bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of gender on clinical presentation of chronic rhinosinusitis with and without polyposis
Authors: Busaba N Y , Sin H-J , Salman S D
Published: February 2008

Study objective:

To determine the impact of a patient's gender on the clinical presentation of chronic rhinosinusitis with and without nasal polyposis.

Study design and methods:

Prospective study of 514 adult patients who presented with chronic rhinosinusitis with and without nasal polyposis. The patients were divided into two groups based on gender: female (n = 273) and male (n = 241). The following data were collected: presenting symptoms, co-morbidities, nasal endoscopy and sinus computed tomography findings, diagnosis, and outcome of surgery. Statistical analysis was performed using the chi-square test, with statistical significance set at p < 0.05.

Results:

Facial pain and headache were more prevalent among women, while nasal obstruction was more prevalent among men (p < 0.05). There was no statistically significant difference in the prevalence of environmental allergy, asthma, psychiatric illness or anatomical variants obstructing the osteomeatal unit, comparing the genders. Chronic rhinosinusitis without polyposis was the more common diagnosis among women, while chronic rhinosinusitis with polyposis was the more common diagnosis among men (p < 0.05). Following surgery, a higher percentage of male patients reported improvement in nasal obstruction (p < 0.05), but there was no statistically significant difference in the improvement of the other presenting symptoms, comparing the genders.

Conclusion:

Women who suffer from chronic rhinosinusitis are more likely to complain of facial pain or headache on presentation and to be diagnosed with chronic rhinosinusitis without polyposis. On the other hand, men are more likely to complain of nasal obstruction, to be diagnosed with chronic rhinosinusitis with polyposis, and to report improvement in nasal obstruction following surgery.
A brief history of olfaction and olfactometry
Authors: Philpott C M , Bennett A , Murty G E
Published: February 2008

The sense of smell has been a cause for speculation and fascination over the centuries. An appreciation of odours has been deeply rooted in many cultures, including ancient civilisations such as the Egyptians. The level of understanding of the anatomy and physiology of olfaction which our ancestors had was slight, and much remains to be discovered. This paper explores the progression of knowledge over the years to the present day. Particular emphasis is placed on odour classification and olfactometry, and on the techniques whereby great scientific minds have sought to quantify that human sense which is arguably least quantifiable. A review of some of the current methods of olfactometry is included within this remit.
Decibel levels during extracorporeal lithotripsy for salivary stones
Authors: Fritsch M H
Published: February 2008

Purpose:

To determine the decibel sound pressure levels generated during extracorporeal lithotripsy for salivary stones, and if such lithotriptor noise levels have the potential for acoustic trauma.

Patients and materials:

Minilith SL-1 salivary gland lithotriptor, sound level meter; five patient survey.

Methods:

Decibel measurements were conducted on the lithotripter-generated sounds, using a sound level meter at specific distances from the active element. In addition, a patient survey was conducted as a cross-reference, to enable comparison of predicted results with actual human perception of sound levels.

Results:

Sound levels ranged between 68 and 80 dB during treatment sessions, for both the lithotriptor operator and the patient.

Conclusion:

During routine use, no acoustic trauma is incurred by either the lithotriptor operator or the patient.
Oculomotor nerve palsy after functional endoscopic sinus surgery
Authors: Chng E , Yip C-C , Lee J C Y
Published: February 2008

We report an unusual case of partial oculomotor nerve palsy occurring after functional endoscopic sinus surgery, without anatomical disruption of the extra-ocular muscles. The clinical course and possible pathogenic mechanisms are also presented.
Unilateral hearing loss as primary symptom of craniopharyngioma in a six-year-old girl
Authors: Hofman R , Rosingh H J
Published: February 2008

Objective:

We report a rare case of otological presentation of craniopharyngioma.

Method:

Case report and review of world literature concerning presentations of craniopharyngioma.

Results:

A six-year-old girl was referred to our department with unilateral hearing loss. This appeared to be a complete sensorineural hearing loss. Otoacoustic emissions were reproducible on both sides. Magnetic resonance scanning revealed a massive, cystic craniopharyngioma exerting pressure on the patient's ventricular system and brainstem and also invading the internal acoustic canal. The mass was resected via a craniotomy. The patient's hearing loss completely recovered, and she experienced no neurological or endocrinological side effects of the treatment. Craniopharyngioma have a prevalence of 0.13–2:100 000.

Conclusion:

Craniopharyngioma is a rare disease. First presentation with otological symptoms is extremely rare. Otoacoustic emissions can differentiate between cochlear and retrocochlear causes of sensorineural hearing loss.
Does hormone replacement therapy in post-menopausal women have any effect upon nasal physiology?
Authors: Wild D C , Philpott C M , Wolstenholme C R , Murty G E
Published: February 2008

Background:

Previous studies have suggested that the female menstrual cycle, pregnancy and the oral contraceptive pill have an effect upon nasal physiology.

Objectives:

This study aimed to assess the effects upon nasal physiology of female hormone replacement therapy in post-menopausal women. This has not been previously studied.

Methods:

Twenty post-menopausal women (age range 36 to 70 years; mean age 57.0 years) underwent measurements of the nasal airway, including anterior rhinoscopy, peak nasal inspiratory flow rate, acoustic rhinometry, anterior rhinomanometry, mucociliary clearance time and rhinitis quality of life questionnaire. Measurements of nasal patency were recorded prior to commencing hormone replacement therapy and at a time point 77–195 days (mean 101.9 days) following commencement.

