bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Glucose Control and Improvement of Insulin Resistance on Microvascular Blood Flow and Endothelial Function in Patients with Diabetes Mellitus Type 2
Authors: FORST THOMAS , LÜBBEN GEORG , HOHBERG CLOTHILDE , KANN PETER , SACHARA CHRISTIAN , GOTTSCHALL VOLKER , FRIEDRICH CHRISTIANE , ROßKOPF REINER , PFÜTZNER ANDREAS
Published: December 2005

Objective: The study was performed to investigate the effect of improving metabolic control with pioglitazone in comparison to glimepiride on microvascular function in patients with diabetes mellitus type 2.

Methods: A total of 179 patients were recruited and randomly assigned to one treatment group. Metabolic control (HbA1c), insulin resistance (HOMA index), and microvascular function (laser Doppler fluxmetry) were observed at baseline and after 3 and 6 months.

Results: HbA1c improved in both treatment arms (pioglitazone: 7.52 ± 0.85% to 6.71 ± 0.89%, p < .0001; glimepiride: 7.44 ± 0.89% to 6.83 ± 0.85%, p < .0001). Insulin‐resistance decreased significantly in the pioglitazone group (6.15 ± 4.05 to 3.85 ± 1.92, p < .0001) and remained unchanged in the glimepiride group. The microvascular response to heat significantly improved in both treatment groups (pioglitazone 48.5 [15.2; 91.8] to 88.8 [57.6; 124.1] arbitrary units [AU], p < .0001; glimepiride 53.7 [14.1; 91.9] to 87.9 [52.9, 131.0] AU, p < .0001, median [lower and upper quartile]). Endothelial function as measured with the acetylcholine response improved in the pioglitazone group (38.5 [22.2; 68.0] to 60.2 [36.9; 82.8], p = .0427) and remained unchanged in the glimepiride group.

Conclusions: Improving metabolic control has beneficial effects in microvascular function in type 2 diabetic patients. Treatment of type 2 diabetic patients with pioglitazone exerts additional effects on endothelial function beyond metabolic control.
Ischemia–Reperfusion Impairs Ascending Vasodilation in Feed Arteries of Hamster Skeletal Muscle
Authors: DE WITH MIRIAM C. J. , HAUG SARA J. , BRIGITTE VAN DER HEIJDEN E. P. A. , SEGAL STEVEN S.
Published: December 2005

Objective: Vasodilation originating within the microcirculation ascends into proximal feed arteries during muscle contraction to attain peak levels of muscle blood flow. Ascending vasodilation (AVD) requires an intact endothelium, as does conducted vasodilation in response to acetylcholine (ACh). Whereas ischemia–reperfusion (I‐R) can affect endothelial cell function, the effect of I‐R on AVD is unknown. The authors tested the hypothesis that I‐R (1h–1h) would impair AVD.

Methods: Using the retractor muscle of anesthetized hamsters, contractions were evoked using field stimulation (200 ms at 40 Hz every 2 s for 1 min) and ACh was delivered using microiontophoresis (1 μm tip, 500–4000 ms pulse at 800 nA). Feed artery responses were monitored 500–1500 μm upstream.

Results: Neither resting (51 ± 4 μm) nor maximal diameter (81 ± 5 μm; 10 μm sodium nitroprusside) following I‐R (n = 8) were different from time‐matched controls (n = 10). With peak active tension of 23 ± 4 mN · mm−2, control AVD was 26 ± 2 μm. Following I‐R, active tension fell by 48% (p < .05) and AVD by 57% (p < .05). Stimulation at 70 Hz restored active tension but AVD remained depressed by nearly half (p < .05), as did local and conducted responses to ACh. Nevertheless, control responses to 500 ms ACh were restored by increasing stimulus duration to 4000 ms.

Conclusions: Ischemia–reperfusion impairs the initiation of feed artery dilation with muscle contraction and with ACh while conduction along the vessel wall is preserved. Respective components of endothelial cell signaling events may differ in their susceptibility to I‐R.
Interleukin‐1β Reduces Transcellular Monocyte Diapedesis and Compromises Endothelial Adherens Junction Integrity
Authors: FERREIRA ALEXANDER M. , MCNEIL CEARA J. , STALLAERT KAREN M. , ROGERS KEM A. , SANDIG MARTIN
Published: December 2005

Objective: Diapedesis occurs through endothelial cell–cell junctions (paracellular) or through individual endothelial cells without disrupting junctions (transcellular). While in vitro studies have provided considerable insight into mechanisms controlling paracellular diapedesis, little is known about what regulates transcellular diapedesis. The authors investigated whether transcellular diapedesis is susceptible to IL‐1β exposure of the endothelium.

Methods: Laser scanning confocal microscopy and biochemical analysis were used to determine the effect of IL‐1β pretreatment of the endothelium on adherens junctional morphology and monocyte transcellular diapedesis in cocultures of human peripheral blood monocytes and coronary artery endothelial cells.

Results: IL‐1β pretreatment caused a 40% decrease in the number of migrating monocytes that used a transcellular route of diapedesis, and resulted in elongate endothelial cell morphology, a reorganization of the F‐actin cytoskeleton, and a significant decrease in transendothelial electrical resistance. In IL‐1β treated monolayers, VE‐cadherin and its associated catenins were distributed in a punctate pattern in comparison to the lacy pattern seen in control monolayers. Coimmunoprecipitation of VE‐cadherin molecular assemblies revealed that IL‐1β‐mediated changes in distribution were associated with a decrease in the presence of cadherin/catenin complexes in the detergent insoluble fraction.

