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Up to a third of ex-preterm infants flying near term exhibit pulse oxygen saturation (SpO2) of less than 85% during air travel. A hypoxia challenge test (HCT) is recommended to evaluate the requirement for in-flight supplemental O2. The validity of the HCT in healthy, term infants has not been reported. This study aimed to characterise the in-flight hypoxia response and the accuracy of the HCT to predict this response in healthy, term infants in the first year of life. Infants (n=24: (15 male)) underwent a HCT prior to commercial air travel during which parents monitored SpO2. Thirty-two flights were undertaken with six infants completing multiple flights. The median in-flight SpO2 nadir was 87% and significantly lower than the HCT SpO2 nadir (92%: p<0.001). Infants on seven flights recorded SpO2<85% with one infant recording a HCT with a SpO2 less than 85%. There was marked variability in the in-flight SpO2 in the six infants who undertook multiple flights, and for three of these infants, the SpO2 nadir was both above and below 85%. We report that in healthy term infants an in-flight SpO2 below 85% is common and can vary considerably between flights and that the HCT poorly predicts the risk of in-flight hypoxia (SpO2<85%). As it is common for healthy term infants to have SpO2 less than 85% during air travel further research is needed to clarify whether this is an appropriate cut-off in this age group.

INTRODUCTION: Approximately 10-15% of term babies may require admission to neonatal special care units. This level of care is frequently an unexpected event for parents. AIMS: To review the frequency and obstetric risk factors associated with the admission of term neonates to a tertiary hospital special care unit (SCN). MATERIALS AND METHODS: All babies born >/=37-weeks gestation admitted to the SCN at King Edward Memorial Hospital between 2004 and 2006 were identified from the institutional maternity and neonatal databases. Maternal and obstetric factors were reviewed to identify potential predictors of admission to the SCN. RESULTS: During the study period, 1671 term neonates born to 1624 women were admitted to the SCN (14.4% of term deliveries). Neonatal intensive care unit admissions accounted for 10.6% of the term admissions. The most common reasons for SCN admission were respiratory complications (n = 421, 25.2%), observation postresuscitation (n = 402, 24.1%) and hypoglycaemia (n = 152, 9.1%). Elective caesarean delivery was significantly associated with admission to the special care unit for respiratory complications compared with all other delivery modes (37 vs 23%, P < 0.001), particularly if the birth occurred at <39-weeks gestation (38 vs 24%, P < 0.001). CONCLUSIONS: In our population of women delivering at a tertiary maternity facility, approximately 1:8 term babies were admitted to the neonatal special care unit. Elective caesarean delivery was associated with a significant risk of admission for respiratory complications compared with other birth modes, especially when <39-weeks gestation.

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During the International Polar Year (IPY), comprehensive observational research programs were undertaken to increase our understanding of the Canadian polar cryosphere response to a changing climate. Cryospheric components considered were snow, permafrost, sea ice, freshwater ice, glaciers and ice shelves. Enhancement of conventional observing systems and retrieval algorithms for satellite measurements facilitated development of a snapshot of current cryospheric conditions, providing a baseline against which future change can be assessed. Key findings include: 1. surface air temperatures across the Canadian Arctic exhibit a warming trend in all seasons over the past 40 years. A consistent pan-cryospheric response to these warming temperatures is evident through the analysis of multi-decadal datasets; 2. in recent years (including the IPY period) a higher rate of change was observed compared to previous decades including warming permafrost, reduction in snow cover extent and duration, reduction in summer sea ice extent, increased mass loss from glaciers, and thinning and break-up of the remaining Canadian ice shelves. These changes illustrate both a reduction in the spatial extent and mass of the cryosphere and an increase in the temporal persistence of melt related parameters. The observed changes in the cryosphere have important implications for human activity including the close ties of northerners to the land, access to northern regions for natural resource development, and the integrity of northern infrastructure.

Modern Methods of Construction (MMC), Offsite Manufacturing (OSM), and Offsite Production (OSP) are all umbrella terms cited as being possible panacea solutions for addressing time, quality and cost concerns often associated with ‘traditional’ construction. In this respect, these issues have been on the agenda for a while now, with no viable business process models or solutions [cf. traditional to manufacturing/installation] being proffered or promoted as a meaningful ways forward. In an attempt to address this, a focus group workshop was established with domain experts to explore industry uptake and multidisciplinary expectations and priorities within the AEC sector. This paper presents findings from this session, covering the relationships between people, process and technology - mapped against the three core silos of Design, Manufacturing and Construction. Research areas investigated em- braced several integral issues, from information and process flows, through to production, risk, and market drivers and inhibitors. Research findings identified a high demand for technology adoption in the design and construction remits, and a need to change traditional thinking across the whole supply chain. Core findings and priorities are presented for industry reflection in order to shape the future research agenda in this area.

