111 research outputs found

    Feedstock blending as a strategy for hydrothermal liquefaction: lipid-rich scum from primary sedimentation and wastewater sludge

    Get PDF
    One salient advantage of hydrothermal liquefaction (HTL) is the ability to process diverse feedstocks individually or as blends. This creates an opportunity for using wet organic waste feedstocks that in many cases pose a disposal liability. The low cost associated with the feedstock enables cost-effective deployment of smaller, decentralized processing plants that match the geographic availability of wet waste resources. Two underutilized sources of wet waste biomass are wastewater sludge and fats, oils, and greases (FOG). In the United States, these each represent about 20% of the total HTL biocrude production potential from wet wastes. In this study, the selected FOG stream is decanted scum from the primary sedimentation operation of the same wastewater treatment plant (WWTP) that provided the sludge. Among the types of FOG, wastewater scum is one of the more complex and challenging. Scum contains entrained water, plant matter like leaves and seeds, and bits of garbage (paper and plastic). For most other processes to access the lipids in scum, some combination of heating, filtering, and solvent extraction would be required, leading to costly and/or inefficient recovery. HTL is preferable because it is a wet process and the scum can be blended directly to capture the whole energy content in the blended feed. Using a blend of primary and secondary sludge from Central Contra Costa Sanitary District (CCCSD) and decanted scum from CCCSD primary sedimentation as the source of FOG, a blend of sludge and scum was successfully prepared and processed in a bench scale continuous flow HTL system. A total of 54 L of blended slurry was converted to 4.2 L of biocrude oil. The scum was blended with the sludge such that it represented 20 wt% of the total dry, ash-free (daf) solids in the feed. The resulting biocrude had a much lower density (0.95 g/cm3) than the biocrude from CCCSD sludge alone (0.99 g/cm3) leading to improved gravity separation from the aqueous phase. The biocrude was also lower in moisture. During the oral presentation, the focus will be on the process of feedstock selection, evaluation, and characteristics including detailed steps and equipment used to format the blended feedstock for use in the HTL reactor system. The poster will include data for the integrated process including mass balance, yields, and characterization of products

    Chiasma

    Get PDF
    Newspaper reporting on events at the Boston University School of Medicine in the 1960s

    Targeted Greybox Fuzzing with Static Lookahead Analysis

    Full text link
    Automatic test generation typically aims to generate inputs that explore new paths in the program under test in order to find bugs. Existing work has, therefore, focused on guiding the exploration toward program parts that are more likely to contain bugs by using an offline static analysis. In this paper, we introduce a novel technique for targeted greybox fuzzing using an online static analysis that guides the fuzzer toward a set of target locations, for instance, located in recently modified parts of the program. This is achieved by first semantically analyzing each program path that is explored by an input in the fuzzer's test suite. The results of this analysis are then used to control the fuzzer's specialized power schedule, which determines how often to fuzz inputs from the test suite. We implemented our technique by extending a state-of-the-art, industrial fuzzer for Ethereum smart contracts and evaluate its effectiveness on 27 real-world benchmarks. Using an online analysis is particularly suitable for the domain of smart contracts since it does not require any code instrumentation---instrumentation to contracts changes their semantics. Our experiments show that targeted fuzzing significantly outperforms standard greybox fuzzing for reaching 83% of the challenging target locations (up to 14x of median speed-up)

    Chiral Phthalocyanines through Axial Coordination

    Get PDF
    A novel approach to axially induce chirality on silicon phthalocyanines via a microwave-assisted route is reported. CD analysis provides spectroscopic evidence that chirality is transferred onto both Soret and Q-bands of the phthalocyanine core. A chiral naphthalenediimide ligand was found to induce the largest Cotton effect on the macrocycle absorptions

    Yukawa Couplings in Heterotic Compactification

    Get PDF
    We present a practical, algebraic method for efficiently calculating the Yukawa couplings of a large class of heterotic compactifications on Calabi-Yau three-folds with non-standard embeddings. Our methodology covers all of, though is not restricted to, the recently classified positive monads over favourable complete intersection Calabi-Yau three-folds. Since the algorithm is based on manipulating polynomials it can be easily implemented on a computer. This makes the automated investigation of Yukawa couplings for large classes of smooth heterotic compactifications a viable possibility.Comment: 38 page

    MetaBase--the wiki-database of biological databases.

    Get PDF
    Biology is generating more data than ever. As a result, there is an ever increasing number of publicly available databases that analyse, integrate and summarize the available data, providing an invaluable resource for the biological community. As this trend continues, there is a pressing need to organize, catalogue and rate these resources, so that the information they contain can be most effectively exploited. MetaBase (MB) (http://MetaDatabase.Org) is a community-curated database containing more than 2000 commonly used biological databases. Each entry is structured using templates and can carry various user comments and annotations. Entries can be searched, listed, browsed or queried. The database was created using the same MediaWiki technology that powers Wikipedia, allowing users to contribute on many different levels. The initial release of MB was derived from the content of the 2007 Nucleic Acids Research (NAR) Database Issue. Since then, approximately 100 databases have been manually collected from the literature, and users have added information for over 240 databases. MB is synchronized annually with the static Molecular Biology Database Collection provided by NAR. To date, there have been 19 significant contributors to the project; each one is listed as an author here to highlight the community aspect of the project

    A Prospective Multicenter Study Evaluating Learning Curves and Competence in Endoscopic Ultrasound and Endoscopic Retrograde Cholangiopancreatography Among Advanced Endoscopy Trainees: The Rapid Assessment of Trainee Endoscopy Skills (RATES) Study

