215 research outputs found

    Methyl chloride as a tracer of tropical tropospheric air in the lowermost stratosphere inferred from IAGOS-CARIBIC passenger aircraft measurements

    Get PDF
    We present variations of methyl chloride (CH3Cl) and nitrous oxide (N2O) in the lowermost stratosphere (LMS) obtained from air samples collected by the In-service Aircraft for a Global Observing System-Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container (IAGOS-CARIBIC) passenger aircraft observatory for the period 2008-2012. To correct for the temporal increase of atmospheric N2O, the CARIBIC N2O data are expressed as deviations from the long-term trend at the northern hemispheric baseline station Mauna Loa, Hawaii (Delta N2O).Delta N2O undergoes a pronounced seasonal variation in the LMS with a minimum in spring. The amplitude increases going deeper in the LMS (up to potential temperature of 40 K above the thermal tropopause), as a result of the seasonally varying subsidence of air from the stratospheric overworld. Seasonal variation of CH3Cl above the tropopause is similar in phase to that of Delta N2O. Significant correlations are found between CH3Cl and Delta N2O in the LMS from winter to early summer, both being affected by mixing between stratospheric air and upper tropospheric air. This correlation, however, disappears in late summer to autumn. The slope of the CH3Cl-Delta N2O correlation observed in the LMS allows us to determine the stratospheric lifetime of CH3Cl to be 35 +/- 7 years. Finally, we examine the partitioning of stratospheric air and tropical/extratropical tropospheric air in the LMS based on a mass balance approach using Delta N2O and CH3Cl. This analysis clearly indicates efficient inflow of tropical tropospheric air into the LMS in summer and demonstrates the usefulness of CH3Cl as a tracer of tropical tropospheric air

    Pollution events observed during CARIBIC flights in the upper troposphere between South China and the Philippines

    Get PDF
    A strong pollution episode in the upper troposphere between South China and the Philippines was observed during CARIBIC flights in April 2007. Five pollution events were observed, where enhancements in aerosol and trace gas concentrations including CO, CO2_2, CH4_4, non-methane hydrocarbons (NMHCs) and halocarbons were observed along the flight tracks during four sequential flights. The importance of the contribution of biomass/biofuel burning was investigated using chemical tracers, emission factor analysis, back-trajectory analysis and satellite images. The Indochinese peninsula was identified as the probable source region of biomass/biofuel burning. However, enhancements in the urban/industrial tracer C2_2Cl4_4 during the events also indicate a substantial contribution from urban anthropogenic emissions. An estimation of the contribution of fossil fuel versus biomass/biofuel to the CO enhancement was made, indicating a biomass/biofuel burning contribution of ~54 to ~92% of the observed CO enhancements. Biomass/biofuel burning was found to be the most important source category during the sampling period

    Internet of things–Enabled technologies as an intervention for childhood obesity: A systematic review

    Get PDF
    Childhood obesity is one of the most serious public health challenges of the 21st century, with consequences lasting into adulthood. Internet of Things (IoT)-enabled devices have been studied and deployed for monitoring and tracking diet and physical activity of children and adolescents as well as a means of providing remote, ongoing support to children and their families. This review aimed to identify and understand current advances in the feasibility, system designs, and effectiveness of IoT-enabled devices to support weight management in children. We searched Medline, PubMed, Web of Science, Scopus, ProQuest Central and the IEEE Xplore Digital Library for studies published after 2010 using a combination of keywords and subject headings related to health activity tracking, weight management, youth and Internet of Things. The screening process and risk of bias assessment were conducted in accordance with a previously published protocol. Quantitative analysis was conducted for IoT-architecture related findings and qualitative analysis was conducted for effectiveness-related measures. Twenty-three full studies are included in this systematic review. The most used devices were smartphone/mobile apps (78.3%) and physical activity data (65.2%) from accelerometers (56.5%) were the most commonly tracked data. Only one study embarked on machine learning and deep learning methods in the service layer. Adherence to IoT-based approaches was low but game-based IoT solutions have shown better effectiveness and could play a pivotal role in childhood obesity interventions. Researcher-reported effectiveness measures vary greatly amongst studies, highlighting the importance for improved development and use of standardised digital health evaluation frameworks.</jats:p

    Characterization of non-methane hydrocarbons in Asian summer monsoon outflow observed by the CARIBIC aircraft