Results:

There was no statistical difference found for any of the variables, using the paired t-test (p > 0.05 for all).

Conclusions:

Female hormone replacement therapy has no discernable effect upon nasal physiology and should not be considered a cause of rhinitic symptoms.
Tension pneumo-orbit treated by endoscopic, endonasal decompression: case report and literature review
Authors: Al-Shammari L , Majithia A , Adams A , Chatrath P
Published: February 2008

Objective:

We present a 38-year-old man with a tension pneumo-orbit following medial orbital wall fracture, managed with endoscopic decompression.

Method:

A case report and a review of the world literature concerning the aetiology, clinical features and management of medial orbital wall fractures are presented.

Results:

Our patient presented with a post-traumatic tension pneumo-orbit exacerbated by air travel and nose-blowing. Computed tomography revealed a fracture of the ethmoid bone, and intra-orbital emphysema causing proptosis. Management with endoscopic, endonasal surgery produced excellent results, with decompression achieved and immediate and sustained improvement in visual acuity.

Conclusion:

A search of the world literature revealed no documented cases of tension pneumo-orbit as a complication of medial orbital wall fracture. Endoscopic sinus surgery is currently used in the management of nasal and sinus diseases and their orbital complications. We discuss this extended indication of endoscopic surgery, and its advantages over other surgical approaches.
Intralesional triamcinolone acetonide injection in hypertrophic skin surrounding the percutaneous titanium implant of a bone-anchored hearing aid
Authors: Van Rijswijk J B , Mylanus E A M
Published: February 2008

Objective:

We present a patient with persistent hypertrophic skin surrounding the percutaneous implant of a bone-anchored hearing aid system, successfully treated with intralesional applied corticosteroids.

Method:

Case report and review of the world literature concerning bone-anchored hearing aid implantation and intralesional applied corticosteroids for the treatment of hypertrophic scars and keloids.

Results:

Eight weeks after revision surgery to reduce surplus skin and subcutaneous scar tissue overgrowing the abutment, skin and subcutaneous scar tissue overgrowth reoccurred. As an alternative to yet another surgical procedure, the hypertrophic skin was treated with intralesional injections of triamcinolone acetonide. Three weeks after the treatment, a satisfying result was seen, and no subsequent relapse was observed.

Conclusion:

To our knowledge, this is the first, photographically well documented case report of a patient with persistent hypertrophic skin surrounding a percutaneous bone-anchored hearing aid implant, successfully treated with intralesional applied corticosteroids.
Of mice and men: asymmetric interactions betweenBordetellapathogen species
Authors: RESTIF O. , WOLFE D. N. , GOEBEL E. M. , BJORNSTAD O. N. , HARVILL E. T.
Published: February 2008

In a recent experiment, we found that mice previously infected withBordetella pertussiswere not protected against a later infection withBordetella parapertussis, while primary infection withB. parapertussisconferred cross-protection. This challenges the common assumption made in most mathematical models for pathogenic strain dynamics that cross-immunity between strains is symmetric. Here we investigate the potential consequences of this pattern on the circulation of the two pathogens in human populations. To match the empirical dominance ofB. pertussis, we made the additional assumption thatB. parapertussispays a cost in terms of reduced fitness. We begin by exploring the range of parameter values that allow the coexistence of the two pathogens, with or without vaccination. We then track the dynamics of the system following the introduction of anti-pertussis vaccination. Our results suggest that (1) in order forB. pertussisto be more prevalent thanB. parapertussis, the former must have a strong competitive advantage, possibly in the form of higher infectivity, and (2) because of asymmetric cross-immunity, the introduction of anti-pertussis vaccination should have little effect on the absolute prevalence ofB. parapertussis. We discuss the evidence supporting these predictions, and the potential relevance of this model for other pathogens.
Sex differences in healthy life expectancy from self-perceived assessments of health in the City of São Paulo, Brazil
Authors: CAMARGOS MIRELA CASTRO SANTOS , MACHADO CARLA JORGE , RODRIGUES ROBERTO NASCIMENTO
Published: February 2008

Whether life is spent in good health or disability has a critical influence on the use of health-care services. It is also known that average healthy life expectancy differs by sex. This paper reports estimations of healthy and unhealthy life expectancy in old age using self-reported health assessments for the City of São Paulo, Brazil in 2000–01. The data derived from the Health, Well-being and Aging in Latin America and the Caribbean Project (SABE), and from population censuses and mortality statistics. Sullivan's estimation method was used. It combines the age-specific schedule of the current probabilities of death with the prevalence of self-perceived ‘poor’ and ‘good’ health. The paper also reports multivariate analyses of the factors associated with variations by age group and sex in self-perceived health. The findings revealed that, at all ages, women live longer than men and for more years in a healthy state. Among men, those aged 60, 65 and 70 years were expected to live a higher percentage of their remaining life than women in a healthy state, but among those aged 75, 80 and 85 years, the opposite held. Among women, the percentage of remaining years that were unhealthy did not increase as age increased, which differs from previous findings. The multivariate analyses showed that with increasing age, for women the number of chronic diseases decreased but dependency increased, and for men the opposite held. This finding indicated that the percentage of life spent in poor self-perceived health more accurately predicts mortality in men than women.
Giving help in return: family reciprocity by older Singaporeans
Authors: VERBRUGGE LOIS M. , CHAN ANGELIQUE
Published: February 2008