Conclusions: IL‐1β‐induced rearrangement of interendothelial adherens junctions facilitates paracellular diapedesis at the expense of transcellular diapedesis.
Intracellular pH Modulates Taste Receptor Cell Volume and the Phasic Part of the Chorda Tympani Response to Acids
Authors: Lyall Vijay , Pasley Hampton , Phan Tam-Hao T. , Mummalaneni Shobha , Heck Gerard L. , Vinnikova Anna K. , DeSimone John A.
Published: December 2005

The relationship between cell volume and the neural response to acidic stimuli was investigated by simultaneous measurements of intracellular pH (pHi) and cell volume in polarized fungiform taste receptor cells (TRCs) using 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF) in vitro and by rat chorda tympani (CT) nerve recordings in vivo. CT responses to HCl and CO2 were recorded in the presence of 1 M mannitol and specific probes for filamentous (F) actin (phalloidin) and monomeric (G) actin (cytochalasin B) under lingual voltage clamp. Acidic stimuli reversibly decrease TRC pHi and cell volume. In isolated TRCs F-actin and G-actin were labeled with rhodamine phalloidin and bovine pancreatic deoxyribonuclease-1 conjugated with Alexa Fluor 488, respectively. A decrease in pHi shifted the equilibrium from F-actin to G-actin. Treatment with phalloidin or cytochalasin B attenuated the magnitude of the pHi-induced decrease in TRC volume. The phasic part of the CT response to HCl or CO2 was significantly decreased by preshrinking TRCs with hypertonic mannitol and lingual application of 1.2 mM phalloidin or 20 μM cytochalasin B with no effect on the tonic part of the CT response. In TRCs first treated with cytochalasin B, the decrease in the magnitude of the phasic response to acidic stimuli was reversed by phalloidin treatment. The pHi-induced decrease in TRC volume induced a flufenamic acid–sensitive nonselective basolateral cation conductance. Channel activity was enhanced at positive lingual clamp voltages. Lingual application of flufenamic acid decreased the magnitude of the phasic part of the CT response to HCl and CO2. Flufenamic acid and hypertonic mannitol were additive in inhibiting the phasic response. We conclude that a decrease in pHi induces TRC shrinkage through its effect on the actin cytoskeleton and activates a flufenamic acid–sensitive basolateral cation conductance that is involved in eliciting the phasic part of the CT response to acidic stimuli.
Regulation of Connexin Hemichannels by Monovalent Cations
Authors: Srinivas Miduturu , Calderon D. Paola , Kronengold Jack , Verselis Vytas K.
Published: December 2005

Opening of connexin hemichannels in the plasma membrane is highly regulated. Generally, depolarization and reduced extracellular Ca2+ promote hemichannel opening. Here we show that hemichannels formed of Cx50, a principal lens connexin, exhibit a novel form of regulation characterized by extraordinary sensitivity to extracellular monovalent cations. Replacement of extracellular Na+ with K+, while maintaining extracellular Ca2+ constant, resulted in >10-fold potentiation of Cx50 hemichannel currents, which reversed upon returning to Na+. External Cs+, Rb+, NH4+, but not Li+, choline, or TEA, exhibited a similar effect. The magnitude of potentiation of Cx50 hemichannel currents depended on the concentration of extracellular Ca2+, progressively decreasing as external Ca2+ was reduced. The primary effect of K+ appears to be a reduction in the ability of Ca2+, as well as other divalent cations, to close Cx50 hemichannels. Cx46 hemichannels exhibited a modest increase upon substituting Na+ with K+. Analyses of reciprocal chimeric hemichannels that swap NH2- and COOH-terminal halves of Cx46 and Cx50 demonstrate that the difference in regulation by monovalent ions in these connexins resides in the NH2-terminal half. Connexin hemichannels have been implicated in physiological roles, e.g., release of ATP and NAD+ and in pathological roles, e.g., cell death through loss or entry of ions and signaling molecules. Our results demonstrate a new, robust means of regulating hemichannels through a combination of extracellular monovalent and divalent cations, principally Na+, K+, and Ca2+.
The V260I Mutation in Fission Yeast α-Tubulin Atb2 Affects Microtubule Dynamics and EB1-Mal3 Localization and Activates the Bub1 Branch of the Spindle Checkpoint
Authors: Asakawa Kazuhide , Kume Kazunori , Kanai Muneyoshi , Goshima Tetsuya , Miyahara Kohji , Dhut Susheela , Tee Wee Wei , Hirata Dai , Toda Takashi
Published: January 2006

