The effect of bubble size on the performance of ebullated bed hydroprocessors

A recent cold-flow study has revealed that modifying gas distributor design in three-phased fluidized beds can have a significant effect on overall phase hold-ups and regime transition velocities, even at equivalent phase velocities. It is conjectured that this can be attributed to changes in the bubble-size distribution within the reactor. This study aims to develop a complete kinetic-hydrodynamic model of a resid hydroprocessing ebullated bed reactor with internal recycle in order to study the effects of bubble size distribution on performance metrics of industrial significance. The model consists of combined catalytic and ther-mal reaction models, phase separation efficiency correlations obtained through CFD modelling, catalyst fouling and deactivation models, boiling-point based Vapour-Liquid Equilibria (VLE) relations, and specialized phase hold-up corre-lations developed for resid hydroprocessing applications. A preliminary hydrodynamic model comparing monodisperse bubble sizes between 0.5 mm and 4 mm has been performed. At the lowest bubble size, gas entrainment (and hence gas hold-up) were maximal, while ideal phase separation was achieved at the largest bubble size. Bed gas hold-ups ranged from 10 % to 40 %. Increased gas entrainment was also associated with a decrease in internal liquid recycle ratio required for design ebullation height. The effect of bubble size was most pronounced near a diameter of 1 mm. Ongoing analysis into the effect of bubble recycle on bed gas phase com-position in a reactive system is being performed. The effect of bubble size on liquid residence time and hence conversion will be studied with the objective of determining the optimal bubble size for maximizing key conversion parameters

When Do People Trust Their Social Groups?

Trust facilitates cooperation and supports positive outcomes in social groups, including member satisfaction, information sharing, and task performance. Extensive prior research has examined individuals' general propensity to trust, as well as the factors that contribute to their trust in specific groups. Here, we build on past work to present a comprehensive framework for predicting trust in groups. By surveying 6,383 Facebook Groups users about their trust attitudes and examining aggregated behavioral and demographic data for these individuals, we show that (1) an individual's propensity to trust is associated with how they trust their groups, (2) smaller, closed, older, more exclusive, or more homogeneous groups are trusted more, and (3) a group's overall friendship-network structure and an individual's position within that structure can also predict trust. Last, we demonstrate how group trust predicts outcomes at both individual and group level such as the formation of new friendship ties.Comment: CHI 201

Investigation of fennel protein extracts by shot-gun Fourier transform ion cyclotron resonance mass spectrometry

A rapid shot-gun method by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) is proposed for the characterization of fennel proteins. After enzymatic digestion with trypsin, few microliters of extract were analyzed by direct infusion in positive ion mode. A custom-made non-redundant fennel-specific proteome database was derived from the well-known NCBI database; additional proteins belonging to recognized allergenic sources (celery, carrot, parsley, birch, and mugwort) were also included in our database, since patients hypersensitive to these plants could also suffer from fennel allergy. The peptide sequence of each protein from that derived list was theoretically sequenced to produce calculated m/z lists of possible m/z ions after tryptic digestions. Then, by using a home-made Matlab algorithm, those lists were matched with the experimental FT-ICR mass spectrum of the fennel peptide mixture. Finally, Peptide Mass Fingerprint searches confirmed the presence of the matched proteins inside the fennel extract with a total of 70 proteins (61 fennel specific and 9 allergenic proteins)

Prosocial behaviour helps to ease physical pain: Longitudinal evidence from Britain

Objective Prior studies suggest that prosocial behaviour can lead to better mental and physical health. Yet little is known about whether engaging in prosocial behaviour contributes to reducing physical pain. The objective of this study is to investigate longitudinal associations of two prosocial behaviours, donating money to charity and/or volunteering time to an organisation, with pain. Methods Data are from the United Kingdom Household Longitudinal Survey (UKHLS, approximate N = 48,000 individuals). Both prosocial behaviours were assessed in 2011 and pain was assessed annually through 2020, according to the extent to which it interfered with respondents' ability to do work. Using a prospective longitudinal study design, linear mixed models examined associations of each prosocial behaviour separately and both combined on pain interference across 10 years of follow-up adjusting for a broad range of covariates including demographics, initial health status, and depression. Results People who did versus did not donate or volunteer reported lower pain interference over 10 years of follow-up (donating b = −0.059, p < 0.001; volunteering b = −0.086, p < 0.001). Individuals who donated more versus less money reported lower pain interference although volunteering more hours was not associated with lower pain interference. Finally, findings suggested that engaging in both donating and volunteering versus neither was associated with lower pain interference over follow-up. Conclusion There is a longitudinal association between donating money to charity and/or volunteering time to an organisation with pain interference with work. Understanding factors that help to reduce pain is relevant for the design of public health policies