Reciprocity is a powerful principle in social ties. The ethos of family reciprocity is especially strong in Asian societies. We study contemporaneous family exchanges, hypothesising that the more current help older Singaporeans receive from family, the more they give in return. Cross-sectional analyses were undertaken of data from two national Singapore surveys conducted in 1995 and 1999. The help received by older people is measured by income and cash support, payment of household expenses by others, having a companion for away-from-home activities, and having a principal carer. The help given by older people is measured by baby-sitting, doing household chores, giving financial help to children, and advising on family matters. Multivariate models are used to examine the factors that affect an older person's ability and willingness to give help. The results show that the more financial support Singapore seniors received from kin, the more baby-sitting and chores they provided. In their swiftly modernising society, Singapore seniors are maintaining family reciprocity by giving time in return for money. We discuss how during the coming decades, reciprocity in Southeast and East Asian societies may shift from instrumental to more affective behaviours.
Perceptions of negative stereotypes of older people in magazine advertisements: comparing the perceptions of older adults and college students
Authors: ROBINSON TOM , GUSTAFSON BOB , POPOVICH MARK
Published: February 2008

Negative stereotypes not only affect how older people feel about themselves, but also how younger people feel about old age and their prospect of growing old. The research reported in this paper has examined the negative and potentially harmful stereotypes of older people portrayed in magazine advertisements in the United States, as perceived by groups of older and young people.Q-methodology sorts of 40 advertisements with negative images of older people, along with personal interviews, were used to probe older people's and college student's feelings and attitudes about the images. The subjects were placed in four categories: ‘moralists’, ‘objectors’, ‘ageing moralists’ and ‘resentfuls’. Regardless of whether stereotypes were used, the older people liked the advertisements that showed them as being clever, vibrant and having a sense of humour. Neither the older people nor the students liked advertisements that ridiculed or poked fun at older people, or presented them as being out of touch with reality and unattractive. Both groups rated the stereotypes dealing with the real problems associated with ageing as inoffensive. The comparison of the two age groups showed a strong consensus about which images were acceptable and which offensive.
Third Mac Lane cohomology
Authors: BAUES HANS–JOACHIM , JIBLADZE MAMUKA , PIRASHVILI TEIMURAZ
Published: February 2008

MacLane cohomology is an algebraic version of the topological Hochschild cohomology. Based on the computation of the third author (see Appendix) we obtain an interpretation of the third Mac Lane cohomology of rings using certain kind of crossed extensions of rings in the quadratic world. Actually we obtain two such interpretations corresponding to the two monoidal structures on the category of square groups.
In-homogenous self-similar measures and their Fourier transforms
Authors: OLSEN L. , SNIGIREVA N.
Published: February 2008

LetSj: ℝd→ ℝdforj= 1, . . .,Nbe contracting similarities. Also, let (p1,. . .,pN,p) be a probability vector and let ν be a probability measure on ℝdwith compact support. We show that there exists a unique probability measure μ such thatThe measure μ is called an in-homogenous self-similar measure. In this paper we study the asymptotic behaviour of the Fourier transforms of in-homogenous self-similar measures. Finally, we present a number of applications of our results. In particular, non-linear self-similar measures introduced and investigated by Glickenstein and Strichartz are special cases of in-homogenous self-similar measures, and as an application of our main results we obtain simple proofs of generalizations of Glickenstein and Strichartz's results on the asymptotic behaviour of the Fourier transforms of non-linear self-similar measures.
Periodic cohomology and subgroups with bounded Bredon cohomological dimension
Authors: HYUN JO JANG , NUCINKIS BRITA E. A.
Published: February 2008

Mislin and Talelli showed that a torsion-free group in$\HF$with periodic cohomology after some steps has finite cohomological dimension. In this note we look at similar questions for groups with torsion by considering Bredon cohomology. In particular we show that every elementary amenable group acting freely and properly on some$\R^n$×Smadmits a finite dimensional model for$\E$G.
New constraints on the Pb and Nd isotopic evolution of NE Atlantic water masses
Authors: Muiños S. B. , Frank M. , Maden C. , Hein J. R. , van de Flierdt T. , Lebreiro S. M. , Gaspar L. , Monteiro J. H. , Halliday A. N.
Published: February 2008

Time series of lead (Pb) and neodymium (Nd) isotope compositions were measured on three ferromanganese crusts recording the evolution of NE Atlantic water masses over the past 15 Ma. The crusts are distributed along a depth profile (∼700–4600 m) comprising the present‐day depths of Mediterranean Outflow Water and North East Atlantic Deep Water. A pronounced increase of the 206Pb/204Pb in the two deeper crusts starting at ∼4 Ma and a decrease in 143Nd/144Nd in all three crusts took place between ∼6–4 Ma and the present. These patterns are similar to isotope time series in the western North Atlantic basin and are consistent with efficient mixing between the two basins. However, the changes occurred 1–3 Ma earlier in the eastern basin indicating that the northeastern Atlantic led the major change in Pb and Nd isotope composition, probably due to a direct supply of Labrador Seawater via a northern route. The Pb isotope evolution during the Pliocene‐Pleistocene can generally be explained by mixing between two end‐members corresponding to Mediterranean Outflow Water and North East Atlantic Deep Water, but external sources such as Saharan dust are likely to have played a role as well. The Pb isotope composition of the shallowest crust that grew within the present‐day Mediterranean Outflow Water does not show significant Pb isotope changes indicating that it was controlled by the same Pb sources throughout the past 15 Ma.
Longitudinal plasma density variations at Saturn caused by hot electrons
Authors: Delamere P. A. , Bagenal F.
Published: February 2008

