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The biological reduction of CO 2 into multicarbon chemicals can be driven by electrons derived from the cathode of a bioelectrochemical reactor via microbial electrosynthesis (MES). To increase MES productivity, conditions for optimal electron transfer between the cathode and the microbial catalyst must be implemented. Here, we report the development of a 3D-graphene functionalized carbon felt composite cathode enabling faster electron transfer to the microbial catalyst Sporomusa ovata in a MES reactor. Modification with 3D-graphene network increased the electrosynthesis rate of acetate from CO 2 by 6.8 fold. It also significantly improved biofilm density and current consumption. A 2-fold increase in specific surface area of the 3D-graphene/carbon felt composite cathode explained in part the formation of more substantial biofilms compared to untreated control. Furthermore, in cyclic voltammetry analysis, 3D-graphene/carbon felt composite cathode exhibited higher current response. The results indicate that the development of a 3D-network cathode is an effective approach to improve microbe-electrode interactions leading to productive MES systems.

When a person executes a movement, the movement is more errorful while observing another person's actions that are incongruent rather than congruent with the executed action. This effect is known as "motor contagion". Accounts of this effect are often grounded in simulation mechanisms: increased movement error emerges because the motor codes associated with observed actions compete with motor codes of the goal action. It is also possible, however, that the increased movement error is linked to eye movements that are executed simultaneously with the hand movement because oculomotor and manual-motor systems are highly interconnected. In the present study, participants performed a motor contagion task in which they executed horizontal arm movements while observing a model making either vertical (incongruent) or horizontal (congruent) movements under three conditions: no instruction, maintain central fixation, or track the model's hand with the eyes. A significant motor contagion-like effect was only found in the 'track' condition. Thus, 'motor contagion' in the present task may be an artifact of simultaneously executed incongruent eye movements. These data are discussed in the context of stimulation and associative learning theories, and raise eye movements as a critical methodological consideration for future work on motor contagion.

The utilization of visual information for the control of ongoing voluntary limb movements has been investigated for more than a century. Recently, online sensorimotor processes for the control of upper-limb reaches were hypothesized to include a distinct process related to the comparison of limb and target positions (i.e., limb-target regulation processes: Elliott et al. in Psychol Bull 136:1023–1044. doi: 10.1037/a0020958 , 2010). In the current study, this hypothesis was tested by presenting participants with brief windows of vision (20 ms) when the real-time velocity of the reaching limb rose above selected velocity criteria. One experiment tested the perceptual judgments of endpoint bias (i.e., under- vs. over-shoot), and another experiment tested the shifts in endpoint distributions following an imperceptible target jump. Both experiments revealed that limb-target regulation processes take place at an optimal velocity or “sweet spot” between movement onset and peak limb velocity (i.e., 1.0 m/s with the employed movement amplitude and duration). In contrast with pseudo-continuous models of online control (e.g., Elliott et al. in Hum Mov Sci 10:393–418. doi: 10.1016/0167-9457(91)90013-N , 1991), humans likely optimize online limb-target regulation processes by gathering visual information at a rather limited period of time, well in advance of peak limb velocity.

Microbial contribution to the maintenance and turnover of soil organic matter is significant. Yet, we do not have a thorough understanding of how biochemical composition of soil microbial biomass is related to carbon turnover and persistence of different microbial components. Using a suite of state-of-the-art analytical techniques, we investigated the molecular characteristics of extractable microbial biomass and linked it to its carbon turnover time. A 13CO2 plant pulse labelling experiment was used to trace plant carbon into rhizosphere soil microbial biomass, which was obtained by chloroform fumigation extraction (CFE). 13C content in molecular size classes of extracted microbial compounds was analysed using size exclusion chromatography (SEC) coupled online to high performance liquid chromatography–isotope ratio mass spectrometry (SEC-HPLC-IRMS). Molecular characterization of microbial compounds was performed using complementary approaches, namely SEC-HPLC coupled to Fourier transform infrared spectroscopy (SEC-HPLC-FTIR) and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR-MS). SEC-HPLC-FTIR suggests that mid to high molecular weight (MW) microbial compounds were richer in aliphatic CH bonds, carbohydrate-like compounds and possibly Pdouble bond; length as m-dashO derivatives from phospholipids. On the contrary, the lower size range was characterized by more oxidised compounds with hydroxyl, carbonyl, ether and/or carboxyl groups. ESI-FT-ICR-MS suggests that microbial compounds were largely aliphatic and richer in N than the background detrital material. Both molecular characterization tools suggest that CFE derived microbial biomass was largely lipid, carbohydrate and protein derived. SEC-HPLC-IRMS analysis revealed that 13C enrichment decreased with increasing MW of microbial compounds and the turnover time was deduced as 12.8 ± 0.6, 18.5 ± 0.6 and 22.9 ± 0.7 days for low, mid and high MW size classes, respectively. We conclude that low MW compounds represent the rapidly turned-over metabolite fraction of extractable soil microbial biomass consisting of organic acids, alcohols, amino acids and sugars; whereas, larger structural compounds are part of the cell envelope (likely membrane lipids, proteins or polysaccharides) with a much lower renewal rate. This relation of microbial carbon turnover to its molecular size, structure and composition thus highlights the significance of cellular biochemistry in determining the microbial contribution to soil carbon cycling and specifically soil organic matter formation.

At rest, the central nervous system combines and integrates multisensory cues to yield an optimal percept. When engaging in action, the relative weighing of sensory modalities has been shown to be altered. Because the timing of peak velocity is the critical moment in some goal-directed movements (e.g., overarm throwing), the current study sought to test whether visual and auditory cues are optimally integrated at that specific kinematic marker when it is the critical part of the trajectory.Participants performed an upper-limb movement in which they were required to reach their peak limb velocity when the right index finger intersected a virtual target (i.e., a flinging movement). Brief auditory, visual, or audiovisual feedback (i.e., 20 ms in duration) was provided to participants at peak limb velocity. Performance was assessed primarily through the resultant position of peak limb velocity and the variability of that position.Relative to when no feedback was provided, auditory feedback significantly reduced the resultant endpoint variability of the finger position at peak limb velocity. However, no such reductions were found for the visual or audiovisual feedback conditions. Further, providing both auditory and visual cues concurrently also failed to yield the theoretically predicted improvements in endpoint variability.Overall, the central nervous system can make significant use of an auditory cue but may not optimally integrate a visual and auditory cue at peak limb velocity, when peak velocity is the critical part of the trajectory.

