bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects ofHelicoverpa armigera(Noctuidae, Lepidoptera) host stages on some developmental parameters of the uniparental endoparasitoidMeteorus pulchricornis (Braconidae, Hymenoptera)
Authors: Ya-hui Liu , Bao-ping Li 
Published: December 2007

AbstractA single choice test was performed to examine developmental strategies in the uniparental endoparasitoidMeteorus pulchricornisand its host, the cotton bollwormHelicoverpa armigera. The results support the dome-shaped model in which the fitness functions are ‘dome-shaped’ relative to size (and age) of host at parasitism. Older and, hence, larger host larvae were simply not better hosts for the developing parasitoids. Although parasitoid size (measured as cocoon weight and adult hind tibia length) was positively correlated with host instars at parasitism, parasitoids developing in larger hosts (L5and L6) suffered much higher mortality than conspecifics developing in smaller hosts (L2–L4). Furthermore, egg-to-adult development time inM. pulchricorniswas significantly longer in older host larvae (L4–L6) than in the younger. Performance ofM. pulchricornis, as indicated by fitness-related traits, strongly suggests that the L3host is the most suitable for survival, growth and development of the parasitoid, followed by both L2and L4hosts; whereas, L1, L5and L6are the least favourable hosts. The oviposition tendency ofM. pulchricornis, represented by parasitism level, was not perfectly consistent with the performance of the offspring; L2–L4hosts, although with the same parasitism level, had offspring parasitoids with differences in fitness-related performance. Larval development inHelicoverpa armigerawas usually suspended, but occasionally advanced, in the final instar.
A radar study of emigratory flight and layer formation by insects at dawn over southern Britain
Authors: Reynolds D.R. , Smith A.D. , Chapman J.W. 
Published: December 2007

AbstractRadar observations have consistently shown that high-altitude migratory flight in insects generally occurs after mass take-off at dusk or after take-off over a more extended period during the day (in association with the growth of atmospheric convection). In this paper, we focus on a less-studied third category of emigration – the ‘dawn take-off’ – as recorded by insect-monitoring radars during the summer months in southern England. In particular, we describe occasions when dawn emigrants formed notable layer concentrations centred at altitudes ranging fromca. 240 m to 700 m above ground, very probably due to the insects responding to local temperature maxima in the atmosphere, such as the tops of inversions. After persisting for several hours through the early morning, the layers eventually merged into the insect activity building up later in the morning (from 06.00–08.00 h onwards) in conjunction with the development of daytime convection. The species forming the dawn layers have not been positively identified, but their masses lay predominantly in the 16–32 mg range, and they evidently formed a fauna quite distinct from that in flight during the previous night. The displacement and common orientation (mutual alignment) characteristics of the migrants are described.
Spatial and temporal patterns of carabid activity-density in cereals do not explain levels of predation on weed seeds
Authors: Saska P. , van der Werf W. , de Vries E. , Westerman P.R. 
Published: December 2007

AbstractSeed predation is an important component of seed mortality of weeds in agro-ecosystems, but the agronomic use and management of this natural weed suppression is hampered by a lack of insight in the underlying ecological processes. In this paper, we investigate whether and how spatial and temporal variation in activity-density of granivorous ground beetles (Coleoptera: Carabidae) results in a corresponding pattern of seed predation. Activity-density of carabids was measured by using pitfall traps in two organic winter wheat fields from March to July 2004. Predation of seeds (Capsella bursa-pastoris,Lamium amplexicaule,Poa annuaandStellaria media) was assessed using seed cards at the same sites and times. As measured by pitfall traps, carabids were the dominant group of insects that had access to the seed cards. In the field, predation of the four different species of seed was in the order:C. bursa-pastoris>P. annua>S. media>L. amplexicaule; and this order of preference was confirmed in the laboratory using the dominant species of carabid. On average, seed predation was higher in the field interior compared to the edge, whereas catches of carabids were highest near the edge. Weeks with elevated seed predation did not concur with high activity-density of carabids. Thus, patterns of spatial and temporal variation in seed predation were not matched by similar patterns in the abundance of granivorous carabid beetles. The lack of correspondence is ascribed to effects of confounding factors, such as weather, the background density of seeds, the composition of the carabid community, and the phenology and physiological state of the beetles. Our results show that differences in seed loss among weed species may be predicted from laboratory trials on preference. However, predator activity-density, as measured in pitfall traps, is an insufficient predictor of seed predation over time and space within a field.
Hearing a voice in the noise: auditory hallucinations and speech perception
Authors: Vercammen A. , de Haan E. H. F. , Aleman A. 
Published: December 2007

