A Field Survey of Respiration Rates in Leaves of Arctic Plants

In a survey of several plant species found at Churchill, Manitoba, in the transition zone between the low and subarctic regions, we measured leaf respiration in terms of total respiration and alternative pathway respiration rates. Leaves of arctic plants exhibit higher rates of total respiration and alternative (cyanide insensitive) respiration than temperate species. There is a negative correlation between plant height and alternative pathway activity. Shorter plants have higher rates of alternative pathway respiration. More alternative pathway activity may mean that there is less energy in the form of ATP available for growth. A shorter growth habit keeps these plants in the still air close to the ground. This prevents cooling, water loss and physical damage due to wind abrasion. Thus plants with high rates of alternative pathway respiration may be better adapted to the arctic environment. The alternative pathway respiration of Orchis rotundifolia was shown to be under the influence of the biological clock.Key words: Subarctic, plant respiration, alternative pathway, cyanide insensitivMots clés: subarctique, respiration des plantes, voie alterne, insensible au cyanur

The Impact of Cloud-To-Ground Lightning Type on the Differences in Return Stroke Peak Current Over Land and Ocean

Natural cloud-to-ground (CG) lightning behaves differently over land and ocean. These differences likely reflect local variations in the speed at which storms develop over ocean, and are possibly contributed to by differences in the local aerosol composition. Earlier studies have reported statistically larger peak currents for negative CG first strokes over ocean than over land. This work focuses on differences in this relationship for first strokes, for subsequent strokes in existing channels to ground, and for subsequent strokes creating new ground contacts. This distinction will shed light on the mechanism responsible for the observed land:ocean differences, and can either support or refute the hypothesis that this difference is associated with the propagation of downward negative leaders in free space, driven by the vertical profile of electric field within and below the cloud. Results show that when compensated for detection threshold increases with increasing distance from land-based sensors, the distribution of estimated peak currents for subsequent strokes in existing (pre-ionized) channels to ground was indistinguishable from distributions for lightning that occurred inland, near shore, offshore, and in the distant ocean (similar to 200 km offshore), with median values ranging between 14.4 and 15.1 kA. Conversely, the population of first strokes over distant ocean had much higher peak currents than those that occurred inland (median values of 23.1 kA vs. 17.3 kA, respectively), when corrected for detection threshold. These findings are consistent with the field-profile hypothesis noted above since peak currents for return strokes due to downward leaders that establish new channels (first strokes) would be impacted the most by the vertical profile of electric field near the cloud base, whereas the peak current for strokes in previously-established channels should be far less dependent on the field profile.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Belimumab : a technological advance for systemic lupus erythematosus patients? Report of a systematic review and meta-analysis

Objectives: To undertake a systematic review and meta-analysis to investigate clinical effectiveness of belimumab for patients with systemic lupus erythematosus (SLE) and antinuclear and/or anti-double-stranded DNA (dsDNA) autoantibodies. Methods: We searched eight electronic databases and reference lists for randomised controlled trials (RCTs) of belimumab against placebo or best supportive care. Quality assessment and random effects meta-analysis were undertaken. Design: A meta-analysis of RCTs. Participants: 2133 SLE patients. Primary and secondary outcome measures: SLE Responder Index (SRI) at week 52. Results: Three double-blind placebo-controlled RCTs (L02, BLISS-52 BLISS-76) investigated 2133 SLE patients. BLISS-52 and BLISS-76 trials recruited patients with antinuclear and/or anti-dsDNA autoantibodies and demonstrated belimumab effectiveness for the SRI at week 52. Ethnicity and geographical location of participants varied considerably between BLISS trials. Although tests for statistical heterogeneity were negative, BLISS-52 results were systematically more favourable for all measured outcomes. Meta-analysis of pooled 52-week SRI BLISS results showed benefit for belimumab (OR 1.63, 95% CI 1.27 to 2.09). By week 76, the primary SRI outcome in BLISS-76 was not statistically significant (OR 1.31, 95% CI 0.919 to 1.855)

Reconstruction of coseismic slip from the 2015 Illapel earthquake using combined geodetic and tsunami waveform data

