SUPERCONDUCTING CURRENT LEADS OF YBCO AND PB-BSCCO

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Suspended particles are hotspots of microbial remineralization in the ocean's twilight zone

The sinking of photosynthetically produced organic carbon from the ocean surface to its interior is a significant term in the global carbon cycle. Most sinking organic carbon is, however, remineralized in the mesopelagic zone (∼100 m–1000 m), thereby exerting control over ocean-atmosphere carbon dioxide (CO2) partitioning and hence global climate. Sinking particles are considered hotspots of microbial respiration in the dark ocean. However, our observations in the contrasting Scotia Sea and the Benguela Current show that >90% of microbial remineralisation is associated with suspended, rather than sinking, organic matter, resulting in rapid turnover of the suspended carbon pool and demonstrating its central role in mesopelagic carbon cycling. A non-steady-state model indicates that temporally variable particle fluxes, particle injection pumps and local chemoautotrophy are necessary to help balance the observed mesopelagic respiration. Temperature and oxygen exert control over microbial respiration, particularly for the suspended fraction, further demonstrating the susceptibility of microbial remineralisation to the ongoing decline in oxygen at mid-ocean depths. These observations suggest a partial decoupling of carbon cycling between non-sinking and fast-sinking organic matter, challenging our understanding of how oceanic biological processes regulate climate

Collective Action and Decision Making: An Analysis of Economic Modeling and Environmental Free-Riding

It is hypothesized that tool-assisted excavation of plant underground storage organs (USOs) played an adaptive role in hominin evolution and was also once considered a uniquely human behavior. Recent data indicate that savanna chimpanzees also use tools to excavate edible USOs. However, those chimpanzees remain largely unhabituated and we lack direct observations of this behavior in the wild. To fill this gap in our knowledge of hominoid USO extractive foraging, we conducted tool-mediated excavation experiments with captive chimpanzees naive to this behavior. We presented the chimpanzees with the opportunity to use tools in order to excavate artificially-placed underground foods in their naturally forested outdoor enclosure. No guidance or demonstration was given to the chimpanzees at any time. The chimpanzees used tools spontaneously in order to excavate the underground foods. They exhibited six different tool use behaviors in the context of excavation: probe, perforate, dig, pound, enlarge and shovel. However, they still excavated manually more often than they did with tools. Chimpanzees were selective in their choice of tools that we provided, preferring longer tools for excavation. They also obtained their own tools mainly from naturally occurring vegetation and transported them to the excavation site. They reused some tools throughout the study. Our new data provide a direction for the study of variables relevant to modeling USO extractive foraging by early hominins.Funding Agencies|La Caixa Foundation Spain [LCF/BQ/EU15/10350002]; University of Oslo, Department of Biosciences, Norway</p

Multi-layered control of Galectin-8 mediated autophagy during adenovirus cell entry through a conserved PPxY motif in the viral capsid.

Cells employ active measures to restrict infection by pathogens, even prior to responses from the innate and humoral immune defenses. In this context selective autophagy is activated upon pathogen induced membrane rupture to sequester and deliver membrane fragments and their pathogen contents for lysosomal degradation. Adenoviruses, which breach the endosome upon entry, escape this fate by penetrating into the cytosol prior to autophagosome sequestration of the ruptured endosome. We show that virus induced membrane damage is recognized through Galectin-8 and sequesters the autophagy receptors NDP52 and p62. We further show that a conserved PPxY motif in the viral membrane lytic protein VI is critical for efficient viral evasion of autophagic sequestration after endosomal lysis. Comparing the wildtype with a PPxY-mutant virus we show that depletion of Galectin-8 or suppression of autophagy in ATG5-/- MEFs rescues infectivity of the PPxY-mutant virus while depletion of the autophagy receptors NDP52, p62 has only minor effects. Furthermore we show that wildtype viruses exploit the autophagic machinery for efficient nuclear genome delivery and control autophagosome formation via the cellular ubiquitin ligase Nedd4.2 resulting in reduced antigenic presentation. Our data thus demonstrate that a short PPxY-peptide motif in the adenoviral capsid permits multi-layered viral control of autophagic processes during entry

Ab initio study of the modification of elastic properties of alpha-iron by hydrostatic strain and by hydrogen interstitials

The effect of hydrostatic strain and of interstitial hydrogen on the elastic properties of $\alpha$-iron is investigated using \textit{ab initio} density-functional theory calculations. We find that the cubic elastic constants and the polycrystalline elastic moduli to a good approximation decrease linearly with increasing hydrogen concentration. This net strength reduction can be partitioned into a strengthening electronic effect which is overcome by a softening volumetric effect. The calculated hydrogen-dependent elastic constants are used to determine the polycrystalline elastic moduli and anisotropic elastic shear moduli. For the key slip planes in $\alpha$-iron, $[1\bar{1}0]$ and $[11\bar{2}]$, we find a shear modulus reduction of approximately 1.6% per at.% H.Comment: Updated first part of 1009.378

Temporal shifts in prokaryotic metabolism in response to organic carbon dynamics in the mesopelagic ocean during an export event in the Southern ocean

