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Collaboration is an important 21st Century skill. Co-located (or face-to-face) collaboration (CC) analytics gained momentum with the advent of sensor technology. Most of these works have used the audio modality to detect the quality of CC. The CC quality can be detected from simple indicators of collaboration such as total speaking time or complex indicators like synchrony in the rise and fall of the average pitch. Most studies in the past focused on 'how group members talk' (i.e., spectral, temporal features of audio like pitch) and not 'what they talk'. The 'what' of the conversations is more overt contrary to the 'how' of the conversations. Very few studies studied 'what' group members talk about, and these studies were lab based showing a representative overview of specific words as topic clusters instead of analysing the richness of the content of the conversations by understanding the linkage between these words. To overcome this, we made a starting step in this technical paper based on field trials to prototype a tool to move towards automatic collaboration analytics. We designed a technical setup to collect, process and visualize audio data automatically. The data collection took place while a board game was played among the university staff with pre-assigned roles to create awareness of the connection between learning analytics and learning design. We not only did a word-level analysis of the conversations, but also analysed the richness of these conversations by visualizing the strength of the linkage between these words and phrases interactively. In this visualization, we used a network graph to visualize turn taking exchange between different roles along with the word-level and phrase-level analysis. We also used centrality measures to understand the network graph further based on how much words have hold over the network of words and how influential are certain words. Finally, we found that this approach had certain limitations in terms of automation in speaker diarization (i.e., who spoke when) and text data pre-processing. Therefore, we concluded that even though the technical setup was partially automated, it is a way forward to understand the richness of the conversations between different roles and makes a significant step towards automatic collaboration analytics. (DIPF/Orig.).

Objective The purpose of the present study was to investigate the association between cardiorespiratory fitness (CRF) measured as peak oxygen uptake (VO 2peak , expressed in mL/min) and body mass index (BMI) in a large cohort of apparently healthy subjects. Methods BMI and VO 2peak were measured in a cross-sectional study of 8470 apparently healthy adults. VO 2peak (mL/min) was determined by an incremental cycle ergometer test to exhaustion. Linear regression analyses were performed to identify predictors of CRF. Results There was no difference in CRF between adults with a normal weight ( BMI between 18.5–24.9 kg/m 2 ) and those who were overweight ( BMI 25.0–29.9 kg/m 2 ). Subjects who were underweight ( BMI < 18.5 kg/m 2 ) as well as females who were obese (BMI ≥ 30.0 kg/m 2 ) showed a reduced CRF compared to the normal and overweight groups. Age, height, and gender were significant predictors of CRF ( R 2  = 0.467, P  < 0.0001); BMI did not add significantly to this relationship. Conclusion Our findings indicate that BMI was not associated with CRF in addition to age, height, and gender. In subjects with a BMI < 18.5 kg/m 2 , CRF was lower compared to subjects with a BMI between 18.5 and 29.9 kg/m 2 . In obese subjects, CRF was only lower in females compared to females with a BMI between 18.5 and 29.9 kg/m 2 . Correcting CRF for BMI may be beneficial for subjects with a low BMI, and females with a BMI ≥ 30.0 kg/m 2 . The outcome of this study might help to improve the interpretation of exercise testing results in individuals with a low or high BMI.

In Eastern Boundary Upwelling Systems nutrient-rich waters are transported to the ocean surface, fuelling high photoautotrophic primary production. Subsequent heterotrophic decomposition of the produced biomass increases the oxygen-depletion at intermediate water depths, which can result in the formation of oxygen minimum zones (OMZ). OMZs can sporadically accumulate hydrogen sulfide (H2S), which is toxic to most multicellular organisms and has been implicated in massive fish kills. During a cruise to the OMZ off Peru in January 2009 we found a sulfidic plume in continental shelf waters, covering an area >5500 km(2), which contained ∼2.2×10(4) tons of H2S. This was the first time that H2S was measured in the Peruvian OMZ and with ∼440 km(3) the largest plume ever reported for oceanic waters. We assessed the phylogenetic and functional diversity of the inhabiting microbial community by high-throughput sequencing of DNA and RNA, while its metabolic activity was determined with rate measurements of carbon fixation and nitrogen transformation processes. The waters were dominated by several distinct γ-, δ- and ε-proteobacterial taxa associated with either sulfur oxidation or sulfate reduction. Our results suggest that these chemolithoautotrophic bacteria utilized several oxidants (oxygen, nitrate, nitrite, nitric oxide and nitrous oxide) to detoxify the sulfidic waters well below the oxic surface. The chemolithoautotrophic activity at our sampling site led to high rates of dark carbon fixation. Assuming that these chemolithoautotrophic rates were maintained throughout the sulfidic waters, they could be representing as much as ∼30% of the photoautotrophic carbon fixation. Postulated changes such as eutrophication and global warming, which lead to an expansion and intensification of OMZs, might also increase the frequency of sulfidic waters. We suggest that the chemolithoautotrophically fixed carbon may be involved in a negative feedback loop that could fuel further sulfate reduction and potentially stabilize the sulfidic OMZ waters.