The authors examined whether movement times (MT) for discrete saccades are constant given equivalent index of difficulty (ID) values (i.e., unitary nature of Fitts’ theorem). To that end, we contrasted ID/MT relations for saccades equated for ID but differing with respect to their target amplitudes and widths. Results showed that MT increased with increasing ID within amplitude and width conditions; however, the ID/MT slope was markedly steeper in the former condition. Thus, the amplitude condition imposed greater information processing demands than the width condition—a result indicating that the constituent elements of Fitts’ theorem are dissociable (i.e., nonunitary). Further, examination of saccade kinematics demonstrated that the optimal MT for a given target amplitude was largely independent of target width.

Particulate photocatalysts developed for the solar energy-driven reduction of the greenhouse gas CO2 have a small product range and low specificity. Hybrid photosynthesis expands the number of products with photocatalysts harvesting sunlight and transferring charges to microbes harboring versatile metabolisms for bioproduction. Besides CO2, abiotic photocatalysts have been employed to increase microbial production yields of reduced compounds from organic carbon substrates. Most single-reactor hybrid photosynthesis systems comprise CdS assembled in situ by microbial activity. This approach limits optimization of the morphology, crystal structure, and crystallinity of CdS for higher performance, which is usually done via synthesis methods incompatible with life. Here, shape and activity optimized CdS nanorods were hydrothermally produced and subsequently applied to Cupriavidus necator for the heterotrophic and autotrophic production of the bioplastic polyhydroxybutyrate (PHB). C. necator with CdS NR under light produced 1.5 times more PHB when compared to the same bacterium with suboptimal commercially-available CdS. Illuminated C. necator with CdS NR synthesized 1.41 g PHB from fructose over 120 h and 28 mg PHB from CO2 over 48 h. Interestingly, the beneficial effect of CdS NR was specific to C. necator as the metabolism of other microbes often employed for bioproduction including yeast and bacteria was negatively impacted. These results demonstrate that hybrid photosynthesis is more productive when the photocatalyst characteristics are optimized via a separated synthesis process prior to being coupled with microbes. Furthermore, bioproduction improvement by CdS-based photocatalyst requires specific microbial species highlighting the importance of screening efforts for the development of performant hybrid photosynthesis.

Hexavalent chromium (Cr(VI)) is a carcinogenic compound that can be removed from contaminated sites by the activity of metal-reducing bacteria. The model bacterium Geobacter sulfurreducens reduces Cr(VI) to less toxic Cr(III) and accumulates Cr ions intracellularly. However, this process is usually slow with small concentrations of Cr(VI) removed in a matter of days. Here, high-density G. sulfurreducens cultures were tested for the capacity to remove Cr(VI) readily. With an initial G. sulfurreducens density of 5.8 × 108 cells ml−1, 99.0 ± 0.8% of 100 mg l−1 Cr(VI) was removed after 20 min. With a higher starting Cr(VI) concentration of 200 mg l−1, G. sulfurreducens with a density of 11.4 × 108 cells ml−1 removed 99.0 ± 0.4% Cr(VI) after 2 h. Experiments performed with cell-free spent medium indicate that extracellular proteins are major contributors for the reduction of Cr(VI) to Cr(III). Furthermore, results show that most Cr(III) ions ultimately end up inside the bacterial cells where they are less susceptible to re-oxidation. The fast Cr(VI) removal rates observed with high-density G. sulfurreducens demonstrate the potential of this bacterium for bioremediation applications such as the cleaning of industrial wastewaters.

The conversion of sunlight into H2 by noble-metal-free photocatalysts is a promising approach for the production of easy-to-store chemical energy. For this purpose, higher efficiency is achieved by photocatalysts with heterojunctions preventing fast charge recombination. Most processes for the synthesis of high-performance heterojunction photocatalysts require solvents harmful to living organisms. Here, berry-shaped (b)-CdS/MoS2 particles were fabricated instead by a hydrothermal process where non-toxic bacterial cellulose was used to mold b-CdS into nanostructures with enhanced spatial arrangement. Subsequently, MoS2 was combined with b-CdS resulting in a composite with suitable shape and intimate semiconductor contacts beneficial for charge transfer. The photocatalytic H2 evolution (PHE) of b-CdS/1%MoS2 was 63.59 mmol g-1 h-1. It was 61.1 times, 397 times, and 10.2 times higher than PHE with b-CdS, CdS fabricated without BC scaffold, and b-CdS doped with Pt, respectively. These results show the high potential of b-CdS/MoS2 and the associated synthesis method for PHE.

Summary Graphene materials (GMs) are being investigated for multiple microbiological applications because of their unique physicochemical characteristics including high electrical conductivity, large specific surface area, and robust mechanical strength. In the last decade, studies on the interaction of GMs with bacterial cells appear conflicting. On one side, GMs have been developed to promote the proliferation of electroactive bacteria on the surface of electrodes in bioelectrochemical systems or to accelerate interspecies electron transfer during anaerobic digestion. On the other side, GMs with antibacterial properties have been synthesized to prevent biofilm formation on membranes for water treatment, on medical equipment, and on tissue engineering scaffolds. In this review, we discuss the mechanisms and factors determining the positive or negative impact of GMs on bacteria. Furthermore, we examine the bacterial growth-promoting and antibacterial applications of GMs and debate their practicability., Graphical Abstract, Surface Property; Microbiology; Microbiofilms

Rapid motor learning may occur in situations where individuals perceive a threat if they do not perform a task well. This rapid motor learning may be facilitated by improved motor performance and, consequently, more errorless practice. As a first step towards understanding the role of perceived threat on rapid motor learning, the purpose of this study was to determine how performance of a motor task is affected in situations where perceived threat is high. We hypothesized that perceived threat in a virtual environment would result in improved performance of a walking task (i.e., walking on a narrow beam). Results demonstrated that increased perceived threat did not yield statistically significantly greater balance performance in the high-threat virtual environment (median percentage of successful steps: 78.8%, 48.3%, and 55.2% in the real low-threat, virtual low-threat, and virtual high-threat environments, respectively). These results may be partially attributed to habituation to threat over time and practice. If implemented carefully, virtual reality technology can be an effective tool for investigating walking balance in environments that are perceived as threatening.

