bluuebunny/crossref_metadata_2025_split huggingface dataset:
Possible factors contributing to the exclusion of saturniid caterpillars (mopane worms) from a protected area in Botswana
Authors: STYLES C. V. , SKINNER J. D. 
Published: April 2008

SummaryThis paper deals with the local absence of mopane worms, the colloquial name given to caterpillars of the mopane emperor moth Imbrasia belina (Saturniidae), from within the confines of the Northern Tuli Game Reserve (NTGR) of Botswana for at least the last 23 years. Possible factors such as ant predation, edaphic factors and leaf chemistry were studied in an attempt to explain this local absence. Very obvious differences exist, with respect to both ant occurrence and tree leaf chemistry, the ant occurrence and browse quality in the area frequented yearly by the caterpillars being very low and very high respectively when compared with the calculated values for the protected area. A contributing factor to the absence of caterpillars from the NTGR might be extensive utilization of the area's mopane veld by mammalian herbivores and the preponderance of ants, which act as an effective antiherbivory mechanism, on mopane trees. In addition, low rainfall and possibly unsuitable burrowing substrates (soil for pupation) probably contributed.RésuméCet article concerne l'absence locale de vers mopane, nom familier donné aux chenilles du papillon de nuit Imbrasia belina (Saturniidae), aux confins de la Northern Tuli Game Reserve (NTGR), au Botswana, depuis au moins 23 ans. On a étudié des facteurs potentiels tels que la prédation par les fourmis, des facteurs édaphiques, et la chimie du feuillage pour tenter d'expliquer cette absence localisée. II existe des différences tout à fait évidentes, tant en ce qui concerne la présence de fourmis que la chimie du feuillage: la présence des fourmis et la qualité de la nourriture dans la région fréquentée chaque année par les chenilles sont respectivement très elevee et très mauvaise lorsqu'on les compare aux valeurs calculées pour l'aire protégée. Un facteur contribuant aussi à l'absence de chenilles de la NTGR pourrait être l'utilisation extensive de la zone des mopane par des mammifères herbivores et par la prépondérance sur les mopane des fourmis qui pourraient bien agir comme un mécanisme antiherbivore efficace. De plus, il faut ajouter des chutes de pluies faibles et un substrat peut‐être moins propice pour être creusé (pour la ponte).
Breeding and moult cycles in three bulbul (Pycnonotidae) species in coastal Tanzania
Authors: MLINGWA C. O. F. 
Published: April 2008

SummaryThe annual cycles of breeding and moult in three bulbul species are described from a bird ringing study carried out in the period January 1989‐June 1990 and June 1994‐May 1995 in coastal Tanzania. Both breeding and moult are seasonal events. The former takes place from October to May or June, and the latter from January to August or September; hence, there is a marked breeding‐moult overlap. The overlap of breeding and moulting seasons within the population but not within individuals is due to inter‐and intra‐sexual variations in the onset of moult. The ecological significance of this strategy is discussed. The annual cycles of these species are also compared with those of other bulbuls occurring in the same area.RésuméOn décrit les cycles annuels de reproduction et de mue de trois espèces de bulbuls à partir d'une étude de baguage d'oiseux réalisée pendant la période allant de Janvier 1989 à juin 1990 et celle allant de juin 1994 à mai 1995, sur la côte tanzanienne. La reproduction et la mue sont des événements saisonniers. La première a lieu d'octobre à mai ou juin, et la seconde, de Janvier à août ou septembre; il y a done recouvrement marqué entre les périodes de reproduction et de mue. Le recouvrement des saisons de reproduction et de mue à l'intérieur des populations, mais non chez les individus, est dû aux variations inter‐et intrasexuelles du déclenchement de la mue. On discute la signification écologique de cette stratégic On compare aussi les cycles annuels de ces espèces avec ceux d'autres bulbuls vivant dans la même région.
Soil temperature affects carbon allocation within arbuscular mycorrhizal networks and carbon transport from plant to fungus
Authors: HAWKES CHRISTINE V. , HARTLEY IAIN P. , INESON PHIL , FITTER ALASTAIR H. 
Published: April 2008

