Physiological evaluation of yeast strains under anaerobic conditions using glucose, fructose, or sucrose as the carbon source.

The aim of this study was to evaluate the physiology of 13 yeast strains by assessing their kinetic parameters under anaerobic conditions. They included Saccharomyces cerevisiae CAT-1 and 12 isolated yeasts from different regions in Brazil. The study aimed to enhance understanding of the metabolism of these strains for more effective applications. Measurements included quantification of sugars, ethanol, glycerol, and organic acids. Various kinetic parameters were analyzed, such as specific substrate utilization rate (qS), maximum specific growth rate (µmax), doubling time, biomass yield, product yield, maximum cell concentration, ethanol productivity (PEth), biomass productivity, and CO2 concentration. S. cerevisiae CAT-1 exhibited the highest values in glucose for µmax (0.35 h-1), qS (3.06 h-1), and PEth (0.69 gEth L-1 h-1). Candida parapsilosis Recol 37 did not fully consume the substrate. In fructose, S. cerevisiae CAT-1 stood out with higher values for µmax (0.25 h-1), qS (2.24 h-1), and PEth (0.60 gEth L-1 h-1). Meyerozyma guilliermondii Recol 09 and C. parapsilosis Recol 37 had prolonged fermentation times and residual substrate. In sucrose, only S. cerevisiae CAT-1, S. cerevisiae BB9, and Pichia kudriavzevii Recol 39 consumed all the substrate, displaying higher PEth (0.72, 0.51, and 0.44 gEth L-1 h-1, respectively) compared to other carbon sources.

Fast updating feedback from piriform cortex to the olfactory bulb relays multimodal reward contingency signals during rule-reversal.

While animals readily adjust their behavior to adapt to relevant changes in the environment, the neural pathways enabling these changes remain largely unknown. Here, using multiphoton imaging, we investigated whether feedback from the piriform cortex to the olfactory bulb supports such behavioral flexibility. To this end, we engaged head-fixed mice in a multimodal rule-reversal task guided by olfactory and auditory cues. Both odor and, surprisingly, the sound cues triggered cortical bulbar feedback responses which preceded the behavioral report. Responses to the same sensory cue were strongly modulated upon changes in stimulus-reward contingency (rule reversals). The re-shaping of individual bouton responses occurred within seconds of the rule-reversal events and was correlated with changes in the behavior. Optogenetic perturbation of cortical feedback within the bulb disrupted the behavioral performance. Our results indicate that the piriform-to-olfactory bulb feedback carries reward contingency signals and is rapidly re-formatted according to changes in the behavioral context.

Laparoscopy with augmented reality adaptations.

One of the most promising applications of Optical See-Through Augmented Reality is minimally laparoscopic surgery, which currently suffers from problems such as surgeon discomfort and fatigue caused by looking at a display positioned outside the surgeon's visual field, made worse by the length of the procedure. This fatigue is especially felt on the surgeon's neck, as it is strained from adopting unnatural postures in order to visualise the laparoscopic video feed. Throughout this paper, we will present work in Augmented Reality, as well as developments in surgery and Augmented Reality applied to both surgery in general and laparoscopy in particular to address these issues. We applied user and task analysis methods to learn about practices performed in the operating room by observing surgeons in their working environment in order to understand, in detail, how they performed their tasks and achieved their intended goals. Drawing on observations and analysis of video recordings of laparoscopic surgeries, we identified relevant constraints and design requirements. Besides proposals to approach the ergonomic issues, we present a design and implementation of a multimodal interface to enhance the laparoscopic procedure. Our method makes it more comfortable for surgeons by allowing them to keep the laparoscopic video in their viewing area regardless of neck posture. Also, our interface makes it possible to access patient imaging data without interrupting the operation. It also makes it possible to communicate with team members through a pointing reticle. We evaluated how surgeons perceived the implemented prototype, in terms of usefulness and usability, via a think-aloud protocol to conduct qualitative evaluation sessions which we describe in detail in this paper. In addition to checking the advantages of the prototype as compared to traditional laparoscopic settings, we also conducted a System Usability Scale questionnaire for measuring its usability, and a NASA Task Load Index questionnaire to rate perceived workload and to assess the prototype effectiveness. Our results show that surgeons consider that our prototype can improve surgeon-to-surgeon communication using head pose as a means of pointing. Also, surgeons believe that our approach can afford a more comfortable posture throughout the surgery and enhance hand-eye coordination, as physicians no longer need to twist their necks to look at screens placed outside the field of operation.