Effect of Pyrolysis Temperature on PhysicoChemical Properties and Acoustic-Based Amination of Biochar for Efficient CO\u3csub\u3e2\u3c/sub\u3e Adsorption

© Copyright © 2020 Chatterjee, Sajjadi, Chen, Mattern, Hammer, Raman and Dorris. The present study examined the effect of pyrolysis temperature on the physicochemical properties of biochar, activation process and carbon capture. Two different categories of biochars were synthesized from herbaceous (miscanthus and switchgrass) and agro-industrial (corn stover and sugarcane bagasse) feedstock under four different pyrolysis temperatures −500, 600, 700, and 800°C. The synthesized biochars underwent sono-amination activation comprising low-frequency acoustic treatment followed by amine functionalization to prepare adsorbents for CO2 capture. The highest increment (200%) of CO2 capture capacity was observed for sono-aminated samples prepared at 600 and 700°C (maximum improvement for miscanthus), while biochars synthesized at 500 and 800°C demonstrated comparatively lesser increment in adsorption capacities that falls in the range of 115–151 and 127–159%, respectively compared to 600 and 700°C. The elevated pyrolysis temperature (particularly 600 and 700°C) resulted in increased %C and %ash contents and reduced %N contents with enhancement of micro surface area and pore volume. Thus, the superior adsorption capacity of miscanthus (at 600 and 700°C) can be attributed to their large surface areas (303–325 m2/g), high carbon contents (82–84%), and low ash contents (4–5%), as well as %N contents after sono-amination that was twice that of raw char

SWIR Emissive RosIndolizine Dyes With Nanoencapsulation In Water Soluble Dendrimers

Shortwave infrared (SWIR) emission has great potential for deep-tissue in vivo biological imaging with high resolution. In this article, the synthesis and characterization of two new xanthene-based RosIndolizine dyes coded PhRosIndz and tolRosIndz is presented. The dyes are characterized via femtosecond transient absorption spectroscopy as well as steady-state absorption and emission spectroscopies. The emission of these dyes is shown in the SWIR region with peak emission at 1097 nm. TolRosIndz was encapsulated with an amphiphilic linear dendritic block co-polymer (LDBC) coded 10-PhPCL-G3 with high uptake yield. Further, cellular toxicity was examined in vitro using HEK (human embryonic kidney) cells where a \u3e90% cell viability was observed at practical concentrations of the encapsulated dye which indicates low toxicity and reasonable biocompatibility

Pharmacological and non-pharmacological interventions for non-respiratory sleep disturbance in children with neurodisabilities : a systematic review

BACKGROUND: There is uncertainty about the most appropriate ways to manage non-respiratory sleep disturbances in children with neurodisabilities (NDs). OBJECTIVE: To assess the clinical effectiveness and safety of NHS-relevant pharmacological and non-pharmacological interventions to manage sleep disturbance in children and young people with NDs, who have non-respiratory sleep disturbance. DATA SOURCES: Sixteen databases, including The Cochrane Central Register of Controlled Trials, EMBASE and MEDLINE, were searched up to February 2017, and grey literature searches and hand-searches were conducted. REVIEW METHODS: For pharmacological interventions, only randomised controlled trials (RCTs) were included. For non-pharmacological interventions, RCTs, non-randomised controlled studies and before-and-after studies were included. Data were extracted and quality assessed by two researchers. Meta-analysis and narrative synthesis were undertaken. Data on parents' and children's experiences of receiving a sleep disturbance intervention were collated into themes and reported narratively. RESULTS: Thirty-nine studies were included. Sample sizes ranged from 5 to 244 participants. Thirteen RCTs evaluated oral melatonin. Twenty-six studies (12 RCTs and 14 before-and-after studies) evaluated non-pharmacological interventions, including comprehensive parent-directed tailored (n = 9) and non-tailored (n = 8) interventions, non-comprehensive parent-directed interventions (n = 2) and other non-pharmacological interventions (n = 7). All but one study were reported as having a high or unclear risk of bias, and studies were generally poorly reported. There was a statistically significant increase in diary-reported total sleep time (TST), which was the most commonly reported outcome for melatonin compared with placebo [pooled mean difference 29.6 minutes, 95% confidence interval (CI) 6.9 to 52.4 minutes; p = 0.01]; however, statistical heterogeneity was extremely high (97%). For the single melatonin study that was rated as having a low risk of bias, the mean increase in TST was 13.2 minutes and the lower CI included the possibility of reduced sleep time (95% CI -13.3 to 39.7 minutes). There was mixed evidence about the clinical effectiveness of the non-pharmacological interventions. Sixteen studies included interventions that investigated the feasibility, acceptability and/or parent or clinician views of sleep disturbance interventions. The majority of these studies reported the 'family experience' of non-pharmacological interventions. LIMITATIONS: Planned subgroup analysis was possible in only a small number of melatonin trials. CONCLUSIONS: There is some evidence of benefit for melatonin compared with placebo, but the degree of benefit is uncertain. There are various types of non-pharmacological interventions for managing sleep disturbance; however, clinical and methodological heterogeneity, few RCTs, a lack of standardised outcome measures and risk of bias means that it is not possible to draw conclusions with regard to their effectiveness. Future work should include the development of a core outcome, further evaluation of the clinical effectiveness and cost-effectiveness of pharmacological and non-pharmacological interventions and research exploring the prevention of, and methods for identifying, sleep disturbance. Research mapping current practices and exploring families' understanding of sleep disturbance and their experiences of obtaining help may facilitate service provision development. STUDY REGISTRATION: This study is registered as PROSPERO CRD42016034067. FUNDING: The National Institute for Health Research Health Technology Assessment programme