We have identified a novel temperature-sensitive mutant of fission yeast α-tubulin Atb2 (atb2-983) that contains a single amino acid substitution (V260I). Atb2-983 is incorporated into the microtubules, and their overall structures are not altered noticeably, but microtubule dynamics is compromised during interphase. atb2-983 displays a high rate of chromosome missegregation and is synthetically lethal with deletions in a subset of spindle checkpoint genes including bub1, bub3, and mph1, but not with mad1, mad2, and mad3. During early mitosis in this mutant, Bub1, but not Mad2, remains for a prolonged period in the kinetochores that are situated in proximity to one of the two SPBs (spindle pole bodies). High dosage mal3+, encoding EB1 homologue, rescues atb2-983, suggesting that Mal3 function is compromised. Consistently, Mal3 localization and binding between Mal3 and Atb2-983 are impaired significantly, and a mal3 single mutant, such as atb2-983, displays prolonged Bub1 kinetochore localization. Furthermore in atb2-983 back-and-forth centromere oscillation during prometaphase is abolished. Intriguingly, this oscillation still occurs in the mal3 mutant, indicating that there is another defect independent of Mal3. These results show that microtubule dynamics is important for coordinated execution of mitotic events, in which Mal3 plays a vital role.
Real Balance Effects and Monetary Policy
Authors: Piergallini Alessandro
Published: January 2006

This article presents a dynamic stochastic new Keynesian model with real balance effects. I find a number of results that would not appear in the traditional framework. It is shown that the real balance effect makes the so‐called Taylor principle not necessary for determinacy of rational expectations equilibrium and that “passive” monetary rules may be feasible. In addition, within a class of policy rules constrained to be a linear function of state variables, “active” interest rate rules are more likely to be optimal under commitment rather than under discretion. (JEL E52, E58)
Audiovestibular Manifestations of Sarcoidosis: A Review of the Literature
Authors: Colvin I. B.
Published: January 2006

Objective/Hypothesis: Sarcoidosis is a multisystem disease of unknown etiology. Audiovestibular involvement is rare but has been reported in a number of cases. The objective of this review is to provide an evidence‐based summary of the audiovestibular manifestations of sarcoidosis by collating the findings of these case reports.

Study Design: Retrospective review of 48 published case reports and 2 cases recently encountered in audiovestibular medicine clinics.

Methods: Case reports were identified using a key word search of Medline database. Clinical details, audiovestibular test results, and radiological findings were recorded for each patient when available.

Results: When type of hearing loss (HL) was recorded, all losses were sensorineural, with only two patients found to have an additional conductive loss. The severity of HL ranged from mild to profound. Median thresholds were moderately raised. The HL was bilateral in 75% of patients and asymmetrical in 75% of these cases. Seventy percent of HLs demonstrated some recovery. Many of the patients with recovery were treated with corticosteroids, but no statistically significant association between treatment and HL outcome was observed. Symptoms of vestibular impairment were common. Vestibular testing was performed in 24 cases and was abnormal in 23. Eighty‐one percent of patients had additional features of neurosarcoidosis. Six patients had radiological evidence of a retrocochlear lesion.

Conclusions: In taking into account the evidence from the clinical features, audiovestibular testing, radiological investigations, and postmortem findings, it is concluded that the audiovestibular manifestations of sarcoidosis are likely to be primarily a result of vestibulocochlear nerve neuropathy.
Effects of Vitamin E on Cigarette Smoke Induced Oxidative Damage in Larynx and Lung
Authors: Üneri Cüneyd , Sari Murat , Bağlam Tekin , Polat Şenol , Yüksel Meral
Published: January 2006

Objectives: Cigarette smoke (CS) contains a large variety of compounds, including many oxidants and free radicals (also known as reactive oxygen species), that are capable of initiating or promoting oxidative damage, which leads to various degenerative pulmonary and cardiovascular diseases as well as cancer. Recent studies have established a strong relationship between CS and development of reactive oxygen species (ROS). The aim of the present study was to detect ROS levels in laryngeal and lung tissues of rats by measuring luminol‐amplified chemiluminescence and to determine the changes in ROS levels in lung and laryngeal tissues induced by exposure to CS, with and without concurrent treatment with vitamin E.

Study Design: Prospective controlled animal study.

Methods: Male Sprague‐Dawley rats were divided into three groups of eight animals each. The first group of rats was exposed to cigarette smoke. The second group of rats was exposed to cigarette smoke and concurrently treated with vitamin E. The third group was used as control. Animals were killed and chemiluminescence measurements were made for laryngeal and lung tissues.

Results: Reactive oxygen species levels were significantly increased in the first group of rats compared to the levels measured in control animals. ROS levels were statistically significantly decreased in the second group as compared to the first group.

Conclusion: Our results indicate that vitamin E decreases CS induced ROS levels in laryngeal and lung tissues.
Intrathyroid Hemorrhage and Acute Upper Airway Obstruction after Fine Needle Aspiration of the Thyroid Gland
Authors: Roh Jong‐Lyel
Published: January 2006

Objectives: Although hematoma formation after fine needle aspiration (FNA) is the most commonly encountered complication, massive intrathyroid hemorrhage producing acute upper airway obstruction rarely occurs.

Study Design: Case report.

Methods: This case presented a 55‐year‐old woman with acute intrathyroid hemorrhage producing upper airway obstruction after diagnostic FNA of multiple thyroid nodules.

Results: The patient underwent endotracheal intubation and subsequent total thyroidectomy because of rapid progression of airway symptoms. During operation, the thyroid gland showed a huge, edematous, firm swelling and intrathyroidal hemorrhage with no obvious actively bleeding vessels. Microscopic examination of the resected gland revealed bilateral multiple nodular hyperplasia and massive parenchymal hemorrhage with thin‐walled, aberrantly enlarged vessels.