    Get PDF
    Between April and December 2008 the CARIBIC commercial aircraft conducted monthly measurement flights between Frankfurt, Germany and Chennai, India. These flights covered the period of the Asian summer monsoon (June–September), during which enhancements in a number of atmospheric species were observed in the upper troposphere over southwestern Asia. In addition to in situ measurements of trace gases and aerosols, whole air samples were collected during the flights, and these were subsequently analyzed for a suite of trace gases that included a number of C2–C8 non-methane hydrocarbons. Non-methane hydrocarbons are relatively short-lived compounds and the large enhancements in their mixing ratios in the upper troposphere over southwestern Asia during the monsoon, sometimes more than double their spring and fall means, provides qualitative evidence for the influence of convectively uplifted boundary layer air. The particularly large enhancements of the combustion tracers benzene and ethyne, along with the similarity of their ratios with carbon monoxide and emission ratios from the burning of household biofuels, indicate a strong influence of biofuel burning to NMHC emissions in this region. Conversely, the ratios of ethane and propane to carbon monoxide, along with the ratio between i-butane and n-butane, indicate a significant source of these compounds from the use of fossil fuels, and comparison to previous campaigns suggests that this source could be increasing. Photochemical aging patterns of NMHCs showed that the CARIBIC samples were collected in two distinctly different regions of the monsoon circulation: a southern region where air masses had been recently influenced by low level contact and a northern region, where air parcels had spent substantial time in transit in the upper troposphere before being probed. Estimates of age using ratios of individual NMHCs have ranges of 3–6 days in the south and 9–12 days in the north

    Real-World Evaluation of the Feasibility, Acceptability and Safety of a Remote, Self-Management Parkinson’s Disease Care Pathway: A Healthcare Improvement Initiative

    Get PDF
    Background: There is significant unmet need for effective and efficiently delivered care for people with Parkinson’s disease (PwP). We undertook a service improvement initiative to co-develop and implement a new care pathway, Home Based Care (HBC), based on supported self-management, remote monitoring and the ability to trigger a healthcare contact when needed. Objective: To evaluate feasibility, acceptability and safety of Home Based Care. Methods: We evaluated data from the first 100 patients on HBC for 6 months. Patient monitoring, performed at baseline and 6-monthly, comprised motor (MDS-UPDRS II and accelerometer), non-motor (NMSQ, PDSS-2, HADS) and quality of life (PDQ) measures. Care quality was audited against Parkinson’s UK national audit standards. Process measures captured feasibility. Acceptability was assessed using a mixed-methods approach comprising questionnaires and semi-structured interviews. Results: Between October 2019 and January 2021, 108 PwP were enrolled onto HBC, with data from 100 being available at 6 months. Over 90% of all questionnaires were returned, 97% were complete or had &lt; 3 missing items. Reporting and communications occurred within agreed timeframes. Compared with baseline, after 6m on HBC, PD symptoms were stable; more PwP felt listened to (90% vs. 79%) and able to seek help (79% vs. 68%). HBC met 93% of national audit criteria. Key themes from the interviews included autonomy and empowerment. Conclusions: We have demonstrated acceptability, feasibility and safety of our novel remotely delivered Parkinson’s care pathway. Ensuring scalability will widen its reach and realize its benefits for underserved communities, enabling formal comparisons with standard care and cost-effectiveness evaluation

    Disentangling Income Inequality and the Redistributive Effect of Social Transfers and Taxes in 36 LIS Countries

    Full text link

    Mesenchymal Stem Cells Induce T-Cell Tolerance and Protect the Preterm Brain after Global Hypoxia-Ischemia

    Get PDF
    Hypoxic-ischemic encephalopathy (HIE) in preterm infants is a severe disease for which no curative treatment is available. Cerebral inflammation and invasion of activated peripheral immune cells have been shown to play a pivotal role in the etiology of white matter injury, which is the clinical hallmark of HIE in preterm infants. The objective of this study was to assess the neuroprotective and anti-inflammatory effects of intravenously delivered mesenchymal stem cells (MSC) in an ovine model of HIE. In this translational animal model, global hypoxia-ischemia (HI) was induced in instrumented preterm sheep by transient umbilical cord occlusion, which closely mimics the clinical insult. Intravenous administration of 2 x 106MSC/kg reduced microglial proliferation, diminished loss of oligodendrocytes and reduced demyelination, as determined by histology and Diffusion Tensor Imaging (DTI), in the preterm brain after global HI. These anti-inflammatory and neuroprotective effects of MSC were paralleled by reduced electrographic seizure activity in the ischemic preterm brain. Furthermore, we showed that MSC induced persistent peripheral T-cell tolerance in vivo and reduced invasion of T-cells into the preterm brain following global HI. These findings show in a preclinical animal model that intravenously administered MSC reduced cerebral inflammation, protected against white matter injury and established functional improvement in the preterm brain following global HI. Moreover, we provide evidence that induction of T-cell tolerance by MSC might play an important role in the neuroprotective effects of MSC in HIE. This is the first study to describe a marked neuroprotective effect of MSC in a translational animal model of HIE
    • …
    corecore