AbstractHow soil carbon balance will be affected by plant–mycorrhizal interactions under future climate scenarios remains a significant unknown in our ability to forecast ecosystem carbon storage and fluxes. We examined the effects of soil temperature (14, 20, 26 °C) on the structure and extent of a multispecies community of arbuscular mycorrhizal (AM) fungi associated with Plantago lanceolata. To isolate fungi from roots, we used a mesh‐divided pot system with separate hyphal compartments near and away from the plant. A 13C pulse label was then used to trace the flow of recently fixed photosynthate from plants into belowground pools and respiration. Temperature significantly altered the structure and allocation of the AM hyphal network, with a switch from more vesicles (storage) in cooled soils to more extensive extraradical hyphal networks (growth) in warmed soils. As soil temperature increased, we also observed an increase in the speed at which plant photosynthate was transferred to and respired by roots and AM fungi coupled with an increase in the amount of carbon respired per unit hyphal length. These differences were largely independent of plant size and rates of photosynthesis. In a warmer world, we would therefore expect more carbon losses to the atmosphere from AM fungal respiration, which are unlikely to be balanced by increased growth of AM fungal hyphae.
Root competition influences pollen competitive ability inViola tricolor: effects of presence of a competitor beyond resource availability?
Authors: Lankinen Åsa 
Published: April 2008

SummaryIt has recently been suggested that not only nutrients but also presence of a competitor can influence competitive ability in plants, for example, by strategic changes in allocation to roots (a ‘tragedy of the commons’ effect). Such strategic changes might occur also in pollen, because this has potential to increase siring success during pollen competition in the pistil.I tested the new hypothesis that pollen competitive ability – a trait often strongly affected by resources of the pollen parent – was influenced by presence of a root competitor using glasshouse‐grownViola tricolorin 2 years. Plants of two maternal families were combined in pairs with their roots either separated or intermingled in the same amount of resources.Maternal families varied in response to root competition, with pollen performance increasing in some families, decreasing in others and unchanged in others. An increase did not mirror a decrease in the competing family, suggesting an explanation beyond differential ability to gain resources. The responses to competitive environment were often consistent across three independent competitors.There was a positive correlation between family responses in pollen performance and family responses in plant size to root competitors. Larger plants did not produce better pollenper se, indicating that the change in pollen performance was not a pure side effect of altered plant size. There was no support for a ‘tragedy of the commons’ effect on root production. With the experimental design used, an effect of rooting volume could not be completely ruled out.The currently unknown mechanism of the below‐ground interactions between plants ofV. tricolorwas strong enough to change relative pollen competitive ability. These interactions might thus promote variation in the outcome of pollen competition.Synthesis.The results of this study indicate the presence of a competitor on pollen competitive ability beyond the effect of nutrients. Even though the underlying mechanism needs to be explored further, the detected link between pollen competition and soil competition suggests a phenomenon well worth investigating. Further studies may lead to increased understanding of the evolutionary consequences of selection operating in response to interactions with neighbours.
Familial (shared environmental and genetic) factors and the foetal origins of cardiovascular diseases and type 2 diabetes: a review of the literature
Authors: Bergvall N. , Cnattingius S. 
Published: April 2008

Abstract.Several researchers have argued that observed associations between birth weight and cardiovascular diseases, and type 2 diabetes, may be confounded by familial (shared environmental and genetic) factors. However, most studies have found that shared environmental factors, including socio‐economic factors, do not influence the foetal origins of adult diseases. Results from two twin studies suggest that genetic factors may be of importance for the association between birth weight and risks of coronary heart disease, but findings from intergenerational studies are not consistent with genetic confounding. More studies have assessed the importance of genetic factors with respect to risk factors of coronary heart, including raised blood pressure and lipid levels. Recent findings suggest that the association between birth weight and hypertension is independent of genetic factors. In contrast, recent twin and intergenerational studies favour the hypothesis that the association between birth weight and risk of type 2 diabetes is confounded by genetic factors.
YscU cleavage and the assembly of Yersinia type III secretion machine complexes
Authors: Riordan Kelly E. , Schneewind Olaf 
Published: April 2008