Conclusion: Acute intrathyroid hemorrhage causing upper airway obstruction can develop after FNA of the thyroid. Prompt and adequate interventions are needed for patients with rapid progression of acute thyroid hemorrhage.
Empiric Treatment of Laryngopharyngeal Reflux with Proton Pump Inhibitors: A Systematic Review
Authors: Karkos Petros D. , Wilson Janet A.
Published: January 2006

Objective: The objective of this study was to define the outcome of empiric treatment of suspected laryngopharyngeal reflux (LPR) symptoms with proton pump inhibitors (PPIs).

Design: The authors conducted a systematic review of the English and foreign literature. Studies that used PPIs as an empiric treatment modality for suspected LPR, whether alone or in combination with other acid suppressants and/or placebo, were included. Studies that did not include PPIs as a treatment option were excluded.

Main Outcome Measures: A lack of common outcome measures was evident in the uncontrolled studies. In the randomized, controlled trials, outcome measures included symptom questionnaires and videolaryngoscopy. Only one study used computerized voice analysis.

Results: Fourteen uncontrolled studies together with one unblinded, nonrandomized study with a control group of healthy volunteers and six double‐blind, placebo‐controlled randomized trials were identified from 1994 to 2004. Selection bias, blinding of the results, and lack of common outcome measures were some of the problems preventing a formal metaanalysis. Although uncontrolled series reported positive results, randomized, controlled trials demonstrated no statistically significant differences for changes in severity or frequency of symptoms associated with suspected reflux between PPIs and placebo.

Conclusions: Recommendations for empiric treatment of suspected LPR with PPIs, by far the most common ear, nose and throat practice in the United Kingdom, are based on poor levels of evidence from uncontrolled studies. The few randomized, controlled trials have failed to demonstrate superiority of PPIs over placebo for treatment of suspected LPR.
‘Eavesdropping’ in wild rough-toothed dolphins (
Steno bredanensis
)?
Authors: Götz Thomas , Verfuß Ursula Katharina , Schnitzler Hans-Ulrich
Published: December 2005

Several authors suggest that dolphins use information obtained by eavesdropping on echoes from sonar signals of conspecifics, but there is little evidence that this strategy is used by dolphins in the wild. Travelling rough-toothed dolphins (
Steno bredanensis
) either exhibit asynchronous movements or an extremely synchronized swimming behaviour in tight formations, which we expect to facilitate eavesdropping. Therefore, we determined, whether either one or more dolphins were echolocating in subgroups that were travelling with asynchronous and synchronized movements. Since, the number of recording sequences in which more than one animal produced sonar signals was significantly lower during synchronized travel, we conclude that the other members of a subgroup might get information on targets ahead by eavesdropping. Synchronized swimming in tight formations might be an energetic adaptation for travelling in a pelagic dolphin species that facilitates eavesdropping.
Modelling the extinction of Steller's sea cow
Authors: Turvey S.T , Risley C.L
Published: December 2005

Steller's sea cow, a giant sirenian discovered in 1741 and extinct by 1768, is one of the few megafaunal mammal species to have died out during the historical period. The species is traditionally considered to have been exterminated by ‘blitzkrieg’-style direct overharvesting for food, but it has also been proposed that its extinction resulted from a sea urchin population explosion triggered by extirpation of local sea otter populations that eliminated the shallow-water kelps on which sea cows fed. Hunting records from eighteenth century Russian expeditions to the Commander Islands, in conjunction with life-history data extrapolated from dugongs, permit modelling of sea cow extinction dynamics. Sea cows were massively and wastefully overexploited, being hunted at over seven times the sustainable limit, and suggesting that the initial Bering Island sea cow population must have been higher than suggested by previous researchers to allow the species to survive even until 1768. Environmental changes caused by sea otter declines are unlikely to have contributed to this extinction event. This indicates that megafaunal extinctions can be effected by small bands of hunters using pre-industrial technologies, and highlights the catastrophic impact of wastefulness when overexploiting resources mistakenly perceived as ‘infinite’.
Fees or refuges: which is better for the sustainable management of insect resistance to transgenicBtcorn?
Authors: Vacher Corinne , Bourguet Denis , Desquilbet Marion , Lemarié Stéphane , Ambec Stéfan , Hochberg Michael E
Published: December 2005

The evolution of resistance in insect pests will imperil the efficiency of transgenic insect-resistant crops. The currently advised strategy to delay resistance evolution is to plant non-toxic crops (refuges) in close proximity to plants engineered to express the toxic protein of the bacteriumBacillus thuringiensis(Bt). We seek answers to the question of how to induce growers to plant non-toxic crops. A first strategy, applied in the United States, is to requireBtgrowers to plant non-Btrefuges and control their compliance with requirements. We suggest that an alternative strategy is to makeBtseed more expensive by instituting a user fee, and we compare both strategies by integrating economic processes into a spatially explicit, population genetics model. Our results indicate that although both strategies may allow the sustainable management of the common pool ofBt-susceptibility alleles in pest populations, for the European corn borer (Ostrinia nubilalis) one of the most serious pests in the US corn belt, the fee strategy is less efficient than refuge requirements.
The role of model female quality in the mate choice copying behaviour of sailfin mollies
Authors: Hill Sarah E , Ryan Michael J
Published: December 2005