    Get PDF
    Background and aims Based on the Next Accreditation System, trainee assessment should occur on a continuous basis with individualized feedback. We aimed to validate endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) learning curves among advanced endoscopy trainees (AETs) using a large national sample of training programs and to develop a centralized database that allows assessment of performance in relation to peers. Methods ASGE recognized training programs were invited to participate and AETs were graded on ERCP and EUS exams using a validated competency assessment tool that assesses technical and cognitive competence in a continuous fashion. Grading for each skill was done using a 4-point scoring system and a comprehensive data collection and reporting system was built to create learning curves using cumulative sum analysis. Individual results and benchmarking to peers were shared with AETs and trainers quarterly. Results Of the 62 programs invited, 20 programs and 22 AETs participated in this study. At the end of training, median number of EUS and ERCP performed/AET was 300 (range 155-650) and 350 (125-500). Overall, 3786 exams were graded (EUS:1137; ERCP–biliary 2280, pancreatic 369). Learning curves for individual endpoints, and overall technical/cognitive aspects in EUS and ERCP demonstrated substantial variability and were successfully shared with all programs. The majority of trainees achieved overall technical (EUS: 82%; ERCP: 60%) and cognitive (EUS: 76%; ERCP: 100%) competence at conclusion of training. Conclusions These results demonstrate the feasibility of establishing a centralized database to report individualized learning curves and confirm the substantial variability in time to achieve competence among AETs in EUS and ERCP

    Association of genetic variants of the histamine H1 and muscarinic M3 receptors with BMI and HbA1c values in patients on antipsychotic medication

    Get PDF
    Rationale: Antipsychotic affinity for the histamine H1 receptor and the muscarinic M3 receptor have been associated with the side effects weight gain, and development of diabetes, respectively. Objectives: We investigated polymorphisms of the histamine H1 (HRH1) and muscarinic acetylcholine receptor M3 (CHRM3) receptor genes for an association with body mass index (BMI) and glycated hemoglobin (HbA1c). Methods: We included 430 Caucasian patients with a non-affective psychotic disorder using antipsychotics for at least 3 months. Primary endpoints of the study were cross-sectionally measured BMI and HbA1c; secondary endpoints were obesity and hyperglycaemia. Two single-nucleotide polymorphisms (SNPs) in the HRH1 gene, rs346074 and rs346070, and one SNP in the CHRM3 gene, rs3738435, were genotyped. Our primary hypothesis in this study was an interaction between genotype on BMI and antipsychotic affinity for the H1 and M3 receptor. Results: A significant association of interaction between haplotype rs346074-rs346070 and BMI (p value 0.025) and obesity (p value 0.005) in patients using high-H1 affinity antipsychotics versus patients using low-H1 affinity antipsychotics was found. There was no association of CHRM3 gene variant rs3738435 with BMI, and we observed no association with HbA1c or hyperglycaemia in any of the variants. Conclusions: This study, for the first time, demonstrates a significant association between HRH1 variants and BMI in patients with a psychotic disorder using antipsychotics. In future, genotyping of HRH1 variants may help predicting weight gain in patients using antipsychotics

    Architectures of control in consumer product design

    Get PDF
    Copyright @ 2005 Social Services Research GroupThe idea of architectures of control is introduced through examples ranging from urban planning to digital rights management, and the intentions behind their use in consumer products are examined, with reference to case studies of printer cartridges and proposed 'optimum lifetime products.' The reactions of the technical community and consumers themselves are also explored, along with some wider implications for society

    Development of mental health first aid guidelines for Aboriginal and Torres Strait Islander people experiencing problems with substance use: a Delphi study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Problems with substance use are common in some Aboriginal communities. Although problems with substance use are associated with significant mortality and morbidity, many people who experience them do not seek help. Training in mental health first aid has been shown to be effective in increasing knowledge of symptoms and behaviours associated with seeking help. The current study aimed to develop culturally appropriate guidelines for providing mental health first aid to an Aboriginal or Torres Strait Islander person who is experiencing problem drinking or problem drug use (e.g. abuse or dependence).</p> <p>Methods</p> <p>Twenty-eight Aboriginal health experts participated in two independent Delphi studies (n = 22 problem drinking study, n = 21 problem drug use; 15 participated in both). Panellists were presented with statements about possible first aid actions via online questionnaires and were encouraged to suggest additional actions not covered by the content. Statements were accepted for inclusion in the guidelines if they were endorsed by ≥ 90% of panellists as either 'Essential' or 'Important'. At the end of the two Delphi studies, participants were asked to give feedback on the value of the project and their participation experience.</p> <p>Results</p> <p>From a total of 735 statements presented over two studies, 429 were endorsed (223 problem drinking, 206 problem drug use). Statements were grouped into sections based on common themes (n = 7 problem drinking, n = 8 problem drug use), then written into guideline documents. Participants evaluated the Delphi method employed, and the guidelines developed, as useful and appropriate for Aboriginal and Torres Strait Islander people.</p> <p>Conclusions</p> <p>Aboriginal health experts were able to reach consensus about culturally appropriate first aid for problems with substance use. Many first aid actions endorsed in the current studies were not endorsed in previous international Delphi studies, conducted on problem drinking and problem drug use in non-Indigenous people, highlighting the need for culturally specific first aid strategies to be employed when assisting Aboriginal or Torres Strait Islander people.</p
    corecore