SummaryYscU, a component of the Yersinia type III secretion machine, promotes auto‐cleavage at asparagine 263 (N263). Mutants with an alanine substitution at yscU codon 263 displayed secretion defects for some substrates (LcrV, YopB and YopD); however, transport of effector proteins into host cells (YopE, YopH, YopM) continued to occur. Two yscU mutations were isolated that, unlike N263A, completely abolished type III secretion; YscUG127D promoted auto‐cleavage at N263, whereas YscUG270N did not. When fused to glutathione S‐transferase (Gst), the YscU C‐terminal cytoplasmic domain promoted auto‐cleavage and Gst‐YscUC also exerted a dominant‐negative phenotype by blocking type III secretion. Gst–YscUC/N263A caused a similar blockade and Gst–YscUC/G270N reduced secretion. Gst–YscUC and Gst–YscUC/N263A bound YscL, the regulator of the ATPase YscN, whereas Gst–YscUC/G270N did not. When isolated from Yersinia, Gst–YscUC and Gst–YscUC/N263A associated with YscK–YscL–YscQ; however, Gst–YscUC/G270N interacted predominantly with the machine component YscO, but not with YscK–YscL–YscQ. A model is proposed whereby YscU auto‐cleavage promotes interaction with YscL and recruitment of ATPase complexes that initiate type III secretion.
Essential protective role attributed to the surface lipoproteins of Borrelia burgdorferi against innate defences
Authors: Xu Qilong , McShan Kristy , Liang Fang Ting 
Published: April 2008

SummaryTo initiate infection, a microbial pathogen must be able to evade innate immunity. Here we show that the Lyme disease spirochete Borrelia burgdorferi depends on its surface lipoproteins for protection against innate defences. The deficiency for OspC, an abundantly expressed surface lipoprotein during early infection, led to quick clearance of B. burgdorferi after inoculation into the skin of SCID mice. Increasing expression of any of the four randomly chosen surface lipoproteins, OspA, OspE, VlsE or DbpA, fully protected the ospC mutant from elimination from the skin tissue of SCID mice; moreover, increased OspA, OspE or VlsE expression allowed the mutant to cause disseminated infection and restored the ability to effectively colonize both joint and skin tissues, albeit the dissemination process was much slower than that of the mutant restored with OspC expression. When the ospC mutant was modified to express OspA under control of the ospC regulatory elements, it registered only a slight increase in the 50% infectious dose than the control in SCID mice but a dramatic increase in immunocompetent mice. Taken together, the study demonstrated that the surface lipoproteins provide B. burgdorferi with an essential protective function against host innate elimination.
Degree of rural isolation and birth outcomes
Authors: Luo Zhong‐Cheng , Wilkins Russell 
Published: April 2008

SummaryLittle is known about how birth outcomes vary in rural areas by degree of rural isolation. We conducted a retrospective cohort study of all births in Quebec, 1991–2000 to assess birth outcomes by the degree of rural isolation according to metropolitan influence as measured by work force commuting flows between rural and urban areas. Compared with urban areas, crude risks of preterm birth, small‐for‐gestational age birth, stillbirth, neonatal death and postneonatal death were similar in rural areas with strong metropolitan influence, but were significantly higher for preterm birth, stillbirth and postneonatal death in rural areas with weak or no metropolitan influence, and for neonatal death in rural areas with no metropolitan influence. Adjustment for maternal characteristics (age, mother tongue, education, marital status, parity, plurality and infant sex) attenuated the associations. The adjusted odds ratios [95% confidence intervals] were 1.36 [1.12, 1.64] for stillbirth in rural areas with weak metropolitan influence, 1.63 [1.14, 2.32] for neonatal death in rural areas with no metropolitan influence, 1.78 [1.21, 2.63] and 1.37 [1.07, 1.75] for postneonatal death in rural areas with weak and no metropolitan influence, respectively. Much higher neonatal death rates were observed for preterm or low‐birthweight babies in rural areas with no metropolitan influence, suggesting inadequate access to optimal neonatal care. We conclude that birth outcomes in rural areas differ according to the degree of rural isolation. Fetuses and infants of mothers from rural areas with weak or no metropolitan influence are particularly vulnerable to the risks of death during the perinatal and postnatal periods.
The definition and diagnosis of asthma
Authors: Sears M. R. , Sears Professor Malcolm R 
Published: April 2008

