368 research outputs found

    Laboratory Scale Investigations of Potential Odour Reduction Strategies in Biosolids

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    This study investigated sources of odours from biosolids produced from a Western Australian wastewater treatment plant and examined potential odour reduction strategies on a laboratory scale. Odour reduction methods that were trialled included chemical additions and reduction of centrifuge speed. Chemical addition trials were conducted by adding alum, polyaluminium chloride or ferric chloride to digested sludge that had been sampled prior to the dewatering stage. Trials of chemical addition (alum) to plant dewatered cake were also undertaken. The impact of reducing centrifuge speed on biosolids odour was also investigated using a laboratory scale centrifuge calibrated to operate such that the shear forces on the sample would, as closely as possible, represent those on the plant. To identify the odorous compounds present in biosolids and to assess the effectiveness of the odour reduction measures, headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS SPME-GC-MS) methods were developed. Target odour compounds included volatile sulphur compounds (e.g. DMS, DMDS, DMTS) and other volatile organic compounds (toluene, thylbenzene, styrene, p-cresol, indole, skatole and geosmin). In our laboratory trials, aluminium sulphate added to digested sludge prior to dewatering offered the best odour reduction strategy among the options that were investigated, resulting in approximately 40% reduction in peak concentration of the total volatile organic sulphur compounds (TVOSC), relative to a control sample

    Odour reduction strategies for biosolids produced from a Western Australian wastewater treatment plant: Results from Phase I laboratory trials

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    This study investigated sources of odours from biosolids produced from a Western Australian wastewater treatment plant and examined possible strategies for odour reduction, specifically chemical additions and reduction of centrifuge speed on a laboratory scale. To identify the odorous compounds and assess the effectiveness of the odour reduction measures trialled in this study, headspace solid-phase microextraction gas chromatography-mass spectrometry (HS SPME-GC-MS) methods were developed. The target odour compounds included volatile sulphur compounds (e.g. dimethyl sulphide, dimethyl disulphide and dimethyl trisulphide) and other volatile organic compounds (e.g. toluene, ethylbenzene, styrene, p-cresol, indole and skatole). In our laboratory trials, aluminium sulphate added to anaerobically digested sludge prior to dewatering offered the best odour reduction strategy amongst the options that were investigated, resulting in approximately 40% reduction in the maximum concentration of the total volatile organic sulphur compounds, relative to control

    The Bromodomains of the mammalian SWI/SNF (mSWI/SNF) ATPases Brahma (BRM) and Brahma Related Gene 1 (BRG1) promote chromatin interaction and are critical for skeletal muscle differentiation

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    Skeletal muscle regeneration is mediated by myoblasts that undergo epigenomic changes to establish the gene expression program of differentiated myofibers. mSWI/SNF chromatin remodeling enzymes coordinate with lineage-determining transcription factors to establish the epigenome of differentiated myofibers. Bromodomains bind to acetylated lysines on histone N-terminal tails and other proteins. The mutually exclusive ATPases of mSWI/SNF complexes, BRG1 and BRM, contain bromodomains with undefined functional importance in skeletal muscle differentiation. Pharmacological inhibition of mSWI/SNF bromodomain function using the small molecule PFI-3 reduced differentiation in cell culture and in vivo through decreased myogenic gene expression, while increasing cell cycle-related gene expression and the number of cells remaining in the cell cycle. Comparative gene expression analysis with data from myoblasts depleted of BRG1 or BRM showed that bromodomain function was required for a subset of BRG1- and BRM-dependent gene expression. Reduced binding of BRG1 and BRM after PFI-3 treatment showed that the bromodomain is required for stable chromatin binding at target gene promoters to alter gene expression. Our findings demonstrate that mSWI/SNF ATPase bromodomains permit stable binding of the mSWI/SNF ATPases to promoters required for cell cycle exit and establishment of muscle-specific gene expression

    Preoperative Predictors of Arthroscopic Partial Meniscectomy Outcomes: The APM Index Score

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    Problem Statement: - Arthroscopic partial meniscectomy (APM) has been shown to be the most common meniscal surgical treatment in the United States - Pre-op risk factors known to contribute to poor outcomes after APM: Symptom duration and radiographic OA at baseline - Factors with no conclusive effect on post-op outcomes: Baseline knee functional score, location of meniscal tear, BMI, activity level, age, sex, and chondral damage on MRI Project AIM: To create an index score using easily available preoperative risk factors such as Kellgren-Lawrence (KL) grade, age, duration of symptoms, BMI, activity level, and preoperative outcome scores to predict the likelihood of favorable outcomes after APM.https://jdc.jefferson.edu/aoa_research_symposium_posters/1003/thumbnail.jp

    The targeted delivery of multicomponent cargos to cancer cells by nanoporous particle-supported lipid bilayers.

