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Production of Renewable Fuels and Chemicals from Biomass-Dervied Furan Compounds
Growing concern over the petroleum supply, energy independence, and environmental impacts associated with fossil fuels, has motivated research into the production of renewable fuels and aromatic chemicals from biomass resources. Specifically, furan-based feedstocks such as furfural, 2-methylfuran (MF) and, 2,5-dimethylfuran (DMF) can be derived from biomass and used to produce a wide variety of desired compounds. These furan-based feedstocks are produced by: (a) the hydrolysis of cellulose and hemicellulose form to glucose and xylose, (b) the dehydration of these carbohydrates to form 5-hydroxymethylfurfural (HMF) and furfural, and (c) the reduction of HMF and furfural to DMF, MF, and furan.
The use of a continuous electrocatalytic membrane reactor presents a novel method of selectively hydrogenating furfural at low temperatures without the use of gaseous hydrogen. Conversion of acetone to isopropanol confirmed that the rate of hydrogenation using gaseous hydrogen is comparable to the rate of hydrogenation using water electrolysis. Evaluation of the electrocatalytic hydrogenation of furfural demonstrated an ability to control product selectivity beyond the capability of conventional catalysis. Results indicate that production of renewable “electrofuels” in a PEM reactor, utilizing water electrolysis in the place of hydrogen gas, is a viable alternative to conventional methods.
Diels-Alder cycloaddition of furan-based compounds and ethylene is a promising method of sustainably producing valuable base chemicals. Specific molecules of interest include p-xylene, the feedstock for polyethylene terephthalate (PET); toluene, an important monomer for polyurethane; and benzene, a precursor for polystyrene. The reaction proceeds via a [4+2] Diels-Alder cycloaddition of the furan feedstock and ethylene to produce an oxa-norbornene intermediate, and the subsequent dehydration of the intermediate to form the desired aromatic. 90% selectivity to p-xylene from DMF and 46% selectivity to toluene from MF were achieved over an H-BEA catalyst. Analysis of the reaction rate as a function of catalyst loading revealed two distinct kinetic regimes, whose activation energies correspond with DFT calculated energy barriers for dehydration and cycloaddition rate-limiting steps. Additionally, the reaction network for the MF/ethylene system was expanded to include MF polymers and two isomers of incomplete cycloadduct dehydration. Results demonstrate the complex nature of these reactions and the effect of reaction temperature, catalyst type and loading, and furan feedstock on the product distribution
South Africa
Since the late 1990s, empirical evidence has strongly suggested a gradual increase in drug-related problems and substance abuse (illicit and prescription) in South Africa. Abuse of alcohol is still the primary issue, but other illegal drugs are a very close in any list of social ills for South Africa As in most parts of the world, issues and social problems associated with substance abuse continue to be exacerbated and perpetuated by socio-economic and developmental factors in South Africa. This issue is made worse by the fact that South Africa is one of the world’s largest producers of some illegal drugs such as marijuana. Many international law enforcement experts offer that this location in Africa is the genesis of much of the cannabis trafficked into the Netherlands and the United Kingdom
Every breath you take: An examination of the natural phenomenon of stalking
Everyone is a potential stalker, given the right set of circumstances. There are a vast number of tools readily available—from social media networking to easily accessible websites that provide background checks for a minimal fee—that allow individuals to observe the life (or lives) of whomever they so desire. But what are the innate, essential traits and characteristics of an individual that extends beyond the more normative expression of romantic interest and the general curiosity that is a natural and accepted occurrence for anyone who has ever been infatuated with another? This paper will consider the intentionality and motivation behind stalking, including cyber-stalking, as well as the general obsessive behavior that acts as a proclivity toward stalking and ultimately conclude that everyone is a potential stalker and, further, that we as a society are being conditioned by the media—particularly social media—to accept stalking as a natural phenomenon
Critical Realignment of Humboldt’s “Normal School”: Meeting the Changing Landscape of Teacher Education
Our team of teacher educators share our process for reconceptualizing and reaffirming our vision of teacher education as the larger university shifts focus to that of becoming a polytechnic institution. We developed a heuristic to help us articulate our vision based on our commitments and contexts, and discuss the practical implications that this work has in our coursework and clinical practice. Our vision of the polytechnic teacher centers around four commitments: reflective, relational, reconstructive and research-oriented teaching. These commitments are informed by and exist in relationship with broader concepts of positionality, communities of practice, community partners, and polytechnic perspectives
Report on the 2013 Rapid Assessment Survey of Marine Species at New England Bays and Harbors