A non‐thermal tail to the electron distribution function has been measured in the inner magnetospheres of both Jupiter and Saturn. These “hot” electrons are only a small fraction (<1%) of the total electron density, yet their influence on the gas tori at Jupiter and Saturn is significant. We explore the role of hot electrons in both systems using a simplified homogeneous physical chemistry model. Our results suggest that the hot electrons are a dominant source of energy input into the Io plasma torus. This energy input is required to sustain the ∼TW of power radiated in the UV and EUV as well as to sustain the high ionization state of the torus. At Saturn, the energy input is negligible, but the hot electrons dominate ionization. We propose that the observed azimuthal electron density modulation at Saturn is caused by an azimuthally varying hot electron abundance.
Reversal of the 1960s to 1990s freshening trend in the northeast North Atlantic and Nordic Seas
Authors: Holliday N. Penny , Hughes S. L. , Bacon S. , Beszczynska‐Möller A. , Hansen B. , Lavín A. , Loeng H. , Mork K. A. , Østerhus S. , Sherwin T. , Walczowski W.
Published: February 2008

Hydrographic time series in the northeast North Atlantic and Nordic Seas show that the freshening trend of the 1960s–1990s has completely reversed in the upper ocean. Since the 1990s temperature and salinity have rapidly increased in the Atlantic Inflow from the eastern subpolar gyre to the Fram Strait. In 2003–2006 salinity values reached the previous maximum last observed around 1960, and temperature values exceeded records. The mean properties of the Atlantic Inflow decrease northwards, but variations seen in the eastern subpolar gyre at 57°N persist with the same amplitude and pattern along the pathways to Fram Strait. Time series correlations and extreme events suggest a time lag of 3–4 years over that distance. This estimate allows predictions to be made; the temperature of Atlantic water in the Fram Strait may start to decline in 2007 or 2008, salinity a year later, but both will remain high at least until 2010.
Influence of salinity on the interannual heat storage trends in the Atlantic estimated from altimeters and Pilot Research Moored Array in the Tropical Atlantic data
Authors: Sato O. T. , Polito P. S.
Published: February 2008

Changes in the oceanic heat storage (HS) can reveal important evidences of climate variability related to ocean heat fluxes. Specifically, long‐term variations in HS are a powerful indicator of climate change as HS represents the balance between the net surface energy flux and the poleward heat transported by the ocean currents. HS is estimated from sea surface height anomaly measured from the altimeters TOPEX/Poseidon and Jason 1 from 1993 to 2006. To characterize and validate the altimeter‐based HS in the Atlantic, we used the data from the Pilot Research Moored Array in the Tropical Atlantic (PIRATA) array. Correlations and rms differences are used as statistical figures of merit to compare the HS estimates. The correlations range from 0.50 to 0.87 in the buoys located at the equator and at the southern part of the array. In that region the rms differences range between 0.40 and 0.51 × 109 Jm−2. These results are encouraging and indicate that the altimeter has the precision necessary to capture the interannual trends in HS in the Atlantic. Albeit relatively small, salinity changes can also have an effect on the sea surface height anomaly. To account for this effect, NCEP/GODAS reanalysis data are used to estimate the haline contraction. To understand which dynamical processes are involved in the HS variability, the total signal is decomposed into nonpropagating basin‐scale and seasonal (HSl) planetary waves, mesoscale eddies, and small‐scale residual components. In general, HSl is the dominant signal in the tropical region. Results show a warming trend of HSl in the past 13 years almost all over the Atlantic basin with the most prominent slopes found at high latitudes. Positive interannual trends are found in the halosteric component at high latitudes of the South Atlantic and near the Labrador Sea. This could be an indication that the salinity anomaly increased in the upper layers during this period. The dynamics of the South Atlantic subtropical gyre could also be subject to low‐frequency changes caused by a trend in the halosteric component on each side of the South Atlantic Current.
Interannual variability of Greenland winter precipitation sources: Lagrangian moisture diagnostic and North Atlantic Oscillation influence
Authors: Sodemann H. , Schwierz C. , Wernli H.
Published: February 2008

