bluuebunny/crossref_metadata_2025_split huggingface dataset:
Population ecology of polar bears at Svalbard, Norway
Authors: Derocher Andrew E. 
Published: September 2005

AbstractThe population ecology of polar bears at Svalbard, Norway, was examined from 1988 to 2002 using live‐captured animals. The mean age of both females and males increased over the study, litter production rate and natality declined and body length of adults decreased. Dynamics of body mass were suggestive of cyclical changes over time and variation in body mass of both adult females and adult males was related to the Arctic Oscillation index. Similarly, litter production rate and natality correlated with the Arctic Oscillation index. The changes in age‐structure, reproductive rates and body length suggest that recovery from over‐harvest continued for almost 30 years after harvest ended in 1973 and that density‐dependent changes are perhaps being expressed in the population. However, the variation in reproduction and body mass in the population show a relationship between large‐scale climatic variation and the upper trophic level in an Arctic marine ecosystem. Similar change in other polar bear populations has been attributed to climate change, and further research is needed to establish linkages between climate and the population ecology of polar bears.
Racism, psychosis and common mental disorder among ethnic minority groups in England
Authors: KARLSEN SAFFRON , NAZROO JAMES Y. , McKENZIE KWAME , BHUI KAMALDEEP , WEICH SCOTT 
Published: September 2005

Background. The aim of this study was to explore the relationship between risk of psychosis, common mental disorder (CMD) and indicators of racism among ethnic minority groups in England and how this relationship may vary by particular ethnic groups.Method. A multivariate analysis was carried out of quantitative, cross-sectional data from a nationally representative community sample of people aged between 16 and 74 years from the largest ethnic minority groups in England: those of Caribbean, Indian, Pakistani, Bangladeshi and Irish origin.Results. Experience of interpersonal racism and perceiving racism in the wider society each have independent effects on the risk of CMD and psychosis, after controlling for the effects of gender, age and socio-economic status. There was some variation in the findings when they were conducted for separate ethnic and gender groups.Conclusions. An understanding of the relationship between racism and mental health may go some way towards explaining the ethnic variations found in both CMD and, particularly, psychosis.
Does provider adherence to a treatment guideline change clinical outcomes for patients with bipolar disorder? Results from the Texas Medication Algorithm Project
Authors: DENNEHY ELLEN B. , SUPPES TRISHA , RUSH A. JOHN , MILLER ALEXANDER L. , TRIVEDI MADHUKAR H. , CRISMON M. LYNN , CARMODY THOMAS J. , KASHNER T. MICHAEL 
Published: September 2005

Background. Despite increasing adoption of clinical practice guidelines in psychiatry, there is little measurement of provider implementation of these recommendations, and the resulting impact on clinical outcomes. The current study describes one effort to measure these relationships in a cohort of public sector out-patients with bipolar disorder.Method. Participants were enrolled in the algorithm intervention of the Texas Medication Algorithm Project (TMAP). Study methods and the adherence scoring algorithm have been described elsewhere. The current paper addresses the relationships between patient characteristics, provider experience with the algorithm, provider adherence, and clinical outcomes. Measurement of provider adherence includes evaluation of visit frequency, medication choice and dosing, and response to patient symptoms. An exploratory composite ‘adherence by visit’ score was developed for these analyses.Results. A total of 1948 visits from 141 subjects were evaluated, and utilized a two-stage declining effects model. Providers with more experience using the algorithm tended to adhere less to treatment recommendations. Few patient factors significantly impacted provider adherence. Increased adherence to algorithm recommendations was associated with larger decreases in overall psychiatric symptoms and depressive symptoms over time, but did not impact either immediate or long-term reductions in manic symptoms.Conclusions. Greater provider adherence to treatment guideline recommendations was associated with greater reductions in depressive symptoms and overall psychiatric symptoms over time. Additional research is needed to refine measurement and to further clarify these relationships.
Problem-solving ability and repetition of deliberate self-harm: a multicentre study
Authors: McAULIFFE CARMEL , CORCORAN PAUL , KEELEY HELEN S. , ARENSMAN ELLA , BILLE-BRAHE UNNI , De LEO DIEGO , FEKETE SANDOR , HAWTON KEITH , HJELMELAND HEIDI , KELLEHER MARGARET , KERKHOF AD J.F.M. , LÖNNQVIST JOUKO , MICHEL KONRAD , SALANDER-RENBERG ELLINOR , SCHMIDTKE ARMIN , VAN HEERINGEN KEES , WASSERMAN DANUTA 
Published: September 2005

