bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long-term complications of bone-anchored hearing aids: a 14-year experience
Authors: Badran K , Arya A K , Bunstone D , Mackinnon N 
Published: May 2008

AbstractObjectives:To report cases of long-term surgical complications, implant failure and revision surgery, within a large bone-anchored hearing aid programme.Study design:Retrospective, case–cohort study.Setting:Tertiary referral centre.Patients:One hundred and sixty-five adults and children who had undergone a total of 177 bone-anchored hearing aid implantations.Intervention:Diagnosis and explanation of adverse events and device failure.Main outcome measures:Operative complications and survival analysis, surgical challenges related to revisions, and causes of failure.Results:Twenty-one per cent of patients (3.4 per cent of those observed) suffered from skin reactions; this rate did not increase over time. Seventeen per cent had loss of osseointegration at a median interval of 6.3 months. Loss of osseointegration was observed more frequently in patients with a 3 mm compared with a 4 mm fixture (p < 0.001). Intra-operatively, the only complication was bleeding, occurring in 3 per cent of patients. Post-operative complications included: primary bleeding (2 per cent); severe skin reactions requiring intravenous antibiotics, cautery or grafting (8 per cent); thickening or overgrowth of skin requiring excision (8 per cent); failure of osseointegration requiring a new fixture (18 per cent); and graft necrosis requiring revision (1 per cent). In two patients, it was necessary to explore the area to remove overgrowth of bone. In 16 patients (10 per cent), the bone-anchored hearing aid had to be abandoned due to failure of osseointegration (n = 4), dissatisfaction with the aid (n = 6), intolerable pain (n = 4), hair growth around the abutment (n = 1) or recurrent infections (n = 1). In 12 of these patients, the bone-anchored hearing aid was removed surgically. Overall, 57 patients (34 per cent) underwent revision surgery.Conclusion:Awareness of complications is becoming increasingly important in bone-anchored hearing aid programme. A substantial workload of device maintenance should be anticipated, and patients should be appropriately counselled beforehand. Ninety per cent of our patients chose to persevere with this form of hearing rehabilitation.
Comparison of external and endonasal dacryocystorhinostomy
Authors: Feretis M , Newton J R , Ram B , Green F 
Published: May 2008

AbstractIntroduction:External dacryocystorhinostomy has been the treatment for nasolacrimal duct obstruction for more than a century. More recently, nasal endoscopy has allowed this procedure to be carried out endonasally.Aim:The aim of this postal questionnaire study was to compare the health status of patients treated for epiphora by external versus endonasal non-laser dacryocystorhinostomy.Method:The Glasgow benefit inventory questionnaire, along with an additional, department-based symptomatic questionnaire, was distributed to all patients fitting our criteria.Results:Satisfactorily completed questionnaires were received from 64 out of 90 patients in the external group and from 30 of 41 patients in the endonasal group. Results indicated positive scores for both groups for all four subscales of the Glasgow benefit inventory. There were no statistically significant differences between results for the external and endonasal procedures. The ocular symptomatology questionnaire results indicated better scores for the external procedure, but this difference did not reach statistical significance.
Weibel instabilities in dense quantum plasmas
Authors: TSINTSADZE LEVAN N. , SHUKLA P. K. 
Published: May 2008

AbstractThe quantum effect on the Weibel instability in an unmagnetized plasma is presented. Our analysis shows that the quantum effect tends to stabilize the Weibel instability in the hydrodynamic regime, whereas it produces a new oscillatory instability in the kinetic regime. A novel effect called the quantum damping, which is associated with the Landau damping, is disclosed. The new quantum Weibel instability may be responsible for the generation of non-stationary magnetic fields in compact astrophysical objects as well as in the forthcoming intense laser–solid density plasma interaction experiments.
Hausdorff and packing measure functions of self-similar sets: continuity and measurability
Authors: OLSEN L. 
Published: May 2008

