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Ground-level ozone influenced by circadian control of isoprene emissions

The volatile organic compound isoprene is produced by many plant species, and provides protection against biotic and abiotic stresses1. Globally, isoprene emissions from plants are estimated to far exceed anthropogenic emissions of volatile organic compounds2. Once in the atmosphere, isoprene reacts rapidly with hydroxyl radicals3 to form peroxy radicals, which can react with nitrogen oxides to fo

The influence of small-scale variations in isoprene concentrations on atmospheric chemistry over a tropical rainforest

Biogenic volatile organic compounds (BVOCs) such as isoprene constitute a large proportion of the global atmospheric oxidant sink. Their reactions in the atmosphere contribute to processes such as ozone production and secondary organic aerosol formation. However, over the tropical rainforest, where 50 % of the global emissions of BVOCs are believed to occur, atmospheric chemistry models have been

Modelling chemistry in the nocturnal boundary layer above tropical rainforest and a generalised effective nocturnal ozone deposition velocity for sub-ppbv NOx conditions

Measurements of atmospheric composition have been made over a remote rainforest landscape. A box model has previously been demonstrated to model the observed daytime chemistry well. However the box model is unable to explain the nocturnal measurements of relatively high [NO] and [O3], but relatively low observed [NO2]. It is shown that a one-dimensional (1-D) column model with simple O3-NOx chemis

Fluxes and concentrations of volatile organic compounds from a South-East Asian tropical rainforest

As part of the OP3 field study of rainforest atmospheric chemistry, above-canopy fluxes of isoprene, monoterpenes and oxygenated volatile organic compounds were made by virtual disjunct eddy covariance from a South-East Asian tropical rainforest in Malaysia. Approximately 500 hours of flux data were collected over 48 days in April-May and June-July 2008. Isoprene was the dominant non-methane hydro

Nitrogen management is essential to prevent tropical oil palm plantations from causing ground-level ozone pollution

More than half the world's rainforest has been lost to agriculture since the Industrial Revolution. Among the most widespread tropical crops is oil palm (Elaeis guineensis): global production now exceeds 35 million tonnes per year. In Malaysia, for example, 13% of land area is now oil palm plantation, compared with 1% in 1974. There are enormous pressures to increase palm oil production for food,

Analysis of manufacturing costs for powder metallurgy (pm) gear manufacturing processes : a case study of a helical drive gear

This paper presents a thorough manufacturing cost analysis for a powder metallurgy (PM) manufactured gear (using press and sintering technique—P/S), through a case study of a R&D 4th drive gear (a helical gearwheel) utilizing both real usage data from six companies and some estimated data from literatures. The chosen costs calculation method, performance part costing (PPC), is comprehensive an

Drawing the Line Between Essential and Nonessential Interventions on Intersex Characteristics With European Health Care Professionals

Human rights statements on intersex characteristics distinguish legitimate “medically necessary” interventions from illegitimate normalizing ones. Ironically, this binary classification seems partially grounded in knowledge of anatomy and medical interventions; the very expertise that human rights statements challenge. Here, 23 European health professionals from specialist “disorder of sex developHuman rights statements on intersex characteristics distinguish legitimate “medically necessary” interventions from illegitimate normalizing ones. Ironically, this binary classification seems partially grounded in knowledge of anatomy and medical interventions; the very expertise that human rights statements challenge. Here, 23 European health professionals from specialist “disorder of sex develop

Simulation of collective phenomena in microswimmer suspensions

Collective motion is ubiquitous in biological and synthetic systems across manylength- and timescales. On the macroscopic scale, examples include schools of fish, herds of sheep and flocks of birds. On the microscopic scale, bacteria, algae and synthetic self-propelled particles exhibit a range of collective phenomena. In suspensions of swimming bacteria, collective motion is often caused by hydro

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Recension av Gunilla Svensmark. Kald og profession – Sygeplejens historie 1863-2001. FADL’s Forlag, 2020

Quantifying archaeo-organic degradation – A multiproxy approach to understand the accelerated deterioration of the ancient organic cultural heritage at the Swedish Mesolithic site Ageröd

Despite a growing body of evidence concerning accelerated organic degradation at archaeological sites, there have been few follow-up investigations to examine the status of the remaining archaeological materials in the ground. To address the question of archaeo-organic preservation, we revisited the Swedish, Mesolithic key-site Ageröd and could show that the bone material had been subjected to an

Unannounced Evacuation Experiment in a High-Rise Hotel Building with Evacuation Elevators : A Study of Evacuation Behaviour Using Eye-Tracking

Past studies suggest that people are often reluctant to use occupant evacuation elevators in case of fire. However, existing research is scarce and current knowledge is based on questionnaire studies and laboratory experiments. An unannounced evacuation experiment was therefore performed on the 16th floor of a 35-floor high-rise hotel building. Sixty-seven participants took part and eye-tracking g