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Biomass-based aerogels are of interest due to their abundant precursors, ease of functionalization, eco-friendliness, low cost, and effectiveness in dye-contaminated water treatment. Coconut pith (CP) known as a by-product after coconut processing is a sponge-like and lightweight material discarded in large volumes. For the first time, carbon micro-particles resulting from two-step treatment and pyrolysis of CP have been successfully incorporated with chitosan to produce aerogel composites by high-speed homogenization and freeze-drying. After pretreatment, holocellulose content and crystallinity index of the recovered CP pulp are respectively 75.4 and 58.6 % along with a solid recovery rate of 27.5 %. Characteristic properties of the aerogel composites are featured by their density as low as 15.23–28.17 mg/cm3, remarkably high porosity of 98.17–99.05 %, and Young's modulus of 1.64–12.23 kPa. Synergistic effects of the porous network, electrostatic interactions between both amine groups in chitosan and carbon surface with methyl orange (MO) cause the as-fabricated aerogel composites to achieve an extremely high adsorption capacity of 454.13 mg/g and removal efficiency of 92.32 % at initial MO concentration of 500 mg/L. Therefore, the CP-derived carbon/chitosan aerogel composites synthesized from a feasible procedure exhibit their great potential in enhancing the value of coconut waste and dealing with dye-contaminated water pollution by simple and economical adsorption. [ABSTRACT FROM AUTHOR]

Lignin derived from rice straw, an abundant renewable feedstock in nature, has the potential to be utilized as a substitute for fossil fuels in the production of value-added aromatic derivatives. However, depolymerization becomes one of the most difficult obstacles in the lignin-to-valuable products conversions due to the structural complexity and recalcitrance of lignin. In this work, rice straw-derived lignin was depolymerized to aromatics by using the hydrothermal liquefaction method in the ethanol-water solvent under hydrogen pressure. Effects of various process parameters on yields such as reaction time, ethanol concentration, reaction temperature, initial hydrogen pressure, and solvent-to-lignin ratio, were investigated. The suitable conditions for the highest yield of oil products (~ 75 %) were determined to be 65 vol. % ethanol, 250 °C, 60 min, 20 bar of hydrogen, and the solvent-to-lignin ratio of 35 mL/g. The obtained oil products were characterized by gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared (FT-IR). The bio-oil was mainly aromatics such as phenol, 3-ethylphenol, guaiacol and had a heating value of 22.2 MJ/kg. Hydrothermal liquefaction was demonstrated as an appropriate method for lignin depolymerization into aromatic compounds with high production yields.

PurposeThis review summarizes the conclusions and recommendations of the new National Council on Radiation Protection and Measurements (NCRP) Commentary No. 26 guidance on radiation dose limits for the lens of the eye. The NCRP addressed radiation protection principles in respect to the lens of the eye, discussed the current understanding of eye biology and lens effects, reviewed and evaluated epidemiology, and assessed exposed populations with the potential for significant radiation exposures to the lens while suggesting monitoring and protection practices.ConclusionsRadiation-induced damage to the lens of the eye can include the loss of clarity resulting in opacification or clouding several years after exposure. The impact is highly dependent on the type of radiation, how the exposure of the lens was delivered, the genetic susceptibilities of the individual exposed, and the location of the opacity relative to the visual axis of the individual. The preponderance of epidemiological evidence suggests that lens damage could occur at lower doses than previously considered and the NCRP has determined that it is prudent to reduce the recommended annual lens of the eye occupational dose limit from an equivalent dose of 150 mSv to an absorbed dose of 50 mGy. Significant additional research is still needed in the following areas: comprehensive evaluation of the overall effects of ionizing radiation on the eye, dosimetry methodology and dose-sparing optimization techniques, additional high quality epidemiology studies, and a basic understanding of the mechanisms of cataract development.