Preoperative insulin-like growth factor-binding protein-3 (IGFBP-3) blood level predicts gleason sum upgrading

In this study, we evaluated the ability of preoperative IGFBP-2, IGFBP-3, IL-6, and SIL-6R serum levels to predict Gleason score upgrade in 52 PCa patients

Novel anti-obesity quercetin-derived Q2 prevents metabolic disorders in rats fed with high-fat diet

Objective: Obesity is often accompanied by an increased morbidity and mortality due to an increase of the cardiovascular disease risk factors, diabetes mellitus and dyslipidemia. Research is constantly working on protective molecules against obesity. In the present study, a novel Quercetin derivative Q2 was synthesized to overcome the poor bioavailability and low stability of Quercetin, a natural flavonoid with antioxidative and antiobesity properties. Methods: Rats were fed (12ws) with normodiet (fat:INS; 6.2%), High Fat Diet (fat:60%), HFDINS; +INS; Q2 in water (500INS; nM). Metabolic and anthropometric parameters were measured. 3T3-L1 preadipocytes were incubated with Q2 (1-25μM) and the differentiation program was evaluated by lipid accumulation through ORO staining. Gene and protein expression levels were assessed by RT-PCR and Western blot analysis. Results: Compared to HFD, HFDINS; +INS; Q2 rats showed reduced body weight, abdominal obesity, dyslipidemia and improved glucose tolerance. This is associated to lower adipose and liver modifications compared to hypertrophy and steatosis observed in HFD. In 3T3-L1 cells, lipid accumulation was significantly impaired by treatment with Q2. Indeed, Q2 significantly decreased the expression of the main adipogenic markers, c/EBPα and PPARγ both at mRNA and protein level. Conclusions: Our results indicate that Q2 markedly decreases differentiation of 3T3-L1 preadipocytes and contributes to prevent metabolic disorders as well as adipose and liver alterations typical of severe obesity induced by a HFD

Allergic reactions after vaccination: translating guidelines into clinical practice

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Performance of the Two Aerogel Cherenkov Detectors of the JLab Hall A Hadron Spectrometer

We report on the design and commissioning of two silica aerogel Cherenkov detectors with different refractive indices. In particular, extraordinary performance in terms of the number of detected photoelectrons was achieved through an appropriate choice of PMT type and reflector, along with some design considerations. After four years of operation, the number of detected photoelectrons was found to be noticeably reduced in both detectors as a result of contamination, yellowing, of the aerogel material. Along with the details of the set-up, we illustrate the characteristics of the detectors during different time periods and the probable causes of the contamination. In particular we show that the replacement of the contaminated aerogel and parts of the reflecting material has almost restored the initial performance of the detectors.Comment: 18 pages, 9 Figures, 4 Tables, 44 Reference

Safety of measles, mumps, and rubella vaccine in egg allergy: in vivo and in vitro management

Background: Egg allergy is the second most prevalent form of food allergy in childhood. In spite of the evidence accumulated, inoculating egg allergy children with attenuated vaccines grown on chick embryo cell cultures, such as the measles, mumps, and rubella (MMR) vaccine, is regarded (erroneously) as potentially dangerous or even anaphylactogenic, by many. An issue perceived as particularly conflicting also by Health Professionals. Case presentation: A 15-year-old boy, with a history of severe egg allergy in early infancy, who was still sensitized to egg allergens, including baked egg, had never received MMR vaccination, in fear of possible anaphylaxis, in spite of the fact that this vaccination is mandatory in the first year of life, in Italy. Because of that, he was not allowed to attend school, longer, and was referred to us in order to assess the potential risk of MMR vaccination. Upon thorough allergologic workup, sensitization to MMR vaccine components was excluded by an in vivo approach, consisting in skin prick tests, intradermal tests, and subcutaneous injection test, corroborated by vaccine-specific B-lymphocyte proliferation assay, ex vivo. T-cell proliferation in response to MMR vaccine was also excluded. Eventually, the boy was inoculated with MMR vaccine and was readmitted to school. Conclusions: The diagnostic strategy adopted appears feasible and easy-to-perform and may be adopted in controversial cases (as the one reported), characterized by previous severe allergic reactions to egg. The B-lymphocyte proliferation assay we developed may represent a useful and reliable tool not only in research but also in clinical practice