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Abstract: Interactions between bacteria and bacteriophage viruses (phages) are known to influence pathogen growth and virulence, microbial diversity and even biogeochemical cycling. Lytic phages in particular infect and lyse their host cells, and can therefore have significant effects on cell densities as well as competitive dynamics within microbial communities. Despite the known impacts of lytic phages on the ecology and evolution of bacteria in free‐living communities, little is known about the role of lytic phages in host‐associated microbiomes. We set out to characterize the impact of phages in the tomato phyllosphere, that is the bacteria associated with above‐ground plant tissues, by transferring microbial communities from field‐grown tomato plants to juvenile plants grown under mostly sterile conditions in either the presence or absence of their associated phage community. In three separate experiments, we found that the presence of phages affects overall bacterial abundance during colonization of new host plants. Furthermore, bacterial community analysis using 16S rRNA amplicon sequencing shows that phages significantly alter the relative abundance of dominant community members and can influence both within‐ and among‐host diversity. These results underscore the importance of lytic phages in host‐associated microbiomes and are relevant to microbiome transplantation approaches, as they suggest transferring nonbacterial components of the microbiome among hosts is likely to have a strong impact on growth of both the resident and colonizing microbiota. [ABSTRACT FROM AUTHOR]

Purpose Traumatic brain injury ( TBI) is an important cause of morbidity and mortality in children, and early posttraumatic seizures ( EPTS) are a contributing factor to ongoing acute damage. Continuous video- EEG monitoring ( cEEG) was utilized to assess the burden of clinical and electrographic EPTS. Methods Eighty-seven consecutive, unselected (mild - severe), acute TBI patients requiring pediatric intensive care unit ( PICU) admission at two academic centers were monitored prospectively with cEEG per established clinical TBI protocols. Clinical and subclinical seizures and status epilepticus ( SE, clinical and subclinical) were assessed for their relation to clinical risk factors and short-term outcome measures. Key Findings Of all patients, 42.5% (37/87) had seizures. Younger age (p = 0.002) and injury mechanism (abusive head trauma - AHT, p < 0.001) were significant risk factors. Subclinical seizures occurred in 16.1% (14/87), while 6.9% (6/87) had only subclinical seizures. Risk factors for subclinical seizures included younger age (p < 0.001), AHT (p < 0.001), and intraaxial bleed (p < 0.001). SE occurred in 18.4% (16/87) with risk factors including younger age (p < 0.001), AHT (p < 0.001), and intraaxial bleed (p = 0.002). Subclinical SE was detected in 13.8% (12/87) with significant risk factors including younger age (p < 0.001), AHT (p = 0.001), and intraaxial bleed (p = 0.004). Subclinical seizures were associated with lower discharge King's Outcome Scale for Childhood Head Injury (KOSCHI) score (p = 0.002). SE and subclinical SE were associated with increased hospital length of stay (p = 0.017 and p = 0.041, respectively) and lower hospital discharge KOSCHI (p = 0.007 and p = 0.040, respectively). Significance cEEG monitoring significantly improves detection of seizures/SE and is the only way to detect subclinical seizures/ SE. cEEG may be indicated after pediatric TBI, particularly in younger children, AHT cases, and those with intraaxial blood on computerized tomography ( CT). [ABSTRACT FROM AUTHOR]

Interest is increasing in plastic compounding plants that offer tailor-made resins. Such plants produce a wide range of products in small quantities and with frequent changeovers. The underlying scheduling problem has been extensively researched; however, the concept of incorporating qualities of the finished product in the problem of plastics compounding has not been considered. We express product qualities as an additional problem constraint so that the production schedule ensures product quality. The additional constraint makes this mixed integer nonlinear program (MINLP) problem more difficult to solve. Several case studies are solved to illustrate the utility of the proposed approach. Experiments demonstrated that qualities of the finished product can be ensured a priori if the appropriate relations are developed and integrated in the optimisation model. As well, this paper provides insight into the economic aspects of the scheduling problem under consideration. Experiments showed that none of the cost components (operation, raw material, inventory, penalty or utilities) can alone play the role of the optimisation criterion. © 2012 Canadian Society for Chemical Engineering [ABSTRACT FROM AUTHOR]