BackgroundIt has recently been suggested that auditory hallucinations are the result of a criterion shift when deciding whether or not a meaningful signal has emerged. The approach proposes that a liberal criterion may result in increased false-positive identifications, without additional perceptual deficit. To test this hypothesis, we devised a speech discrimination task and used signal detection theory (SDT) to investigate the underlying cognitive mechanisms.MethodSchizophrenia patients with and without auditory hallucinations and a healthy control group completed a speech discrimination task. They had to decide whether a particular spoken word was identical to a previously presented speech stimulus, embedded in noise. SDT was used on the accuracy data to calculate a measure of perceptual sensitivity (Az) and a measure of response bias (β). Thresholds for the perception of simple tones were determined.ResultsCompared to healthy controls, perceptual thresholds were higher and perceptual sensitivity in the speech task was lower in both patient groups. However, hallucinating patients showed increased sensitivity to speech stimuli compared to non-hallucinating patients. In addition, we found some evidence of a positive response bias in hallucinating patients, indicating a tendency to readily accept that a certain stimulus had been presented.ConclusionsWithin the context of schizophrenia, patients with auditory hallucinations show enhanced sensitivity to speech stimuli, combined with a liberal criterion for deciding that a perceived event is an actual stimulus.
Examining rhythmic and metric practices in Led Zeppelin’s musical style
Authors: BRACKETT JOHN 
Published: December 2007

AbstractIn this essay, I examine how aspects of rhythm and metre play a fundamental role in shaping and defining Led Zeppelin’s musical style. At the same time, I will show how Led Zeppelin was able to modify, manipulate, and develop pre-existing musical models and forms through various rhythmic and metric strategies. Comparative analyses will be used in an effort to show how Led Zeppelin’s flexible conception of rhythm and metre enabled the band to put their own stylistic ‘stamp’ on (i) specific musical genres (‘The Crunge’ and the song’s relation to James Brown-style funk), (ii) their riff constructions (‘Black Dog’ in relation to Fleetwood Mac’s ‘Oh Well’), and (iii) their cover versions (‘Dazed and Confused’). Drawing upon my analytical points, I re-visit the complex issues that persist regarding the possibility that Led Zeppelin even has an ‘original’ or ‘unique’ style given their often overt reliance upon earlier musical models and forms. Therefore, in my conclusion, I argue that the development of any artist or group’s individual style necessarily involves the ability to assimilate and transform pre-existing musical features – features such as rhythm and metre – in novel ways and where issues relating to musical style intersect with influence.
2·5×6 metres of space: Japanese music coffeehouses and experimental practices of listening
Authors: NOVAK DAVID 
Published: December 2007

AbstractThis article describes a specific history of technological mediation in the circulation of popular music by examining local practices of listening to recordings in Japanese kissaten (often shortened to kissa and meaning, loosely, ‘coffeehouse’). In postwar music kissaten, Japanese listeners were socialised to recordings of foreign music through new modes of hyper-attentive listening. While jazz kissa (though famous as crucibles for radical pro-democracy politics and the explosion of modern urban cool in post-war Japanese cities) encouraged local listeners to develop musical appreciation through the stylistic classification of distant recorded sources, later experimental music kissa helped forge unique local performance scenes by disturbing received modes of generic classification in favour of ‘Noise’. I recount the emergence of a genre called ‘Noise’ in the story of a 1970s Kyoto ‘free’ kissa Drugstore, whose countercultural clientele came to represent ‘Noise’ as a new musical style in its transnational circulation during the 1990s. This ethnographic history presents the music kissa as a complicated translocal site that articulates the cultural marginality of Japanese popular music reception in an uneven global production; but which also helps to develop virtuosic experimental practices of listening through which imported recordings are recontextualised, renamed and recreated.
Ontology-based models in pervasive computing systems
Authors: YE JUAN , COYLE LORCAN , DOBSON SIMON , NIXON PADDY 
Published: December 2007