AbstractLetNbe an integer withN≥2 and letXbe a compact subset of ℝd. If$\mathsf {S}=(S_{1},\ldots ,S_{N})$is a list of contracting similaritiesSi:X→X, then we will write$K_{\mathsf {S}}$for the self-similar set associated with$\mathsf {S}$, and we will writeMfor the family of all lists$\mathsf {S}$satisfying the strong separation condition. In this paper we show that the maps(1)and(2)are continuous; here$\dim _{\mathsf {H}}$denotes the Hausdorff dimension, ℋsdenotes thes-dimensional Hausdorff measure and 𝒮sdenotes thes-dimensional spherical Hausdorff measure. In fact, we prove a more general continuity result which, amongst other things, implies that the maps in (1) and (2) are continuous.
A comparison of bird communities in the anthropogenic and natural-tree fall gaps of a reduced-impact logged subtropical forest in Bolivia
Authors: Felton Adam , Wood Jeff T. , Felton Annika M. , Lindenmayer David B. , Hennessey Bennett A. 
Published: May 2008

AbstractWe studied bird community composition and abundance within four vegetation and disturbance categories located within selectively logged and unlogged forest in a Bolivian subtropical lowland forestry concession. The logged forest was subject to reduced-impact logging between 1 and 4 years prior to our study. The four categories were: 1) ‘gap’ points possessing natural or anthropogenic tree-fall gaps; 2) ‘target’ points with one of five commercial tree species of harvestable size; 3) ‘future’ points possessing a commercial tree below harvestable size and 4) ‘non-target’ points not possessing harvestable tree species. The bird community composition of logging gaps significantly differed from that found within natural tree-fall gaps in the unlogged forest P< 0.05. Species richness was higher in natural tree-fall gaps than in anthropogenic gaps. Furthermore, a higher proportion of disturbance sensitive species were associated with natural-tree fall gaps, whereas a higher proportion of disturbance tolerant species were associated with anthropogenic gaps. No significant difference was detected in the bird community composition for the other three vegetation categories surveyed. We discuss the conservation and silvicultural repercussions of these results.
Population dynamics and spatial distribution of Griffon Vultures (Gyps fulvus) in Portugal
Authors: van Beest Floris , van den Bremer Loes , de Boer Willem F. , Heitkönig Ignas M. A. , Monteiro Antonio E. 
Published: May 2008

AbstractThe global decrease of vulture populations has been attributed to several factors, such as food availability, poisoning, human disturbance, or habitat suitability. We studied the effect of factors that vary both spatially and temporally on the nest site distribution of the Griffon Vulture Gyps fulvus in northeast Portugal, and influence the population dynamics of these cliff-dwelling birds. Several demographic parameters were studied in the field, and the age structure of the population was determined. Additionally we investigated how food availability affected population fluctuations. The vulture population was most sensitive to juvenile mortality according to our model results. Our models showed that a decrease in the present food supply resulted in a decrease in vulture abundance and, moreover, negatively affected the spatial distribution of the species by decreasing the number of breeding pairs per colony. The total quantity of sheep and goat biomass, a greater distance to the nearest unpaved road, and the presence of Egyptian Vultures Neophron percnopterus at the breeding colonies showed a significant positive relationship to the numbers of Griffon Vulture breeding pairs. It is recommended that the available food supply in the most important foraging areas should be monitored and protected. Furthermore, to manage the community of cliff breeding raptors adequately, future research should identify and protect the most suitable breeding areas for each species. Human disturbance should be kept to a minimum by protecting breeding areas, especially in an area like Riba-Côa where species such as the Egyptian Vulture, Bonelli's Eagle Hieraaetus fasciatus and Griffon Vulture breed so close to each other.
The efficacy of hand-rearing penguin chicks: evidence from African Penguins (Spheniscus demersus) orphaned in the Treasure oil spill in 2000
Authors: Barham Peter J. , Underhill Les G. , Crawford Robert J. M. , Altwegg Res , Mario Leshoro T. , Bolton Duncan A. , Dyer Bruce M. , Upfold Leshia 
Published: May 2008

AbstractSome 2,000 orphaned chicks of African Penguins Spheniscus demersus were hand-reared and released back into the wild on Robben and Dassen Islands following the Treasure oil spill in June 2000. Of these chicks, 1,787 were flipper banded. This paper reports on the subsequent survival rate and breeding success of those individuals seen on Robben Island from 2001–2006. Survival to breeding age and their subsequent breeding success of hand-reared chicks was no different from that of naturally-reared chicks. Over a four-year period, pairs where at least one partner was a hand-reared chick produced an average of more than 1.6 chicks per year. Combining the data on survival with that on breeding success indicates that 1,000 hand-reared chicks will produce around 1,220 chicks themselves over their lifetimes, making this a worthwhile conservation intervention.
Nesting biology and population dynamics of Jankowski's Bunting Emberiza jankowskii in Western Jilin, China
Authors: Jiang Yun-Lei , Gao Wei , Lei Fu-Min , Wang Hai-Tao , Wan Dong-Mei , Zhao Jiang 
Published: May 2008