Introduced species (i.e., non-native species that have become established in a new location) have increasingly been recognized as a concern as they have become more prevalent in marine and terrestrial environments (Mooney and Cleland 2001; Simberloff et al. 2005). The ability of introduced species to alter population, community, and ecosystem structure and function, as well as cause significant economic damage is well documented (Carlton 1989, 1996b, 2000; Cohen and Carlton 1995; Cohen et al. 1995; Elton 1958; Meinesz et al. 1993; Occhipinti-Ambrogi and Sheppard 2007; Pimentel et al. 2005; Thresher 2000). The annual economic costs incurred from managing the approximately 50,000 introduced species in the United States alone are estimated to be over $120 billion (Pimentel et al. 2005). Having a monitoring network in place to track new introductions and distributional changes of introduced species is critical for effective management, as these efforts may be more successful when species are detected before they have the chance to become established. A rapid assessment survey is one such method for early detection of introduced species. With rapid assessment surveys, a team of taxonomic experts record and monitor marine species–providing a baseline inventory of native, introduced, and cryptogenic (i.e., unknown origin) species (as defined by Carlton 1996a)–and document range expansions of previously identified species. Since 2000, five rapid assessment surveys have been conducted in New England. These surveys focus on recording species at marinas, which often are in close proximity to transportation vectors (i.e., recreational boats). Species are collected from floating docks and piers because these structures are accessible regardless of the tidal cycle. Another reason for sampling floating docks and other floating structures is that marine introduced species are often found to be more prevalent on artificial surfaces than natural surfaces (Glasby and Connell 2001; Paulay et al. 2002). The primary objectives of these surveys are to: (1) identify native, introduced, and cryptogenic marine species, (2) expand on data collected in past surveys, (3) assess the introduction status and range extensions of documented introduced species, and (4) detect new introductions. This report presents the introduced, cryptogenic, and native species recorded during the 2013 survey
Prostate cancer survivorship essentials for men with prostate cancer on androgen deprivation therapy: Protocol for a randomised controlled trial of a tele-based nurse-led survivorship care intervention (PCEssentials hormone therapy study)
Introduction Androgen deprivation therapy (ADT) is commonly used to treat men with locally advanced or metastatic prostate cancer. Men receiving ADT experience numerous side effects and frequently report unmet supportive care needs. An essential part of quality cancer care is survivorship care. To date, an optimal effective approach to survivorship care for men with prostate cancer on ADT has not been described. This protocol describes a randomised trial of tele-based nurse-led survivorship that addresses this knowledge gap: (1) determine the effectiveness of a nurse-led survivorship care intervention (PCEssentials), relative to usual care, for improving health-related quality of life (HR-QoL) in men with prostate cancer undergoing ADT and (2) evaluate PCEssentials implementation strategies and outcomes, including cost-effectiveness, compared with usual care. Methods and analysis This is an effectiveness-implementation hybrid (type 1) trial with participants randomised to one of two arms: (1) minimally enhanced usual care and (2) nurse-led prostate cancer survivorship essentials (PCEssentials) delivered over four tele-based sessions, with a booster session 5 months after session 1. Eligible participants are Australian men with prostate cancer commencing ADT and expected to be on ADT for a minimum of 12 months. Participants are followed up at 3, 6 and 12 months postrecruitment. Primary outcomes are HR-QoL and self-efficacy. Secondary outcomes are psychological distress, insomnia, fatigue and physical activity. A concurrent process evaluation with participants and study stakeholders will be undertaken to determine effectiveness of delivery of PCEssentials. Ethics and dissemination Ethics approval was obtained from the Metro South Health HREC (HREC/2021/QMS/79429). All participants are required to provide written informed consent. Outcomes of this trial will be published in peer-reviewed journals. The findings will be presented at conferences and meetings, local hospital departments, participating organisations/clinical services, and university seminars, and communicated at community and consumer-led forums. Trial registration number ACTRN12622000025730
Report on the 2013: Rapid assessment survey of marine species at New England Bays and Harbors
Introduced species (i.e., non-native species that have become established in\ud
a new location) have increasingly been recognized as a concern as they have\ud
become more prevalent in marine and terrestrial environments (Mooney and\ud
Cleland 2001; Simberloff et al. 2005). The ability of introduced species to alter\ud
population, community, and ecosystem structure and function, as well as\ud
cause significant economic damage is well documented (Carlton 1989, 1996b,\ud
2000; Cohen and Carlton 1995; Cohen et al. 1995; Elton 1958; Meinesz et al.\ud
1993; Occhipinti-Ambrogi and Sheppard 2007; Pimentel et al. 2005; Thresher\ud
2000). The annual economic costs incurred from managing the approximately\ud