The influence of whole body sitting posture on cervico-thoracic posture, mechanical load and extensor muscle activity was examined in 23 asymptomatic adults. Cervical and upper thoracic extensor muscle activity measured in guided slouched and lumbo-pelvic neutral postures was normalised to that measured in a self-selected habitual posture. Head and neck posture and gravitational load moment measurements were obtained in each posture. Sagittal head translation, upper cervical extension and load moment were significantly greater in the slouched posture (p < 0.001). Contrasting patterns of cervical and thoracic extensor activity were observed in the slouched and neutral postures, with cervical extensor activity 40% higher in the slouched posture (p < 0.0001). Thoracic extensor activity was significantly higher in the lumbo-pelvic neutral posture than the habitual posture (p = 0.002). The significant changes in extensor muscle activity with postural modification appear to be induced by the associated change in mechanical load moment of the head.

Reproductive toxicity data for the antimalarial drug piperaquine (PQ) were obtained in pregnant mice (F(0)) and their offspring (F(1) and F(2)). PQ phosphate (0-300 mg/kg/day) was given to pregnant Swiss mice from gestational days 14-18. Two F(1) pups from each litter (one male and one female) proceeded to maturity and were mated within dose groups. Biochemical and haematological indices were determined, and liver and kidney histopathology was assessed in F(1) and F(2) mice at 4 weeks. There were no significant dose-related adverse effects, but leucocytes were mildly elevated (F(1) and F(2) mice) and serum albumin was reduced (F(1) only) in the 300 mg/kg/day group. Low plasma PQ concentrations were detected in F(1) mice at 4 and 8 weeks. Although we found no significant PQ toxicity, clinical data are lacking and monitoring of women and their infants for biochemical and haematological adverse effects is recommended when PQ is used in pregnancy.

The basal regions of continental ice sheets are gaps in our current understanding of the Earth's biosphere and biogeochemical cycles. We draw on existing and new chemical data sets for subglacial meltwaters to provide the first comprehensive assessment of sub-ice sheet biogeochemical weathering. We show that size of the ice mass is a critical control on the balance of chemical weathering processes and that microbial activity is ubiquitous in driving dissolution. Carbonate dissolution fueled by sulfide oxidation and microbial CO2 dominate beneath small valley glaciers. Prolonged meltwater residence times and greater isolation characteristic of ice sheets lead to the development of anoxia and enhanced silicate dissolution due to calcite saturation. We show that sub-ice sheet environments are highly geochemically reactive and should be considered in regional and global solute budgets. For example, calculated solute fluxes from Antarctica (72-130 t yr(-1)) are the same order of magnitude as those from some of the world's largest rivers and rates of chemical weathering (10-17 t km(-2) yr(-1)) are high for the annual specific discharge (2.3-4.1 x 10(-3) m). Our model of chemical weathering dynamics provides important information on subglacial biodiversity and global biogeochemical cycles and may be used to design strategies for the first sampling of Antarctic Subglacial Lakes and other sub-ice sheet environments for the next decade.

Beak and feather disease virus (BFDV) is a significant pathogen of wild Australasian and African psittacine birds. We assessed the immunogenicity of recombinant BFDV capsid (recBFDVcap) to protect against the development of psittacine beak and feather disease (PBFD). Long-billed corellas (Cacatua tenuirostris) (n=13) received (by injection) 1 ml vaccine containing 10 μg recBFDVcap on day 0 and 0.4 ml vaccine containing 66.8 μg recBFDVcap on day 11. All vaccinated corellas and five non-vaccinated control corellas were given 0.4 ml BFDV suspension [titre=log2 12 haemagglutination units (HAU) 50 μl-1] intramuscularly and 0.1 ml orally 16 days after booster vaccination. Blood was collected during the vaccination period and blood and feathers were collected after BFDV administration. Testing of blood samples included BFDV DNA detection by PCR and quantitative PCR (qPCR) as well as antibody detection by haemagglutination inhibition (HI) and on feather samples, BFDV DNA and antigen was detected by haemagglutination (HA) and qPCR. Four of 97 blood samples collected from vaccinated birds after virus challenge tested positive by PCR, whereas 17 of 35 samples taken from non-vaccinated control corellas tested positive. Vaccinated birds did not develop feather lesions, had only transient PCR-detectable viraemia and had no evidence of persistent infection 270 days post-challenge using PCR, histopathology and immunohistochemistry. Non-vaccinated control corellas developed transient feather lesions and had PCR, HI and HA test results consistent with PBFD. They were BFDV PCR-positive for up to 41 days post-challenge and qPCR demonstrated reduced virus replication in vaccinated birds compared with non-vaccinated control birds.

