Dust Explosion Characteristics of Cellulose Acetates with Different Degrees of Acetylation

PresentationIn this work, the relation between various degrees of acetylation (CAs) of Cellulose acetate (CA) to dust explosion characteristics as minimum explosible concentration (MEC) and minimum ignition energy (MIE) have been studied. Also, we attempt to clarify the relative of moisture content and water adsorption to cellulose, cellulose ester as CA and cellulose ether as Methyl cellulose (MC), Ethyl cellulose (EC), Hydroxyethyl cellulose (HEC), Hydroxypropyl cellulose (HPC), and sodium carboxymethyl cellulose (CMC) to MEC and MIE have been studied. We found that the chemical derivatives have significant on thermal behavior of cellulose which Td of CA shifted to higher temperature because of acetate derivative effect. Meanwhile, Td of cellulose ethers as MC, EC, HEC, HEC and CMC were shifted to lower temperature. Moreover, CAs was not evident effect to Td of CA. Moisture content of cellulose powder had not significant on MEC of both air dry and absolute dry powder were 55 g/m3. But, we found MEC was relative to its moisture content of CA which absolute dry was more sensitive on explosion than dry CA powder. However, MEC was consistent with the hydrophilicity index at 75%RH of dry and absolute dry of cellulose, cellulose acetate and cellulose ethers in present work. MIE was not corresponding to moisture content of cellulose ether and cellulose ester but it was relative to cellulose. The results from our experiments, comparing with CAs, chemical derivatives have more significant on moisture adsorption, thermal stability and dust explosion characteristics of cellulose

Phylogenetic Revision of Savoryellaceae and Evidence for Its Ranking as a Subclass

Morphology, phylogeny, and molecular clock analyses were carried out on Savoryellaceae in order to understand the placements of taxa in this family. Ascotaiwania and Neoascotaiwania formed a well-supported separate clade in the phylogeny of concatenated partial SSU, LSU, TEF, and RPB2 gene data. These two genera share similar morphological features, especially in their asexual morphs, indicating that they are congeneric. Hence, we synonymize Neoascotaiwania under Ascotaiwania. Ascotaiwania hughesii (and its asexual morph, Helicoon farinosum) and Monotosporella setosa grouped in a clade sister to Pleurotheciales and are excluded from Ascotaiwania which becomes monophyletic. A novel genus Helicoascotaiwania is introduced to accommodate Ascotaiwania hughesii and its asexual morph, Helicoon farinosum. A novel species, Savoryella yunnanensis is introduced from a freshwater habitat in Yunnan Province, China. Comprehensive descriptions and illustrations are provided for selected taxa in this family. In addition, we provide evolutionary divergence estimates for Savoryellomycetidae taxa and major marine based taxa to support our phylogenetic and morphological investigations. The taxonomic placement of these marine-based taxa is briefly discussed. Our results indicate that the most basal group of marine-based taxa are represented within Lulworthiales, which diverged from ancestral Sordariomycetes around 149 Mya (91–209) and Savoryellomycetidae around 213 Mya (198–303)

Brief Report: Lopinavir Hair Concentrations Are the Strongest Predictor of Viremia in HIV-Infected Asian Children and Adolescents on Second-Line Antiretroviral Therapy.

BackgroundChildren/adolescents display suboptimal antiretroviral therapy (ART) adherence and outcomes versus adults. Hair ART concentrations are objective adherence measures that predict viremia in adults but longitudinal data on hair levels in pediatric populations is limited. We assessed the predictive utility of hair lopinavir (LPV) levels on viremia among youth on second-line ART.MethodsWe examined predictors of viremia (HIV-1 RNA >400 and >1000 copies/mL) at least 24 weeks after switch to LPV-based second-line ART in a cohort of HIV-infected Asian children followed between 2011 and 2014. Small hair samples, HIV-1 RNA, and self-reported adherence were collected biannually. Hair concentrations of LPV were measured through liquid chromatography/tandem mass spectrometry using validated methods. Time-to-first viremia was examined using discrete-time Cox models.ResultsOverall, 244 children met the inclusion criteria for the present analysis. Approximately half (55%) were boys and the median age 10 years [interquartile range (IQR) 7-13]; 40% were older than 11 years. At switch to second-line ART, median CD4 count was 300 (IQR 146-547) cells/mm and median HIV-RNA level was 5.0 (IQR 4.3-5.6) log10/mL. Median time of study follow-up was 48 weeks and a median of 3 (range 1-5) hair samples were collected from each participant. Adjusting for age, sex, country, self-reported adherence, CD4, and HIV-RNA, higher LPV hair concentrations were the strongest predictor of lower odds of viremia (HIV-RNA >400 copies/mL adjusted odds ratio = 0.41 per doubling in hair concentration, 95% confidence interval: 0.29 to 0.58, P < 0.001; HIV-RNA >1000 copies/mL, adjusted odds ratio = 0.54, 95% confidence interval: 0.45 to 0.65, P < 0.001).ConclusionsHair concentrations predict viremia among children with HIV on second-line ART and could guide clinical decisions for this population