Background. While recent studies have found problem-solving impairments in individuals who engage in deliberate self-harm (DSH), few studies have examined repeaters and non-repeaters separately. The aim of the present study was to investigate whether specific types of problem-solving are associated with repeated DSH.Method. As part of the WHO/EURO Multicentre Study on Suicidal Behaviour, 836 medically treated DSH patients (59% repeaters) from 12 European regions were interviewed using the European Parasuicide Study Interview Schedule (EPSIS II) approximately 1 year after their index episode. The Utrecht Coping List (UCL) assessed habitual responses to problems.Results. Factor analysis identified five dimensions – Active Handling, Passive-Avoidance, Problem Sharing, Palliative Reactions and Negative Expression. Passive-Avoidance – characterized by a pre-occupation with problems, feeling unable to do anything, worrying about the past and taking a gloomy view of the situation, a greater likelihood of giving in so as to avoid difficult situations, the tendency to resign oneself to the situation, and to try to avoid problems – was the problem-solving dimension most strongly associated with repetition, although this association was attenuated by self-esteem.Conclusions. The outcomes of the study indicate that treatments for DSH patients with repeated episodes should include problem-solving interventions. The observed passivity and avoidance of problems (coupled with low self-esteem) associated with repetition suggests that intensive therapeutic input and follow-up are required for those with repeated DSH.
Adolescent alcohol use is a risk factor for adult alcohol and drug dependence: evidence from a twin design
Authors: GRANT JULIA D. , SCHERRER JEFFREY F. , LYNSKEY MICHAEL T. , LYONS MICHAEL J. , EISEN SETH A. , TSUANG MING T. , TRUE WILLIAM R. , BUCHOLZ KATHLEEN K. 
Published: September 2005

Background. Early alcohol use is associated with abuse and dependence of licit and illicit substances later in life. The role of genetic and environmental factors in this association is not conclusive.Method. In 1992, data on substance use, abuse/dependence and psychiatric disorders were collected from 8169 male twin members of the Vietnam Era Twin Registry. The interview obtained age of onset of regular drinking (one drink/month for 6 or more months). Regression analyses of twin pairs discordant for early alcohol use tested whether the association between early drinking (before age 17) and adult substance use and abuse/dependence remained after controlling for genetic factors, family environment and covariates. Twin models tested for common genetic and/or environmental influences on early drinking and adult alcohol dependence and ever use and abuse/dependence on marijuana and other drugs.Results. Co-twin analyses suggested the association between early regular alcohol use and adult alcohol dependence, marijuana and other drug use, and marijuana and other drug abuse/dependence could not be entirely explained by common genetic and shared family environmental factors. Genetic contributions to early regular drinking were significantly correlated with those on use of marijuana (rA=0·59), use of other drugs (rA=0·64), alcohol dependence (rA=0·54) and abuse/dependence of marijuana and other drugs (rA=0·63 and 0·66). Small but significant unique environmental correlations (rE range 0·11–0·22) indicated that familial factors could not entirely explain the association between early alcohol use and later substance use, abuse and dependence.Conclusions. Early regular drinking is associated with later alcohol dependence and use, abuse/dependence on drugs. The association is not entirely explained by genetic or shared family environmental factors. This suggests unique environmental factors contribute to transitions from early regular alcohol drinking to use, abuse and dependence on alcohol and other substances.
Host-plant finding by the asparagus fly, Plioreocepta poeciloptera (Diptera: Tephritidae), a monophagous, monovoltine tephritid
Authors: Thibout É , Pierre D. , Mondy N. , Lecomte C. , Biémont J.C. , Auger J. 
Published: September 2005