AbstractJankowski's Bunting Emberiza jankowskii is endemic to China, Russia and Northern Korea, and was listed as a ‘Vulnerable’ species. The population in Dagang Forestry of western Jilin is one of the small remaining discrete breeding populations in the species' range. Very little information on the nesting biology and population dynamics has previously been published. We studied the nesting biology from 1999 to 2002 and population dynamics of the bunting from 1999 to 2006 (except 2003). A total of 74 nesting attempts were monitored. Jankowski's Bunting breeding season began in late April and usually ended in late July. Both sexes participated in nest-building, feeding young and defending the nest. Mean full clutch size for three years combined was 5.26 ± 0.76 eggs, and ranged from four to seven. Clutch size decreased with nest-initiation date. Mean hatching rate was 41.2%. Overall probability of Mayfield nest success to fledging was low for the three years, averaging 0.218 ± 0.007. The factors leading to low nest success include nest parasitization, nest predation, human activities and nest abandonment. Low survival of Jankowski's Bunting nests may be a factor in declining populations and the slow recovery of populations because of low recruitment at the population and the individual level. The population of Jankowski's Bunting in the Dagang Forestry grassland was small and declined dramatically from 1999 to 2006. The main threat is habitat loss and fragmentation due to agriculture, tree planting and housing following human colonization of the region. The habitat has been reduced in extent by c. 70% since the 1960s. In addition, grazing by domestic livestock dramatically destroyed their preferred vegetation. Furthermore, the restriction to several small, discrete sites makes the bunting inherently vulnerable to catastrophic and stochastic events that can eliminate subpopulations. Jankowski's bunting is one of the most threatened species in China and faces an unpredictable future. Maintaining the structure and general composition of remaining Jankowski's Bunting nesting habitat is important to ensure continued presence of this species in western Jilin and worldwide.
The Distribution of Ascents of Size d or More in Partitions of n
Authors: BRENNAN CHARLOTTE , KNOPFMACHER ARNOLD , WAGNER STEPHAN 
Published: May 2008

A partition of a positive integer n is a finite sequence of positive integers a1, a2, . . ., ak such that a1+a2+ċ ċ ċ+ak=n and ai+1 ≥ ai for all i. Let d be a fixed positive integer. We say that we have an ascent of size d or more if ai+1 ≥ ai+d.We determine the mean, the variance and the limiting distribution of the number of ascents of size d or more (equivalently, the number of distinct part sizes of multiplicity d or more) in the partitions of n.
Activation of the spinal sigma‐1 receptor enhances NMDA‐induced pain via PKC‐ and PKA‐dependent phosphorylation of the NR1 subunit in mice
Authors: Kim H‐W , Roh D‐H , Yoon S‐Y , Seo H‐S , Kwon Y‐B , Han H‐J , Kim K‐W , Beitz A J , Lee J‐H 
Published: May 2008

