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Emerging Technologies for the Production of Renewable Liquid Transport Fuels from Biomass Sources Enriched in Plant Cell Walls
No full textThis is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Plant cell walls are composed predominantly of cellulose, a range of non-cellulosic polysaccharides and lignin. The walls account for a large proportion not only of crop residues such as wheat straw and sugarcane bagasse, but also of residues of the timber industry and specialist grasses and other plants being grown specifically for biofuel production. The polysaccharide components of plant cell walls have long been recognized as an extraordinarily large source of fermentable sugars that might be used for the production of bioethanol and other renewable liquid transport fuels. Estimates place annual plant cellulose production from captured light energy in the order of hundreds of billions of tons. Lignin is synthesized in the same order of magnitude and, as a very large polymer of phenylpropanoid residues, lignin is also an abundant, high energy macromolecule. However, one of the major functions of these cell wall constituents in plants is to provide the extreme tensile and compressive strengths that enable plants to resist the forces of gravity and a broad range of other mechanical forces. Over millions of years these wall constituents have evolved under natural selection to generate extremely tough and resilient biomaterials. The rapid degradation of these tough cell wall composites to fermentable sugars is therefore a difficult task and has significantly slowed the development of a viable lignocellulose-based biofuels industry. However, good progress has been made in overcoming this so-called recalcitrance of lignocellulosic feedstocks for the biofuels industry, through modifications to the lignocellulose itself, innovative pre-treatments of the biomass, improved enzymes and the development of superior yeasts and other microorganisms for the fermentation process. Nevertheless, it has been argued that bioethanol might not be the best or only biofuel that can be generated from lignocellulosic biomass sources and that hydrocarbons with intrinsically higher energy densities might be produced using emerging and continuous flow systems that are capable of converting a broad range of plant and other biomasses to bio-oils through so-called ‘agnostic’ technologies such as hydrothermal liquefaction. Continued attention to regulatory frameworks and ongoing government support will be required for the next phase of development of internationally viable biofuels industries
Identification of the Main Intermediate Precursor of L-Ergothioneine Biosynthesis in Human Biological Specimens
Get PDF© 2016 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC-BY) license (http://creativecommons.org/licenses/by/4.0/).A capillary electrophoresis coupled to tandem mass spectrometry (CE–MS/MS) has been used to make a qualitative determination of hercynine—the main precursor of l-ergothioneine biosynthesis—in some key human biological specimens, such as urine, whole blood, plasma, and saliva. From semiquantitative analysis results, the highest concentrations of hercynine were detected in saliva and whole blood, whereas much lower concentrations were measured in urine and plasma. Whole blood was the biological matrix with the highest concentration of l-ergothioneine followed by plasma, saliva, and urine. The antioxidant effects attributed to l-ergothioneine, along with its peculiar antioxidant mechanism, offer a possible explanation for the presence of the hercynine, as well as its concentration, in the considered biological matrices. View Full-Tex
Grouping and aggregation of ligand protected Au9 clusters on TiO2 nanosheets
No full textOpen Access Article. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.Atomically precise chemically synthesised Au clusters, in the form of [Au9(PPh3)8](NO3)3, were deposited onto titania nanosheets after UV pre-treatment of the substrate and examined with scanning tunneling microscopy (STM), atomic force microscopy (AFM) and synchrotron X-ray photoelectron spectroscopy (XPS) before and after heat treatment. The STM, AFM and XPS results complement each other. AFM was performed to determine the height of the deposited species and their dispersion on titania nanosheets. STM shows groups of clusters that at least partially consist of individual clusters both before and after annealing. STM cannot exclude the existence of individual clusters on the titania nanosheets outside the groups. XPS shows that before annealing the Au clusters are attached to the titania surface as individual clusters thus as clusters with non-agglomerated cluster cores. After annealing, both individual and agglomerated clusters are found on the surface. The combination of AFM, STM and XPS shows that the groups formed by the clusters consist of individual and agglomerated clusters
Plasma enhanced vortex fluidic device manipulation of graphene oxide
No full textOpen Access Article. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.A vortex fluid device (VFD) with non-thermal plasma liquid processing within dynamic thin films has been developed. This plasma–liquid microfluidic platform facilitates chemical processing which is demonstrated through the manipulation of the morphology and chemical character of colloidal graphene oxide in water
Hydrogen peroxide preferentially activates capsaicin-sensitive high threshold afferents via TRPA1 channels in the guinea pig bladder
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Polygenic interactions with environmental adversity in the aetiology of major depressive disorder
No full text© Cambridge University Press 2015. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited.Major depressive disorder (MDD) is a common and disabling condition with well-established heritability and environmental risk factors. Gene–environment interaction studies in MDD have typically investigated candidate genes, though the disorder is known to be highly polygenic. This study aims to test for interaction between polygenic risk and stressful life events (SLEs) or childhood trauma (CT) in the aetiology of MDD.
The RADIANT UK sample consists of 1605 MDD cases and 1064 controls with SLE data, and a subset of 240 cases and 272 controls with CT data. Polygenic risk scores (PRS) were constructed using results from a mega-analysis on MDD by the Psychiatric Genomics Consortium. PRS and environmental factors were tested for association with case/control status and for interaction between them.
PRS significantly predicted depression, explaining 1.1% of variance in phenotype (p = 1.9 × 10−6). SLEs and CT were also associated with MDD status (p = 2.19 × 10−4 and p = 5.12 × 10−20, respectively). No interactions were found between PRS and SLEs. Significant PRSxCT interactions were found (p = 0.002), but showed an inverse association with MDD status, as cases who experienced more severe CT tended to have a lower PRS than other cases or controls. This relationship between PRS and CT was not observed in independent replication samples.