Oxygen minimum zones are major sites of fixed nitrogen loss in the ocean. Recent studies have highlighted the importance of anaerobic ammonium oxidation, anammox, in pelagic nitrogen removal. Sources of ammonium for the anammox reaction, however, remain controversial, as heterotrophic denitrification and alternative anaerobic pathways of organic matter remineralization cannot account for the ammonium requirements of reported anammox rates. Here, we explore the significance of microaerobic respiration as a source of ammonium during organic matter degradation in the oxygen-deficient waters off Namibia and Peru. Experiments with additions of double-labelled oxygen revealed high aerobic activity in the upper OMZs, likely controlled by surface organic matter export. Consistently observed oxygen consumption in samples retrieved throughout the lower OMZs hints at efficient exploitation of vertically and laterally advected, oxygenated waters in this zone by aerobic microorganisms. In accordance, metagenomic and metatranscriptomic analyses identified genes encoding for aerobic terminal oxidases and demonstrated their expression by diverse microbial communities, even in virtually anoxic waters. Our results suggest that microaerobic respiration is a major mode of organic matter remineralization and source of ammonium (~45-100%) in the upper oxygen minimum zones, and reconcile hitherto observed mismatches between ammonium producing and consuming processes therein.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the rapidly unfolding coronavirus disease 2019 (COVID-19) pandemic 1 , 2 . Clinical manifestations of COVID-19 vary, ranging from asymptomatic infection to respiratory failure. The mechanisms that determine such variable outcomes remain unresolved. Here we investigated CD4 + T cells that are reactive against the spike glycoprotein of SARS-CoV-2 in the peripheral blood of patients with COVID-19 and SARS-CoV-2-unexposed healthy donors. We detected spike-reactive CD4 + T cells not only in 83% of patients with COVID-19 but also in 35% of healthy donors. Spike-reactive CD4 + T cells in healthy donors were primarily active against C-terminal epitopes in the spike protein, which show a higher homology to spike glycoproteins of human endemic coronaviruses, compared with N-terminal epitopes. Spike-protein-reactive T cell lines generated from SARS-CoV-2-naive healthy donors responded similarly to the C-terminal region of the spike proteins of the human endemic coronaviruses 229E and OC43, as well as that of SARS-CoV-2. This results indicate that spike-protein cross-reactive T cells are present, which were probably generated during previous encounters with endemic coronaviruses. The effect of pre-existing SARS-CoV-2 cross-reactive T cells on clinical outcomes remains to be determined in larger cohorts. However, the presence of spike-protein cross-reactive T cells in a considerable fraction of the general population may affect the dynamics of the current pandemic, and has important implications for the design and analysis of upcoming trials investigating COVID-19 vaccines. A study of patients with COVID-19 and healthy donors found CD4 + T cells that react to the spike protein of SARS-CoV-2 and human endemic coronaviruses; however, the effect of pre-existing SARS-CoV-2 cross-reactive T cells on clinical outcomes remains to be determined.

This paper presents the design and implementation of a SLAM-based online mapping and autonomous trajectory execution system for the Nimbulus-e, a concept vehicle designed for agile maneuvering in confined spaces. The Nimbulus-e uses individual steer-by-wire corner modules with in-wheel motors at all four corners. The associated eight joint variables serve as control inputs, allowing precise trajectory following. These control inputs can be derived from the vehicle’s trajectory using nonholonomic constraints. A LiDAR sensor is used to map the environment and detect obstacles. The system processes LiDAR data in real time, continuously updating the environment map and enabling localization within the environment. The inclusion of vehicle odometry data significantly reduces computation time and improves accuracy compared to a purely visual approach. The A* and Hybrid A* algorithms are used for trajectory planning and optimization, ensuring smooth vehicle movement. The implementation is validated through both full vehicle simulations using an ADAMS Car—MATLAB co-simulation and a scaled physical prototype, demonstrating the effectiveness of the system in navigating complex environments. This work contributes to the field of autonomous systems by demonstrating the potential of combining advanced sensor technologies with innovative control algorithms to achieve reliable and efficient navigation. Future developments will focus on improving the robustness of the system by implementing a robust closed-loop controller and exploring additional applications in dense urban traffic and agricultural operations.