Background and purpose:Previously we demonstrated that the spinal sigma‐1 receptor (Sig‐1 R) plays an important role in pain transmission, although the exact mechanism is still unclear. It has been suggested that Sig‐1 R agonists increase glutamate‐induced calcium influx through N‐methyl‐D‐aspartate (NMDA) receptors. Despite data suggesting a link between Sig‐1 Rs and NMDA receptors, there are no studies addressing whether Sig‐1 R activation directly affects NMDA receptor sensitivity.Experimental approach:We studied the effect of intrathecal (i.t.) administration of Sig‐1 R agonists on protein kinase C (PKC) and protein kinase A (PKA) dependent phosphorylation of the NMDA receptor subunit NR1 (pNR1) as a marker of NMDA receptor sensitization. In addition, we examined whether this Sig‐1 R mediated phosphorylation of NR1 plays an important role in sensory function using a model of NMDA‐induced pain.Key results:Both Western blot assays and image analysis of pNR1 immunohistochemical staining in the spinal cord indicated that i.t. injection of the Sig‐1 R agonists, PRE‐084 or carbetapentane dose dependently enhanced pNR1 expression in the murine dorsal horn. This increased pNR1 expression was significantly reduced by pretreatment with the specific Sig‐1 R antagonist, BD‐1047. In another set of experiments Sig‐1 R agonists further potentiated NMDA‐induced pain behaviour and pNR1 immunoreactivity and this was also reversed with BD‐1047.Conclusions and implications:The results of this study suggest that the activation of spinal Sig‐1 R enhances NMDA‐induced pain via PKC‐ and PKA‐dependent phosphorylation of the NMDA receptor NR 1 subunit.British Journal of Pharmacology (2008) 154, 1125–1134; doi:10.1038/bjp.2008.159; published online 19 May 2008
Pharmacokinetic–pharmacodynamic modelling of fluvoxamine 5‐HT transporter occupancy in rat frontal cortex
Authors: Geldof M , Freijer J I , Van Beijsterveldt L , Langlois X , Danhof M 
Published: May 2008

Background and purpose:The pharmacokinetic–pharmacodynamic (PK–PD) correlation of fluvoxamine 5‐HT transporter (SERT) occupancy was determined in rat frontal cortexex vivo.Experimental approach:Rats (n=47) with permanent arterial and venous cannulas received a 30 min intravenous infusion of fluvoxamine (1 or 7.3 mg kg−1). At various time points after dosing, brains were collected for determination of fluvoxamine concentration and SERT occupancy. In addition, the time course of fluvoxamine concentration in plasma was determined up to the time of brain collection. In a separate study (n=26), the time course of fluvoxamine concentration in brain extracellular fluid (ECF) and plasma was determined. The results of the investigations were interpreted by nonlinear mixed effects modelingKey results:Highest SERT occupancy was reached at the first time point (10 or 15 min) and maintained for 1.5 and 7 h after 1 and 7.3 mg kg−1, respectively. Thereafter, SERT occupancy decreased linearly at a rate of 8% h−1. SERT occupancy could be directly related to plasma, brain ECF and brain tissue concentrations by a hyperbolic function (Bmaxmodel). Maximal SERT occupancy (Bmax) was 95%. Estimated concentrations at half‐maximal SERT occupancy (EC50) in plasma, ECF and brain tissue were 0.48, 0.22 and 14.8 ng mL−1respectively. The minimum value of the objective function decreased 12 points for ECF and brain tissue concentrations relative to plasma (P<0.01), presumably as a result of nonlinear brain distribution.Conclusions and implications:The proposed PK–PD model constitutes a useful basis for prediction of the time course ofex vivoSERT occupancy in behavioural studies with selective serotonin reuptake inhibitors.British Journal of Pharmacology(2008)154, 1369–1378; doi:10.1038/bjp.2008.179; published online 19 May 2008
Melatonin receptors, heterodimerization, signal transduction and binding sites: what's new?
Authors: Jockers R , Maurice P , Boutin J A , Delagrange P 
Published: May 2008

Melatonin is a neurohormone that has been claimed to be involved in a wide range of physiological functions. Nevertheless, for most of its effects, the mechanism of action is not really known. In mammals, two melatonin receptors, MT1and MT2, have been cloned. They belong to the G‐protein‐coupled receptor (GPCR) superfamily. They share some specific short amino‐acid sequences, which suggest that they represent a specific subfamily. Another receptor from the same subfamily, the melatonin‐related receptor has been cloned in different species including humans. This orphan receptor also named GPR50 does not bind melatonin and its endogenous ligand is still unknown. Nevertheless, this receptor has been shown to behave as an antagonist of the MT1receptor, which opens new pharmacological perspectives for GPR50 despite the lack of endogenous or synthetic ligands. Moreover, MT1and MT2interact together through the formation of heterodimers at least in cells transfected with the cDNA of these two receptors. Lastly, signalling complexes associated with MT1and MT2receptors are starting to be deciphered. A third melatonin‐binding site has been purified and characterized as the enzyme quinone reductase 2 (QR2). Inhibition of QR2 by melatonin may explain melatonin's protective effect that has been reported in different animal models and that is generally associated with its well‐documented antioxidant properties.British Journal of Pharmacology(2008)154, 1182–1195; doi:10.1038/bjp.2008.184; published online 19 May 2008
Role of calcium in substance P‐induced chemokine synthesis in mouse pancreatic acinar cells
Authors: Ramnath R D , Sun J , Bhatia M 
Published: May 2008