AbstractPervasive computing is by its nature open and extensible, and must integrate the information from a diverse range of sources. This leads to a problem of information exchange, so sub-systems must agree on shared representations. Ontologies potentially provide a well-founded mechanism for the representation and exchange of such structured information. A number of ontologies have been developed specifically for use in pervasive computing, none of which appears to cover adequately the space of concerns applicable to application designers. We compare and contrast the most popular ontologies, evaluating them against the system challenges generally recognized within the pervasive computing community. We identify a number of deficiencies that must be addressed in order to apply the ontological techniques successfully to next-generation pervasive systems.
Hypoxia, via stabilization of the hypoxia-inducible factor HIF-1α, is a direct and sufficient stimulus for brain-type natriuretic peptide induction
Authors: Weidemann Alexander , Klanke Bernd , Wagner Michael , Volk Tilmann , Willam Carsten , Wiesener Michael S. , Eckardt Kai-Uwe , Warnecke Christina 
Published: December 2007

BNP (brain-type natriuretic peptide) is a cardiac hormone with systemic haemodynamic effects as well as local cytoprotective and antiproliferative properties. It is induced under a variety of pathophysiological conditions, including decompensated heart failure and myocardial infarction. Since regional hypoxia is a potential common denominator of increased wall stretch and myocardial hypoperfusion, we investigated the direct effects of hypoxia on BNP expression, and the role of the HIF (hypoxia-inducible transcription factor) in BNP regulation. Using an RNase protection assay we found a strong hypoxic induction of BNP mRNA expression in different cell lines and in cultured adult rat cardiomyocytes. Systemic hypoxia and exposure to 0.1% CO induced BNP expression in the rodent myocardium in vivo, although this was at a lower amplitude. BNP promoter-driven luciferase expression increased 10-fold after hypoxic stimulation in transient transfections. Inactivation of four putative HREs (hypoxia-response elements) in the promoter by site-directed mutagenesis revealed that the HRE at −466 nt was responsible for hypoxic promoter activation. A functional CACAG motif was identified upstream of this HRE. The HIF-1 complex bound specifically and inducibly only to the HRE at −466 nt, as shown by EMSA (electrophoretic mobility-shift assay) and ChIP (chromatin immunoprecipitation). siRNA (small interfering RNA)-mediated knockdown of HIF-1α, but not HIF-2α, interfered with hypoxic BNP mRNA induction and BNP promoter activation, confirming that BNP is a specific HIF-1α target gene. In conclusion, BNP appears to be part of the protective program steered by HIF-1 in response to oxygen deprivation. Induction of BNP may therefore contribute to the potential benefits of pharmacological HIF inducers in the treatment of ischaemic heart disease and heart failure.
Diacylglycerol kinases: at the hub of cell signalling
Authors: Mérida Isabel , Ávila-Flores Antonia , Merino Ernesto 
Published: December 2007

DGKs (diacylglycerol kinases) are members of a unique and conserved family of intracellular lipid kinases that phosphorylate DAG (diacylglycerol), catalysing its conversion into PA (phosphatidic acid). This reaction leads to attenuation of DAG levels in the cell membrane, regulating a host of intracellular signalling proteins that have evolved the ability to bind this lipid. The product of the DGK reaction, PA, is also linked to the regulation of diverse functions, including cell growth, membrane trafficking, differentiation and migration. In multicellular eukaryotes, DGKs provide a link between lipid metabolism and signalling. Genetic experiments in Caenorhabditis elegans, Drosophila melanogaster and mice have started to unveil the role of members of this protein family as modulators of receptor-dependent responses in processes such as synaptic transmission and photoreceptor transduction, as well as acquired and innate immune responses. Recent discoveries provide new insights into the complex mechanisms controlling DGK activation and their participation in receptor-regulated processes. After more than 50 years of intense research, the DGK pathway emerges as a key player in the regulation of cell responses, offering new possibilities of therapeutic intervention in human pathologies, including cancer, heart disease, diabetes, brain afflictions and immune dysfunctions.
Annexins sense changes in intracellular pH during hypoxia
Authors: Monastyrskaya Katia , Tschumi Fabian , Babiychuk Eduard B. , Stroka Deborah , Draeger Annette 
Published: December 2007

