In rats, whisking behavior is characterized by high-frequency synchronous movements and other stereotyped patterns of bilateral coordination that are rarely seen in the bilateral movements of the limbs. This suggests that the motor systems controlling whisker and limb movements must have qualitative or quantitative differences in their interhemispheric connections. To test this hypothesis, anterograde tracing methods were used to characterize the bilateral distribution of projections from the whisker and forepaw regions in the primary motor (MI) cortex. Unilateral tracer injections in the MI whisker or forepaw regions revealed robust projections to the corresponding MI cortical area in the contralateral hemisphere. Both MI regions project bilaterally to the neostriatum, but the corticostriatal projections from the whisker region are denser and more evenly distributed across both hemispheres than those from the MI forepaw region. The MI whisker region projects bilaterally to several nuclei in the thalamus, whereas the MI forepaw region projects almost exclusively to the ipsilateral thalamus. The MI whisker region sends dense projections to the contralateral claustrum, but those to the ipsilateral claustrum are less numerous. By contrast, the MI forepaw region sends few projections to the claustrum of either hemisphere. Bilateral deposits of different tracers in MI revealed overlapping projections to the neostriatum, thalamus, and claustrum when the whisker regions were injected, but not when the forepaw regions were injected. These results suggest that the bilateral coordination of the whiskers depends, in part, on MI projections to the contralateral neostriatum, thalamus, and claustrum.

Combinatorial pretreatments with a low holding temperature were developed in an effort to synergistically improve the carbohydrate output and lignin processability from corn stover.

Researchers have assessed relational aggression (RA) and physical aggression (PA) primarily with teacher ratings and peer nominations. However, limited observational research exists in this area. This study compared three methods for assessing RA and PA: a teacher rating scale, a peer nomination measure, and a direct observation measure. Results supported previous research showing intermethod agreement between peer and teacher ratings of RA for girls and PA for boys. All three methods indicated that boys engaged in PA and RA more often than girls. However, teachers and peers agreed more often about incidences of RA and PA than did observers. Thus, a variety of evaluation tools may be necessary to assess preschoolers' types of aggression. Development of accurate, practical measures will provide educators with better identification, prevention, and intervention strategies for boys and girls.

Rat whisking behavior is characterized by high amounts of bilateral coordination in which whisker movements on both sides of the face are linked. To elucidate the neural substrate that might mediate this bilateral coordination, neuronal tracers were used to characterize the bilateral distribution of corticothalamic projections from primary motor (MI) cortex. Some rats received tracers in the MI whisker region, whereas others received tracers in the MI forepaw region. The MI whisker region projects bilaterally to the anteromedial (AM), ventromedial (VM), and ventrolateral (VL) nuclei, and to parts of the intralaminar nuclei. By contrast, the MI forepaw region sends virtually no projections to the contralateral thalamus. Consistent with these findings, bilateral injections of different tracers into the MI whisker region of each hemisphere produced tracer overlap on both sides of the thalamus. Furthermore, MI whisker projections to the contralateral thalamus terminate in close proximity to the thalamocortical neurons that project to the MI whisker region of that contralateral hemisphere. The terminal endings of the contralateral corticothalamic projections contain small synaptic varicosities and other features that resemble the modulator pathways described for other corticothalamic projection systems. In addition, tracer injections into AM, VM, and VL revealed dense clusters of labeled neurons in layer VI of the medial agranular (Agm) zone, which corresponds to the MI whisker region. These results suggest that projections from the MI whisker region to the contralateral thalamus may modulate the callosal interactions that are presumed to play a role in coordinating bilateral whisking behavior.

c Biocatalyst robustness toward stresses imposed during fermentation is important for efficient bio-based production. Osmotic stress, imposed by high osmolyte concentrations or dense populations, can significantly impact growth and productivity. In order to better understand the osmotic stress tolerance phenotype, we evolved sexual (capable of in situ DNA exchange) and asexual Escherichia coli strains under sodium chloride (NaCl) stress. All isolates had significantly improved growth under selection and could grow in up to 0.80 M (47 g/liter) NaCl, a concentration that completely inhibits the growth of the unevolved parental strains. Whole genome resequencing revealed frequent mutations in genes controlling N-acetylglucosamine catabolism (nagC, nagA), cell shape (mrdA, mreB), osmoprotectant uptake (proV), and motility (fimA). Possible epistatic interactions between nagC, nagA, fimA, and proV deletions were also detected when reconstructed as defined mutations. Biofilm formation under osmotic stress was found to be decreased in most mutant isolates, coupled with perturbations in indole secretion. Transcriptional analysis also revealed significant changes in ompACGL porin expression and increased transcription of sulfonate uptake systems in the evolved mutants. These findings expand our current knowledge of the osmotic stress phenotype and will be useful for the rational engineering of osmotic tolerance into industrial strains in the future. Escherichia coli, an important industrial microorganism for the production of a wide variety of fine chemicals, fuels, and proteins, has been extensively targeted to improve its suitability as a biofactory. Strain development efforts have focused on improving tolerance of feedstocks containing toxic compounds (1, 2) or products (3, 4). Many environmental variables, including osmotic pressure, can negatively impact biocatalyst performance (5). Use of nonconventional waste streams, such as waste glycerol or brackish water sources, to support microbial growth can also reduce process costs (6, 7) while reducing pressure on fresh water resources; however, these carbon and water sources generally contain high concentrations of salt that may be inhibitory to microbial growth. In addition to osmotic stresses, excess Na ϩ can disrupt the ion homeostasis in E. coli as well (8). Previous studies have attempted to engineer improved osmotic tolerance in E. coli (9, 10), but overall, knowledge of the genetic mechanisms that confer tolerance of osmotic stress in general or to specific osmolytes remains limited. A detailed analysis of E. coli osmotolerance to osmolytes would therefore provide new insight into the molecular mechanisms underlying this complex phenotype.Adaptive laboratory evolution (11) is a promising approach to identify potentially novel osmotic tolerance mechanisms, as this technique requires no assumptions about the underlying genotype-phenotype relationship. Complex phenotypes, such as enhanced resistance to biofuels (3,4,12), lignocellulosic hydrolysates (2, 13), antibiot...

