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Manganese (Mn) is key to oxygenic photosynthesis as it catalyzes the splitting of water in photosystem II and functions as cofactor of multiple enzymes. A single ABC-type transporter, MntCAB, is so far established for the uptake of the metal under limiting conditions in cyanobacteria. It is unknown, how Mn is imported under replete conditions. We identified two proteins in the model cyanobacterium Synechocystis sp. PCC 6803, which are homologous to the unknown protein family 0016 (UPF0016) member manganese exporter (Mnx). In contrast to Mnx, which consists of six transmembrane domains, the new candidate proteins contain only three transmembrane domains. Hence, we named them hemi manganese exporter (Hmx) 1 and 2. Knock-out mutants in hmx1 and/or hmx2 showed sensitivity toward low Mn supplementation, and reduced intracellular Mn pools. Additional deletion of mntC hindered the cells to thrive unless external Mn was added and enhanced the depletion of their intracellular Mn pool. In accordance with the observed localization of Hmx1 and Hmx2 in the plasma membrane, we postulate a Mn uptake function for a heteromeric Hmx1/2 across the plasma membrane under a wide range of Mn concentrations and a supporting role for the MntCAB system under Mn-limiting conditions. On the basis of their phylogenies, we propose that Hmx1 and Hmx2 are the ancestral progenitors of eukaryote-type UPF0016 proteins with six transmembrane domains. The Mn transport function of Hmx1/2 underscores this as fundamental ancient feature of the UPF0016 family. Likely, Hmx1 and Hmx2 coevolved with the internalization of the oxygen-evolving complex.

INTRODUCTION: A typical training plan is a mix of many interventions, such as runs of different lengths and intensities. It is virtually impossible to measure the effectiveness of such a complex, months-long intervention in high quality intervention trials such as a randomised control trial [1]. To start addressing this evidence problem, Haugen et al. have summarised training plans of elite athletes that have achieved world-class performance despite or because of the training plan [2]. They termed this approach results-based practice. The aim of this study was to use a novel systematic review strategy to quantitatively analyse subjective sub-elite marathon training plans in order to determine a typical marathon training recommendation and report recommended training strategies. METHODS: We obtained training plans from non-scientific sources using the search term “marathon training”. We found 92 training plans and transcribed them into a uniform format with the goal to split each session into a kilometre distance in each of the five intensity zones [3]. To do this, two researchers independently agreed upon the classification for each session. Subsequently, each training plan was grouped based on the total mileage in the peak week, defined as highest volume week, into low (< 65 km/week), middle (65-90 km/week), and high (> 90 km/week) training volume. RESULTS: Low mileage training plans had an average weekly volume of 43.5 ± 15.5 km that was split into 9.9 ± 3.6% in zone 1, 68.6 ± 5.7% in zone 2, 16.5 ± 5.9% in zone 3, 2.8 ± 1.0% in zone 4, and 2.2 ± 0.5% in zone 5. Low mileage training plans recommend the shortest weekly long runs of 20.5 ± 8.3 km (p < .001). Next, the middle mileage training plans recommended an average weekly volume of 58.1 ± 19.4 km with 15.4 ± 1.8% in zone 1, 61.3 ± 4.5% in zone 2, 17.6 ± 5.1% in zone 3, 2.3 ± 0.6% in zone 4, and 3.3 ± 0.5% in zone 5, and recommended an average weekly long run session of 23.0 ± 8.3 km. Lastly, high mileage traini

This learning module is designed for the teacher of children in the middle school years. The purpose is to prepare the teacher to foster in the children a positive self-image thus improving their academic achievement and ability to cope with life situations. The module contains self-evaluation tests and perception tests as well as an extensive bibliography for further reading on the subject. (JD)