The pHi (intracellular pH) is an important physiological parameter which is altered during hypoxia and ischaemia, pathological conditions accompanied by a dramatic decrease in pHi. Sensors of pHi include ion transport systems which control intracellular Ca2+ gradients and link changes in pHi to functions as diverse as proliferation and apoptosis. The annexins are a protein family characterized by Ca2+-dependent interactions with cellular membranes. Additionally, in vitro evidence points to the existence of pH-dependent, Ca2+-independent membrane association of several annexins. We show that hypoxia promotes the interaction of the recombinant annexin A2–S100A10 (p11) and annexin A6 with the plasma membrane. We have investigated in vivo the influence of the pHi on the membrane association of human annexins A1, A2, A4, A5 and A6 tagged with fluorescent proteins, and characterized this interaction for endogenous annexins present in smooth muscle and HEK (human embryonic kidney)-293 cells biochemically and by immunofluorescence microscopy. Our results show that annexin A6 and the heterotetramer A2–S100A10 (but not annexins A1, A4 and A5) interact independently of Ca2+ with the plasma membrane at pH 6.2 and 6.6. The dimerization of annexin A2 within the annexin A2–S100A10 complex is essential for the pH-dependent membrane interaction at this pH range. The pH-induced membrane binding of annexins A6 and A2–S100A10 might have consequences for their functions as membrane organizers and channel modulators.
Can rodent models of diabetic kidney disease clarify the significance of early hyperfiltration?: recognizing clinical and experimental uncertainties
Authors: Levine David Z. 
Published: December 2007

In the past, hyperfiltration and increased glomerular capillary pressure have been identified as important determinants of the development of DN (diabetic nephropathy). Recently, some basic research and clinical reviews on DN have omitted identifying hyperfiltration as an important risk factor. At the same time, different rodent models of DN have been described without and with documented hyperfiltration. In the present review, the importance of hyperfiltration is reassessed, reviewing key clinical and research studies, including the first single nephron studies in a mouse model of DN. From clinical studies of Type 1 and Type 2 diabetes mellitus, it is clear that many patients do not have early hyperfiltration and, even when present, its contribution to subsequent DN remains uncertain. Key mechanisms underlying hyperfiltration in rodent models are reviewed. Findings on intrarenal NO metabolism and the control of single-nephron GFR (glomerular filtration rate) in rodent models of DN are also presented. Characterization of valid experimental models of DN should include a careful delineation of the absence or presence of early hyperfiltration, with special efforts made to establish the specific role hyperfiltration may play in the emergence of DN.
Heightened α1A-adrenergic receptor activity suppresses ischaemia/reperfusion-induced Ins(1,4,5)P3 generation in the mouse heart: a comparison with ischaemic preconditioning
Authors: Amirahmadi Fatemeh , Turnbull Lynne , Du Xiao-Jun , Graham Robert M. , Woodcock Elizabeth A. 
Published: December 2007

Reperfusion of ischaemic rat or mouse hearts causes NE [noradrenaline (‘norepinephrine’)] release, stimulation of α1-ARs (α1-adrenergic receptors), PLC (phospholipase C) activation, Ins(1,4,5)P3 generation and the development of arrhythmias. In the present study, we examined the effect of increased α1A-AR drive on these responses. In hearts from non-transgenic mice (α1A-WT), Ins(1,4,5)P3 generation was observed after 2 min of reperfusion following 30 min of zero-flow ischaemia. No Ins(1,4,5)P3 response was observed in hearts from transgenic mice with 66-fold overexpression of α1A-AR (α1A-TG). This was despite the fact that α1A-TG hearts had 8–10-fold higher PLC responses to NE than α1A-WT under normoxic conditions. The immediate phospholipid precursor of Ins(1,4,5)P3, PtdIns(4,5)P2, responded to ischaemia and reperfusion similarly in α1A-WT and α1A-TG mice. Thus the lack of Ins(1,4,5)P3 generation in α1A-TG mice is not caused by limited availability of PtdIns(4,5)P2. Overall, α1-AR-mediated PLC activity was markedly enhanced in α1A-WT mice under reperfusion conditions, but responses in α1A-TG mice were not significantly different in normoxia and post-ischaemic reperfusion. Ischaemic preconditioning prevented Ins(1,4,5)P3 generation after 30 min of ischaemic insult in α1A-WT mice. However, the precursor lipid PtdIns(4,5)P2 was also reduced by preconditioning, whereas heightened α1A-AR activity did not influence PtdIns(4,5)P2 responses in reperfusion. Thus preconditioning and α1A-AR overexpression have different effects on early signalling responses, even though both prevented Ins(1,4,5)P3 generation. These studies demonstrate a selective inhibitory action of heightened α1A-AR activity on immediate post-receptor signalling responses in early post-ischaemic reperfusion.
Does compensatory nitric oxide and angiotensin II receptor activity reduce arterial stiffness in early-stage insulin resistance?
Authors: Woodman Richard J. 
Published: December 2007

