9 research outputs found

    Solvent and recovery process for lignin

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    Methods for obtaining purified lignin and the lignin that can be obtained by the methods are described. Methods include processing pretreated lignocellulosic biomass feedstock to recover the lignin and provide a lignin composition with a very low level of impurities such as metals and ash. In addition, the lignin recovered from the process can have a narrow molecular weight distribution and, depending upon the specific stages utilized in the process, can have a predetermined molecular weight. The process includes one or more separation stages in which a lignin-containing feedstock is mixed with a solvent solution. The mixture fractionates to form a solvent-rich liquid phase and a lignin-rich liquid phase, the lignin being partitioned across the phases according to the molecular weight of the lignin. Furthermore, the metal salts of the pretreated lignocellulosic biomass feedstock also partition across the phases

    Inventory of current EU paediatric vision and hearing screening programmes

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    Background: We examined the diversity in paediatric vision and hearing screening programmes in Europe. Methods: Themes relevant for comparison of screening programmes were derived from literature and used to compile three questionnaires on vision, hearing and public-health screening. Tests used, professions involved, age and frequency of testing seem to influence sensitivity, specificity and costs most. Questionnaires were sent to ophthalmologists, orthoptists, otolaryngologists and audiologists involved in paediatric screening in all EU fullmember, candidate and associate states. Answers were cross-checked. Results: Thirty-nine countries participated; 35 have a vision screening programme, 33 a nation-wide neonatal hearing screening programme. Visual acuity (VA) is measured in 35 countries, in 71% more than once. First measurement of VA varies from three to seven years of age, but is usually before the age of five. At age three and four picture charts, including Lea Hyvarinen are used most, in children over four Tumbling-E and Snellen. As first hearing screening test otoacoustic emission (OAE) is used most in healthy neonates, and auditory brainstem response (ABR) in premature newborns. The majority of hearing testing programmes are staged; children are referred after one to four abnormal tests. Vision screening is performed mostly by paediatricians, ophthalmologists or nurses. Funding is mostly by health insurance or state. Coverage was reported as >95% in half of countries, but reporting was often not first-hand. Conclusion: Largest differences were found in VA charts used (12), professions involved in vision screening (10), number of hearing screening tests before referral (1-4) and funding sources (8)

    Benign Fractionation of Lignin with CO<sub>2</sub>‑Expanded Solvents of Acetic Acid + Water

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    Kraft lignin was fractionated by molecular weight (MW), using CO<sub>2</sub>-expanded solutions of acetic acid/water in a 90/10 wt/wt ratio. In particular, as CO<sub>2</sub> pressures were increased from 7 bar to 48 bar, expanding the liquid-solvent phase and reducing its dielectric strength, lignin fractions decreasing in MW from 15 000 to 1250, with polydispersity index (PDI) values decreasing from 3.7 to 1.6, were obtained. The recovered lignin fractions were similar, in terms of chemical functionality. With the use of gas-expanded liquids (GXL), only one solvent composition is required, and recovery and reuse of the biorenewable CO<sub>2</sub> + acetic acid–water solution is facilitated through pressure release and recompression. The process was demonstrated for the recovery of seven lignin fractions to demonstrate its versatility and effectiveness, but simpler operation with recovery of just a low MW lignin fraction and a high MW lignin fraction is more consistent with anticipated applications

    Racial/Ethnic Disparities in Perioperative Outcomes of Major Procedures: Results From the National Surgical Quality Improvement Program.

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    OBJECTIVE: To determine the association between race/ethnicity and perioperative outcomes in individuals undergoing major oncologic and nononcologic surgical procedures in the United States. BACKGROUND: Prior work has shown that there are significant racial/ethnic disparities in perioperative outcomes after several types of major cardiac, general, vascular, orthopedic, and cancer surgical procedures. However, recent evidence suggests attenuation of these racial/ethnic differences, particularly at academic institutions. METHODS: We utilized the American College of Surgeons National Surgical Quality Improvement Program database to identify 142,344 patients undergoing one of the 16 major cancer and noncancer surgical procedures between 2005 and 2011. RESULTS: Eighty-five percent of the cohort was white, with black and Hispanic individuals comprising 8% and 4%, respectively. In multivariable analyses, black patients had greater odds of experiencing prolonged length of stay after 10 of the 16 procedures studied (all P \u3c 0.05), though there was no disparity in odds of 30-day mortality after any surgery. Hispanics were more likely to experience prolonged length of stay after 5 surgical procedures (all P \u3c 0.04), and were at greater odds of dying within 30 days after colectomy, heart valve repair/replacement, or abdominal aortic aneurysm repair (all P \u3c 0.03). Fewer disparities were observed for Hispanics, than for black patients, and also for cancer, than for noncancer surgical procedures. CONCLUSIONS: Important racial/ethnic disparities in perioperative outcomes were observed among patients undergoing major cancer and noncancer surgical procedures at American College of Surgeons National Surgical Quality Improvement Program institutions. There were fewer disparities among individuals undergoing cancer surgery, though black patients, in particular, were more likely to experience prolonged length of stay

    Radiation and Optics in the Atmosphere

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    \u3ci\u3eDrosophila\u3c/i\u3e Muller F Elements Maintain a Distinct Set of Genomic Properties Over 40 Million Years of Evolution

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    The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25–50%) than euchromatic reference regions (3–11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11–27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4–3.6 vs. 8.4–8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu

    Physiology and Pathophysiology of Cerebral Microcirculation

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