On 16 September 2015, a moment magnitude (Mw) 8.3 earthquake struck off the coast of central Chile, generating a large tsunami with nearby coastal wave heights observed on tide gauges in Chile and Peru of up to 4.7 m and distal observations of over 40 cm in the Kuril Islands across the Pacific Ocean. Through a transcoastal geodetic study, including tsunami time series recorded at open ocean pressure gauges, subaerial deformation observed through interferometric synthetic aperture radar from the Sentinel-1 A satellite and continuous GPS, we identify the location and extent of coseismic slip. We find that most coseismic slip was concentrated in a patch immediately offshore, with little modeled slip near the trench. This result satisfies the tsunami waveforms measured in the deep ocean north of the rupture area, with wave heights up to 10 cm. While the event exhibits some features of a slow tsunami earthquake (moderately large tsunami and possible slow second-stage rupture), our inversion results do not require substantial near-trench rupture. However, the prevalence of large and shallow thrust along subduction megathrusts along central Chile raises the question of the likelihood of future such events and the implications for future hazardous tsunamigenic earthquakesThis research was supported through State Funds through Georgia Tech to A.V.N. as well as through the National Science Foundation East Asian and Pacific Summer Institute project 1614142. P. Cummins was partially supported by Australian Research DP12010329

Managing cross boundary collaboration for value creation: lessons from a 'Blue Growth' initiative

New growth initiatives require collaboration across traditional sectors to develop eco-systems that can deliver sustainable sources of value. Collaborating across academic disciplines, the authors analyse a recent case of unprecedented collaboration between academia, government and industry in Ireland concerning marine innovation. Our analysis investigates: the effects of organizational structure and the characteristics of innovators; interpersonal dynamics that frustrate or enable cross-boundary teaming; and the role of senior executives in detecting, and responding to small deviations in expectations to avoid large-scale organizational failures. To leverage the potential benefits of cross-sector collaboration, we argue that leaders must engage in strategic error management. This paper extracts the value from the Irish case to find ways to avoid the mistakes of the relatively short-lived collaboration in future innovation efforts

The Function Acquisition Speed Test (FAST) as a Measure of Verbal Stimulus Relations in the Context of Condom Use

The Function Acquisition Speed Test (FAST) has shown recent evidence as an effective tool for the quantification of stimulus relatedness. The current study assessed the potential of the FAST in measuring the effects of the presentation of positively or negatively valenced messages on relatedness between stimulus relations with regard to safe-sex behavior, namely condom use. Fifty-one participants were assigned to one of three conditions comprised of valenced message interventions regarding the impact of condom use on the enjoyment of sexual behavior (each condition n = 17): a positive-message condition, a negative-message condition, or a no-message control condition. A significant Strength of Relation (SoR) score was found across positive and negative FAST test trials in the positive-message condition only, with no significant differences in SoR scores observed for either the Negative-message or Control conditions. These data suggest that the FAST may have utility as a sensitive behavioral tool for measuring changes in stimulus relations concerning safe-sex behavior on the basis of brief message interventions

Media representations of opposition to the 'junk food advertising ban' on the Transport for London (TfL) network: A thematic content analysis of UK news and trade press.

BackgroundAdvertising of less healthy foods and drinks is hypothesised to be associated with obesity in adults and children. In February 2019, Transport for London implemented restrictions on advertisements for foods and beverages high in fat, salt or sugar across its network as part of a city-wide strategy to tackle childhood obesity. The policy was extensively debated in the press. This paper identifies arguments for and against the restrictions. Focusing on arguments against the restrictions, it then goes on to deconstruct the discursive strategies underpinning them.MethodsA qualitative thematic content analysis of media coverage of the restrictions (the 'ban') in UK newspapers and trade press was followed by a document analysis of arguments against the ban. A search period of March 1, 2018 to May 31, 2019 covered: (i) the launch of the public consultation on the ban in May 2018; (ii) the announcement of the ban in November 2018; and (iii) its implementation in February 2019. A systematic search of printed and online publications in English distributed in the UK or published on UK-specific websites identified 152 articles.ResultsArguments in favour of the ban focused on inequalities and childhood obesity. Arguments against the ban centred on two claims: that childhood obesity was not the 'right' priority; and that an advertising ban was not an effective way to address childhood obesity. These claims were justified via three discursive approaches: (i) claiming more 'important' priorities for action; (ii) disputing the science behind the ban; (iii) emphasising potential financial costs of the ban.ConclusionThe discursive tactics used in media sources to argue against the ban draw on frames widely used by unhealthy commodities industries in response to structural public health interventions. Our analyses highlight the need for interventions to be framed in ways that can pre-emptively counter common criticisms