Female mate choice copying is a socially mediated mate choice behaviour, in which a male's attractiveness to females increases if he was previously chosen by another female as a mate. Although copying has been demonstrated in numerous species, little is known about the specific benefits it confers to copying females. Here we demonstrate that the mate choice behaviour of female sailfin mollies (
Poecilia latipinna
) is influenced by the phenotypic quality of model females with whom males are observed consorting. Test females choosing between two males of similar body length were found to significantly increase time spent with previously non-preferred males after having observed them with a relatively high-quality female. Conversely, females were found to significantly decrease time spent with previously preferred males after having observed them with a relatively low-quality female. Female mate choice copying might be maintained by selection based on the heuristic value it provides females choosing between males whose quality differences are not easily distinguishable.
Fibre slippage in cyclically perturbed fibrous assemblies
Authors: Wilkins Andy
Published: January 2006

The dynamics of fibre slippage within general non-bonded fibrous assemblies is studied in the situation where the assembly is subjected to general small cyclic loads. Two models are proposed. The first is applicable when the general cyclic loading is complemented by an occasional tugging force on one end of a fibre, which causes it to gradually withdraw from the assembly, such as might occur during the pilling of a textile. The second considers the situation in which the cyclic perturbations act around a constant background load applied to the assembly. The dynamics is reminiscent of self-organized critical behaviour. This model is applied to predict the progressive elongation of a single yarn during weaving.
Visual search for a target changing in synchrony with an auditory signal
Authors: Fujisaki Waka , Koene Ansgar , Arnold Derek , Johnston Alan , Nishida Shin'ya
Published: December 2005

We examined whether the detection of audio–visual temporal synchrony is determined by a pre-attentive parallel process, or by an attentive serial process using a visual search paradigm. We found that detection of a visual target that changed in synchrony with an auditory stimulus was gradually impaired as the number of unsynchronized visual distractors increased (experiment 1), whereas synchrony discrimination of an attended target in a pre-cued location was unaffected by the presence of distractors (experiment 2). The effect of distractors cannot be ascribed to reduced target visibility nor can the increase in false alarm rates be predicted by a noisy parallel processing model. Reaction times for target detection increased linearly with number of distractors, with the slope being about twice as steep for target-absent trials as for target-present trials (experiment 3). Similar results were obtained regardless of whether the audio–visual stimulus consisted of visual flashes synchronized with amplitude-modulated pips, or of visual rotations synchronized with frequency-modulated up–down sweeps. All of the results indicate that audio–visual perceptual synchrony is judged by a serial process and are consistent with the suggestion that audio–visual temporal synchrony is detected by a ‘mid-level’ feature matching process.
Red dominates black: agonistic signalling among head morphs in the colour polymorphic Gouldian finch
Authors: Pryke Sarah R , Griffith Simon C
Published: December 2005

Recent sexual selection studies on the evolution of bird colouration have mainly focused on signals with a high level of condition-dependent variation, with much less attention given to colour traits whose expression is genetically controlled. Here, we experimentally tested the relative importance of a genetic colour polymorphism in determining male dominance in the Gouldian finch (
Erythrura gouldiae
), a species displaying three completely discrete but naturally co-occurring genetically inherited phenotypes; yellow-, red- (carotenoid) and black-headed (melanin) morphs. First, in staged dominance contests between unfamiliar birds of different head morphs, red-headed males dominated black-headed males, both of which dominated the yellow-headed birds. Second, within morphs, the intensity and size of the strongly ultraviolet-blue collar determined the outcome of these contests, and among the red-headed males, redder males dominated less chromatic birds. Lastly, when the dominance signal of red-headed birds was experimentally destabilized (i.e. blackened or reddened), naturally red-headed morphs continued to dominate both the black-and yellow-headed morphs. Together, these results suggest that intrinsic dominance-related behavioural differences between the three colour morphs, which are likely to influence the relative fitness of each morph, contribute to the complex selective patterns maintaining these three discrete phenotypes in relatively stable frequencies in wild populations.
Ancient trans-Atlantic flight explains locust biogeography: molecular phylogenetics ofSchistocerca
Authors: Lovejoy N.R , Mullen S.P , Sword G.A , Chapman R.F , Harrison R.G
Published: December 2005

The desert locust (Schistocerca gregaria) has been an important agricultural pest at least since biblical times. Although the ecology, physiology and behaviour of this insect species have been well characterized, its biogeographical origins and evolutionary history are more obscure.Schistocerca gregariaoccurs throughout Africa, the Middle East and Western Asia, but all other species in the genusSchistocercaare found in the New World. BecauseS. gregariahas the capacity for extreme long-distance movement associated with swarming behaviour, dispersal may have played an important role in determining current distribution patterns. Some authors have argued thatS. gregariais the product of an eastward trans-Atlantic dispersal from North America to Africa; others consider it more likely that the New World taxa are the product of westward dispersal from Africa. Here, we present a mitochondrial DNA phylogeny ofSchistocercaspecies that supports the monophyly of New World species (including the Galapagos endemicHalmenus) relative toS. gregaria. In concert with observed patterns of molecular divergence, and in contrast to previous morphological studies, our analysis indicates a single trans-Atlantic flight from Africa to South America, followed by extensive speciation and ecological divergence in the New World.
Strong assortative mating between allopatric sticklebacks as a by-product of adaptation to different environments
Authors: Vines Timothy H , Schluter Dolph
Published: December 2005