The selectivity of electrochemical reduction of CO2 to formate in an aqueous NaHCO3 solution was investigated with a series of trimetallic electrodes composed of different weight percentages of Sn Co coated on copper foam (Cu-f). The maximum Faradaic efficiency of 72.2% was obtained with a Sn95-Co5/Cu-f electrode at a potential of −1.36 V. The Sn95-Co5/Cu-f electrode has a formate production rate of 1.12 mmol h−1, which is 16.7, 1.2, and 2.3 times higher than uncoated Cu-f, Cu-f coated with Sn, and Cu-f coated with Co, respectively. Analysis of the surface of the Sn95-Co5/Cu-f electrode shows the formation of a composite layer of SnOx and Co3O4 ensuring good electrical conductivity and CO2 absorption. These results in combination with linear sweep voltammetry indicate that the coating of Sn Co on a porous copper scaffold resulted in the fabrication of a promising electrochemical catalyst, which can greatly increase the electrocatalysis selectivity for CO2 reduction to formate.

Long-term cognitive deficits are observed after treatment of brain tumors or metastases by radiotherapy. Treatment optimization thus requires a better understanding of the effects of radiotherapy on specific brain regions, according to their sensitivity and interconnectivity. In the present study, behavioral tests supported by immunohistology and magnetic resonance imaging provided a consistent picture of the persistent neurocognitive decline and neuroinflammation after the onset of irradiation-induced necrosis in the right primary somatosensory cortex of Fischer rats. Necrosis surrounded by neovascularization was first detected 54 days after irradiation and then spread to 110 days in the primary motor cortex, primary somatosensory region, striatum and right ventricle, resulting in fiber bundle disruption and demyelination in the corpus callosum of the right hemisphere. These structural damages translated into selective behavioral changes including spatial memory loss, disinhibition of anxiety-like behaviors, hyperactivity and pain hypersensitivity, but no significant alteration in motor coordination and grip strength abilities. Concomitantly, activated microglia and reactive astrocytes, accompanied by infiltration of leukocytes (CD45+) and T-cells (CD3+) cooperated to shape the neuroinflammation response. Overall, our study suggests that the slow and gradual onset of cellular damage would allow adaptation in brain regions that are susceptible to neuronal plasticity; while other cerebral structures that do not have this capacity would be more affected. The planning of radiotherapy, adjusted to the sensitivity and adaptability of brain structures, could therefore preserve certain neurocognitive functions; while higher doses of radiation could be delivered to brain areas that can better adapt to this treatment. In addition, strategies to block early post-radiation events need to be explored to prevent the development of long-term cognitive dysfunction.

Reaches with overlapping stimulus-response spatial relations (propointing) adhere to speed–accuracy relations as defined by Paul Fitts’ index of difficulty equation (IDFitts: in bits of information). This movement principle is attributed to response mediation via the “fast” visuomotor networks of the dorsal visual pathway. It is, however, unclear whether the executive demands of dissociating stimulus-response spatial relations by reaching mirror-symmetrical to a target (antipointing) elicits similar adherence to Fitts’ equation. Here, pro- and antipointing responses were directed to a constant target amplitude with varying target widths to provide IDFitts values of 3.0, 3.5, 4.3, and 6.3 bits. Propointing movement times linearly increased with IDFitts—a result attributed to visually based trajectory corrections. In contrast, antipointing movement times, deceleration times, and endpoint precision did not adhere to Fitts’ equation. These results indicate that antipointing renders a “slow” and offline mode of control mediated by the visuoperceptual networks of the ventral visual pathway.

Microbial electrosynthesis (MES) is a technology where a biocatalyst uses reducing equivalents generated by a bioelectrochemical system to reduce a carbon source such as CO2 into valuable products. MES reactors combine an oxidation reaction at the anode with a biological reduction reaction at the cathode. For this reason, MES can be employed for at least two applications requiring compartmentalization at the same time. For instance, a feedstock polluted by organic carbon molecules can be cleaned via biological oxidation at the anode, whereas the CO2 and reducing equivalents generated by this reaction are used at the cathode for biosynthesis purposes. This characteristic of MES also means that it can be coupled with a wide range of technologies such as anaerobic fermentation and syngas fermentation. Here, we present situations where MES could improve the profitability of several industrial bioprocesses.

International audience; Prior to goal-directed actions, somatosensory target positions can be localized using either an exteroceptive or an interoceptive body representation. The goal of the present study was to investigate if the body representation selected to plan reaches to somatosensory targets is influenced by the sensory modality of the cue indicating the target's location. In the first experiment, participants reached to somatosensory targets prompted by either an auditory or a vibrotactile cue. As a baseline condition, participants also performed reaches to visual targets prompted by an auditory cue. Gaze-dependent reaching errors were measured to determine the contribution of the exteroceptive representation to motor planning processes. The results showed that reaches to both auditory-cued somatosensory targets and auditory -cued visual targets exhibited larger gaze-dependent reaching errors than reaches to vibrotactile-cued somatosensory targets. Thus, an exteroceptive body representation was likely used to plan reaches to auditory-cued somatosensory targets but not to vibrotactile-cued somatosensory targets. The second experiment examined the influence of using an exteroceptive body representation to plan movements to somatosensory targets on pre-movement neural activations. Cortical responses to a task-irrelevant visual flash were measured as participants planned movements to either auditory-cued somatosensory or auditory -cued visual targets. Larger responses (i.e., visual-evoked potentials) were found when participants planned movements to somatosensory vs. visual targets, and source analyses revealed that these activities were localized to the left occipital and left posterior parietal areas. These results suggest that visual and visuomotor processing networks were more engaged when using the exteroceptive body representation to plan movements to somato-sensory targets, than when planning movements to external visual targets.

