2,259 research outputs found
Zero-G Workstation Design
Zero-g workstations were designed throughout manned spaceflight, based on different criteria and requirements for different programs. The history of design of these workstations is presented along with a thorough evaluation of selected Skylab workstations (the best zero-g experience available on the subject). The results were applied to on-going and future programs, with special emphasis on the correlation of neutral body posture in zero-g to workstation design. Where selected samples of shuttle orbiter workstations are shown as currently designed and compared to experience gained during prior programs in terms of man machine interface design, the evaluations were done in a generic sense to show the methods of applying evaluative techniques
COMPASS: a 2.6m telescope for CMBR polarization studies
COMPASS (COsmic Microwave Polarization at Small Scale) is an experiment devoted to measuring the polarization of the CMBR. Its design and characteristics are presented
The effects of anaesthesia on cell death in a porcine model of neonatal hypoxic-ischaemic brain injury
Background: Hypothermia is neuroprotective after neonatal hypoxic-ischaemic brain injury. However, systemic cooling to hypothermic temperatures is a stressor and may reduce neuroprotection in awake pigs. We compared two experiments of global hypoxic-ischaemic injury in newborn pigs, in which one group received propofol–remifentanil and the other remained awake during post-insult hypothermia treatment.
Methods: In both studies, newborn pigs were anaesthetised using halothane during a 45-min global hypoxic-ischaemic insult induced by reducing Fio2 and graded hypotension until a low-voltage <7 μV electroencephalogram was achieved. On reoxygenation, the pigs were randomly allocated to receive 24 h of normothermia or hypothermia. In the first study (n=18) anaesthesia was discontinued and the pigs' tracheas were extubated. In the second study (n=14) anaesthesia was continued using propofol and remifentanil. Brain injury was assessed after 72 h by classical global histopathology, Purkinje cell count, and apoptotic cell counts in the hippocampus and cerebellum.
Results: Global injury was nearly 10-fold greater in the awake group compared with the anaesthetised group (P=0.021). Hypothermia was neuroprotective in the anaesthetised pigs but not the awake pigs. In the hippocampus, the density of cleaved caspase-3-positive cells was increased in awake compared with anaesthetised pigs in normothermia. In the cerebellum, Purkinje cell density was reduced in the awake pigs irrespective of treatment, and the number of cleaved caspase-3-positive Purkinje cells was greatly increased in hypothermic awake pigs. We detected no difference in cleaved caspase-3 in the granular cell layer or microglial reactivity across the groups.
Conclusions: Our study provides novel insights into the significance of anaesthesia/sedation during hypothermia for achieving optimal neuroprotection
Breaking the Redshift Deadlock - I: Constraining the star formation history of galaxies with sub-millimetre photometric redshifts
Future extragalactic sub-millimetre and millimetre surveys have the potential
to provide a sensitive census of the level of obscured star formation in
galaxies at all redshifts. While in general there is good agreement between the
source counts from existing SCUBA (850um) and MAMBO (1.25mm) surveys of
different depths and areas, it remains difficult to determine the redshift
distribution and bolometric luminosities of the sub-millimetre and millimetre
galaxy population. This is principally due to the ambiguity in identifying an
individual sub-millimetre source with its optical, IR or radio counterpart
which, in turn, prevents a confident measurement of the spectroscopic redshift.
Additionally, the lack of data measuring the rest-frame FIR spectral peak of
the sub-millimetre galaxies gives rise to poor constraints on their rest-frame
FIR luminosities and star formation rates. In this paper we describe
Monte-Carlo simulations of ground-based, balloon-borne and satellite
sub-millimetre surveys that demonstrate how the rest-frame FIR-sub-millimetre
spectral energy distributions (250-850um) can be used to derive photometric
redshifts with an r.m.s accuracy of +/- 0.4 over the range 0 < z < 6. This
opportunity to break the redshift deadlock will provide an estimate of the
global star formation history for luminous optically-obscured galaxies [L(FIR)
> 3 x 10^12 Lsun] with an accuracy of 20 per cent.Comment: 14 pages, 22 figures, submitted to MNRAS, replaced with accepted
versio
CFS/ME OG AKTIVITETSAVPASNING En litteraturstudie om mennesker med CFS/ME sine opplevelser av aktivitetsavpasning (pacing)
Problemstilling: “Hvordan oppleves aktivitetsavpasning (Pacing) som en mestringsstrategi
for personer med mild-moderat CFS/ME?”.