Speciation involves the evolution of reproductive isolation between populations. One potentially important mechanism is the evolution of pre- or postzygotic isolation between populations as a by-product of adaptation to different environments. In this paper, we tested for assortative mating between allopatric stickleback populations adapted to different ecological niches. Our experimental design controlled for interpopulation interactions and non-adaptive explanations for assortative mating. We found that prezygotic isolation was surprisingly strong: when given a choice, the majority of matings occurred between individuals from similar environments. Our results indicate that the by-product mechanism is a potent source of reproductive isolation, and likely contributed to the origin of sympatric species of sticklebacks.
No extension of lifespan by ablation of germ line inDrosophila
Authors: Barnes Andrew I , Boone James M , Jacobson Jake , Partridge Linda , Chapman Tracey
Published: December 2005

Increased reproduction is frequently associated with a reduction in longevity in a variety of organisms. Traditional explanations of this ‘cost of reproduction’ suggest that trade-offs between reproduction and longevity should be obligate. However, it is possible to uncouple the two traits in model organisms. Recently, it has been suggested that reproduction and longevity are linked by molecular signals produced by specific reproductive tissues. For example, inCaenorhabditis elegans, lifespan is extended in worms that lack a proliferating germ line, but which possess somatic gonad tissue, suggesting that these tissues are the sources of signals that mediate lifespan. In this study, we tested for evidence of such gonadal signals inDrosophila melanogaster. We ablated the germ line using two maternal effect mutations:germ cell-lessandtudor. Both mutations result in flies that lack a proliferating germ line but that possess a somatic gonad. In contrast to the findings fromC. elegans, we found that germ line ablated females had reduced longevity relative to controls and that the removal of the germ line led to an over-proliferation of the somatic stem cells in the germarium. Our results contrast with the widely held view that it is downstream reproductive processes such as the production and/or laying of eggs that are costly to females. In males, germ line ablation caused either no difference, or a slight extension, in longevity relative to controls. Our results indicate that early acting, upstream reproductive enabling processes are likely to be important in determining reproductive costs. In addition, we suggest that the specific roles and putative patterns of molecular signalling in the germ line and somatic tissues are not conserved between flies and worms.
Symmetrical crypsis and asymmetrical signalling in the cuttlefishSepia officinalis
Authors: Langridge Keri V
Published: December 2005

The salience of bilateral symmetry to humans has led to the suggestion that camouflage may be enhanced in asymmetrical patterns. However, the importance of bilateral symmetry in visual signals (and overall morphology) may constrain the evolution of asymmetrical camouflage, resulting in the bilaterally symmetrical cryptic patterns that we see throughout the animal kingdom. This study investigates the cuttlefish (Sepia officinalis), which can control the degree of symmetry in its coloration. Ten juvenileS. officinaliswere filmed in two behavioural contexts (cryptic and threatened) to test the prediction that cryptic patterns will be expressed more asymmetrically than an anti-predator signal known as the ‘deimatic display’. Cryptic body patterns, particularly those with a disruptive function, were found to exhibit a high degree of bilateral symmetry. By contrast, the components of the deimatic display were often expressed asymmetrically. These results are contrary to the predicted use of symmetry in defensive coloration, indicating that the role of symmetry in both crypsis and visual signalling is not as straightforward as previously suggested.
Observational aspects of sunspot oscillations
Authors: Bogdan T.J , Judge P.G
Published: December 2005

Oscillatory phenomena observed in sunspot umbrae and penumbrae are reviewed and critically discussed. A natural interplay between the thermal atmospheric stratification and the ordered collimation imposed by the intense magnetic field leads naturally to the characteristic properties of the umbral chromospheric and photospheric oscillations and their interpretation as low-
β
(
β
=8
πp
/
B
2
) slow magneto-acoustic-gravity waves guided along the ambient magnetic field.
Dispersion relations, rays and ray splitting in magnetohelioseismology
Authors: Cally P.S
Published: December 2005

Local helioseismology seeks to probe the near surface regions of the Sun, and in particular of active regions. These are distinguished by their strong magnetic fields, yet current local techniques do not take proper account of this. Here, we first derive appropriate gravito-magneto-acoustic dispersion relations, and then use these to examine how acoustic rays entering regions of strong field split into fast and slow components, and the subsequent fates of each. Specifically, two types of transmission point, where wave energy can transfer from the fast to slow branch (or vice versa) are identified; one close to the equipartition level where the sound and Alfvén speeds coincide, and one higher up near the acoustic cutoff turning point. This second type only exists for rays of low frequency or low
l
though. In accord with recent studies of fast-to-slow mode conversion from the perspective of p-modes, magnetic field inclination is found to have significant consequences for wave splitting.
Slow magnetohydrodynamic waves in the solar atmosphere
Authors: Roberts B
Published: December 2005

There is increasingly strong observational evidence that slow magnetoacoustic modes arise in the solar atmosphere, either as propagating or standing waves. Sunspots, coronal plumes and coronal loops all appear to support slow modes. Here we examine theoretically how the slow mode may be extracted from the magnetohydrodynamic equations, considering the special case of a vertical magnetic field in a stratified medium: the slow mode is described by the Klein–Gordon equation. We consider its application to recent observations of slow waves in coronal loops.
Propagating magnetohydrodynamics waves in coronal loops
Authors: De Moortel I
Published: December 2005