AbstractThe role of various olfactory and visual stimuli was studied in host-plant finding by the asparagus fly Plioreocepta poeciloptera (Schrank), a monophagous monovoltine tephritid causing serious damage to asparagus spears. Volatiles released by asparagus plants were extracted by diethyl ether after cryotrapping concentration, and identified by gas chromatography–mass spectrometry. Twelve of the 13 compounds identified were tested using electroantennography to measure the response of the fly. Behavioural response was analysed using two different flight tunnels according to circadian rhythm, age and sex of adults, presence of the plant and of different coloured lures, presence of a male congener, or exposure to four pure asparagus odour compounds that elicited responses in electroantennography, i.e. hexanal, (E)-2-hexenal, (Z)-2-hexen-1-ol and decanal. Data showed that males locate the host plant more quickly than females. Females are attracted mainly by the blend of plant odour and male pheromone. Both sexes respond to a complex of stimuli only during the afternoon. These findings will be helpful in developing new and effective approaches to control this pest insect.
Hybridization between Helicoverpa armigera and Helicoverpa assulta (Lepidoptera: Noctuidae): development and morphological characterization of F1 hybrids
Authors: Zhao X.-C. , Dong J.-F. , Tang Q.-B. , Yan Y.-H. , Gelbic I. , Van Loon J.J.A. , Wang C.-Z. 
Published: September 2005

AbstractReciprocal hybridizations between Helicoverpa armigera (Hübner) and Helicoverpa assulta (Guenée) were studied. The cross between females of H. armigera and males of H. assulta yielded only fertile males and sterile individuals lacking an aedeagus, valva or ostium bursae. A total of 492 larvae of the F1 generation were obtained and 374 of these completed larval development and pupated. Only 203 pupae were morphologically normal males, the remaining 171 pupae were malformed. Larvae and pupae that gave rise to morphologically abnormal adults exhibited longer development times. Sterility was not only associated with malformed external sex organs, but also a range of abnormalities of the internal reproductive system: (i) loss of internal reproductive organs, (ii) with one to three copies of an undeveloped bursa copulatrix; or (iii) with one or two undeveloped testes. Normal male hybrid adults showed higher flight activity in comparison with males of both species. In contrast, the cross between females of H. assulta and males of H. armigera yielded morphologically normal offspring (80 males and 83 females). The interaction of the Z-chromosome from H. assulta with autosomes from H. armigera might result in morphological abnormalities found in hybrids and backcrosses, and maternal-zygotic incompatibilities might contribute to sex bias attributed to hybrid inviability.
Relationships of intercropped maize, stem borer damage to maize yield and land-use efficiency in the humid forest of Cameroon
Authors: Chabi-Olaye A. , Nolte C. , Schulthess F. , Borgemeister C. 
Published: September 2005

AbstractStem borers are the most important maize pests in the humid forest zone of Cameroon. Field trials were conducted in the long and short rainy seasons of 2002 and 2003 to assess the level of damage and yield reductions caused by stem borers in monocropped maize and in maize intercropped with non-host plants such as cassava, cowpea and soybean. The intercrops were planted in two spatial arrangements, i.e. alternating hills or alternating rows. All intercrops and the maize monocrop were grown with and without insecticide treatment for assessment of maize yield loss due to borer attacks. The land-use efficiency of each mixed cropping system was evaluated by comparing it with the monocrop. The temporal fluctuation of larval infestations followed the same pattern in all cropping systems, but at the early stage of plant growth, larval densities were 21.3–48.1% higher in the monocrops than in intercrops, and they tended to be higher in alternating rows than alternating hills arrangements. At harvest, however, pest densities did not significantly vary between treatments. Maize monocrops had 3.0–8.8 times more stems tunnelled and 1.3–3.1 times more cob damage than intercrops. Each percentage increase in stem tunnelling lowered maize grain yield by 1.10 and 1.84 g per plant, respectively, during the long and short rainy season in 2002, and by 5.39 and 1.41 g per plant, respectively, in 2003. Maize yield losses due to stem borer were 1.8–3.0 times higher in monocrops than in intercrops. Intercrops had generally a higher land-use efficiency than monocrops, as indicated by land-equivalent-ratios and area-time-equivalent-ratios of >1.0. Land-use efficiency was similar in both spatial arrangements. At current price levels, the net production of mixed cropping systems was economically superior to controlling stem borers with insecticide in monocropped maize. The maize–cassava intercrop yielded the highest land equivalent ratios and the highest replacement value of the intercrop. At medium intensity cropping this system is thus recommended for land-constrained poor farmers who do not use external inputs such as fertilizer and insecticides.
Role of host feeding niches and host refuges in habitat-related behaviour of Hyssopus pallidus (Hymenoptera: Eulophidae), a larval parasitoid of the codling moth
Authors: Hausmann C. , Mattiacci L. , Dorn S. 
Published: September 2005

