while, mean generation time (G) and the doubling time (t) were highest at 25°C. The finite rate of increase (λ) was fairly constant (1.1–1.5 days) over the three temperatures tested. The pest potential ofC. claratrisfor tropical Asia is discussed.
Factors affecting abundance and oviposition rates of a field population of the Old World screw-worm fly, Chrysomya bezziana (Diptera: Calliphoridae)
Authors: Mahon R.J. , Ahmad H. , Wardhaugh K.G.
Published: August 2004

Sentinel cattle and a grid of swormlure-baited sticky traps were used to monitor a Malaysian population of the Old World screw-worm fly, Chrysomya bezziana Villeneuve. Observations were carried out on an isolated cattle station at monthly intervals during the period August 1996 to June 2000. The number of flies caught was unaffected by weather conditions at the time of trapping, but was positively correlated with the total rainfall and the average daily air temperature prevailing 15–28 days earlier, when trapped flies were still juveniles. Trap catches were biased in favour of females, but daily catch rates of both sexes increased significantly the longer traps were open, suggesting that efficacy was related to the differential volatility of the chemicals comprising swormlure. Oviposition on sentinel cattle occurred mostly in late afternoon or early evening but increased significantly as the wound aged. Oviposition rates were positively correlated with female catch rates, but the relationship was curvilinear, suggesting that fly populations may be subject to some form of density-dependent constraint. Consistent differences in oviposition rates on sentinel cattle at different localities on the cattle station suggested the existence of highly clumped, quasi-stationary populations. Differences in trap catches between traps located in pastoral areas and those sited in nearby oil palm or rubber plantations supported this interpretation of the data. These findings are discussed in relation to the use of the sterile insect technique for the control of screw-worm fly infestations.
The role of acculturation in the emerging adulthood of aboriginal college students
Authors: Cheah Charissa S. L. , Nelson Larry J.
Published: August 2004

Compared to traditional, non-Western cultures, emerging adulthood (18–25 years of age) may look considerably different in cultures that place emphasis on the group (i.e., collectivistic) over the individual (i.e., individualistic). However, within minority cultures, individual members vary on the extent to which they identify with their heritage culture. Thus, the purpose of this study was to explore the role that culture, particularly acculturation to Canadian aboriginal heritage culture, may play in emerging adulthood. Specifically, aboriginal emerging adults who scored above or below the mean of their peers on acculturation to their heritage (aboriginal) culture were compared to their majority European Canadian counterparts in several aspects of emerging adulthood including (a) perceived adult status, (b) perceived criteria for adulthood, (c) achieved criteria for adulthood, (d) personal beliefs about the future, and (e) risk behaviours. Results revealed the significance of examining acculturation in understanding the role of culture in the process of emerging adulthood, particularly among ethnic minority youth. In particular, findings revealed that young aboriginal adults’ level of identification with aboriginal traditions such as the significance of interdependence and maintenance of harmony, the role of children and family, and historical sociocultural events appeared to play a role in many aspects of emerging adulthood.
Memory for Proper Names in Old Age: A Disproportionate Impairment?
Authors: Rendell Peter G. , Castel Alan D. , Craik Fergus I. M.
Published: August 2004

A common complaint of older adults is that they have trouble remembering names, even the names of people they know well. Two experiments examining this problem are reported in the present article. Experiment 1 tested episodic memory for surnames and occupations; older adults and younger adults under divided attention performed less well than did full attention younger adults, but showed no disproportionate loss of name information. Experiment 2 examined the ability to name photographs of public figures and of uncommon objects; this experiment therefore tested retrieval from semantic memory. In this case adults in their 70s did show an impairment in recall of names of known people, but not of known objects. Further analyses revealed systematic relations between naming, recognition, and rated familiarity of the categories used. Familiarity largely determined the proportions of recognizable items that were named in a prior phase. Overall, little evidence was found for a disproportionate age-related impairment in naming in either episodic or semantic memory.
Processing Speed, Executive Function, and Age Differences in Remembering and Knowing
Authors: Bunce David , Macready Anna
Published: August 2004

A group of young ( n = 52, M = 23.27 years) and old ( n = 52, M = 68.62 years) adults studied two lists of semantically unrelated nouns. For one list a time of 2 s was allowed for encoding, and for the other, 5 s. A recognition test followed where participants classified their responses according to Gardiner's (1988) remember-know procedure. Age differences for remembering and knowing were minimal in the faster 2-s encoding condition. However, in the longer 5-s encoding condition, younger persons produced significantly more remember responses, and older adults a greater number of know responses. This dissociation suggests that in the longer encoding condition, younger adults utilized a greater level of elaborative rehearsal governed by executive processes, whereas older persons employed maintenance rehearsal involving short-term memory. Statistical control procedures, however, found that independent measures of processing speed accounted for age differences in remembering and knowing and that independent measures of executive control had little influence. The findings are discussed in the light of contrasting theoretical accounts of recollective experience in old age.
Age-Related Declines in Context Maintenance and Semantic Short-Term Memory
Authors: Haarmann Henk J. , Ashling Gemma E. , Davelaar Eddy J. , Usher Marius
Published: August 2004