Previous National Council on Radiation Protection and Measurements (NCRP) publications have addressed the issues of risk and dose limitation in radiation protection and included guidance on specific organs and the lens of the eye. NCRP decided to prepare an updated commentary intended to enhance the previous recommendations provided in earlier reports. The NCRP Scientific Committee 1-23 (SC 1-23) is charged with preparing a commentary that will evaluate recent studies on the radiation dose response for the development of cataracts and also consider the type and severity of the cataracts as well as the dose rate; provide guidance on whether existing dose limits to the lens of the eye should be changed in the United States; and suggest research needs regarding radiation effects on and dose limits to the lens of the eye. A status of the ongoing work of SC 1-23 was presented at the Annual Meeting, "Changing Regulations and Radiation Guidance: What Does the Future Hold?" The following represents a synopsis of a few main points in the current draft commentary. It is likely that several changes will be forthcoming as SC 1-23 responds to subject matter expert review and develops a final document, expected by mid 2016.

Depolymerization of lignin is an important step to obtain a lignin monomer for the synthesis of functional chemicals. In the context of more lignin produced from biomass and pulp industry, converting real lignin with low purity is still required more studies. In this study, the influence of solvent composition and reaction parameters such as binary solvents ratio, time, and temperature, the solvent-to-lignin ratio on the depolymerization of rice straw lignin was investigated carefully. Essential lignin-degraded products including liquid product (LP), char (solid), and gas were obtained, and their yields were directly influenced by reaction conditions. Results show that the maximum lignin conversion rate of 92% and LP yield of 66% was under the condition of 275°C, 30 min, 75 : 1 (mL solvent/1 g lignin), and ethanol 50%. Gas chromatography-mass spectroscopy (GC-MS) analysis was used for the analysis of the depolymerization products and identified 11 compounds which are mainly phenolic compounds such as 2-ethylphenol, 3-ethylphenol, phenol, methyl 2,4,6-trimethylbenzoate. The structure changes of LP and char in various conditions were analyzed using Fourier-transform infrared (FTIR).

Each year, the global annual production of coconut fibre (CF) is around 350×103 t, while they are utilized for fine art, fertilization, and animal feed. However, there have not seen many engineering applications to utilize these materials. The coir with high cellulose content of over 40 % has potential for high-value engineering applications like fabricating cellulose-based aerogels. Recently, the cellulose aerogel from CF was formed using a sol-gel method in an NaOH/Urea solution, with an anticipated completion time of 7 d due to the time required for gelation and solvent exchange, which might take up to 4 d. This demonstrates that the present approach is subject to several time limitations. To improve this, for the first time, a novel fabrication of aerogels from the CF with chemical pre-treatment in advance has been successfully developed by using polyvinyl alcohol (PVA) and xanthan gum (XTG) as biodegradable binders. The treated CFs are dispersed homogeneously into a PVA/XTG solution, followed by freeze-drying to remove water, leaving behind a highly porous called CF aerogel. The influences of CF content on CF aerogels' physical and mechanical characteristics, as well as oil adsorption and thermal conductivity, have all been thoroughly investigated. For oil removal, the fabricated CF aerogels are surface-modified with methyltrimethoxysilane (MTMS) to enhance their hydrophobicity. This method required 2 times less time and used fewer chemicals while retaining the same oil adsorption capabilities of up to 20 g/g as previous CF aerogel and demonstrating additional good insulation of 0.040 W/(m·K). Thus, this study provides a new novel approach to synthesize an oil-absorbing and insulating CF aerogel.

ObjectivesTo examine development in illness perceptions of type 1 diabetes across adolescence and relationships with intelligence, diabetes responsibility, and diabetes outcomes.MethodsIllness perceptions were measured via the Illness Perceptions Questionnaire at 3 times, every 6 months in 213 adolescents (M age = 13.00; SD = 1.54) with type 1 diabetes. Intelligence and adolescents' perceived responsibility for diabetes were examined, and adolescents' report of adherence and quality of life (QOL), and glycosylated hemoglobin (HbA1c) from medical records addressed diabetes-related outcomes.ResultsLinear growth models showed significant increases in perceptions of diabetes coherence, chronicity, consequences, personal and treatment control, and decreases in diabetes cyclicality and parental control across time. More favorable illness perceptions were generally associated with adolescent intelligence at baseline, more adolescent responsibility for management, better adherence and QOL, and lower HbA1c at each time point.ConclusionsResults suggest that adolescents develop complex illness perceptions, which are associated with better diabetes management.