50,000 introduced species in the United States alone are estimated to be over\ud
$120 billion (Pimentel et al. 2005).\ud
Having a monitoring network in place to track new introductions and\ud
distributional changes of introduced species is critical for effective\ud
management, as these efforts may be more successful when species are\ud
detected before they have the chance to become established. A rapid\ud
assessment survey is one such method for early detection of introduced\ud
species. With rapid assessment surveys, a team of taxonomic experts\ud
record and monitor marine species–providing a baseline inventory of\ud
native, introduced, and cryptogenic (i.e., unknown origin) species (as\ud
defined by Carlton 1996a)–and document range expansions of previously\ud
identified species.\ud
Since 2000, five rapid assessment surveys have been conducted in New\ud
England. These surveys focus on recording species at marinas, which often\ud
are in close proximity to transportation vectors (i.e., recreational boats).\ud
Species are collected from floating docks and piers because these structures\ud
are accessible regardless of the tidal cycle. Another reason for sampling floating\ud
docks and other floating structures is that marine introduced species are often\ud
found to be more prevalent on artificial surfaces than natural surfaces (Glasby\ud
and Connell 2001; Paulay et al. 2002). The primary objectives of these surveys\ud
are to: (1) identify native, introduced, and cryptogenic marine species,\ud
(2) expand on data collected in past surveys, (3) assess the introduction status\ud
and range extensions of documented introduced species, and (4) detect new\ud
introductions. This report presents the introduced, cryptogenic, and native\ud
species recorded during the 2013 survey.CZM through NOAA NA13NOS4190040MIT Sea Grant through NOAA NA10OAR4170086
EZH2 inhibition reactivates epigenetically silenced FMR1 and normalizes molecular and electrophysiological abnormalities in fragile X syndrome neurons
Fragile X Syndrome (FXS) is a neurological disorder caused by epigenetic silencing of the FMR1 gene. Reactivation of FMR1 is a potential therapeutic approach for FXS that would correct the root cause of the disease. Here, using a candidate-based shRNA screen, we identify nine epigenetic repressors that promote silencing of FMR1 in FXS cells (called FMR1 Silencing Factors, or FMR1- SFs). Inhibition of FMR1-SFs with shRNAs or small molecules reactivates FMR1 in cultured undifferentiated induced pluripotent stem cells, neural progenitor cells (NPCs) and post-mitotic neurons derived from FXS patients. One of the FMR1-SFs is the histone methyltransferase EZH2, for which an FDA-approved small molecule inhibitor, EPZ6438 (also known as tazemetostat), is available. We show that EPZ6438 substantially corrects the characteristic molecular and electrophysiological abnormalities of cultured FXS neurons. Unfortunately, EZH2 inhibitors do not efficiently cross the blood-brain barrier, limiting their therapeutic use for FXS. Recently, antisense oligonucleotide (ASO)-based approaches have been developed as effective treatment options for certain central nervous system disorders. We therefore derived efficacious ASOs targeting EZH2 and demonstrate that they reactivate FMR1 expression and correct molecular and electrophysiological abnormalities in cultured FXS neurons, and reactivate FMR1 expression in human FXS NPCs engrafted within the brains of mice. Collectively, our results establish EZH2 inhibition in general, and EZH2 ASOs in particular, as a therapeutic approach for FXS
Discovery of an intermediate-luminosity red transient in M51 and its likely dust-obscured, infrared-variable progenitor
We present the discovery of an optical transient (OT) in Messier 51,
designated M51 OT2019-1 (also ZTF19aadyppr, AT 2019abn, ATLAS19bzl), by the
Zwicky Transient Facility (ZTF). The OT rose over 15 days to an observed
luminosity of (), in the
luminosity gap between novae and typical supernovae (SNe). Spectra during the
outburst show a red continuum, Balmer emission with a velocity width of
km s, Ca II and [Ca II] emission, and absorption features
characteristic of an F-type supergiant. The spectra and multiband light curves
are similar to the so-called "SN impostors" and intermediate-luminosity red
transients (ILRTs). We directly identify the likely progenitor in archival
Spitzer Space Telescope imaging with a m luminosity of
and a color redder than 0.74 mag, similar
to those of the prototype ILRTs SN 2008S and NGC 300 OT2008-1. Intensive
monitoring of M51 with Spitzer further reveals evidence for variability of the
progenitor candidate at [4.5] in the years before the OT. The progenitor is not
detected in pre-outburst Hubble Space Telescope optical and near-IR images. The
optical colors during outburst combined with spectroscopic temperature
constraints imply a higher reddening of mag and higher
intrinsic luminosity of
() near peak than seen in previous ILRT
candidates. Moreover, the extinction estimate is higher on the rise than on the
plateau, suggestive of an extended phase of circumstellar dust destruction.
These results, enabled by the early discovery of M51 OT2019-1 and extensive
pre-outburst archival coverage, offer new clues about the debated origins of
ILRTs and may challenge the hypothesis that they arise from the
electron-capture induced collapse of extreme asymptotic giant branch stars.Comment: 21 pages, 5 figures, published in ApJ
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