PCR-based assays for the detection of BFDV DNA are in widespread use throughout the world. Quantitative real-time PCR assays are extremely sensitive and have the advantages over standard PCR assays that they do not require post-reaction processing to visualise PCR products and can quantify the amount of DNA present in a sample. This study describes a quantitative real-time PCR assay for the detection of BFDV DNA, using primers designed to amplify a conserved 81 bp fragment of ORFV1 and SYTO9, a fluorescent intercalating dye. A synthetic oligonucleotide was used to make standard curves for the quantitation of viral load in blood and feather preparations. The assay was very sensitive, with a detection limit of 50 copies/μL. The assay was developed using DNA extracts from the feathers of 10 different species of birds which had tested BFDV-positive previously and was validated with blood and feather samples from corellas vaccinated with an experimental BFDV vaccine, then challenged with live virus. Viral DNA was detected consistently in the blood of all control (non-vaccinated) birds and in some vaccinated birds. Contamination of the environment with feather dander from BFDV-infected birds meant that feather preparations used for the haemagglutination assay were unreliable for the detection and quantitation of viral excretion. Nonetheless, the assay should prove to be a useful and sensitive test for the detection of viral DNA in a range of samples.

The hematological characteristics of juvenile long-billed corellas (Cacatua tenurostris), with or without prior administration of a psittacine beak and feather disease vaccine, were studied for 97 days after experimental infection with beak and feather disease virus (BFDV). It was found that the pre-challenge hematological values were similar between vaccinated and non-vaccinated corellas. Most pre-challenge parameters were comparable to previously reported values of other cockatoos and psittacine birds. Significant differences were seen in both groups when comparing pre-challenge values with post-challenge values for total and differential leukocyte concentrations, but packed cell volume and total serum protein were not significantly affected by BFDV challenge.

Currently, the only diagnostic test available routinely for the sero-diagnosis of BFDV is the haemagglutination-inhibition (HI) assay. This test, whilst useful and applicable to samples from a wide range of psittacine birds, is not an ideal assay; it requires erythrocytes from live animals, virus purified from the feathers of infected birds and polyclonal antibody preparations in order to perform the assay. Variations in these reagents make consistency between tests difficult to achieve, underscoring the need for a new test with standardised reagents for the sero-diagnosis of BFDV infection which has led to the development of an antibody response. The methods used to develop a novel "blocking" (or "competitive") ELISA (bELISA) for the detection of anti-BFDV antibodies in psittacine sera are presented in this paper. The assay was developed using a baculovirus-expressed recombinant BFDV capsid protein and a newly developed monoclonal antibody raised against this protein. The assay was then validated with 160 samples from eastern long-billed corellas (Cacatua tenuiostris) vaccinated with the recombinant capsid protein and challenged with live virus and samples from 82 cockatiels known to be HI negative. The bELISA described in this study is a sensitive and specific diagnostic test and should have wide application for the sero-diagnosis of BFDV.

Based on experimental magnetic-field-dependent neutron scattering data, we have calculated the autocorrelation function of the spin misalignment of nanocrystalline 160gadolinium. The analysis suggests the existence of two characteristic length scales in the spin system: the smaller one is about 5 nm and is attributed to the defect cores of the grain boundaries, whereas the larger length scale is of the order of the average crystallite size D = 21 nm and presumably describes the response of the magnetization to the magnetic anisotropy field of the individual crystallites.

We report magnetization and magnetic neutron scattering measurements on nanocrystalline Fe which was prepared by means of the inert-gas condensation technique. Depending on the compaction pressure applied during the synthesis procedure (0.5–1.8 GPa), the resulting Fe samples contain porosity with volume fractions between about 20–35%. We provide evidence that the spin disorder which is associated with porosity has a strong influence on magnetic properties, and it gives rise to a characteristic clover-leaf–shaped angular anisotropy in the elastic-magnetic-scattering cross-section.