Background and purpose:Substance P (SP) and chemokines play critical roles in acute pancreatitis. SP elevates cytosolic calcium in pancreatic acinar cells and elevated cytosolic calcium is thought to be an early event in the pathogenesis of acute pancreatitis. SP induces production of chemokines MCP‐1, MIP‐1α and MIP‐2 in pancreatic acinar cells, however the exact mechanism by which SP stimulates the production of these pro‐inflammatory mediators remain undetermined. The aim of the present study is to investigate the role of calcium in SP‐induced chemokine production in pancreatic acinar cells and to establish the signal transduction mechanisms involved.Experimental approach:An in vitro model of isolated mouse pancreatic acinar cells was used. Western blotting analysis, ELISA and calcium measurement were performed.Key results:SP increased chemokine secretion through the activation of PKCα/βII, MAPKinases (ERK and JNK), NFκB and AP‐1 in pancreatic acinar cells. These effects were blocked by pretreatment of the cells with the specific calcium chelator BAPTA‐AM. Moreover, SP‐induced activation of PKCα/βII, ERK, JNK, NF‐κB, AP‐1 and chemokine production was inhibited by the specific phospholipase C inhibitor U73122.Conclusions and implications:SP‐induced chemokine production in pancreatic acinar cells resulted from PLC‐induced elevated intracellular calcium and PKCα/βII activation, subsequently leading to the activation of MAPKinases (ERK and JNK) and transcription factors NF‐κB and AP‐1. The present study demonstrates the critical role of calcium in SP‐induced chemokine production in pancreatic acinar cells. Drugs targeting the SP‐calcium mediated signaling pathways could prove beneficial in improving the treatment of acute pancreatitis.British Journal of Pharmacology (2008) 154, 1339–1348; doi:10.1038/bjp.2008.188; published online 19 May 2008
Chronic inhibition of the Na+/H+‐ exchanger causes regression of hypertrophy, heart failure, and ionic and electrophysiological remodelling
Authors: Baartscheer A , Hardziyenka M , Schumacher C A , Belterman C N W , Van Borren M M G J , Verkerk A O , Coronel R , Fiolet J W T 
Published: May 2008

Background and purpose:Increased activity of the Na+/H+‐exchanger (NHE‐1) in heart failure underlies raised [Na+]icausing disturbances of calcium handling. Inhibition of NHE‐1, initiated at the onset of pressure/volume overload, prevents development of hypertrophy, heart failure and remodelling. We hypothesized that chronic inhibition of NHE‐1, initiated at a later stage, would induce regression of hypertrophy, heart failure, and ionic and electrophysiological remodelling.Experimental approach:Development of heart failure in rabbits was monitored electrocardiographically and echocardiographically, after one or three months. Cardiac myocytes were also isolated. One group of animals were treated with cariporide (inhibitor of NHE‐1) in the diet after one month. Cytoplasmic calcium, sodium and action potentials were measured with fluorescent markers and sarcoplasmic reticulum calcium content by rapid cooling. Calcium after‐transients were elicited after rapid pacing. Sodium channel current(INa) was measured using patch‐clamp techniques.Key results:Hypertrophy and heart failure developed after one month and progressed during the next two months. After one month, dietary treatment with cariporide was initiated. Two months of treatment reduced hypertrophy and heart failure, duration of action potential QT‐interval and QRS, and restored sodium and calcium handling and the incidence of calcium after‐transients. In cardiac myocytes, parameters ofINawere not changed by cariporide.Conclusion and implications:In rabbit hearts with hypertrophy and signs of heart failure one month after induction of pressure/volume overload, two months of dietary treatment with the NHE‐1 inhibitor cariporide caused regression of hypertrophy, heart failure and ionic and electrophysiological remodelling.British Journal of Pharmacology(2008)154, 1266–1275; doi:10.1038/bjp.2008.189; published online 19 May 2008