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    Encapsulation of drugs within nanocarriers that selectively target malignant cells promises to mitigate side effects of conventional chemotherapy and to enable delivery of the unique drug combinations needed for personalized medicine. To realize this potential, however, targeted nanocarriers must simultaneously overcome multiple challenges, including specificity, stability and a high capacity for disparate cargos. Here we report porous nanoparticle-supported lipid bilayers (protocells) that synergistically combine properties of liposomes and nanoporous particles. Protocells modified with a targeting peptide that binds to human hepatocellular carcinoma exhibit a 10,000-fold greater affinity for human hepatocellular carcinoma than for hepatocytes, endothelial cells or immune cells. Furthermore, protocells can be loaded with combinations of therapeutic (drugs, small interfering RNA and toxins) and diagnostic (quantum dots) agents and modified to promote endosomal escape and nuclear accumulation of selected cargos. The enormous capacity of the high-surface-area nanoporous core combined with the enhanced targeting efficacy enabled by the fluid supported lipid bilayer enable a single protocell loaded with a drug cocktail to kill a drug-resistant human hepatocellular carcinoma cell, representing a 10(6)-fold improvement over comparable liposomes

    Challenges and support needs of parents and children when a parent is at end of life: A systematic review

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    Background: Preparing children for the death of a parent is challenging. Parents are often uncertain if and how to communicate and support their children. Many parents feel it is protecting their children by not telling them about the prognosis. Children less prepared for parental death from a terminal illness are more susceptive to later adversities. To facilitate coping and moderate for such adversities, there is a need to gain insight and understand the experience and challenges confronted by families. Aim: This review synthesised evidence on the experiences of parents and children when a parent is at end of life to discern their challenges, support needs and factors that facilitated good practice. Design: Mixed-methods systematic review. Data sources: Four electronic databases (CINAHL, PubMed, PsycINFO and Ovid MEDLINE) using MeSH terms and word searches in October 2018. Studies were not limited by year of publication, language or country. Grey literature searches were also completed on Google Scholar and OpenGrey. Results: In all, 7829 records were identified; 27 qualitative and 0 quantitative studies met the inclusion criteria. Eight descriptive themes were identified, further categorised into two broad themes: (1) barriers and facilitators in sharing the news that a parent is dying and (2) strategies to manage the changing situation. Conclusion: Lack of understanding in relation to the parent’s prognosis, denial and feeling ill-equipped were suggested as barriers for parents to share the news with their children. Engagement with social networks, including extended family relatives and peers, and maintaining routines such as attending school were suggested supportive by parents and children. Findings are limited primarily to White, middle-class two-parent families. A number of areas for future research are identified.</p

    Versatile Coordination of Cyclopentadienyl-Arene Ligands and Its Role in Titanium-Catalyzed Ethylene Trimerization

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    Cationic titanium(IV) complexes with ansa-(η5-cyclopentadienyl,η6-arene) ligands were synthesized and characterized by X-ray crystallography. The strength of the metal-arene interaction in these systems was studied by variable-temperature NMR spectroscopy. Complexes with a C1 bridge between the cyclopentadienyl and arene moieties feature hemilabile coordination behavior of the ligand and consequently are active ethylene trimerization catalysts. Reaction of the titanium(IV) dimethyl cations with CO results in conversion to the analogous cationic titanium(II) dicarbonyl species. Metal-to-ligand backdonation in these formally low-valent complexes gives rise to a strongly bonded, partially reduced arene moiety. In contrast to the η6-arene coordination mode observed for titanium, the more electron-rich vanadium(V) cations [cyclopentadienyl-arene]V(NiPr2)(NC6H4-4-Me)+ feature η1-arene binding, as determined by a crystallographic study. The three different metal-arene coordination modes that we experimentally observed model intermediates in the cycle for titanium-catalyzed ethylene trimerization. The nature of the metal-arene interaction in these systems was studied by DFT calculations.
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