Microbial electrosynthesis is a bioprocess where microbes reduce CO 2 into multicarbon chemicals with electrons derived from the cathode of a bioelectrochemical reactor. Developing a highly productive microbial electrosynthesis reactor requires excellent electrical connection between the electrochemical setup, the cathode, and the microbes. Copper is a highly conductive cathode material widely employed in electrochemical apparatuses. However, the antimicrobial properties of copper limit its usage for bioelectrochemistry. Here, biocompatible reduced graphene oxide coated on copper foam is synthesized as a cathode material for the microbial electrosynthesis of acetate from CO 2 . Dense and electroactive Sporomusa ovata biofilms form on the surface of reduced graphene oxide-coated copper foam electrodes while only scattered and damaged cells cover uncoated copper electrodes. Besides the formation of metabolically-active biofilms, acetate production rate from CO 2 is 21.3 and 43.5-fold higher with this novel composite cathode compared with an uncoated copper foam cathode and a reversed cathode made of reduced graphene oxide foam coated with copper, respectively. The results demonstrate that reduced graphene oxide can be employed as a biocompatible and conductive buffer between microbes and bactericidal electrode materials with excellent electrochemical property to enable highly performant microbial electrosynthesis.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

90% of the world population is exposed to heavy atmospheric pollution. This is a major public health issue causing 7 million death each year. Air pollution comprises an array of pollutants such as particulate matters, ozone and carbon monoxide imposing a multifactorial stress on living cells. Here, Escherichia coli was used as model cell and adapted for 390 generations to atmospheric pollution to assess its long-term effects at the genetic, transcriptomic and physiological levels. Over this period, E. coli evolved to grow faster and acquired an adaptive mutation in rpoB, which encodes the RNA polymerase β subunit. Transcriptomic and biochemical characterization showed alteration of the cell membrane composition resulting in lesser permeability after the adaptation process. A second significant change in the cell wall structure of the adapted strain was the greater accumulation of the exopolysaccharides colanic acid and cellulose in the extracellular fraction. Results also indicated that amino acids homeostasis was involved in E. coli response to atmospheric pollutants. This study demonstrates that adaptive mutation with transformative physiological impact can be fixed in genome after exposure to atmospheric pollution and also provides a comprehensive portrait of the cellular response mechanisms involved.

Natural iron fertilization of high-nutrient low-chlorophyll (HNLC) waters induces annually occurring spring phytoplankton blooms off the Kerguelen Islands (Southern Ocean). To examine the origin and fate of particulate and dissolved organic matter (POM and DOM), D- and L-amino acids (AA) were quantified at bloom and HNLC stations. Total hydrolyzable AA accounted for 21–25% of surface particulate organic carbon (%POCAA) at the bloom sites, but for 10% at the HNLC site. A marked decrease in %POCAA with depth was observed at the most productive stations leading to values between 3 and 5% below 300 m depth. AA contributed to only 0.9–4.4% of dissolved organic carbon (%DOCAA) at all stations. The only consistent vertical trend was observed at the most productive station (A3-2) where %DOCAA decreased from ~ 2% in the surface waters to 0.9% near 300 m. These AA yields revealed that POM and DOM were more rapidly altered or mineralized at the bloom sites compared to the HNLC site. Alteration state was also assessed by trends in C / N ratio, %D-AA and degradation index. Different molecular markers indicated that POM mostly originated from diatoms and bacteria. The estimated average proportion of POM from intact phytoplankton cells in surface waters was 45% at the bloom station A3-2, but 14% at the HNLC site. Estimates based on D-AA yields indicated that ~ 15% of POM and ~ 30% of DOM was of bacterial origin (cells and cell fragments) at all stations. Surprisingly, the DOM in HNLC waters appeared less altered than the DOM from the bloom, had slightly higher dissolved AA concentrations, and showed no sign of alteration within the water column. Unfavorable conditions for bacterial degradation in HNLC regions can explain these findings. In contrast, large inputs of labile organic molecules and iron likely stimulate the degradation of organic matter (priming effect) and the production of more recalcitrant DOM (microbial carbon pump) during iron-fertilized blooms.

Aims To systematically evaluate the literature on interventions that improve skills retention following advanced structured resuscitation training programs designed for healthcare professionals. Methods A systematic review of MEDLINE, EMBASE, CENTRAL, CINAHL, PsycINFO, ERIC, and Scopus was performed. Only randomized controlled trials investigating skills retention following advanced structured resuscitation training programs for healthcare professionals between inception to November 21, 2018 were included. Publications that assessed only knowledge acquisition were excluded. Relevant data from included studies were extracted and study quality was critically appraised, both independently and in duplicate by multiple reviewers. The risk of bias was assessed with the Cochrane Risk of Bias tool and the Medical Education Research Study Quality Instrument (MERSQI). Due to significant clinical heterogeneity in SRT training, study designs and interventions, a qualitative synthesis was used to summarize findings. Main results Sixteen studies, with a combined total of 1192 participants, were included in the final analysis. The majority of studies were conducted in North America and involved trainees or novice learners. ACLS was the most extensively studied, followed by NRP, ALS, and ATLS. Skills retention at 6 months was the most commonly used primary endpoint assessed using a simulated resuscitation checklist with either an adopted or created assessment tool. Most studies demonstrated a positive impact on skills retention when an interactive intervention or simulation was used. However, merely having a high-fidelity mannequin alone for simulation was found to have minimal effect on skills retention in the absence of other changes in content delivery. Booster sessions were found to be minimally effective in reinforcing long-term skills retention; however, most studies examining this intervention had small sample sizes and were underpowered. Conclusions Simulation-based interventions, refresher courses and adjustments to the content delivery of advanced structured resuscitation training courses were found to have the greatest impact on skills retention. However, due to significant heterogeneity and methodological flaws in the available studies, no definitive conclusions can be made regarding other interventions. Overall, there is a paucity of skills retention research and further high-quality randomized controlled trials are needed to determine the optimal intervention and design for resuscitation training that would maximize skills retention.