SummaryAsthma defies precise definition, despite several carefully worded statements. Perhaps the most concise and useful description of asthma is “variable airflow obstruction”. The diagnosis is made by recognition of a patterns of one or more characteristic symptoms including wheeze, cough, chest tightness and dyspnoea, and is best confirmed by evidence of variable or reversible airflow obstruction accompanying symptoms.
Role and contribution of viral respiratory infections to asthma
Authors: Busse William W. 
Published: April 2008

SummaryFrom the above observations, it is apparent that many respiratory viruses causes a change in airway function such that bronchial obstruction is more likely to occur in patients with asthma. Furthermore, there is also evidence that viruses act through a number of pathways to enhance the likelihood of an inflammatory response. Subsequent observations must focus on the ability of viruses to stimulate cytokine production, which could then upregulate the allergic airway inflammatory response. With the unfolding of such observations, it is highly likely that greater insights into this major provoking factor in asthma will become more apparent as well as clearer insight into mechanisms of asthma.
Morphological and Molecular Characterization of Fusarium solani Isolates
Authors: Zaccardelli M. , Vitale S. , Luongo L. , Merighi M. , Corazza L. 
Published: April 2008

Abstract Fusarium solani is a species complex (FSSC) containing isolates that cause diseases in important crops such as root and fruit rot of Cucurbita spp., root and stem rot of pea, sudden death syndrome of soybean, foot rot of bean and dry rot of potato tubers during storage. Based on host range tests, F. solani were subdivided into different formae specialis (f. sp.) and varieties, while DNA sequences of 28S rDNA, internally transcribed spacers (ITS) rDNA and elongation factor (EF‐1α) distinguished the ‘F. solani complex’ in 50 subspecific lineages. In this study we characterized, by cultural, morphological and molecular criteria, 34 isolates of F. solani obtained from potato, other crops and soil. The 34 isolates in the FSSC showed wide variability for their cultural, morphological and molecular traits. The wide variability observed with amplified fragment‐length polymorphism (AFLP) and mini‐microsatellite analyses is in agreement with the polymorphism observed, in a previous study, within FSSC. Nine of 34 isolates in the FSSC, classified as F. solani var. coeruleum, were morphologically distinguishable from the other F. solani isolates but they were distributed in different clusters; moreover, the nine isolates showed instability of the coeruleum pigmentation of the colonies, supporting the ambiguity of the taxa of this variety of F. solani. Using sequence data from ITS plus 5.8S rDNA region, the isolates were classified into different clades. In particular eight isolates were classified into a well‐supported clade including F. solani f. sp. pisi, nine into a clade including only isolates of F. solani f. sp. radicicola and four into a clade including F. solani f. sp. cucurbitae, but this classification could not be used if is not in agreement with host specificity. Two of the nine F. solani var. coeruleum isolates were phylogenetically distinct from all the other FSSC strains.
Confirmed case of feline mycetoma due to Microsporum canis
Authors: Kano Rui , Edamura Kazuya , Yumikura Hisayoshi , Maruyama Haruhiko , Asano Kazuyuki , Tanaka Shigeo , Hasegawa Atsuhiko 
Published: April 2008

SummaryThe first case of feline true mycetoma because of a dermatophyte has been reported in this manuscript, although pseudomycetoma has been described in dogs and cats. The patient was a 9‐year‐old castrated male Persian cat weighing 4.2 kg with subcutaneous nodules on the dorsal trunk. Physical examination revealed two subcutaneous nodules (2.5 × 5.0 cm and 3.5 × 5.0 cm in size) that drained purulent exudates with cement‐like substances containing yellowish granules. The impression smear of the yellowish granules demonstrated by PAS staining that they were masses of fungal septated hyphae (3–4 μm of width). From the nodular inflammation with fibrosis, fistulae draining from deep tissue and many grains containing abundant hyphal filaments, the case was diagnosed as mycetoma, complying with the definitive criteria of mycetoma. The etiologic fungus was molecularly as well as morphologically identified as Microsporum canis.
Treatment of dermatophyte onychomycosis with three pulses of terbinafine (500 mg day−1 for a week)
Authors: Takahata Y. , Hiruma M. , Shiraki Y. , Tokuhisa Y. , Sugita T. , Muto M. 
Published: April 2008