Formål: Formålet med denne oppgaven er å undersøke hva forskning sier om pasienter med
Chronic fatigue syndrome/Myalgic encephalomyelitis (CFS/ME) sine opplevelser knyttet til
aktivitetsavpasning.
Metode: Foretatt systematisk litteratursøk for å finne kvalitative studier som viser hvilke
opplevelser mennesker med CFS/ME har til aktivitetsavpasning. De vitenskapelige artiklene
som blir brukt i litteraturgjennomgangen er presentert i ulike databaser: EBSCO (Academic
search elite), Pubmed og EMBASE. Aveyards tematiske analysemodell beskrevet i Thidemann
ble benyttet for å analysere resultatene.
Resultat: Aktivitetsavpasning ble i stor grad ansett som positivt, hvor denne
mestringsstrategien ble brukt for å forhindre forverring av symptomer. Det gav et endret
aktivitetsmønster, bevissthet på gjennomførelse av aktiviteter, energinivå og å få en positiv
tankegang, samt motivasjon. Samtidig finnes det også utfordringer for å kunne ta i bruk
aktivitetsavpasning som, symptomer, manglende kontroll, følelser og personlige egenskaper.
Konklusjon: Gjennom utførelsen av denne litteraturstudien kommer det frem at mennesker
med CFS/ME opplever aktivitetsavpasning som en nyttig mestringsstrategi. Det er videre
behov for nyere og større studier som omhandler erfaringer, men også studier som viser
effekt. Det er nødvendig for å kunne gi anbefalinger i videre praksis.publishedVersio
Morphine and fentanyl exposure during therapeutic hypothermia does not impair neurodevelopment
Background
Hypothermia-treated and intubated infants with moderate or severe hypoxic-ischemic encephalopathy (HIE) usually receive morphine for sedation and analgesia (SA) during therapeutic hypothermia (TH) and endotracheal ventilation. Altered drug pharmacokinetics in this population increases the risk of drug accumulation. Opioids are neurotoxic in preterm infants. In term infants undergoing TH, the long-term effects of morphine exposure are unknown. We examined the effect of opioid administration during TH on neurodevelopmental outcome and time to extubation after sedation ended.
Methods
In this prospectively collected population-based cohort of 282 infants with HIE treated with TH (2007–2017), the cumulative opioid dose of morphine and equipotent fentanyl (10–60 µg/kg/h) administered during the first week of life was calculated. Clinical outcomes and concomitant medications were also collected. Of 258 survivors, 229 underwent Bayley-3 neurodevelopmental assessments of cognition, language and motor function at 18–24 months. Multivariate stepwise linear regression analysis was used to examine the relation between cumulative opioid dose and Bayley-3 scores. Three severity-groups (mild-moderate-severe) were stratified by early (<6 h) amplitude-integrated electroencephalography (aEEG) patterns.
Findings
The cumulative dose of opioid administered as SA during TH was median (IQR) 2121 µg/kg (1343, 2741). Time to extubation was independent of SA dose (p > 0.2). There was no significant association between cumulative SA dose and any of the Bayley-3 domains when analysing the entire cohort or any of the aEEG severity groups.
Interpretation
Higher cumulative opioid doses in TH-treated infants with HIE was not associated with worse Bayley-3 scores at 18–24 months of age.
Funding
The Bristol cooling program was funded by the Children's Medical Research Charity SPARKS managing donations for our research from the UK and US, the UK Moulton Foundation, the Lærdal Foundation for Acute Medicine in Norway and the Norwegian Research Council (JKG)
An Exploratory Study Of Student Satisfaction With University Web Page Design
This exploratory study evaluates the satisfaction of students with a web-based information system at a medium-sized regional university. The analysis provides a process for simplifying data interpretation in captured student user feedback. Findings indicate that student classifications, as measured by demographic and other factors, determine satisfaction levels towards various web sources of information. Differences in satisfaction levels across student groups based on gender, age, minority status, employment, and current course load were found. Implications for university web designers and university administrators are considered and discussed
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