Ring-opening terpolymerisation of phthalic thioanhydride with carbon dioxide and epoxides

In seeking to expand the portfolio of accessible polymer structures from CO2 waste, we report the ring-opening terpolymerisation (ROTERP) of phthalic thioanhydride with CO2 and epoxides, forming statistical poly(ester-thioester-carbonates) by employing heterobimetallic catalysts. Both metal choice and ligand chemistry modulate the amount of CO2 incorporated into the polymer microstructure. Terpolymerisation occurs when maintaining polymerisation rates of the faster parent ring-opening copolymerisation and this finding led us to develop the formation of CO2-derived terpolymers with butylene oxide at low CO2 pressure under bicomponent catalysis. Tetrapolymerisation with added phthalic anhydride leads to the preferential polymerisation of phthalic anhydride before the polymerisation of sulfur derivatives with CO2 and epoxides. Finally, we show that the presence of sulfur-containing thioester links leads to polymers with degradability benefits compared to those from all-oxygen derivatives

Oral hygiene knowledge versus behavior in children: A questionnaire-based, interview-style analysis and on-site assessment of toothbrushing practices

Objectives: Oral hygiene plays an important role in eliminating biofilms and preventing dental caries. However, the implementation of oral health knowledge that children learn from their parents and through school dental health programmes remains poorly studied. This study aimed to investigate oral hygiene knowledge and its practical utilization in children and young adolescents (CYAs) aged 2–15 years. Material and methods: This was a questionnaire‐based, interview‐style community survey and on‐site practical assessment of CYAs' toothbrushing skills conducted during two 1‐day public science‐promoting events held at a major German university hospital in consecutive years. CYAs first answered questions on toothbrushing frequency, dental aids used, and dental care. They subsequently underwent diagnostic staining and demonstrated their brushing technique and method. CYAs' responses (percentages) to questionnaire items addressing oral hygiene knowledge and practice, and on‐site assessment of toothbrushing skills served as the main outcome measures. Results: Of 244 participating CYAs, 178 (73%) CYAs had no caries experience, the percentage increasing with age from 5% in 2–5‐year‐olds to 40% in those aged > 10 years. Of 117/244 (48%) indicating that teeth should be brushed three times daily, 80/ 117 (68%) self‐reported twice‐daily brushing, 32/117 (27%) reported brushing three times, and 4/117 (3%) stated doing so only once. Although 131/244 (54%) considered that teeth should be brushed for 3 min, 77/131 (59%) self‐reported actually doing so and 41/131 (31%) reported brushing for 2min. Seventeen of 42 (40%) participants aged > 10 years showed no systematic brushing method, with 21/42 (50%) failing to clean their teeth completely. Participants aged 6–10 years exhibited the highest proportion (97/134, 72%) of complete cleaning. One hundred and forty‐six of 244 (60%) of CYAs knew about floss; 63/134 (43%) reported using it. Good adherence to oral health recommendations (i.e., brushing ≥ 2/day for ≥2min) was observed in 212/ 244 (87%) CYAs, the remaining 32/244 (13%) exhibiting poor adherence. Conclusion: CYAs knew about the importance of oral hygiene and cleaned their teeth frequently. However, translation of their knowledge into practice showed deficiencies. Repeated encouragement to put oral health knowledge into practice is important

Mechanistic mapping of (CS2/CO2)/epoxide copolymerization catalysis leads to terpolymers with improved degradability

The placement of main-group functionalities within polymers represents a strategy to access a wide catalog of materials but is limited by poor understanding of the catalyst selection criteria and polymerization mechanism when moving down the periodic table. Here, we study a series of new heterobimetallic carbon dioxide and carbon disulfide/epoxide copolymerization catalysts that allow for a comparative mechanistic understanding of two ring-opening copolymerization processes. We reveal that the distinct roles each metal plays are preserved from carbon dioxide to carbon disulfide, maintaining activity and selectivity across copolymerizations. Experimental and computational studies show that carbon disulfide/epoxide copolymerization can be understood as a series of structurally related insertion events that are interlinked by a central oxygen/sulfur scrambling reaction at the propagating chain end. This facilitates the synthesis of new carbon dioxide-/carbon disulfide-/epoxide-derived terpolymers with improved degradability over the parent carbon dioxide/epoxide copolymers at low levels of sulfur incorporation