Increased arterial stiffness is influenced by both functional and structural properties of the vessel wall, including changes in content of smooth muscle, elastin and collagen, reduced endothelial production of NO and increased release of endothelin-1 or AngII (angiotensin II). The RAS (renin–angiotensin) system is likely to be central to increases in arterial stiffness, since the changes in arterial structure observed with enhanced AngII activity are similar to the same pathophysiological changes that contribute to arterial stiffness. The role of AT1R and AT2R (AngII type 1 and type 2 receptors respectively) in the development of arterial stiffening, particularly in the early stages of insulin resistance, is however unclear. In this issue of Clinical Science, Brillante and co-workers have observed that in insulin-resistant subjects exhibiting reduced arterial stiffness, wave reflection from small-to-medium-sized, but not large, arteries was increased following separate intravenous infusions of AngII, the selective AT2R inhibitor PD123319 and the NO inhibitor L-NMMA (NG-monomethyl-L-arginine) in comparison with normal healthy age- and sex-matched controls. These increases probably reflect increased AT1R and AT2R expression/activity in addition to up-regulation of basal NO release in the small-to-medium-sized arteries. These changes may be compensatory mechanisms related to early vascular damage and may have clinical implications for treatment in hypertensive patients with evidence of the metabolic syndrome.
Modulation of Proteasome Activity by Vitamin E in THP‐1 Monocytes
Authors: Munteanu Adelina , Ricciarelli Roberta , Massone Sara , Zingg Jean‐Marc 
Published: December 2007

AbstractIn THP‐1 monocytes, cellular proteasome inhibition by ritonavir or ALLN is associated with increased production of oxidative stress. Both compounds produced comparable amounts of oxidative stress; however, normalization by α‐tocopherol occurred solely after inhibition by ritonavir, and not by ALLN. Similar to that, α‐tocopherol could normalize the reduced formation of 3‐nitrotyrosine‐modified proteins only after ritonavir treatment. In the absence of any proteasome inhibitor, intrinsic cellular proteasome activity was not modulated by α‐, β‐, and γ‐tocopherols; however, δ‐tocopherol, α‐tocotrienol, and α‐tocopheryl phosphate could significantly inhibit cellular proteasome activity and increased the level of p27Kip1 and p53. Since oxidative stress was reduced by α‐tocopherol only after proteasome inhibition by ritonavir and not by ALLN, it is concluded that, in this experimental system, α‐tocopherol does not act as an antioxidant but interferes with the inhibitory effect of ritonavir.
Tipping the Scales ‐ Specifier Proteins in Glucosinolate Hydrolysis
Authors: Wittstock Ute , Burow Meike 
Published: December 2007

AbstractGlucosinolates are a group of secondary plant metabolites found in the Brassicales order that are beneficial components of our diet, determine the flavor of a number of vegetables and spices and have been implicated in pest management strategies. These properties, most of the biological activities and the pungent odor and taste associated with glucosinolate‐containing plants are due to the products formed from glucosinolates by their hydrolytic enzymes, myrosinases, upon tissue disruption. Specifier proteins impact the outcome of glucosinolate hydrolysis without having hydrolytic activity on glucosinolates themselves. In the presence of specifier proteins, glucosinolate hydrolysis results in nitriles, epithionitriles and organic thiocyanates whose biological functions are currently unknown. In contrast, isothiocyanates formed in the absence of specifier proteins have been demonstrated to possess a variety of biological activities and are thought to protect plants from herbivore and pathogen attack. This review discusses the current knowledge on plant and insect specifier proteins with special emphasis on their biochemical properties and possible mechanisms of action.