International audience; When performing upper limb reaches, the sensorimotor system can adjust to changes in target location even if the reachinglimb is not visible. To accomplish this task, sensory information about the new target location and the current position of theunseen limb are used to program online corrections. Previous researchers have argued that, prior to the initiation of corrections,somatosensory information from the unseen limb must be transformed into a visual reference frame. However, mostof these previous studies involved movements to visual targets. The purpose of the present study was to determine if visualsensorimotor transformations are also necessary for the online control of movements to somatosensory targets. Participantsperformed reaches towards somatosensory and visual targets without vision of their reaching limb. Target positions wereeither stationary, or perturbed before (~ 450 ms), or after movement onset (~ 100 ms or ~ 200 ms). In response to targetperturbations after movement onset, participants exhibited shorter correction latencies, larger correction magnitudes, andsmaller movement endpoint errors when they reached to somatosensory targets as compared to visual targets. Because referenceframe transformations have been shown to increase both processing time and errors, these results indicate that handposition was not transformed into visual reference frame during online corrections for movements to somatosensory targets.These findings support the idea that different sensorimotor transformations are used for the online control of movementsto somatosensory and visual targets.

Microbial electrosynthesis (MES) is a bioelectrochemical technology developed for the conversion of carbon dioxide and electric energy into multicarbon chemicals of interest. As with other biotechnologies, achieving high production rate is a prerequisite for scaling up. In this study, we report the development of a novel cathode for MES, which was fabricated by coating carbon cloth with conductive poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) polymer. Sporomusa ovata-driven MES reactors equipped with PEDOT:PSS-carbon cloth cathodes produced 252.5 ± 23.6 mmol d−1 acetate per m2 of electrode over a period of 14 days, which was 9.3 fold higher than the production rate observed with uncoated carbon cloth cathodes. Concomitantly, current density was increased to −3.2 ± 0.8 A m−2, which was 10.7-fold higher than the untreated cathode. The coulombic efficiency with the PEDOT: PSS-carbon cloth cathodes was 78.6 ± 5.6%. Confocal laser scanning microscopy and scanning electron microscopy showed denser bacterial population on the PEDOT:PSS-carbon cloth cathodes. This suggested that PEDOT:PSS is more suitable for colonization by S. ovata during the bioelectrochemical process. The results demonstrated that PEDOT: PSS is a promising cathode material for MES

A major challenge to the measurement of online control is the contamination by offline, planning-based processes. The current study examined the sensitivity of four measures of online control to offline changes in reaching performance induced by prism adaptation and terminal feedback. These measures included the squared Z scores (Z2) of correlations of limb position at 75% movement time versus movement end, variable error, time after peak velocity, and a frequency-domain analysis (pPower). The results indicated that variable error and time after peak velocity were sensitive to the prism adaptation. Furthermore, only the Z2 values were biased by the terminal feedback. Ultimately, the current study has demonstrated the sensitivity of limb kinematic measures to offline control processes and that pPower analyses may yield the most suitable measure of online control.

Microbes can reduce CO2 into multicarbon chemicals with electrons acquired from the cathode of a bioelectrochemical reactor. This bioprocess is termed microbial electrosynthesis (MES). One of the main challenges for the development of highly productive MES reactors is achieving efficient electron transfer from the cathode to microbes. Here, carbon cloth cathodes modified with reduced graphene oxide functionalized with tetraethylene pentamine (rGO-TEPA) were readily self-assembled in the cathodic chamber of a MES reactor. Electroactive biofilms with unique spatial arrangement were subsequently formed with Sporomusa ovata at the surface of rGO-TEPA-modified electrodes resulting in a more performant MES process. The acetate production rate from CO2 was increased 3.6 fold with the formation of dense biofilms when wild type S. ovata was combined with rGO-TEPA. An improvement of 11.8 fold was observed with a highly structured biofilm including multiple spherical structures possibly consisting of bioinorganic networks of rGO-TEPA and bacterial cells from a novel strain of S. ovata adapted to reduce CO2 faster. The three dimensional biofilms observed in this study enabled highly effective electric interactions between S. ovata and the cathode, demonstrating that the development of dense cathode biofilms is an effective approach to improve MES productivity.

The utilization of sensory information during activities of daily living is ubiquitous both prior to and during movements (i.e., related to planning and online control, respectively). Because of the overlapping nature of online corrective processes, the quantification of feedback utilization has proven difficult. In the present study, we primarily sought to evaluate the utility of a novel analysis in the frequency domain for identifying visuomotor feedback utilization (i.e., online control). A second goal was to compare the sensitivity of the frequency analysis to that of currently utilized measures of online control. Participants completed reaching movements to targets located 27, 30, and 33 cm from a start position. During these reaches, vision of the environment was either provided or withheld. Performance was assessed across contemporary measures of online control. For the novel frequency analysis presented in this study, the acceleration profiles of reaching movements were detrended with a 5th-order polynomial fit, and the proportional power spectra were computed from the residuals of these fits. The results indicated that the use of visual feedback during reaching movements increased the contribution of the 4.68-Hz frequency to the residuals of the acceleration profiles. Comparisons across all measures of online control showed that the most sensitive measure was the squared Fisher transform of the correlation between the positions at 75 % and 100 % of the movement time. However, because such correlational measures can be contaminated by offline control processes, the frequency-domain analysis proposed herein represents a viable and promising alternative to detect changes in online feedback utilization.

Presenting target and non-target information in different modalities influences target localization if the non-target is within the spatiotemporal limits of perceptual integration. When using auditory and visual stimuli, the influence of a visual non-target on auditory target localization is greater than the reverse. It is not known, however, whether or how such perceptual effects extend to goal-directed behaviours. To gain insight into how audio-visual stimuli are integrated for motor tasks, the kinematics of reaching movements towards visual or auditory targets with or without a non-target in the other modality were examined. When present, the simultaneously presented non-target could be spatially coincident, to the left, or to the right of the target. Results revealed that auditory non-targets did not influence reaching trajectories towards a visual target, whereas visual non-targets influenced trajectories towards an auditory target. Interestingly, the biases induced by visual non-targets were present early in the trajectory and persisted until movement end. Subsequent experimentation indicated that the magnitude of the biases was equivalent whether participants performed a perceptual or motor task, whereas variability was greater for the motor versus the perceptual tasks. We propose that visually induced trajectory biases were driven by the perceived mislocation of the auditory target, which in turn affected both the movement plan and subsequent control of the movement. Such findings provide further evidence of the dominant role visual information processing plays in encoding spatial locations as well as planning and executing reaching action, even when reaching towards auditory targets.