Cognitive Information Processing

Contains reports on three research projects.National Science Foundation (Grant GP-2495)National Institutes of Health (Grant MH-04737-04)National Aeronautics and Space Administration (Grant NsG-496

Bacterial 16S rRNA/rDNA Profiling in the Liquid Phase of Human Saliva

Human saliva can be separated by centrifugation into cell pellet and cell-free supernatant, which are called cellular phase and liquid phase in this study. While it is well documented that the cellular phase of saliva contains hundreds of oral bacteria species, little is known whether the liquid phase of saliva contains any information related to oral microbiota. In this study, we analyzed the bacterial nucleic acid contents of the liquid phase of saliva. Using primers universal to most eubacterial 16S rDNA, we detected large amounts of bacterial 16S rRNA and rDNA in the cell-free phase of saliva. Random sequencing analysis of forty PCR amplicons from the cell-free phase of saliva led to 15 operational taxonomic unit (OTU) groups. Furthermore, using denaturing gradient gel electrophoresis (DGGE), we compared 16S rRNA/rDNA profiles derived from liquid phases and cellular phases of saliva samples, and found positive correlations (Pearson Correlation=0.822, P<0.001) between these sample groups. These findings indicate that the liquid phase of saliva contains numerous bacterial 16S rRNA/rDNA molecules that have correlations with bacteria existing in the cellular phase

Outcome Prediction in Pneumonia Induced ALI/ARDS by Clinical Features and Peptide Patterns of BALF Determined by Mass Spectrometry

BACKGROUND: Peptide patterns of bronchoalveolar lavage fluid (BALF) were assumed to reflect the complex pathology of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) better than clinical and inflammatory parameters and may be superior for outcome prediction. METHODOLOGY/PRINCIPAL FINDINGS: A training group of patients suffering from ALI/ARDS was compiled from equal numbers of survivors and nonsurvivors. Clinical history, ventilation parameters, Murray's lung injury severity score (Murray's LISS) and interleukins in BALF were gathered. In addition, samples of bronchoalveolar lavage fluid were analyzed by means of hydrophobic chromatography and MALDI-ToF mass spectrometry (MALDI-ToF MS). Receiver operating characteristic (ROC) analysis for each clinical and cytokine parameter revealed interleukin-6>interleukin-8>diabetes mellitus>Murray's LISS as the best outcome predictors. Outcome predicted on the basis of BALF levels of interleukin-6 resulted in 79.4% accuracy, 82.7% sensitivity and 76.1% specificity (area under the ROC curve, AUC, 0.853). Both clinical parameters and cytokines as well as peptide patterns determined by MALDI-ToF MS were analyzed by classification and regression tree (CART) analysis and support vector machine (SVM) algorithms. CART analysis including Murray's LISS, interleukin-6 and interleukin-8 in combination was correct in 78.0%. MALDI-ToF MS of BALF peptides did not reveal a single identifiable biomarker for ARDS. However, classification of patients was successfully achieved based on the entire peptide pattern analyzed using SVM. This method resulted in 90% accuracy, 93.3% sensitivity and 86.7% specificity following a 10-fold cross validation (AUC = 0.953). Subsequent validation of the optimized SVM algorithm with a test group of patients with unknown prognosis yielded 87.5% accuracy, 83.3% sensitivity and 90.0% specificity. CONCLUSIONS/SIGNIFICANCE: MALDI-ToF MS peptide patterns of BALF, evaluated by appropriate mathematical methods can be of value in predicting outcome in pneumonia induced ALI/ARDS

Patterns of paediatric end-of-life care: a chart review across different care settings in Switzerland.