SummaryWe assessed the safety and efficacy of pulse therapy with terbinafine tablets in 55 patients with dermatophytic onychomycosis. One pulse consisted of oral terbinafine tablets (500 mg day−1) given for 1 week usually followed by a 3‐week interval. This regimen was repeated twice. Topical 1% terbinafine cream was applied daily. Efficacy was assessed based on both clinical and mycological examinations 1 year after treatment initiation. We observed a complete cure in 41 patients (74.5%), marked improved in three patients (5.6%), slight improvement in three patients (5.6%) and drop out in six patients (10.7%). Two patients (3.6%) discontinued terbinafine because of gastrointestinal disturbance (one patient) and drug‐induced eruption (one patient). No patient had abnormal laboratory findings, including liver function tests. In summary, a regimen of three pulses of terbinafine therapy given daily for 1 week in combination with topical application of terbinafine cream appears to be safe and effective in treating dermatophytic onychomycosis and offers advantages in convenience and cost‐effectiveness compared with continuous dosing.
Senescence rates are determined by ranking on the fast–slow life‐history continuum
Authors: Jones Owen R. , Gaillard Jean‐Michel , Tuljapurkar Shripad , Alho Jussi S. , Armitage Kenneth B. , Becker Peter H. , Bize Pierre , Brommer Jon , Charmantier Anne , Charpentier Marie , Clutton‐Brock Tim , Dobson F. Stephen , Festa‐Bianchet Marco , Gustafsson Lars , Jensen Henrik , Jones Carl G. , Lillandt Bo‐Göran , McCleery Robin , Merilä Juha , Neuhaus Peter , Nicoll Malcolm A. C. , Norris Ken , Oli Madan K. , Pemberton Josephine , Pietiäinen Hannu , Ringsby Thor Harald , Roulin Alexandre , Saether Bernt‐Erik , Setchell Joanna M. , Sheldon Ben C. , Thompson Paul M. , Weimerskirch Henri , Jean Wickings E. , Coulson Tim 
Published: April 2008

AbstractComparative analyses of survival senescence by using life tables have identified generalizations including the observation that mammals senesce faster than similar‐sized birds. These generalizations have been challenged because of limitations of life‐table approaches and the growing appreciation that senescence is more than an increasing probability of death. Without using life tables, we examine senescence rates in annual individual fitness using 20 individual‐based data sets of terrestrial vertebrates with contrasting life histories and body size. We find that senescence is widespread in the wild and equally likely to occur in survival and reproduction. Additionally, mammals senesce faster than birds because they have a faster life history for a given body size. By allowing us to disentangle the effects of two major fitness components our methods allow an assessment of the robustness of the prevalent life‐table approach. Focusing on one aspect of life history – survival or recruitment – can provide reliable information on overall senescence.
A landscape theory for food web architecture
Authors: Rooney Neil , McCann Kevin S. , Moore John C. 
Published: April 2008

AbstractEcologists have long searched for structures and processes that impart stability in nature. In particular, food web ecology has held promise in tackling this issue. Empirical patterns in food webs have consistently shown that the distributions of species and interactions in nature are more likely to be stable than randomly constructed systems with the same number of species and interactions. Food web ecology still faces two fundamental challenges, however. First, the quantity and quality of food web data required to document both the species richness and the interaction strengths among all species within food webs is largely prohibitive. Second, where food webs have been well documented, spatial and temporal variation in food web structure has been ignored. Conversely, research that has addressed spatial and temporal variation in ecosystems has generally ignored the full complexity of food web architecture. Here, we incorporate empirical patterns, largely from macroecology and behavioural ecology, into a spatially implicit food web structure to construct a simple landscape theory of food web architecture. Such an approach both captures important architectural features of food webs and allows for an exploration of food web structure across a range of spatial scales. Finally, we demonstrated that food webs are hierarchically organized along the spatial and temporal niche axes of species and their utilization of food resources in ways that stabilize ecosystems.