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

SPECTROSCOPIC INVESTIGATIONS OF NEWLY DEVELOPED MATERIALS FOR LIGHT HARVESTING, ENERGY CONVERSION, AND BIOIMAGING

A multitude of spectroscopic techniques were employed in the making of this dissertation to investigate materials with environmental, commercial, optoelectronic, bioimaging, and solar energy conversion applications. Graphene-like materials like biochar represent a field of study in which bioavailable materials are deployed for CO2 and heavy-metal adsorption to combat the detrimental effects of industry on the environment. Vibrational characterization of these materials via Raman spectroscopy is integral in elucidating the structure-function relationship and determining the best approach for material preparation and functionalization. Carbonaceous systems such as cellulose are also studied via Raman spectroscopy to interrogate the viability of cellulose nanocrystals as stabilizing agents in emulsions with a host of commercial and industrial applications. Emissive materials have near-limitless applications depending on the region in which they emit. Higher energy emission from metal-organic frameworks (MOFs) in the ultraviolet and visible regions is studied via steady-state and time-resolved photoluminescence. MOFs are frequently used in optoelectronic devices, and work herein provides insight into the three-dimensional framework of such materials. Lower energy emission in the near-infrared (NIR) region is the target for small molecule fluorophores with bioimaging applications. These molecules allow for higher resolution imaging compared to shorter wavelength emitters, but suffer from multiple drawbacks largely related to the Energy Gap law. Unique approaches to circumvent such drawbacks are investigated using a combination of photoluminescence and femtosecond transient absorption spectroscopy (fsTAS). Finally, a series of donor-bridge-acceptor (D-B-A) molecules with charge-transfer capabilities are presented in the context of their use in dye-sensitize solar cells (DSCs). Solar energy capture is a pressing goal as the world shifts from fossil fuels to clean, renewable energy generation. Using fsTAS, the structure function relationship of dyes with DSC applications is probed. Specifically, the effects of proaromaticity in the bridging unit is investigated through a combination of both quantum computational and photophysical data

Effects of Nanoaggregation On Isoindigo-Based Fluorophores For Near-Infrared Bioimaging Applications

In this work, we have taken a donor–acceptor–donor (D–A–D) fluorophore (II-EDOT-TPA) and encapsulated it using a linear dendritic block copolymer (LDBC). In parallel, a polyethylene glycol derivative (PEG-II-EDOT-TPA) was synthesized. The self-assembly and colloidal properties of both nanoaggregates were comparatively assessed. Photophysical and morphological characterization of the LDBC encapsulated II-EDOT-TPA and PEG-II-EDOT-TPA nanoaggregates was performed, which showed the photophysical and morphological properties differed greatly when comparing the two. Both nanoaggregate types were incubated with HEK-293 cells in order to measure cell viability and perform confocal fluorescence microscopy. Minimal cytotoxicity values (\u3c20%) were seen with the two nanoaggregate forms, while both types of nanoaggregates were found to accumulate into the lysosomes of the HEK-293 cells. This work provides fascinating insights into NIR fluorophore design and methods to effectively alter the photophysical and morphological properties of the nanoaggregates for bio-imaging purposes

Cross-linking Poly(caprolactone)–Polyamidoamine Linear Dendritic Block Copolymers for Theranostic Nanomedicine

This study represents a comparative analysis of the solution behavior and self-assembly pattern of two linear dendritic block copolymers (LDBCs) composed of a generation 3 polyamidoamine (PAMAM) dendron as the dendritic block and poly(caprolactone) (PCL) as the linear block, the latter of which is modified with pendant phenyl groups. Phenyl substituents were introduced to induce physical cross-linking in LDBC nanoparticles via π–π stacking. A synthetic strategy was developed to access phenyl substituted LDBCs through an ε-caprolactone monomer derivative followed by ring-opening polymerization to form a library of LDBCs with yields above 83%. Polymersome-like nanoparticles were observed in water with a 74.4 nm average diameter. Cross-linked LDBC nanoparticles demonstrated a 37.1% relative decrease in the critical aggregation concentration (CAC) and a 27.3–41.2% relative increase of hydrophobic loading efficiency relative to unsubstituted LDBCs. Nanoparticles loaded with a potential photothermal agent (phenyl indolizine-C5 (C5)) showed a photothermal efficiency of 49.4% with a heating temperature of 44.4 °C. These nanoparticles were efficiently loaded into HEK293 cells with cell viability above 87.5% at the highest concentration. Upon illumination with red light, nanoparticles loaded with photothermal agent were able to induce cell death in cancer cells. This work suggests that the phenyl substituted LDBCs form nanoparticles with enhanced stability and loading efficiencies compared to conventional nonphenylated systems and display a greater potential to be used as nanocarriers in theranostic nanomedicine