Paediatric end-of-life care is challenging and requires a high level of professional expertise. It is important that healthcare teams have a thorough understanding of paediatric subspecialties and related knowledge of disease-specific aspects of paediatric end-of-life care. The aim of this study was to comprehensively describe, explore and compare current practices in paediatric end-of-life care in four distinct diagnostic groups across healthcare settings including all relevant levels of healthcare providers in Switzerland. In this nationwide retrospective chart review study, data from paediatric patients who died in the years 2011 or 2012 due to a cardiac, neurological or oncological condition, or during the neonatal period were collected in 13 hospitals, two long-term institutions and 10 community-based healthcare service providers throughout Switzerland. Ninety-three (62%) of the 149 reviewed patients died in intensive care units, 78 (84%) of them following withdrawal of life-sustaining treatment. Reliance on invasive medical interventions was prevalent, and the use of medication was high, with a median count of 12 different drugs during the last week of life. Patients experienced an average number of 6.42 symptoms. The prevalence of various types of symptoms differed significantly among the four diagnostic groups. Overall, our study patients stayed in the hospital for a median of six days during their last four weeks of life. Seventy-two patients (48%) stayed at home for at least one day and only half of those received community-based healthcare. The study provides a wide-ranging overview of current end-of-life care practices in a real-life setting of different healthcare providers. The inclusion of patients with all major diagnoses leading to disease- and prematurity-related childhood deaths, as well as comparisons across the diagnostic groups, provides additional insight and understanding for healthcare professionals. The provision of specialised palliative and end-of-life care services in Switzerland, including the capacity of community healthcare services, need to be expanded to meet the specific needs of seriously ill children and their families

Design und Qualitätskontrolle der zahnmedizinischen Untersuchung in der NAKO Gesundheitsstudie [Design and quality control of the oral health status examination in the German National Cohort (GNC)]

BACKGROUND: Caries and periodontitis are highly prevalent worldwide. Because detailed data on these oral diseases were collected within the framework of the German National Cohort (GNC), associations between oral and systemic diseases and conditions can be investigated. OBJECTIVES: The study protocol for the oral examination was designed to ensure a comprehensive collection of dental findings by trained non-dental staff within a limited examination time. At the mid-term of the GNC baseline examination, a first quality evaluation was performed to check the plausibility of results and to propose measures to improve the data quality. MATERIALS AND METHODS: A dental interview, saliva sampling and oral diagnostics were conducted. As part of the level‑1 examination, the number of teeth and prostheses were recorded. As part of the level‑2 examination, detailed periodontal, cariological and functional aspects were examined. All examinations were conducted by trained non-dental personnel. Parameters were checked for plausibility and variable distributions were descriptively analysed. RESULTS: Analyses included data of 57,967 interview participants, 56,913 level‑1 participants and 6295 level‑2 participants. Percentages of missing values for individual clinical parameters assessed in level 1 and level 2 ranged between 0.02 and 3.9%. Results showed a plausible distribution of the data; rarely, implausible values were observed, e.g. for measurements of horizontal and vertical overbite (overjet and overbite). Intra-class correlation coefficients indicated differences in individual parameters between regional clusters, study centres and across different examiners. CONCLUSIONS: he results confirm the feasibility of the study protocol by non-dental personnel and its successful integration into the GNC's overall assessment program. However, rigorous dental support of the study centres is required for quality management

Investigation of Bis(Perfluoro-tert-Butoxy) Halogenates(I/III)

A systematic study of halogenate(I/III) anions with polyatomic ligands is presented. The bis(perfluoro-tert-butoxy) halogenates(I) [X(OC4F9)2]−, X=Cl, Br, I, of chlorine, bromine, and iodine are prepared as their tetraethylammonium salts and characterized with IR, Raman, and NMR spectroscopic methods, as well as single-crystal X-ray diffraction analyses. Spectroscopical data are supported by quantum-chemical calculations. Additionally, the bonding situation of the species in question are analyzed and discussed. Furthermore, the oxidation to the corresponding halogenate(III) derivatives was studied. For [Br(OC4F9)2]−, oxidation with elemental fluorine gave [BrF2(OC4F9)2]−. Iodide was directly oxidized by ClOC4F9 to the IIII species [I(OC4F9)4]−, which is a surprisingly inert anion that might be used as a weakly coordinating anion (WCA) in the future. For [Cl(OC4F9)2]−, the decomposition products of the synthetic approaches towards a chlorine(III) system were analyzed