CT is a strong risk factor for MDD but may have greater effect in individuals with lower genetic liability for the disorder. Including environmental risk along with genetics is important in studying the aetiology of MDD and PRS provide a useful approach to investigating gene–environment interactions in complex traits
Impaired bolus clearance in asymptomatic older adults during high resolution impedance manometry
Get PDF12892This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving. This author accepted manuscript is made available following 12 month embargo from date of publication (26 June 2016) in accordance with the publisher's copyright policy.Background
Dysphagia becomes more common in old age. We performed high-resolution impedance manometry (HRIM) in asymptomatic healthy adults (including an older cohort >80 years) to assess HRIM findings in relation to bolus clearance.
Methods
Esophageal HRIM was performed in a sitting posture in 45 healthy volunteers (n = 30 young control, mean age 37 ± 11 years and n = 15 older subjects aged 85 ± 4 years) using a 3.2-mm solid-state catheter (Solar GI system; MMS, Enschede, The Netherlands) with 25 pressure (1-cm spacing) and 12 impedance segments (2-cm intervals). Five swallows each of 5- and 10-mL liquid and viscous bolus were performed and analyzed using esophageal pressure topography metrics and Chicago classification criteria as well as pressure-flow parameters. Bolus transit was determined using standard impedance criteria. A p-value <0.05 was considered significant.
Key Results
Impaired bolus clearance occurred more frequently in asymptomatic older subjects compared with young controls (YC) during liquid (40 vs 18%, χ2 = 4.935; p < 0.05) and viscous (60 vs 17%; χ2 = 39.08; p < 0.001) swallowing. Longer peristaltic breaks (p < 0.05) and more rapid peristalsis (L: p < 0.004, V: p = 0.003) occurred in the older cohort, with reduced impedance-based clearance for both bolus consistencies (L: p < 0.05, V: p < 0.001). Decreased peristaltic vigor (distal contractile integral <450 mmHg/s/cm) was associated with reduced liquid clearance in both age groups (p < 0.001) and of viscous swallows in the older group (p < 0.001). Impedance ratio, a marker of bolus retention, was increased in older subjects during liquid (p = 0.002) and viscous (p < 0.001) swallowing.
Conclusions & Inferences
Impaired liquid and viscous bolus clearance, esophageal pressure topography, and pressure-flow changes were seen in asymptomatic older subjects
Manipulating three-dimensional gel network entanglement by thin film shearing
No full textOpen Access Article. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.Vortex fluidic mediated shearing of supramolecular gels in thin films leads to complete disruption of fluorous bis-urea derived gels. Hydrocarbon analogues however, are only partially disrupted, which emphasizes the resistance of non-fluorous bis-urea gelators towards shear. The gel structures have been studied by combining the thin film shearing with small angle neutron scattering. This technique represents a novel approach to study the effects of external stimuli on self-assembled supramolecular gel networks
Angiopoietin receptor TEK mutations underlie primary congenital glaucoma with variable expressivity
Get PDFPublished version made available in accordance publisher policy. Article available freely at PubMed Central (PMC). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4922711/Primary congenital glaucoma (PCG) is a devastating eye disease and an important cause of childhood blindness worldwide. In PCG, defects in the anterior chamber aqueous humor outflow structures of the eye result in elevated intraocular pressure (IOP); however, the genes and molecular mechanisms involved in the etiology of these defects have not been fully characterized. Previously, we observed PCG-like phenotypes in transgenic mice that lack functional angiopoietin-TEK signaling. Herein, we identified rare TEK variants in 10 of 189 unrelated PCG families and demonstrated that each mutation results in haploinsufficiency due to protein loss of function. Multiple cellular mechanisms were responsible for the loss of protein function resulting from individual TEK variants, including an absence of normal protein production, protein aggregate formation, enhanced proteasomal degradation, altered subcellular localization, and reduced responsiveness to ligand stimulation. Further, in mice, hemizygosity for Tek led to the formation of severely hypomorphic Schlemm’s canal and trabecular meshwork, as well as elevated IOP, demonstrating that anterior chamber vascular development is sensitive to Tek gene dosage and the resulting decrease in angiopoietin-TEK signaling. Collectively, these results identify TEK mutations in patients with PCG that likely underlie disease and are transmitted in an autosomal dominant pattern with variable expressivity
Men, Work, and Mental Health: A Systematic Review of Depression in Male-dominated Industries and Occupations
Get PDFCopyright © 2016, Occupational Safety and Health Research Institute. Published by Elsevier. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Among men, depression is often unrecognised and untreated. Men employed in male-dominated industries and occupations may be particularly vulnerable. However, efforts to develop tailored workplace interventions are hampered by lack of prevalence data. A systematic review of studies reporting prevalence rates for depression in male dominated workforce groups was undertaken. Studies were included if they were published between 1990 - June 2012 in English, examined adult workers in male-dominated industries or occupations (> 70% male workforce), and used clinically relevant indicators of depression. Twenty studies met these criteria. Prevalence of depression ranged from 0.0% to 28.0%. Five studies reported significantly lower prevalence rates for mental disorders among male-dominated workforce groups than comparison populations, while six reported significantly higher rates. Eight studies additionally found significantly higher levels of depression in male-dominated groups than comparable national data. Overall, the majority of studies found higher levels of depression among workers in male-dominated workforce groups. There is a need to address the mental health of workers in male-dominated groups. The workplace provides an important but often overlooked setting to develop tailored strategies for vulnerable groups