We present a new Lagrangian diagnostic for identifying the sources of water vapor for precipitation. Unlike previous studies, the method allows for a quantitative demarcation of evaporative moisture sources. This is achieved by taking into account the temporal sequence of evaporation into and precipitation from an air parcel during transport, as well as information on its proximity to the boundary layer. The moisture source region diagnostic was applied to trace the origin of water vapor for winter precipitation over the Greenland ice sheet for 30 selected months with pronounced positive, negative, and neutral North Atlantic Oscillation (NAO) index, using the European Centre for Medium‐Range Weather Forecasts' ERA‐40 reanalysis data. The North Atlantic and the Nordic seas proved to be the by far dominant moisture sources for Greenland. The location of the identified moisture sources in the North Atlantic basin strongly varied with the NAO phase. More specifically, the method diagnosed a shift from sources north of Iceland during NAO positive months to a maximum in the southeastern North Atlantic for NAO negative months, qualitatively consistent with changes in the concurrent large‐scale mean flow. More long‐range moisture transport was identified during the NAO negative phase, leading to the advection of moisture from more southerly locations. Different regions of the Greenland ice sheet experience differing changes in the average moisture source locations; variability was largest in the north and west of Greenland. The strong moisture source variability for Greenland winter precipitation with the NAO found here can have a large impact on the stable isotope composition of Greenland precipitation and hence can be important for the interpretation of stable isotope data from ice cores. In a companion paper, the implications of the present results are further explored in that respect.
A cloud‐resolving modeling study of cloud radiative effects on tropical equilibrium states
Authors: Gao Shouting
Published: February 2008

The radiative effects of water and ice clouds on tropical equilibrium states are investigated based on four two‐dimensional cloud‐resolving simulations imposed by a zero vertical velocity and constant zonal wind and sea surface temperature (SST). The model is integrated for 40 d to reach equilibrium states. Experiment CRFWI includes radiative effects of both water and ice clouds whereas experiment CRF00 excludes them. Experiments CRF0I and CRFW0 are identical to CRFWI except the radiative effects of water and ice clouds are excluded, respectively. CRF00 and CRFW0 produce similar cold and dry equilibrium states whereas CRFWI and CRF0I generate similar warm and humid equilibrium states. This indicates that water clouds may not have radiative effects on equilibrium states. The experiments without ice radiative effects (CRFW0 and CRF00) emit more IR radiation into space than the experiments with ice radiative effects (CRFWI and CRF0I) do. Colder air by more IR emission strengthens air‐sea flux exchanges and lowers air capacity to hold water vapor, resulting in larger surface evaporation and drier atmosphere. An increased surface evaporation is balanced with a stronger surface rain rate in the equilibrium domain mean water balance.
Contribution of ocean, fossil fuel, land biosphere, and biomass burning carbon fluxes to seasonal and interannual variability in atmospheric CO2
Authors: Nevison Cynthia D. , Mahowald Natalie M. , Doney Scott C. , Lima Ivan D. , van der Werf Guido R. , Randerson James T. , Baker David F. , Kasibhatla Prasad , McKinley Galen A.
Published: February 2008

Seasonal and interannual variability in atmospheric carbon dioxide (CO2) concentrations was simulated using fluxes from fossil fuel, ocean and terrestrial biogeochemical models, and a tracer transport model with time‐varying winds. The atmospheric CO2 variability resulting from these surface fluxes was compared to observations from 89 GLOBALVIEW monitoring stations. At northern hemisphere stations, the model simulations captured most of the observed seasonal cycle in atmospheric CO2, with the land tracer accounting for the majority of the signal. The ocean tracer was 3–6 months out of phase with the observed cycle at these stations and had a seasonal amplitude only ∼10% on average of observed. Model and observed interannual CO2 growth anomalies were only moderately well correlated in the northern hemisphere (R ∼ 0.4–0.8), and more poorly correlated in the southern hemisphere (R < 0.6). Land dominated the interannual variability (IAV) in the northern hemisphere, and biomass burning in particular accounted for much of the strong positive CO2 growth anomaly observed during the 1997–1998 El Niño event. The signals in atmospheric CO2 from the terrestrial biosphere extended throughout the southern hemisphere, but oceanic fluxes also exerted a strong influence there, accounting for roughly half of the IAV at many extratropical stations. However, the modeled ocean tracer was generally uncorrelated with observations in either hemisphere from 1979–2004, except during the weak El Niño/post‐Pinatubo period of the early 1990s. During that time, model results suggested that the ocean may have accounted for 20–25% of the observed slowdown in the atmospheric CO2 growth rate.
Properties of the transformation from the spherical wave expansion to the plane wave expansion
Authors: Cappellin Cecilia , Breinbjerg Olav , Frandsen Aksel
Published: February 2008

The transformation between the spherical wave expansion (SWE) and the plane wave expansion (PWE) is investigated with respect to a range of its fundamental properties. First, the transformation of individual spherical waves is studied in order to understand how these contribute to the different regions of the plane wave spectrum. Second, the number of spherical waves necessary to accurately determine the PWE over different regions of the spectral domain is investigated. Third, numerical aspects of the transformation are addressed.
Accuracy of USU‐GAIM specifications of foF2 and M(3000)F2 for a worldwide distribution of ionosonde locations
Authors: McNamara Leo F. , Baker Craig R. , Decker Dwight T.
Published: February 2008