Adam, Mol, Pratt, and Fischer (2006) reported what they termed “a violation of Fitts’s Law” – when participants aimed to targets in an array, movement times (MTs) to the last target location (highest index of difficulty (ID)) were shorter than predicted by Fitts’s Law. Based on the results of subsequent studies in which placeholders were present either during planning and/or execution stages of the movements, it was suggested that the violation may emerge because of context-dependent changes in planning processes. The present study examined this planning explanation by conducting detailed kinematic analyses of movements. Participants performed aiming movements to sets of 3 targets in different placeholder arrays with different movement amplitudes. Consistent with previous Fitts’s Law violation findings, MTs were not significantly longer for movements to the last versus middle target location. Interestingly, the pattern of peak limb velocities (typically associated with planning processes) did not mirror the changes in MTs. On the other hand, analyses of the effector’s spatial variability during the movement suggested greater involvement of online control processes when the target was in the last position. Based on these results, we suggest that the Fitts’ Law violation observed here occurred because of more efficient online control processes.

Adaptive laboratory evolution (ALE) is an approach enabling the development of novel characteristics in microbial strains via the application of a constant selection pressure. This method is also an efficient tool to acquire insights on molecular mechanisms responsible for specific phenotypes. ALE experiments have mainly been conducted with heterotrophic microbes to study, for instance, cell metabolism with different multicarbon substrates, tolerance to solvents, pH variation, and high temperature. Here, we describe employing an ALE method to generate Sporomusa ovata strains growing faster autotrophically and reducing CO2 into acetate more efficiently. Strains developed via this ALE method were also used to gain knowledge on the autotrophic metabolism of S. ovata as well as other acetogenic bacteria.

Ideomotor theory states that the neural codes that represent action and the perceptual consequences of those actions are tightly bound in a common code. For action imagination, bound action, and perceptual codes are thought to be internally activated at a sub-threshold level through action simulation. In support of this hypothesis, previous research revealed that imagined movement times (MTs) for reciprocal aiming movements were closer to actual execution MTs after the participants gained experience executing the task. The current study examined the task-specific nature of the effects of experience on imagination by determining if improvements in accuracy in the imagination of reciprocal aiming movements occur only with experience of the reciprocal aiming task or with any aiming task. To this end, one group of participants executed a reciprocal pointing task, whereas a second group executed a discrete aiming task with comparable accuracy requirements before and after imagining reciprocal aiming movements. Influence of task specificity on imagination was assessed by evaluating the changes in imagined MTs before and after execution. Consistent with previous findings, there was a reduction in imagined MTs following task execution. Critically, there was a significant time by group interaction revealing a significant pre/post reduction in imagined MTs for the group that executed the reciprocal aiming movements, but not for the group that executed the discrete aiming movements. These data support ideomotor accounts of action imagination because it appears that the imagination of a movement is affected by task-specific experience with that movement.

Background We investigate the use of different denoising filters on low signal-to-noise ratio cardiac images of the rat heart acquired with a birdcage volume coil at 7T. Accuracy and variability of cardiac function parameters were measured from manual segmentation of rat heart images with and without filtering. Methods Ten rats were studied using a 7T Varian system. End-diastolic and end-systolic volumes, ejection fraction and left ventricle mass (LVM) were calculated from manual segmentation by two experts on cine-FLASH short-axis slices covering the left ventricle. Series were denoised with an anisotropic diffusion filter, a whole variation regularization or an optimized Rician non-local means (ORNLM) filtering technique. The effect of the different filters was evaluated by the calculation of signal-to-noise (SNR) and contrast-to-noise (CNR) ratios, followed by a study of intra- and inter-expert variability of the measurement of physiological parameters. The calculated LVM was compared to the LVM obtained by weighing the heart ex vivo. Results The SNR and the CNR increased after application of the different filters. The performance of the ORNLM filter was superior for all the parameters of the cardiac function, as judged from the inter- and intra-observer variabilities. Moreover, this filtering technique resulted in the lowest variability in the LVM evaluation. Conclusions In cardiac MRI of rats, filtering is an interesting alternative that yields better contrast between myocardium and surrounding tissues and the ORNLM filter provided the largest improvements.

Adaptive laboratory evolution (ALE) is an approach enabling the development of novel characteristics in microbial strains via the application of a constant selection pressure. This method is also an efficient tool to acquire insights on molecular mechanisms responsible for specific phenotypes. ALE experiments have mainly been conducted with heterotrophic microbes to study, for instance, cell metabolism with different multicarbon substrates, tolerance to solvents, pH variation, and high temperature. Here, we describe employing an ALE method to generate Sporomusa ovata strains growing faster autotrophically and reducing CO

The technique of plasma coating emerged in the seventies as a novel and versatile approach to modifying the surface chemistry of a wide range of materials. Chawla developed plasma polymerized silicone coatings and Garfinkle and Hoffman demonstrated that polyester vascular prostheses treated with tetrafluoroethylene plasma yield dramatic improvements in the resistance to thrombus formation and emboli. Atrium Medical Corporation has produced a Plasma TFE® tubular woven polyester blood conduit, whose internal surface has been treated with fluoropolymer. The absence of crimps and the inclusion of a helically wound external support suggests that this device heralds a new generation of woven polyester vascular prostheses. This study reports the results of an in vitro evaluation of this new product. A unique feature of the Plasma TFE® graft is that it contains texturized yarns in the warp direction and flat multifilament yarns in the weft direction. Such a mixture is not usually found in commercial prostheses, and results in the graft’s unique characteristic of expanding at low pressures of less than 50mm Hg, and then exhibiting minimal increases in diameter at internal pressures above 80 mm Hg. Because of the absence of crimps, the elongation of this graft is about half the value for the Woven DeBakey Soft, the least extensible commercial woven control. While the bursting strength is comparable to other woven prostheses, the average water permeability value of 180 ml/cm2/min/120 mm Hg is considerably higher than the value of 100 quoted in the manufacturer’s literature. The suture retention strength results highlight the high frequency of prosthesis rather than the suture breaks and indicate that the suture retention performance can be improved by cutting with a cautery instead of scissors. Surface analysis by ESCA, solvent extraction and differential dyeing demonstrate that the flow surface of the prosthesis contains a non-uniform plasma coating and a high level of extractable contaminants.

