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Middle school brings rapid developmental changes for adolescents, and parent engagement is as essential as ever. However, what worked for parent-teacher partnerships in elementary school doesn’t fit so well in middle school. Adolescents are building their autonomy, and teachers must help empower parents’ efforts to bolster students as independent learners through academic socialization. The authors explore how a brief texting intervention might build trust between teachers and parents, empower parents to support their children, and contribute to students’ confidence and belonging in school. Results indicate that brief communications sent by text may bolster parent engagement efforts in middle school.

Zooplankton communities are typically comprised of smaller-bodied species when size-selective fish predators are abundant, but become dominated by large-bodied species when fish predators are scarce. Superiority by larger-bodied grazers over smaller-bodied species in competition for algal resources has been proposed to be the mechanism responsible for this observed pattern. To investigate this mechanism, we performed a laboratory experiment with two freshwater zooplankton species, the larger-bodied Daphnia pulicaria and smaller-bodied D. mendotae, obtained from Square Lake (Washington County, Minnesota). The Daphnia species were grown in monoculture and in combination over a 24-day period to assess the outcome of competition between the two species and their effect on algae cell densities. We hypothesized that the larger-bodied D. pulicaria species would outcompete D. mendotae, and that D. pulicaria would exert greater control on algae levels than would D. mendotae. Results of the experiment strongly supported these hypotheses, and were consistent with findings of a recently completed field study of Square Lake that discovered that terminating the program of stocking rainbow trout (a zooplanktivorous predator) in the lake resulted in D. pulicaria replacing D. mendotae as the dominant Daphnia species and in the reduction of algae levels in the lake's surface waters.

Debaryomyces hansenii is traditionally described as a halotolerant non-conventional yeast and has served as a model organism for the study of osmotolerance and salt tolerance mechanisms in eukaryotic systems for the past 30 years. However, unraveling of D. hansenii's biotechnological potential has always been difficult due to the persistent limitations in the availability of efficient molecular tools described for this yeast. Additionally, there is a lack of consensus and contradictory information along the recent years that limits a comprehensive understanding of its central carbon metabolism, mainly due to a lack of physiological studies in controlled and monitored environments. Moreover, there is little consistency in the culture conditions (media composition, temperature, and pH among others) used by different groups, which makes it complicated when trying to get prevalent conclusions on behavioral patterns. In this work, we present for the first time a characterization of D. hansenii in batch cultivations using highly controlled lab-scale bioreactors. Our findings contribute to a more complete picture of the central carbon metabolism and the external pH influence on the yeast's ability to tolerate high Na+ and K+ concentrations, pointing to a differential effect of both salts, as well as a positive effect in cell performance when low environmental pH values are combined with a high sodium concentration in the media. Finally, a novel survival strategy at very high salinity (2 M) is proposed for this yeast, as well as potential outcomes for its use in industrial biotechnology applications. TAKE AWAY: High salt concentrations stimulate respiration in Debaryomyces hansenii. Sodium exerts a stronger positive impact on cell performance than potassium. μmax is higher at a combination of low pH, high salt, and high temperature. Concentrations of 2 M salt result in slower growth but increased biomass yield. The positive effect of salts is enhanced at low glucose concentration.

With the increasing demand for blood transfusions, the production of human hemoglobin (Hb) from sustainable sources is increasingly studied. Microbial production is an attractive option, as it may provide a cheap, safe, and reliable source of this protein. To increase the production of human hemoglobin by the yeast Saccharomyces cerevisiae, the degradation of Hb was reduced through several approaches. The deletion of the genes HMX1 (encoding heme oxygenase), VPS10 (encoding receptor for vacuolar proteases), PEP4 (encoding vacuolar proteinase A), ROX1 (encoding heme-dependent repressor of hypoxic genes) and the overexpression of the HEM3 (encoding porphobilinogen deaminase) and the AHSP (encoding human alpha-hemoglobin-stabilizing protein) genes — these changes reduced heme and Hb degradation and improved heme and Hb production. The reduced hemoglobin degradation was validated by a bilirubin biosensor. During glucose fermentation, the engineered strains produced 18% of intracellular Hb relative to the total yeast protein, which is the highest production of human hemoglobin reported in yeast. This increased hemoglobin production was accompanied with an increased oxygen consumption rate and an increased glycerol yield, which (we speculate) is the yeast's response to rebalance its NADH levels under conditions of oxygen limitation and increased protein-production.