The Utah State University (USU) Global Assimilation of Ionospheric Measurements (GAIM) model has replaced the Parameterized Real‐Time Ionospheric Specification Model (PRISM) for operational use at the Air Force Weather Agency (AFWA). Validation of the model by the Air Force Research Laboratory has therefore passed from the sanity checking stage to investigations of the accuracies and limitations of the model when it is used to generate Operational Space Environment Network Display (OpSEND) products. This paper presents the results of an extensive analysis of the errors in the USU‐GAIM specifications of the key ionogram characteristics foF2 and M(3000)F2 for 21 ionosonde locations distributed around the world, 9 in Australia and 12 in other countries, for September 2006. The ground‐truth observations of foF2 are manually scaled hourly values. The ground‐truth observations of M(3000)F2 are manually scaled hourly values for the Australian ionosondes, and filtered autoscaled values for the other 12 ionosondes. The analysis provides representative latitude‐dependent median errors for both characteristics, together with errors in the values of the maximum usable frequency for the standard 3000 km HF communications circuit. In general, GAIM performs well at all locations. The errors seem to be a function of the availability of data from nearby GPS TEC sites, the accuracy of the program's background ionosphere, and the validity of the assimilated TEC data, rather than of any limitations of the assimilation technique.
5‐Aza‐2′‐deoxycytidine suppresses human renal carcinoma cell growth in a xenograft model via up‐regulation of the connexin 32 gene
Authors: Hagiwara H , Sato H , Ohde Y , Takano Y , Seki T , Ariga T , Hokaiwado N , Asamoto M , Shirai T , Nagashima Y , Yano T
Published: February 2008

Background and purpose:

The connexin (Cx) 32 gene, a member of the gap junction gene family, acts as a tumour suppressor gene in human renal cell carcinoma (RCC) and is down‐regulated by the hypermethylation of CpG islands in a promoter region of the Cx gene. The current study investigated whether the restoration of Cx32 silenced by hypermethylation in RCC by a DNA demethylating agent could be an effective treatment against RCC.

Experimental approach:

Using nude mice bearing Caki‐1 cells (a human metastatic RCC cell line), the effects of 5‐aza‐2′‐deoxycytidine (5‐aza‐CdR), a DNA demethylase inhibitor, on Cx32 mRNA expression and tumour growth were examined by RT‐PCR, and by measuring tumour weight and volume. Cx32 expression in Caki‐1 tumours was inhibited by Cx32 short interfering (si) RNA, and the effect of siRNA on 5‐aza‐CdR‐dependent suppression of tumour growth in nude mice was evaluated.

Key results:

5‐aza‐CdR treatment inhibited the growth of Caki‐1 cells in nude mice by 70% and increased 7‐fold the level of Cx32 mRNA. The intratumour injection of Cx32 siRNA almost totally inhibited the expression of Cx32 mRNA and significantly reduced the suppression of tumour growth in 5‐aza‐CdR‐treated nude mice.

Conclusions and implications:

5‐aza‐CdR suppressed the growth of Caki‐1 tumours in a xenograft model, by restoring Cx32 expression. This finding suggests that treatment with 5‐aza‐CdR could be a new effective therapy against human metastatic RCC and that Cx32 could be a potential target for the treatment of RCC.

British Journal of Pharmacology (2008) 153, 1373–1381; doi:10.1038/bjp.2008.17; published online 11 February 2008
Gabapentin evoked changes in functional activity in nociceptive regions in the brain of the anaesthetized rat: an fMRI study
Authors: Governo R J M , Morris P G , Marsden C A , Chapman V
Published: February 2008

Background and purpose: Gabapentin (GBP; 1‐(aminomethyl)cyclohexane acetic acid) is used clinically in the treatment of pain. Nevertheless, the sites and mechanisms of action of GBP are poorly defined. Herein, the effects of GBP on brain activation have been studied.

Experimental approach: Changes in blood oxygen level dependent (BOLD) haemodynamic signal following intravenous infusion of GBP (equivalent to 30 mg kg−1 p.o., followed by 100 mg kg−1 p.o.), compared to saline control, were studied in isofluorane anaesthetized rats (n=8 per group). Effects of GBP on mean arterial blood pressure (MAP) were also recorded.

Results: Random effect analysis revealed that the lower dose of GBP produced significant (P<0.001) increases in BOLD signal intensity in several brain regions, including the thalamus and periaqueductal grey (PAG), compared to basal. This dose of GBP also produced significant (P<0.001) decreases in BOLD signal intensity in the amygdala and the entorhinal cortex. Increasing the dose of GBP (100 mg kg−1) produced significantly greater changes in BOLD signal intensity in several brain regions including the thalamus and PAG. MAP was not significantly altered by GBP, compared to saline.

Conclusions and implications: GBP had marked positive and negative effects on BOLD signal intensity in a number of brain regions in naïve rats. The activation of key areas involved in nociceptive processing indicate a supraspinal site of action of GBP and this may contribute to its well‐described analgesic effects in animal models of pain and clinical studies.

British Journal of Pharmacology (2008) 153, 1558–1567; doi:10.1038/bjp.2008.27; published online 11 February 2008
Contractile properties of the pig bladder mucosa in response to neurokinin A: a role for myofibroblasts?
Authors: Sadananda P , Chess‐Williams R , Burcher E
Published: February 2008

Background and purpose:

The bladder urothelium is now known to have active properties. Our aim was to investigate the contractile properties of the urinary mucosa in response to the tachykinin neurokinin A (NKA) and carbachol.

Experimental approach:

Discrete concentration–response curves for carbachol and NKA were obtained in matched strips of porcine detrusor, mucosa and intact bladder, suspended in organ baths. The effects of inhibitors and tachykinin receptor antagonists were studied on NKA‐mediated contractions in mucosal strips. Intact sections of bladder and experimental strips were processed for histology and immunohistochemistry.