As the major term in downward organic carbon flux attenuation, determining prokaryotic metabolism over depth in the mesopelagic ocean is crucial for constraining the efficiency of the gravitational biological carbon pump (BCP). We hypothesize that the enhancement of particulate organic carbon (POC) concentrations in the mesopelagic twilight zone during export events leads to a temporally dynamic prokaryotic metabolic response, which likely has consequences for the efficiency of the BCP. We tested this hypothesis by making repeated measurements of leucine assimilation and leucine respiration at in situ concentrations over six depths throughout the upper 500 m of the water column during the collapse of a large-scale Southern Ocean spring diatom bloom. Rates of prokaryotic leucine assimilation were used to indicate levels of prokaryotic heterotrophic production, and leucine assimilation efficiency (LAE; the proportion of leucine used for growth versus respiration) was taken as an indicator of prokaryotic growth efficiency. Thus, relative shifts in LAE are indicative of shifts in rates of prokaryotic production relative to respiration. The flux of POC through the oceans’ interior led to a dynamic prokaryotic response, characterized by a temporary elevation in mesopelagic prokaryote leucine assimilation rates, LAE and prokaryotic abundance. By the final measurement these changes had already begun to revert, despite POC concentrations still being enriched. As hypothesized, our data revealed distinctions in the phases of the mesopelagic system, likely due to an evolution in bulk prokaryotic metabolic status and the amount and composition of organic matter available. This indicates that estimating ocean carbon sequestration during export events necessitates a time course of measurements throughout the period of POC downward flux. Our findings also revealed distinctions in the ecophysiological prokaryotic responses to substrate regimes between the surface mixed layer and the mesopelagic. Specifically, in the latter in situ leucine concentrations appeared more significant in controlling prokaryote metabolism than POC concentration, and were more closely related to per cell leucine assimilation, than respiration. Whereas, in the mixed layer, the concentration of in situ leucine did not seem to drive rates of its assimilation, rather POC concentration was a strong negative driver of cell specific leucine respiration. These findings are suggestive of stronger levels of energy limitation in the deeper ocean. We surmised that ocean regions with sporadic substrate supply to the mesopelagic are likely to experience stronger energy limitation which favors prokaryotic respiration over production

The power of practice: simulation training improving the quality of neonatal resuscitation skills in Bihar, India.

BACKGROUND: Globally, neonatal mortality accounts for nearly half of under-five mortality, and intrapartum related events are a leading cause. Despite the rise in neonatal resuscitation (NR) training programs in low- and middle-income countries, their impact on the quality of NR skills amongst providers with limited formal medical education, particularly those working in rural primary health centers (PHCs), remains incompletely understood. METHODS: This study evaluates the impact of PRONTO International simulation training on the quality of NR skills in simulated resuscitations and live deliveries in rural PHCs throughout Bihar, India. Further, it explores barriers to performance of key NR skills. PRONTO training was conducted within CARE India's AMANAT intervention, a maternal and child health quality improvement project. Performance in simulations was evaluated using video-recorded assessment simulations at weeks 4 and 8 of training. Performance in live deliveries was evaluated in real time using a mobile-phone application. Barriers were explored through semi-structured interviews with simulation facilitators. RESULTS: In total, 1342 nurses participated in PRONTO training and 226 NR assessment simulations were matched by PHC and evaluated. From week 4 to 8 of training, proper neck extension, positive pressure ventilation (PPV) with chest rise, and assessment of heart rate increased by 14%, 19%, and 12% respectively (all p ≤ 0.01). No difference was noted in stimulation, suction, proper PPV rate, or time to completion of key steps. In 252 live deliveries, identification of non-vigorous neonates, use of suction, and use of PPV increased by 21%, 25%, and 23% respectively (all p < 0.01) between weeks 1-3 and 4-8. Eighteen interviews revealed individual, logistical, and cultural barriers to key NR skills. CONCLUSION: PRONTO simulation training had a positive impact on the quality of key skills in simulated and live resuscitations throughout Bihar. Nevertheless, there is need for ongoing improvement that will likely require both further clinical training and addressing barriers that go beyond the scope of such training. In settings where clinical outcome data is unreliable, data triangulation, the process of synthesizing multiple data sources to generate a better-informed evaluation, offers a powerful tool for guiding this process

Model-free tuning of laguerre network for impedance matching in bilateral teleoperation system

This paper addresses the tuning method to attain symmetry between the master and slave manipulators of a bilateral teleoperation system. In the proposed structure, an equalizer based on the Laguerre network connected in-feedback loop to the master manipulator has been introduced. A set of input-output data were first generated and recorded which later be used in two-steps tuning procedure. A fictitious reference signal was formulated based on these data. In addition, a metaheuristic optimization algorithm namely the Particle Swarm Optimization has been employed in seeking the optimal controller’s parameters. Numerical analyses utilizing Matlab software has been performed. The results exhibited that the dynamic of the master manipulator with the added controller is almost identical to the dynamic of the slave systems. Hence, it is verified that the proposed tuning technique is feasible to achieve symmetry between both sides of the manipulators