Two previously unreported dimethylpyranoflavanones, pyronomelodorones A and B (1 and 2), along with five known compounds, 7-O-methyldihydrowogonin (3), 5,6,7-trimethoxyflavanone (4), 5,6-dihydroxy-7-methoxy-dihydroflavone (5), 5,7,8-trimethoxydihydroflavone (6), and pinostrobin (7), were isolated from the roots of Melodorum fruticosum. The structures of all isolates were fully characterized using spectroscopic data and comparison with the previous literature. All isolates were evaluated for their in vitro α-glucosidase inhibition and their cytotoxicity against KB, HepG2, and MCF7 cell lines. Among the isolates, compound 1 exhibited the most inhibitory activity against α-glucosidase and was superior to the positive control with an IC50 value of 1.32 μM. Compounds 1 and 2 showed weak cytotoxicity against the three human cancer cell lines, with IC50 values in the range of 53.3–79.0 μM. [ABSTRACT FROM AUTHOR]

Objectives: Anxiety and anticipatory stressors are commonly experienced by children visiting the Pediatric Emergency Department (PED), but little research exists that addresses the efficacy of interventions to decrease this stress. This one-sample pretest-postest pilot study gathered preliminary data on the feasibility and effectiveness of utilizing audiobooks to reduce fear and state anxiety in children in the PED.Methods: Participants were 131 children in kindergarten through 8th grade (M = 9.4 years, 54% female), triaged urgent or emergent, presenting to the PED. Participants self-reported fear (Children's Fear Scale) and state anxiety (modified State-Trait Anxiety Inventory for Children; mSTAIC) before and after listening to an age-appropriate audiobook (two options). Data regarding patient experience were also collected. Paired samples t-test was used to examine pre–post intervention changes in fear and state anxiety.Results: Significant, albeit small, improvements in fear and the mSTAIC states of nervous, calm, happy, and relaxed were found after use of the audiobook (Cohen's dz = 0.22–0.35). Small, yet significant correlations were found between child age/grade level and improvements in fear and in the mSTAIC states of scared and relaxed, suggesting that the audiobook was more beneficial for older participants. Over 60% of participants liked the audiobook content “a lot” as well as enjoyed listening to the audiobook “a lot.” Without prompting, 15% of participants requested to listen to an additional audiobook.Conclusions: Listening to an audiobook is feasible and could be effective in decreasing fear and state anxiety for children during a waiting period in the PED. The technology is low-cost, simple, and portable. The results of this study should be interpreted with prudence due to the lack of a control group and results that, although significant, were modest based on effect size conventions; future studies should explore the impact of audiobooks on patient stress with an expanded sample size and control group.

Multimedia in assessing clinical decision-making skills (CDMS) has been poorly studied, particularly in comparison to traditional text-based assessments. The literature suggests multimedia is more difficult for trainees. We hypothesize that pediatric residents score lower in diagnostic skill when clinical vignettes use multimedia rather than text for patient findings. A standardized method was developed to write text-based questions from 60 high-resolution, quality multimedia; a series of expert panels selected 40 questions with both a multimedia and text-based counterpart, and two online tests were developed. Each test featured 40 identical questions with reciprocal and alternating modality (multimedia vs. text). Pediatric residents and rising 4th year medical students (MS-IV) at a single residency were randomized to complete either test stratified by postgraduate training year (PGY). A mixed between-within subjects ANOVA analyzed differences in score due to modality and PGY. Secondary analyses ascertained modality effect in dermatology and respiratory questions using Mann-Whitney U tests, and correlations on test performance to In-service Training Exam (ITE) scores using Spearman rank. Eighty-eight residents and rising interns completed the study. Overall multimedia scores were lower than text-based scores (p = 0.047, ?[subscript p, superscript 2] = 0.04), with highest disparity in rising interns (MS-IV); however, PGY had a greater effect on scores (p = 0.001, ?[subscript p, superscript 2] = 0.16). Respiratory questions were not significantly lower with multimedia (n = 9, median 0.71 vs. 0.86, p = 0.09) nor dermatology questions (n = 13, p = 0.41). ITEs correlated significantly with text-based scores (? = 0.23-0.25, p = 0.04-0.06) but not with multimedia scores. In physician trainees with less clinical experience, multimedia-based case vignettes are associated with significantly lower scores. These results help shed light on the role of multimedia versus text-based information in CDMS, particularly in less experienced clinicians.