Key results:

All types of strips contracted to both carbachol and NKA. Mucosal responses to NKA (pD2 7.2) were higher than those in intact strips and were inhibited by the NK2 receptor antagonist SR48968 (pKB 9.85) but not the NK1 receptor antagonist SR140333, tetrodotoxin or indomethacin. Immunostaining for smooth muscle actin and vimentin occurred under the urothelium and on blood vessels. Desmin immunostaining and histological studies showed only sparse smooth muscle to be present in the mucosal strips. Removal of smooth muscle remnants from mucosal strips did not alter the responses to NKA.

Conclusions and implications:

This study has shown both functional and histological evidence for contractile properties of the mucosa, distinct from the detrusor. Mucosal contractions to NKA appear to be directly mediated via NK2 receptors. The main cell type mediating mucosal contractions is suggested to be suburothelial myofibroblasts. Mucosal contractions may be important in vivo for matching the luminal surface area to bladder volume.

British Journal of Pharmacology (2008) 153, 1465–1473; doi:10.1038/bjp.2008.29; published online 11 February 2008
cAMP: fuel for extracellular adenosine formation?
Authors: Gödecke A
Published: February 2008

It is well known that cAMP, an important intracellular second messenger, is released from many cells upon adenylate cyclase stimulation. Cell surface bound phosphodiesterase together with ecto‐5′‐nucleotidase may convert the extracellular cAMP to adenosine, which may stimulate in a paracrine and/or autocrine manner cells expressing P1 receptors. In this issue of the British Journal of Pharmacology, Chiavegattiet al. demonstrate the existence of an extracellular cAMP‐adenosine cascade in skeletal muscle cells which suggests a link between adrenergic stimulation of contraction, elevated cAMP formation and release and exercise hyperaemia.

British Journal of Pharmacology(2008)153, 1087–1089; doi:10.1038/bjp.2008.7; published online 11 February 2008
Climate of Change Continues in Canada
Authors: Keon Jim
Published: February 2008

This paper provides a summary of recent changes to the legal, regulatory and policy environment affecting generic pharmaceutical manufacturers operating in the Canadian market. It provides a top-line overview of the Canadian pharmaceutical market in terms of generic market share by dollar value and prescriptions filled, and growth in both of those key indicators. This paper describes changes brought into force in October 2006 to regulations of Canada's Patent Act that attempt to limit ‘evergreening’ tactics employed by brand-name drug manufacturers to delay market entry of competing generic products, changes to regulations of Canada's Food and Drugs Act that provide new brand-name pharmaceutical products with eight years of data exclusivity (plus six-month paediatric exclusivity) and the response of the Canadian Generic Pharmaceutical Association (CGPA) to these regulatory changes. This paper also outlines changes to pricing and reimbursement rules for generic pharmaceutical products that are being implemented in the two largest Canadian jurisdictions of Ontario and Québec.
Rotational excitations in para-H2+para-H2 collisions: Full- and reduced-dimensional quantum wave packet studies comparing different potential energy surfaces
Authors: Otto Frank , Gatti Fabien , Meyer Hans-Dieter
Published: February 2008

We study the process of rotational excitation in the collisions of para-H2 with para-H2 by propagating wave packets with the multiconfiguration time-dependent Hartree (MCTDH) algorithm. Transition probabilities are then calculated by the method of Tannor and Weeks based on time-correlation functions. Calculations were carried out up to a total angular momentum of J=70 to compute integral cross sections up to 1.2eV in collision energy and thermal rate coefficients from 100to3000K. The process is studied on the full-dimensional potential energy surface of Boothroyd-Martin-Keogh-Peterson (BMKP) as well as on the rigid rotor surface of Diep and Johnson. We test the validity of the rigid rotor approximation by also considering two rigid rotor restrictions of the BMKP potential energy surface (PES). Additionally, we investigate a variant of the BMKP PES suggested by Pogrebnya and Clary [Chem. Phys. Lett. 363, 523 (2002)] with reduced anisotropy. We compare our results with previous theoretical data for the cross sections and with experimental data for the rate coefficients at low temperatures.
Binding energies and dissociation pathways in the aniline-Ar2 cation complex
Authors: Gu Quanli , Knee J. L.
Published: February 2008

Mass analyzed threshold ionization spectroscopy is used to measure the Ar binding energy for the cationic aniline-Ar (An+–Ar) and aniline-Ar2 (An+–Ar2) complexes. Since the experiments begin with the neutral species, photoexcitation creates the cations in the π-bonding configuration with the Ar located above the phenyl ring. The binding energy in this conformation of the An+–Ar complex is determined to be 495±15cm−1. Measurements of An+–Ar2 revealed the production of a lower energy dissociation product which is assigned to the An+–Ar H-bonding configuration. Combinations of measurements allow determination of the dissociation energy of this complex to be 640±20cm−1. The observation of a more stable H-bonded conformer is consistent with recent infrared experiments on An+–Ar complexes created by complexing An+ with Ar, rather than creation through the neutral complex. Calculations are presented which closely reproduce the binding energy of the π bound Ar but underestimate the stability of the H-bonded species.
Ferrocene-1,1′-dithiol as molecular wire between Ag electrodes: The role of surface defects
Authors: Bredow T. , Tegenkamp C. , Pfnür H. , Meyer J. , Maslyuk V. V. , Mertig I.
Published: February 2008