An evolutionary engineering approach for enhancing heterologous carotenoids production in an engineered Saccharomyces cerevisiae strain was used previously to isolate several carotenoids hyper-producers from the evolved populations. β-Carotene production was characterized in the parental and one of the evolved carotenoids hyper-producers (SM14) using bench-top bioreactors to assess the impact of pH, aeration, and media composition on β-carotene production levels. The results show that with maintaining a low pH and increasing the carbon-to-nitrogen ratio (C:N) from 8.8 to 50 in standard YNB medium, a higher β-carotene production level at 25.52 ± 2.15 mg β-carotene g(-1) (dry cell weight) in the carotenoids hyper-producer was obtained. The increase in C:N ratio also significantly increased carotenoids production in the parental strain by 298 % [from 5.68 ± 1.24 to 22.58 ± 0.11 mg β-carotene g(-1) (dcw)]. In this study, it was shown that Raman spectroscopy is capable of monitoring β-carotene production in these cultures. Raman spectroscopy is adaptable to large-scale fermentations and can give results in near real-time. Furthermore, we found that Raman spectroscopy was also able to measure the relative lipid compositions and protein content of the parental and SM14 strains at two different C:N ratios in the bioreactor. The Raman analysis showed a higher total fatty acid content in the SM14 compared with the parental strain and that an increased C:N ratio resulted in significant increase in total fatty acid content of both strains. The data suggest a positive correlation between the yield of β-carotene per biomass and total fatty acid content of the cell.

is a member of the normal human microbiota and often resides on mucosal surfaces such as the oral cavity or the gastrointestinal tract. In addition to their commensality, species can opportunistically become pathogenic if the host microbiota is disrupted or if the host immune system becomes compromised. An important factor for pathogenesis is its ability to form biofilm communities. The two most medically important species- and -are often coisolated from infection sites, suggesting the importance of coculture biofilms. In this work, we report that biofilm formation of the coculture population depends on the relative ratio of starting cell concentrations of and When using a starting ratio of to of 1:3, ∼6.5- and ∼2.5-fold increases in biofilm biomass were observed relative to those of a monoculture and a/ ratio of 1:1, respectively. Confocal microscopy analysis revealed the heterogeneity and complex structures composed of long hyphae and cell clusters in the coculture biofilms, and reverse transcription-quantitative PCR (qRT-PCR) studies showed increases in the relative expression of the and adhesion genes in the / 1:3 biofilm compared to that in the monoculture biofilm. Additionally, only the 1:3/ biofilm demonstrated an increased resistance to the antifungal drug caspofungin. Overall, the results suggest that interspecific interactions between these two fungal pathogens increase biofilm formation and virulence-related gene expression in a coculture composition-dependent manner. and are often coisolated during infection, and the occurrence of coisolation increases with increasing inflammation, suggesting possible synergistic interactions between the two species in pathogenesis. During the course of an infection, the prevalence of each species may change over time due to differences in metabolism and in the resistance of each species to antifungal therapies. Therefore, it is necessary to understand the dynamics between and in coculture to develop better therapeutic strategies against infections. Existing work has focused on understanding how an equal-part culture of and impacts biofilm formation and pathogenesis. What is not understood, and what is investigated in this work, is how the composition of species in coculture impacts overall biofilm formation, virulence gene expression, and the therapeutic treatment of biofilms.

To make biorefineries sustainable, codesign of fractionation technologies and lignin valorization has been found to be essential. Combinatorial organosolv pretreatment (COP) was thus developed in an effort to efficiently produce sugars and improve lignin processability for the fabrication of lignin nanoparticles (LNPs). COP produced greater than a 90% glucose yield and 73% xylose yield, suggesting the improved sugar release from biomass. LNPs were fabricated from the lignin fractionated by COP via antisolvent precipitation. The smallest effective diameter (142 nm) of LNPs was obtained from COP using EtOH plus sulfuric acid. These LNPs possessed a lower polydispersity index and higher zeta potential, suggesting superior uniformity and greater stability. The lignin characterization results indicated that COP using EtOH plus sulfuric acid cleaved more β-O-4 and β–β linkages and produced lignin with a higher molecular weight and increased G-lignin and C5-substituted OH contents, suggesting the generation of condensed lignin. These modifications enhanced the hydrophobic interactions between lignins and thus enabled the fabrication of LNPs with a small particle size. COP using EtOH plus sulfuric acid also enriched total phenolic OH content and could promote the formation of a hydrogen-bonding network within LNPs. Together with a high zeta potential due to the increased phenolic OH and COOH groups, the stability of LNPs was thus enhanced. Overall, COP increased the sugar release from biomass and improved the lignin processability to facilitate the design of LNPs with satisfactory properties, which showed the potential to improve the lignin valorization and the sustainability of biorefineries.