Debaryomyces hansenii is traditionally described as a halotolerant non-conventional yeast, being the model organism for the study of osmo- and salt tolerance mechanisms in eukaryotic systems for the past 30 years.However, unravelling of D. hansenii’s biotechnological potential has always been difficult due to the persistent limitations in the availability of efficient molecular tools described for this yeast. Additionally, there is a lack of consensus and contradictory information along the recent years that limits a comprehensive understanding of its central carbon metabolism, mainly due to a lack of physiological studies in controlled and monitored environments. Moreover, there is controversy about the diversity in the culture conditions (media composition, temperature and pH among others) used by different groups, which makes it complicated when trying to get significant conclusions and behavioural patterns.In this work, we present for the first time a physiological characterization of D. hansenii in batch cultivations using highly instrumented and controlled lab-scale bioreactors. Our findings contribute to a more complete picture of the central carbon metabolism and the external pH influence on the yeast ability to tolerate high Na+ and K+ concentrations. Finally, the controversial halophilic/halotolerant character of this yeast is further clarified.

We evaluated the response of a remnant population of yellow-bellied marmots (Marmota flaviventris) to targeted habitat enhancement in an ecological system that had been degraded during ~100 years of intensive livestock management, including marmot eradication. We used capture-recapture data and a novel use of a multistate framework to evaluate geographic expansion of the marmot population pre- and post-habitat enhancement. We also estimated age-structured survival, reproduction, and sex ratios. The marmot population appeared to respond positively to new habitat opportunities created by habitat enhancement: the number of marmots captured increased from three marmots pre-habitat enhancement to 54 (28 adults and yearlings, 26 young) post-habitat enhancement at the end of the study. Marmots expanded geographically by transitioning into habitat-enhanced areas, and adult females occupied and reproduced in all habitat-enhanced areas. The sex ratio of the young population in 2019 was strongly female-biased, which may have been influenced by poor body condition of breeding females owing to unusually prolonged snow cover that year. Adult and yearling survival were within the range of that reported for colonial adults and yearlings in Colorado. Our results suggest that active habitat enhancement can assist in the recovery of marmot populations in systems where marmots historically existed.

Automated fiber placement provides many advancements beyond traditional hand layups in terms of efficiency and reliability. However, there are also a variety of unique challenges that arise with automated fiber placement technology. In particular, steering of tows over doubly-curved tool surfaces can result in material overlaps and gaps due to path convergence/divergence, fiber angle deviation, as well defects in the tows themselves such as puckers and wrinkles. Minimization of these defects is traditionally considered a task for the manufacturing discipline. Manufacturing specifications are often created for these defects based on laminate testing and can be inflexible to avoid more tests. Recent efforts have been made under the National Aeronautics and Space Administration (NASA) Advanced Composites Project (ACP) to develop software tools and processes that provide automated coupling between design and manufacturing disciplines. The objective of this coupling is to provide information to the design discipline on the manufacturability of a laminate while the laminate is being designed. A variety of software tools, both existing commercial tools and research tools under development, will be used to achieve this objective: HyperSizer for laminate optimization, the Computer Aided Process Planning module for selection of manufacturing process parameters, Vericut Composite Programming for tow path simulation, and COMPRO for deposition and cure defects. The newly developed “Central Optimizer” tool will be used to tie the modules together and drive the design for manufacturing process.

Existing design processes for laminates constructed with automated fiber placement lack significant integration between the various software tools that compose the process. Tools for finite element analysis, computer aided drafting, stress analysis, tool path simulation, and manufacturing defect prediction are all critical parts of the design process. With traditional hand-layup laminates, the analysis performed with each of these tools could be fairly well decoupled from one another. However, for laminates generated by automated fiber placement, the disciplines can become significantly coupled, especially on structures with curvature. This gives rise to a need for integrated “design for manufacturing” software tools that are able to balance the competing objectives from each discipline. This paper describes the preliminary development of such a tool.