The interaction of ferrocene-1,1′-dithiol (FDT) with two parallel Ag(111) surfaces has been theoretically studied at density-functional level. The effect of surface defects on the energetic and electronic structure was investigated. The electronic transport properties are studied with the nonequilibrium Green’s function approach. The adsorption geometry has a strong effect on the electronic levels and conductivity. The presence of point defects strongly enhances the molecule-surface interaction but has a surprisingly small effect on the density of states near the Fermi energy. The FDT-surface bond is particularly strong near terraces or steps and leads to significant shifts of the molecular orbitals relative to the gas phase. For all considered defect types except the single adatom the electronic conductivity through the FDT molecule is decreased compared to adsorption on perfect surfaces.
Substrate-controlled growth and magnetism of nanosize Fe clusters on Pt
Authors: Skomski R. , Zhang J. , Sessi V. , Honolka J. , Kern K. , Enders A.
Published: February 2008

The growth and magnetism of nanosize Fe clusters on Pt and other metal surfaces are investigated. Fe clusters have been fabricated directly on the substrates by buffer layer assisted growth under ultrahigh vacuum conditions. The mean cluster diameter and the average cluster spacing were controlled by the Fe coverage and the buffer layer thickness. The enhanced magnetic anisotropy of such clusters of diameters between 0.5 and 10nm with respect to bulk is discussed. Interface anisotropy contributions are compared with direct dipolar cluster-cluster interaction and indirect interactions mediated by the substrate, including preasymptotic ferromagnetic interaction. It is found that this preasymptotic exchange is rather strong in exchange-enhanced substrates, such as Pt, but it decreases rapidly with increasing distance between clusters and becomes negligible for the experimental cluster spacings in this work. Except for clusters that nearly touch each other, the leading interaction contributions are RKKY-type exchange and magnetostatic dipole interactions.
Structural and magnetic roughness in a Co∕Ru multilayer patterned into a large scale hexagonal array
Authors: Kinane C. J. , Porter N. A. , Marrows C. H. , Hickey B. J. , Arena D. A. , Dvorak J. , Sirotkin E. , Ogrin F. Y. , Charlton T. , Langridge S.
Published: February 2008

Self-assembled arrays of nanospheres have been used to pattern a Co∕Pt multilayer into nanopillars. On top of this has been deposited a Co∕Ru multilayer, which is antiferromagnetically coupled. The nanopillars introduce a known structural and magnetic lateral modulation into the multilayer. Soft x-ray magnetic scattering was used to observe the interference patterned from the patterned substrate. This has allowed us to show how the magnetic roughness correlates with the structural roughness and obtain selective magnetometry of the various magnetic elements.
X-ray absorption and resonant Auger spectroscopy of O2 in the vicinity of the O 1s→σ* resonance: Experiment and theory
Authors: Feifel R. , Velkov Y. , Carravetta V. , Angeli C. , Cimiraglia R. , Sałek P. , Gel’mukhanov F. , Sorensen S. L. , Piancaśtelli M. N. , De Fanis A. , Okada K. , Kitajima M. , Tanaka T. , Tanaka H. , Ueda K.
Published: February 2008

We report on an experimental and theoretical investigation of x-ray absorption and resonant Auger electron spectra of gas phase O2 recorded in the vicinity of the O 1s→σ* excitation region. Our investigation shows that core excitation takes place in a region with multiple crossings of potential energy curves of the excited states. We find a complete breakdown of the diabatic picture for this part of the x-ray absorption spectrum, which allows us to assign an hitherto unexplained fine structure in this spectral region. The experimental Auger data reveal an extended vibrational progression, for the outermost singly ionized XΠg2 final state, which exhibits strong changes in spectral shape within a short range of photon energy detuning (0eV>Ω>−0.7eV). To explain the experimental resonant Auger electron spectra, we use a mixed adiabatic/diabatic picture selecting crossing points according to the strength of the electronic coupling. Reasonable agreement is found between experiment and theory even though the nonadiabatic couplings are neglected. The resonant Auger electron scattering, which is essentially due to decay from dissociative core-excited states, is accompanied by strong lifetime-vibrational and intermediate electronic state interferences as well as an interference with the direct photoionization channel. The overall agreement between the experimental Auger spectra and the calculated spectra supports the mixed diabatic/adiabatic picture.
Spin-orbit precession damping in transition metal ferromagnets (invited)
Authors: Gilmore K. , Idzerda Y. U. , Stiles M. D.
Published: February 2008

We provide a simple explanation, based on an effective field, for the precession damping rate due to the spin-orbit interaction. Previous effective field treatments of spin-orbit damping include only variations of the state energies with respect to the magnetization direction, an effect referred to as the breathing Fermi surface. Treating the interaction of the rotating spins with the orbits as a perturbation, we include also changes in the state populations in the effective field. In order to investigate the quantitative differences between the damping rates of iron, cobalt, and nickel, we compute the dependence of the damping rate on the density of states and the spin-orbit parameter. There is a strong correlation between the density of states and the damping rate. The intraband terms of the damping rate depend on the spin-orbit parameter cubed, while the interband terms are proportional to the spin-orbit parameter squared. However, the spectrum of band spacings is also an important quantity and does not appear to depend in a simple way on material parameters.