Microbial electrosynthesis (MES) is a promising technology for the reduction of carbon dioxide into value-added multicarbon molecules. In order to broaden the product profile of MES processes, we developed a two-stage process for microbial conversion of carbon dioxide and electricity into long chain alkyl esters. In the first stage, the carbon dioxide is reduced to organic compounds, mainly acetate, in a MES process by Sporomusa ovata. In the second stage, the liquid end-products of the MES process are converted to the final product by a second microorganism, Acinetobacter baylyi in an aerobic bioprocess. In this proof-of-principle study, we demonstrate for the first time the bacterial production of long alkyl esters (wax esters) from carbon dioxide and electricity as the sole sources of carbon and energy. The process holds potential for the efficient production of carbon-neutral chemicals or biofuels. acceptedVersion

The biological reduction of CO2 driven by sunlight via photosynthesis is a crucial process for life on earth. However, the conversion efficiency of solar energy to biomass by natural photosynthesis is low. This translates in bioproduction processes relying on natural photosynthesis that are inefficient energetically. Recently, hybrid photosynthetic technologies with the potential of significantly increasing the efficiency of solar energy conversion to products have been developed. In these systems, the reduction of CO2 into biofuels or other chemicals of interest by biocatalysts is driven by solar energy captured with inorganic devices such as photovoltaic cells or photoelectrodes. Here, we explore hybrid photosynthesis and examine the strategies being deployed to improve this biotechnology.

The authors investigated how visual information from the nondominant and dominant eyes are utilized to control ongoing dominant hand movements. Across 2 experiments, participants performed upper-limb pointing movements to a stationary target or an imperceptibly shifted target under monocular-dominant, monocular-nondominant, and binocular viewing conditions. Under monocular-dominant viewing conditions, participants exhibited better endpoint precision and accuracy. On target jump trials, participants spent more time after peak limb velocity and significantly altered their trajectories toward the new target location only when visual information from the dominant eye was available. Overall, the results suggest that the online visuomotor control processes that typically take place under binocular viewing conditions are significantly influenced by input from the dominant eye.

The role of hypervalent iodine reagents as oxidants has been widely recognized for more than 20 years. As electrophilic species, they could also play the role of Lewis acids. While not surprising, this aspect of these reagents has not been fully considered and exploited in the literature. The experimental quantification of the Lewis acidity of a small series of diaryliodonium salts was performed using the Gutmann–Beckett method. Validation of a theoretical model using the experimental data was done in order to predict the Lewis acidity of other cationic iodine(III) species. Comparison with known common Lewis acids is presented.

During microbial electrosynthesis (MES) driven CO2 reduction, cathode plays a vital role by donating electrons to microbe. Here, we exploited the advantage of reduced graphene oxide (RGO) paper as novel cathode material to enhance electron transfer between the cathode and microbe, which in turn facilitated CO2 reduction. The acetate production rate of Sporomusa ovata-driven MES reactors was 168.5 ± 22.4 mmol m−2 d−1 with RGO paper cathodes poised at −690 mV versus standard hydrogen electrode. This rate was approximately 8 fold faster than for carbon paper electrodes of the same dimension. The current density with RGO paper cathodes of 2580 ± 540 mA m−2 was increased 7 fold compared to carbon paper cathodes. This also corresponded to a better cathodic current response on their cyclic voltammetric curves. The coulombic efficiency for the electrons conversion into acetate was 90.7 ± 9.3% with RGO paper cathodes and 83.8 ± 4.2% with carbon paper cathodes, respectively. Furthermore, more intensive cell attachment was observed on RGO paper electrodes than on carbon paper electrodes with confocal laser scanning microscopy and scanning electron microscopy. These results highlight the potential of RGO paper as a promising cathode for MES from CO2.

Visual feedback is crucial for movement accuracy (e.g., Keele and Posner, J Exp Psychol 77:155–158, 1968). As well, proprioception has been argued to be important for the control of voluntary movements (e.g., Bagesteiro et al., Exp Brain Res 171:358–370, 2006; Rossetti et al., J Neurophysiol 74:457–463, 1995). While tendon vibration (TVib) has been used to perturb proprioceptive information during limb matching tasks (Goodwin et al., Science 175:1382–1384, 1972), the current study employed between-trial dual-muscle TVib, coupled with vision occlusion, to assess the use of vision and proprioception for the online control of voluntary movements. Participants (n = 17) performed an upper-limb reaching task (30 cm). TVib influenced both accuracy and precision of movement endpoint. Critically, variability analyses showed that participant’s performance was most affected by TVib at 75% of the movement duration, even in the presence of vision. These findings demonstrate that between-trial dual-muscle tendon vibration can perturb proprioceptive feedback, and further, suggest that proprioception can be important for the online control of reaches, even when vision is available.

The commentary by Errol Hoffmann asserts that previous work by our group provides the spurious conclusion that amplitude and width manipulations to a movement environment elicit dissociable relations between movement time (MT) and P. M. Fitts' (1954) index of difficulty (ID). Hoffmann concludes that any such dissociation is the result of actions evoked entirely as ballistic. In this reply, we demonstrate that Hoffmann's commentary is a clear misrepresentation of the study goals and conclusions stated by our group. Additionally, we provide kinematic evidence that actions involving online trajectory amendments are associated with dissociable MT-ID relations for amplitude versus width manipulations. Finally, we contend that the kinematic analyses of movement trajectories, and Hoffmann's failure to acknowledge its importance, is an important step in further understanding speed-accuracy relations in human movement.