AbstractParasitoid fitness depends largely on the capability to locate a host in an ecosystem. A parasitoid of a polyphagous host might not be able to find or to access the host in all its feeding niches. This study evaluated the niche selection of Hyssopus pallidus (Askew), a larval parasitoid of Cydia pomonella (Linnaeus), at the plant level with the goal of assessing its potential for biological control on different fruit crops throughout the plant cycle. Parasitoid behaviour during host location and reproduction rate were investigated on host caterpillars actively feeding on apple, pear, apricot or plum, and on caterpillars diapausing under the bark. Under laboratory conditions, the host searching behaviour of H. pallidus varied depending on the fruit species offered and the infestation of the fruits. Parasitoid females searched longer on apples than on other fruit species, and they searched longer on infested than on uninfested apples. Female wasps were able to locate and parasitize host caterpillars under the tree bark, and their behaviour did not vary with host accessibility. The numbers of caterpillars attacked by H. pallidus depended on the fruit species. The highest numbers of caterpillars were parasitized in apples and apricots. Their accessibility (i.e. position) within the fruit or on the branch did not influence parasitism success. Although hosts were parasitized throughout the season, the best results were achieved with early and late releases. Therefore, the host niche selection behaviour of H. pallidus most likely co-evolved with the host C. pomonella on apples, which renders H. pallidus a valuable biocontrol agent for successful release at different times of the season into apple orchards.
Behavioural responses of diamondback mothPlutella xylostella(Lepidoptera: Plutellidae) to extracts derived fromMelia azedarachandAzadirachta indica
Authors: Charleston D.S. , Kfir R. , Vet L.E.M. , Dicke M. 
Published: September 2005

AbstractThe impact of three different doses of botanical insecticide derived from the syringa tree,Melia azedarachand the neem tree,Azadirachta indicawas tested on the behaviour of the diamondback moth,Plutella xylostella(Linnaeus). Both botanical insecticides had a significant impact on larval behaviour. At higher doses the extracts showed feeding deterrent activity, with larvae preferring the untreated sides of cabbage leaves and consuming less of the treated half of cabbage leaves. The botanical insecticides had less of an effect on the oviposition behaviour ofP. xylostellamoths. In laboratory and glasshouse trials, significantly fewer eggs were oviposited on the plants that had been treated with syringa extracts. Therefore, the syringa extracts appear to have a repellent effect. In contrast, when exposed to the neem extracts the moths did not discriminate between control plants and treated plants. Behavioural observation indicated that, despite the lower number of eggs oviposited on cabbage treated with syringa extracts, the moths chose cabbage treated with the highest dose of syringa more often than they chose control cabbage plants. Similar observations were found in cabbage plants treated with neem, moths chose the medium dose more often than they chose the control. Oviposition and feeding deterrent properties are important factors in pest control, and results from this study indicate that botanical insecticides have the potential to be incorporated into control programmes forP. xylostellain South Africa.
Biological control of the coffee berry borerHypothenemus hampei(Coleoptera: Curculionidae) byPhymastichus coffea(Hymenoptera: Eulophidae) in Colombia
Authors: Jaramillo J. , Bustillo A.E. , Montoya E.C. , Borgemeister C. 
Published: September 2005