This study reports age-related declines in context maintenance ( Braver et al., 2001 ) and semantic short-term memory (STM) and evidence for a relation between the two. A group of younger and older adults completed a context maintenance task (AX-CPT), a semantically oriented STM task (conceptual span), a phonologically oriented STM task (digit span), and a meaning integration task (semantic anomaly judgement). In the AX-CPT task, a target response is required to the probe letter “X” but only when it is preceded by the letter “A” (the context). Either three (short interference) or six distractor letters (long interference) were presented between the cue and the probe. Results indicated an age-related deficit in context maintenance. Age-related declines were also observed for conceptual span and semantic anomaly judgement but not for digit span. Context maintenance was correlated with conceptual span and semantic anomaly judgement but not with digit span. These correlations were largely mediated by age differences, which also explained variance that was unique to (and not shared among) context maintenance, conceptual span, and semantic anomaly judgement.
Age-Related Deficits in Free Recall: The Role of Rehearsal
Authors: Ward Geoff , Maylor Elizabeth A.
Published: August 2004

Age-related deficits have been consistently observed in free recall. Recent accounts of episodic memory suggest that these deficits could result from differential patterns of rehearsal. In the present study, 20 young and 20 older adults (mean ages 21 and 72 years, respectively) were presented with lists of 20 words for immediate free recall using the overt rehearsal methodology. The young outperformed the older adults at all serial positions. There were significant age-related differences in the patterns of overt rehearsals: Young adults rehearsed a greater number of different words than did older adults, they rehearsed words to more recent serial positions, and their rehearsals were more widely distributed throughout the list. Consistent with a recency-based account of episodic memory, age deficits in free recall are largely attributable to age differences in the recency, frequency, and distribution of rehearsals.
Biomarkers, Health, Lifestyle, and Demographic Variables as Correlates of Reaction Time Performance in Early, Middle, and Late Adulthood
Authors: Anstey Kaarin J. , Dear Keith , Christensen Helen , Jorm Anthony F.
Published: August 2004

We aimed to identify demographic, health, and biomarker correlates of reaction time performance and to determine whether biomarkers explained age differences in reaction time performance. The sample comprised three representative cohorts aged 20–24, 40–44, and 60–64 years, including a total of 7,485 participants. Reaction time measures of intraindividual variability and latency were used. The measure of intraindividual variability used was independent of mean reaction time. Older adults were more variable than younger adults in choice reaction time performance but not simple reaction time performance. The most important correlates of reaction time performance after gender and education were biological markers such as forced expiratory volume at one second, grip strength, and vision. Few measures of physical or mental health or lifestyle were associated with poorer performance on reaction time measures. Biomarkers explained the majority of age-related variance in simple reaction time and a large proportion of variance in choice reaction time. We conclude that for the ages studied, biomarkers are more important than health factors for explaining age differences in reaction time performance.
Goals or horizons—the conundrum of progression in English: or a possible way of understanding formative assessment in English
Authors: Marshall Bethan
Published: August 2004

This article examines how the principles of formative assessment might be applied to the curriculum subject of English. It takes as its starting point the problematic nature of progression in the subject and suggests that it may be better to understand progression as heading towards a horizon rather than a clearly defined goal. The article argues this by exploring the potential constraints of what might be considered goal models of progression and contrasts these with the affordances offered by those approaches that view progression as towards a horizon. In particular it suggests that, in order to understand how to progress, pupils need to acquire the guild subject knowledge of their teachers by being apprenticed into the same community of interpreters. The article situates this discussion within wider concerns about how teachers scaffold and regulate the learning process for their pupils.
ICT and pupil assessment
Authors: McCormick Robert
Published: August 2004

The role of pupil assessment in ICT is often seen by teachers as problematic. This article will explore the relationship of the two and will argue that research in assessment has not kept up with the opportunities offered by ICT. Conversely, some of the new developments in ‘assessment for learning’ have not yet found their way into ICT. The article will explore the various roles and relationships that ICT has in assessment, for example, the assessment of ICT skills, the assessment of curriculum learning when work is done with the aid of ICT, assessment within computer‐assisted learning, and ICT as a tool in supporting the assessment process in general. It will also look at ways forward, including ‘assessment for learning’ (with its concern for questioning, feedback, sharing assessment criteria and self‐assessment/peer assessment), and new outcomes that could be in­corporated into ICT.
Access and use of technologies in the home in the UK: implications for the curriculum
Authors: Lewin Cathy
Published: August 2004

This article reports on research undertaken as part of the government initiatives to transform educational practices and raise standards through new technologies. In particular, it focuses on differences between home and school experiences of ICT use and formal/informal learning opportunities. First, the issues arising from the growing body of research‐based evidence in this field are considered. Second, a discussion of the analysis of three sources of data from the ImpaCT2 project is presented: a pupil log of ICT activity undertaken at home and at school over a period of one week (including a weekend); an internet questionnaire about home and school uses for both school work and leisure pursuits; and a concept mapping task to ascertain pupils’ understanding of computers in their world. The article concludes by considering the implications for the curriculum of home experiences of ICT and the benefits of informal learning with ICT.
Fostering of creativity within an imaginative curriculum in higher education
Authors: Donnelly Roisin
Published: August 2004

Psychology is frequently used as a foundation discipline in the training of adult educators because it addresses those questions which naturally emerge from an engagement with adult learning and teaching (Tennant, 1997). The professional context which forms the focus of this article is no different. By providing academic support for lecturers in a higher education institution in Ireland, there is a desire to develop a sustainable curriculum model whereby by working with them on designing and developing creative curricula in their various subject disciplines in the arts and sciences they, in turn, pass the benefits of this on to their students.