High cadence Transition Region and Coronal Explorer (TRACE) observations show that outward propagating intensity disturbances are a common feature in large, quiescent coronal loops, close to active regions. An overview is given of measured parameters of such longitudinal oscillations in coronal loops. The observed oscillations are interpreted as propagating slow magnetoacoustic waves and are unlikely to be flare-driven. A strong correlation, between the loop position and the periodicity of the oscillations, provides evidence that the underlying oscillations can propagate through the transition region and into the corona. Both a one- and a two-dimensional theoretical model of slow magnetoacoustic waves are presented to explain the very short observed damping lengths. The results of these numerical simulations are compared with the TRACE observations and show that a combination of the area divergence and thermal conduction agrees well with the observed amplitude decay. Additionally, the usefulness of wavelet analysis is discussed, showing that care has to be taken when interpreting the results of wavelet analysis, and a good knowledge of all possible factors that might influence or distort the results is a necessity.
Magnetohydrodynamic waves in coronal polar plumes
Authors: Nakariakov Valery M
Published: December 2005

Polar plumes are cool, dense, linear, magnetically open structures that arise from predominantly unipolar magnetic footpoints in the solar polar coronal holes. As the Alfvén speed is decreased in plumes in comparison with the surrounding medium, these structures are natural waveguides for fast and slow magnetoacoustic waves. The simplicity of the geometry of polar plumes makes them an ideal test ground for the study of magnetohydrodynamic (MHD) wave interaction with solar coronal structures. The review covers recent observational findings of compressible and incompressible waves in polar plumes with imaging and spectral instruments, and interpretation of the waves in terms of MHD theory.
Nonlinear waves in the solar atmosphere
Authors: Ruderman Michael S
Published: December 2005

In this paper, we give a brief review of the contemporary theory of nonlinear waves in the solar atmosphere. The choice of topics reflects personal interests of the author. Historically the theory of nonlinear waves was first applied to the solar atmosphere to explain the chromospheric and coronal heating. It was assumed that the turbulent motion in the solar convective zone excites sound waves that propagate upwards. Due to nonlinearity these waves steepen and form shocks. The wave energy dissipates in these shocks thus heating the corona. We give a brief description of propagation and damping of nonlinear sound waves in the stratified solar atmosphere, and point out that, at present, the acoustic heating remains the most popular theory of heating the lower chromosphere. Then we extend the analysis to nonlinear slow magnetosonic waves in coronal plumes and loops, and discuss its implications for interpretation of observational results. The next topic of interest is the propagation of nonlinear waves in a magnetically structured atmosphere. Here, we restrict our analysis to slow sausage waves in magnetic tubes and discuss properties of solitary waves described by the Leibovich–Roberts equation. We conclude with the discussion of nonlinear theory of slow resonant layers, and its possible application to helioseismology.
Drivers of the solar wind: then and now
Authors: Hollweg Joseph V
Published: December 2005

Early spacecraft data in the 1960s revealed solar wind properties, which could not be well explained by models in which the electron pressure gradient was the principal accelerating force. The Alfvén waves discovered around 1970 were thought for a while to provide additional energy and momentum, but they ultimately failed to explain the rapid acceleration of the fast wind close to the Sun. By the late 1970s, various data were suggesting the importance of the ion-cyclotron resonance far from the Sun. This notion was soon applied to the acceleration region close to the Sun. The models, which resulted, suggested that the fast wind could be driven mainly by the proton pressure gradient. Since the mid-1990s, Solar and Heliospheric Observatory has provided remarkable data, which have verified some of the predictions of these theories, and given impetus to studies of the ion-cyclotron resonance as the principal mechanism for heating the coronal holes, and ultimately driving the fast wind. After a historical review, we discuss the basic ideas behind current research, emphasizing the particle kinetics. We discuss remaining problems, especially the source of the ion-cyclotron resonant waves.
Cognitive ornithology: the evolution of avian intelligence
Authors: Emery Nathan J
Published: December 2005

Comparative psychologists interested in the evolution of intelligence have focused their attention on social primates, whereas birds tend to be used as models of associative learning. However, corvids and parrots, which have forebrains relatively the same size as apes, live in complex social groups and have a long developmental period before becoming independent, have demonstrated ape-like intelligence. Although, ornithologists have documented thousands of hours observing birds in their natural habitat, they have focused their attention on avian behaviour and ecology, rather than intelligence. This review discusses recent studies of avian cognition contrasting two different approaches; the anthropocentric approach and the adaptive specialization approach. It is argued that the most productive method is to combine the two approaches. This is discussed with respects to recent investigations of two supposedly unique aspects of human cognition; episodic memory and theory of mind. In reviewing the evidence for avian intelligence, corvids and parrots appear to be cognitively superior to other birds and in many cases even apes. This suggests that complex cognition has evolved in species with very different brains through a process of convergent evolution rather than shared ancestry, although the notion that birds and mammals may share common neural connectivity patterns is discussed.
Persistence and stability of macroinvertebrate communities in streams of Denali National Park, Alaska: implications for biological monitoring
Authors: MILNER ALEXANDER M. , CONN SARAH C. , BROWN LEE E.
Published: January 2006

1. Macroinvertebrate communities were studied from 1994 to 2001/2002 (except 1997) in six streams in Denali National Park, interior Alaska. All six streams were potential reference streams with no known impairment.

2. Abundance of individual taxa varied markedly from year to year. Overall, abundance decreased over the study period, particularly with respect to mayflies. Stonefly taxa showed lower persistence and were sometimes absent from a stream in any particular year.