Members of the gammaproteobacterial clade SUP05 couple water column sulfide oxidation to nitrate reduction in sulfidic oxygen minimum zones (OMZs). Their abundance in offshore OMZ waters devoid of detectable sulfide has led to the suggestion that local sulfate reduction fuels SUP05-mediated sulfide oxidation in a so-called “cryptic sulfur cycle”. We examined the distribution and metabolic capacity of SUP05 in Peru Upwelling waters, using a combination of oceanographic, molecular, biogeochemical and single-cell techniques. A single SUP05 species, U Thioglobus perditus , was found to be abundant and active in both sulfidic shelf and sulfide-free offshore OMZ waters. Our combined data indicated that mesoscale eddy-driven transport led to the dispersal of U T. perditus and elemental sulfur from the sulfidic shelf waters into the offshore OMZ region. This offshore transport of shelf waters provides an alternative explanation for the abundance and activity of sulfide-oxidizing denitrifying bacteria in sulfide-poor offshore OMZ waters. The presence and activity of sulfide-oxidizing denitrifying bacteria in sulfide-poor offshore oxygen minimum zone waters remains unclear. Here, the authors combine oceanography, molecular, biogeochemical and single-cell techniques to examine their distribution, metabolic capacity, and origins.

A newly developed method of measuring oceanic nitrogen-fixation rates provides significantly higher estimates than a current widely applied technique, and could close gaps in the marine nitrogen budget. A question of nitrogen balance Attempts to produce a balanced marine nitrogen budget on the basis of direct measurements have proved difficult, with nitrogen loss exceeding the gain by dinitrogen (N 2 ) fixation. Here, Julie LaRoche and colleagues report a possible reason for this problem. They suggest that a method widely used to measure oceanic N 2 -fixation rates significantly and variably underestimates the contribution of microorganisms known as diazotrophs. This emerges from comparisons with fixed nitrogen measurements made with a newly developed method in the Atlantic Ocean. If the findings could be extrapolated to other ocean basins, N 2 -fixation rates would be almost double current estimates, a significant narrowing of the gap between nitrogen loss and gain. Biological dinitrogen fixation provides the largest input of nitrogen to the oceans, therefore exerting important control on the ocean's nitrogen inventory and primary productivity 1 , 2 , 3 . Nitrogen-isotope data from ocean sediments suggest that the marine-nitrogen inventory has been balanced for the past 3,000 years (ref. 4 ). Producing a balanced marine-nitrogen budget based on direct measurements has proved difficult, however, with nitrogen loss exceeding the gain from dinitrogen fixation by approximately 200 Tg N yr −1 (refs 5 , 6 ). Here we present data from the Atlantic Ocean and show that the most widely used method of measuring oceanic N 2 -fixation rates 7 underestimates the contribution of N 2 -fixing microorganisms (diazotrophs) relative to a newly developed method 8 . Using molecular techniques to quantify the abundance of specific clades of diazotrophs in parallel with rates of 15 N 2 incorporation into particulate organic matter, we suggest that the difference between N 2 -fixation rates measured with the established method 7 and those measured with the new method 8 can be related to the composition of the diazotrophic community. Our data show that in areas dominated by Trichodesmium , the established method underestimates N 2 -fixation rates by an average of 62%. We also find that the newly developed method yields N 2 -fixation rates more than six times higher than those from the established method when unicellular, symbiotic cyanobacteria and γ-proteobacteria dominate the diazotrophic community. On the basis of average areal rates measured over the Atlantic Ocean, we calculated basin-wide N 2 -fixation rates of 14 ± 1 Tg N yr −1 and 24 ±1 Tg N yr −1 for the established and new methods, respectively. If our findings can be extrapolated to other ocean basins, this suggests that the global marine N 2 -fixation rate derived from direct measurements may increase from 103 ± 8 Tg N yr −1 to 177 ± 8 Tg N yr −1 , and that the contribution of N 2 fixers other than Trichodesmium is much more significant than was previously thought.

Channelrhodopsins are light-gated ion channels used to control excitability of designated cells in large networks with high spatiotemporal resolution. While ChRs selective for H + , Na + , K + and anions have been discovered or engineered, Ca 2+ -selective ChRs have not been reported to date. Here, we analyse ChRs and mutant derivatives with regard to their Ca 2+ permeability and improve their Ca 2+ affinity by targeted mutagenesis at the central selectivity filter. The engineered channels, termed CapChR1 and CapChR2 for ca lcium- p ermeable ch annel r hodopsins, exhibit reduced sodium and proton conductance in connection with strongly improved Ca 2+ permeation at negative voltage and low extracellular Ca 2+ concentrations. In cultured cells and neurons, CapChR2 reliably increases intracellular Ca 2+ concentrations. Moreover, CapChR2 can robustly trigger Ca 2+ signalling in hippocampal neurons. When expressed together with genetically encoded Ca 2+ indicators in Drosophila melanogaster mushroom body output neurons, CapChRs mediate light-evoked Ca 2+ entry in brain explants. To date, no Ca2 + -selective channelrhodopsins have been characterized. In this study, Fernandez Lahore et al. report two calcium-permeable channelrhodopsins (CapChR1 and 2) for the photocontrol of calcium signalling in excitable tissue.