In this article, I argue that there are two distinct conceptions of the principle of proportionality within constitutional law and theory. One comes within what I call “the priority of rights model” and the other within what I call “the model of optimization of values in conflict.” The main purpose of the text is to propound an egalitarian defense of proportionality-based balancing, such as it is understood within the model of optimization. After having described the “idealtype” of each model (Section 2), I argue that the normative justification of the model of optimization lies in the fact that it honors the moral equality of persons in context of pluralism and cultural diversity (Section 3). In particular, I argue that, from this normative point of view, the priority of rights model has become difficult to sustain. The argument is a form of “ethical proceduralism”: it refers to a procedure by virtue of which the normative validity of the competing models is tested.

The goal of this work was to develop amino acid (AA) quantification protocols using simple sample preparation steps and new chromatographic conditions optimized for a hybrid (organo-silica) C18 column resistant to alkaline samples in borate buffer. This resistance allows for larger injection volumes, and thus stronger detected signals (~3 times stronger), higher precision, and lower analysis costs compared with previous methods. Enantiomeric and non-enantiomeric separations of AA were possible in less than 0.5 mL of AA-poor water samples. Results showed that a high salt content and the sample treatment do not lead to AA loss or separation interference. The accuracy and the precision of AA quantification in a natural sample strongly depend on the blank correction. The limits of detection, measured based on the variability of these blanks, were 0.007–3.6 nM depending on the AA. The protocols developed here allow for the quantification of all forms of AA (i.e., free, dissolved combined, particulate, and total) in most natural waters, including deep ocean waters. It was even possible to quantify many AA in ultrapure water after blank correction. Despite the injection of a relatively high volume (100 µL) of alkaline borate solutions, the hybrid C18 column showed no sign of performance degradation after more than 700 injections. This durability reduces the cost of AA analysis and provides a more consistent separation. The analysis time can be greatly reduced by the use of stationary phases with a nonporous core and extended pH stability as they become available.

Purpose The combination of MRI and positron emission tomography (PET) offers new possibilities for the development of novel methodologies. In pharmacokinetic image analysis, the blood concentration of the imaging compound as a function of time, [i.e., the arterial input function (AIF)] is required for MRI and PET. In this study, we tested whether an AIF extracted from a reference region (RR) in MRI can be used as a surrogate for the manually sampled 18F-FDG AIF for pharmacokinetic modeling. Methods An MRI contrast agent, gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) and a radiotracer, 18F-fluorodeoxyglucose (18F-FDG), were simultaneously injected in a F98 glioblastoma rat model. A correction to the RR AIF for Gd-DTPA is proposed to adequately represent the manually sampled AIF. A previously published conversion method was applied to convert this AIF into a 18F-FDG AIF. Results The tumor metabolic rate of glucose (TMRGlc) calculated with the manually sampled 18F-FDG AIF, the 18F-FDG AIF converted from the RR AIF and the 18F-FDG AIF converted from the corrected RR AIF were found not statistically different (P > 0.05). Conclusion An AIF derived from an RR in MRI can be accurately converted into a 18F-FDG AIF and used in PET pharmacokinetic modeling. Magn Reson Med 73:740–748, 2015. © 2014 Wiley Periodicals, Inc.

BACKGROUND: Brain metastases (BM) are the most prevalent intracranial neoplasm. Inflammation is central to the development of cancer. While an intra-tumoral inflammatory microenvironment contributes to the acquisition of malignant phenotypes and leads to the release of circulating tumor cells (CTCs), pre-existing inflammation at distant sites facilitates the adhesion of CTCs to the activated vascular endothelium and the consequent formation of metastases. Cell adhesion molecules expressed by activated endothelial cells contribute to metastatic spread outside of the brain and the vascular cell adhesion molecule-1 (VCAM-1) is a key mediator of inflammation. Herein we assessed if cancer cells entry into the brain is aided by VCAM-1 upregulation with inflammation. METHODS: Stereotaxic lipopolysaccharide (LPS, 1 µg) injection into the right hemisphere was used to induce neurovascular inflammation in Balb/c mice. The distribution of VCAM-1 was semi-quantified 24 h post LPS injection using molecular magnetic resonance imaging (MRI) with microparticles of iron oxide (MPIOs) functionalized with VCAM-1 antibody (MPIO-VCAM-1). Mice injected with saline served as control. VCAM-1 is also expressed on vessels associated with metastases, MPIO-VCAM-1 were therefore used to detect metastases. Basal level of metastases in animal brains was measured in a group of mice intracardially injected with cancer cells without LPS intra-cortical injection. To study the impact of pre-existing inflammation on tumor cell entry into the brain, mice were injected with LPS (or saline as above) 24 h prior to intracardiac injection of 4T1 breast cancer cells (105 cells in 100 µL PBS). Metastases imaging was performed 18 days post cancer cells injection. To assess if blocking VCAM-1 would affect metastases implantation, an extra LPS-injected group of mice was injected intravenously with MPIO-VCAM-1 4 hours before 4T1 cells injection. In this group, MRI was performed 3 hours after MPIO-VCAM-1 injection (VCAM-1 imaging), and on day 18 post tumor cell injection (metastases imaging). All MRI experiments were conducted on a small animal 7T scanner (Varian Inc.) with a dedicated mouse head-coil (RAPID MR International) using a T2*-weighted sequence. Following the final imaging session brains were extracted for histological analysis. RESULTS: Both MR and histological data reveal that the metastatic burden significantly increases in the LPS-injected group compared to control conditions. In inflamed animals, blocking VCAM-1 with MPIO-VCAM-1 reduces the metastatic burden back to control values. This suggests that (1) a pre-existing inflammation increases the occurrence of brain metastases and (2) blocking VCAM-1 reduces this effect. CONCLUSION: We demonstrate that inflammation-induced VCAM-1 contributes to tumor cells adhesion in the brain. Therefore, VCAM-1 may represent an attractive therapeutic target to reduce risks of metastasis. Citation Format: Dina Sikpa, Lisa Whittingstall, Jérémie P. Fouquet, Luc Tremblay, Réjean Lebel, Martin Lepage. Pre-existing neurovascular inflammation increases the occurrence of brain metastases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 86.