AbstractThe potential of the eulophid parasitoidPhymastichus coffeaLaSalle to control coffee berry borerHypothenemus hampei(Ferrari) populations under field conditions in Colombia was evaluated. Parasitoid adults were released one, five and nine days after artificial infestations of 90-, 150- and 210-day-old coffee berries withH. hampeifemales. The position of the beetle inside the berry and the parasitism levels were assessed ten days after eachP. coffearelease. Parasitism ofH. hampeibyP. coffeawas significantly affected by the age of the berries at the time of infestation, and by the position of the beetle inside the berries. Highest levels of parasitism were recorded in 150-day-old berries (75–85%) and in 90-day-old berries (75%) whenP. coffeawere released one day after the artificial infestation withH. hampei. In 150-day-old berries, highest levels of parasitism were recorded forH. hampeifound in the outer layer of the endosperm followed by beetles penetrating the exocarp. Increasing the time ofP. coffeareleases after the artificial infestations withH. hampeiled to decreased levels of parasitism in beetles attacking 90- and 150-day-old coffee berries. Low levels of parasitism were recorded inH. hampeifemales infesting older coffee berries because most of the beetles had already constructed galleries deep in the endosperm of the berries, i.e. out of reach of the parasitoid. The potential ofP. coffeafor biological control of coffee berry borer in Colombia is discussed.
Screening of entomopathogenic nematodes for virulence against the invasive western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae) in Europe
Authors: Toepfer S. , Gueldenzoph C. , Ehlers R.-U. , Kuhlmann U. 
Published: September 2005

AbstractEntomopathogenic nematode species available in Europe were screened for their efficacy against both the root-feeding larvae and silk-feeding adults of the western corn rootworm, Diabrotica virgifera virgifera LeConte. Laboratory screening tests were aimed at the selection of candidate biological control agents for the management of this invasive alien pest in Europe. Steinernema glaseri, S. arenarium, S. abassi, S. bicornutum, S. feltiae, S. kraussei, S. carpocapsae and Heterorhabditis bacteriophora were studied to determine their virulence against third instar larvae and adults of D. v. virgifera in small-volume arenas (using nematode concentrations of 0.5, 0.8, 7.9 and 15.9 infective juveniles cm–2). All nematode species were able to invade and propagate in D. v. virgifera larvae, but adults were rarely infected. At concentrations of 7.9 and 15.9 cm–2, S. glaseri, S. arenarium, S. abassi and H. bacteriophora caused the highest larval mortality of up to 77%. Steinernema bicornutum, S. abassi, S. carpocapsae and H. bacteriophora appeared to have a high propagation level, producing 5970±779, 5595±811, 5341±1177 and 4039±1025 infective juveniles per larva, respectively. Steinernema glaseri, S. arenarium, S. feltiae, S. kraussei and H. bacteriophora were further screened at a concentration of 16.7 nematodes cm–2 against third instar larvae in medium-volume arenas (sand-filled trays with maize plants). Heterorhabditis bacteriophora, S. arenarium and S. feltiae caused the highest larval mortality with 77±16.6%, 67±3.5%, and 57±17.1%, respectively. In a next step, criteria for rating the entomopathogenic nematode species were applied based on results obtained for virulence and propagation, and for current production costs and availability in Europe. These criteria were then rated to determine the potential of the nematodes for further field testing. Results showed the highest potential in H. bacteriophora, followed by S. arenarium and S. feltiae, for further testing as candidate biological control agents.
The attack of the clones: tracking the movement of insecticide-resistant peach–potato aphids Myzus persicae (Hemiptera: Aphididae)
Authors: Fenton B. , Malloch G. , Woodford J.A.T. , Foster S.P. , Anstead J. , Denholm I. , King L. , Pickup J. 
Published: September 2005

AbstractMyzus persicae (Sulzer) collected in Scotland were characterized for four microsatellite loci, intergenic spacer fingerprints and the resistance mechanisms modified acetylcholinesterase (MACE), overproduced carboxylesterase and knockdown resistance (kdr). Microsatellite polymorphisms were used to define a limited number of clones that were either fully susceptible to insecticides or possessed characteristic combinations of resistance mechanisms. Within these clones, intergenic spacer fingerprints could either be very consistent or variable, with the latter indicating ongoing evolution within lineages, most likely derived from the same zygote. Two clones (termed A and B) possessed all three resistance mechanisms and predominated at sites treated with insecticides. Their appearance on seed potatoes and oilseed rape in Scotland in 2001 coincided with extensive insecticide use and severe control failures. Clones C, I and J, with no or fewer resistance mechanisms, were found in samples from 1995 and were dominant at untreated sites in 2001. A comparison of Scottish collections with those from other UK and non-UK sites provides insight into the likely origins, distribution and dynamics of M. persicae clones in a region where asexual (anholocyclic) reproduction predominates, but is vulnerable to migration by novel genotypes from areas of Europe where sexual (holocyclic) reproduction occurs.