3. Mean community persistence for the six streams, as measured by Jaccard's similarity coefficients between years, varied from 0.48 in the year pair 1999–2000 to 0.78 in 1998–99. Tattler Creek (a small stable stream) supported the most persistent macroinvertebrate community and Highway Pass Creek (a small, unstable creek) the least. Mean community persistence showed a significant relationship with mean winter snowfall (November to March) for the six streams.

4. The highest community compositional stability was found in Tattler Creek and the lowest in Highway Pass Creek, but stability varied markedly over time for the six streams, peaking in 1994–95 and reaching a minimum in 2000–01. Compositional stability was significantly related to the Pfankuch Index of channel stability.

5. The composition metrics % Chironomidae, % dominant taxa, %EPT, % Ephemeroptera and % Plecoptera, employed as part of the Alaska Stream Condition Index, varied over almost their entire range in these pristine streams across the 9 years of the study.

6. This study demonstrates the wide range of natural variation that occurs in benthic macroinvertebrate communities in these pristine central Alaskan streams, potentially limiting the applicability of composition metrics for the biological monitoring of water quality in these systems.
Anasarca improved by extracorporeal ultrafiltration through an internal shunt in a case of severe haemophilia B with inhibitor and steroid‐resistant nephrotic syndrome
Authors: SATOMURA A. , TAKAHASHI S. , FUJITA T. , MATSUMOTO K. , SHICHINO H. , MUGISHIMA H.
Published: January 2006

Summary.  A patient suffering from severe haemophilia B with factor IX inhibitor developed steroid‐resistant nephrotic syndrome. As a result of switching to activated anti‐inhibitor coagulant complex (activated prothrombin complex concentrate) agent, FEIBATM), bleeding was controlled and internal shunt placement was successful, leading to control of bleeding during extracorporeal ultrafiltration (ECU) therapy. We report this case where regular ECU therapy became possible and as a result anasarca was controlled.
Sero‐epidemiological study of kala‐azar in a village of Varanasi district, India
Authors: Kumar R. , Pai K. , Kumar P. , Pandey H. P. , Sundar S.
Published: January 2006

Objective  To evaluate five kala‐azar serological tests for field use.

Method  Serological survey in Pandit Ka Purva village in Varanasi district, India, using Sia water test, aldehyde test, direct agglutination test (DAT), micro‐enzyme‐linked immunosorbent assay (ELISA) and dot‐ELISA.

Results  The total population of the village was 518, 67 of whom showed typical clinical and parasitological features of kala‐azar, including seven who died. The age distribution of kala‐azar cases showed significant differences, being highest among the 45–54‐year age group. The disease was more prevalent among males. Serum samples were collected from 498 persons (96% of total population) including 67 kala‐azar cases and 40 disease controls (malaria, TB, leprosy, typhoid). Ten 10 serum samples from healthy controls living in endemic area were also collected. The test sensitivities were: Sia water test, 85.0%; aldehyde test, 62.7%; DAT, 94.0%; micro‐ELISA, 91.0% and dot‐ELISA, 97.0%. The test specificities were: Sia water test 92.5%, aldehyde test, 93.2%, DAT, 96.7; micro‐ELISA, 97.6% and dot‐ELISA, 98.4%.

Conclusion  The dot‐ELISA is highly sensitive and specific, cheap, and easy to interpret with the naked eye, making it a powerful screening test for the surveillance and diagnosis of Indian kala‐azar at field level.
Treatment of vitiligo with broadband ultraviolet B and vitamins
Authors: Don Philip , Iuga Aurel , Dacko Anne , Hardick Kathleen
Published: January 2006

Background  While oral psoralen plus ultraviolet A (PUVA) remains the most popular therapeutic modality for vitiligo, recent reports have shown that narrowband ultraviolet B (UVB) also induces significant repigmentation. In this study we evaluated the efficacy of broadband UVB on actively spreading, progressive vitiligo in patients who had been followed for many months (12 or more) in our practice, who continued to depigment despite treatment.

Methods  Nine patients with actively spreading vitiligo were exposed to broadband UVB 2–3 times per week at a starting dose of 20–30 mJ/cm2. Radiation was increased by 10–20 mJ/cm2 per session with adjustments for symptomatic erythema or missed visits. In addition, patients took vitamin C 500 mg twice a day (BID), vitamin B12 1000 µg BID and folic acid 5 mg BID. The response to treatment and side‐effects were assessed at each visit. The patient's response to treatment and progress were assessed by photographs and by physician evaluation of body surface area (BSA) (using the Rule of 9s) involved at monthly intervals. Photographs were taken and estimations of BSA by physical examination made at the start and finish of the trial and then compared by the physicians involved in the study.

Results  Broadband UVB halted the progression of vitiligo in all nine patients and in general induced repigmentation early after 8–12 treatments (6–8 weeks). After 2–8 months of treatment, nine of nine patients achieved good (51–75%) or excellent response (76–100%). The percentage of repigmentation varied with length of treatment and anatomic site.

Conclusions  This study confirms the only published report that broadband UVB is effective on actively spreading vitiligo. Since it is more cost effective than narrowband UVB and has numerous advantages compared to oral PUVA, broadband UVB may offer an alternative for future treatment of vitiligo. The role of vitamins in this therapy remains to be determined.