To examine change in physical fitness and body composition after a military deployment to Afghanistan. Methods: one hundred and ten infantry soldiers were measured before and after a 9-month deployment to Afghanistan for Operation Enduring Freedom. Measurements included treadmill peak oxygen uptake (peak VO2), lifting strength, medicine ball put, vertical jump, and body composition estimated via dual-energy x-ray absorptiometry (percent body fat), absolute body fat, fat-free mass, bone mineral content, and bone mineral density. Results: There were significant decreases (P<0.01) in peak VO2 (-4.5%), medicine ball put(-4.9% body mass {-1.9%}, and fat-free mass{-3.5 %}, wheras percent body fat increased from 17.7% to 19.6%., Pub. in Medicine and Science in Sport and Exercise, v40 n9, p1687-1692, 2008.

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Psittacine beak and feather disease is known to occur in a wide range of psittacine species; however, there are no scientific or credible anecdotal reports of psittacine beak and feather disease occurring in the cockatiel (Nymphicus hollandicus) despite it being one of the world's most commonly kept companion bird species. Consequently, this has resulted in speculation that the species may have some innate resistance to beak and feather disease virus (BFDV) infection. To investigate this hypothesis we conducted a survey of cockatiels (n=88) at commercial aviaries to investigate whether BFDV infection occurs in cockatiels, and found that all birds were virus-free by polymerase chain reaction and haemagglutination assay and had no detectable antibody titre by haemagglutination-inhibition assay. In addition to this, we sequenced the genome of two BFDV isolates obtained from diseased cockatiel feathers and performed cross-reactivity assays using virus eluted from these feathers and sera from naturally immune psittacine birds. Serological cross-reactivity results and phylogenetic analysis of the nucleotide sequences indicated that the cockatiel virus isolates were serologically and genetically different to other BFDV isolates. This is the first paper to report evidence of an antigenically distinct BFDV in psittacine birds.

The development of diagnostic assays for detecting beak and feather disease virus (BFDV) has traditionally been hampered by the difficulty associated with producing suitable reagents, namely purified virus and polyclonal antibodies. In an effort to develop a consistent and standardised source of antibody, amonoclonalantibody to are combinant BFDV capsid protein has been developed and its use in western blotting, immunohistochemistry (IHC), ELISA and haemagglutination-inhibition (HI) assays characterised. The antibody was specific for both the recombinant BFDV capsid protein and the whole virus and had similar optimal titres when used in western blotting and IHC. The antibody also had HI activity and detected BFDV virus from three genera of psittacine birds, including the recently described cockatiel BFDV isolate. The monoclonal antibody should have widespread application in both research and the development of diagnostic assays for BFDV.

We investigate the utility of a new, self-similar pressure profile for fitting Sunyaev-Zel'dovich (SZ) effect observations of galaxy clusters. Current SZ imaging instruments - such as the Sunyaev-Zel'dovich Array (SZA) - are capable of probing clusters over a large range in physical scale. A model is therefore required that can accurately describe a cluster's pressure profile over a broad range of radii, from the core of the cluster out to a significant fraction of the virial radius. In the analysis presented here, we fit a radial pressure profile derived from simulations and detailed X-ray analysis of relaxed clusters to SZA observations of three clusters with exceptionally high quality X-ray data: A1835, A1914, and CL J1226.9+3332. From the joint analysis of the SZ and X-ray data, we derive physical properties such as gas mass, total mass, gas fraction and the intrinsic, integrated Compton y-parameter. We find that parameters derived from the joint fit to the SZ and X-ray data agree well with a detailed, independent X-ray-only analysis of the same clusters. In particular, we find that, when combined with X-ray imaging data, this new pressure profile yields an independent electron radial temperature profile that is in good agreement with spectroscopic X-ray measurements., Comment: 28 pages, 6 figures, accepted by ApJ for publication (probably April 2009)

We report on magnetic-field–dependent small-angle neutron scattering (SANS) experiments on nanocrystalline inert-gas condensed bulk Gd, which was synthesized using the low-capturing isotope 160Gd. The angular dependency of the scattering cross-section is in very good agreement with recent theoretical predictions. Rather unexpected for this type of material, we observe a "clover-leaf–shaped" anisotropy in the SANS signal, the origin of which is attributed to the existence of longitudinal magnetization fluctuations associated with atomic site disorder and modified coupling inside the defect cores of grain boundaries.