223 research outputs found

    Numerical simulation of biomass fast pyrolysis in fluidized bed and auger reactors

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    Seeking a clean alternative energy resource is inevitable because of the limited fossil fuel energy resources and greenhouse gas emissions issue. Recently, advances in chemical and fuel processing technologies allow us to convert biomass to energy products with high energy density and value. Fast pyrolysis process is among the promising technologies for converting biomass to bio-oil and combustible gases and has gained substantial attention due to its ability to produce high yields of bio-oil, a valuable liquid which can be further upgraded to transportation fuels. Nonetheless, many obstacles need to be overcome in order to utilize biomass fast pyrolysis effectively and economically. For example, moving to large-scale operations is an important step to lower the capital cost of such processes. However, a detailed understanding of the complex thermo-physical phenomena happening inside the fast pyrolysis reactors is needed for designing and optimizing the process at large scales. In this work, biomass fast pyrolysis is studied in various reactor geometries using a comprehensive numerical framework developed in this study. In this framework, a combination of a flow solver and chemical reaction solver is employed to describe pyrolysis of biomass. A multi-fluid model is used to describe the multiphase hydrodynamics of fast pyrolysis and the kinetic theory of granular flows is used to account for the solid phases. Then, a global pyrolysis reaction mechanism is coupled with the multi-fluid model to build a comprehensive CFD model capable of predicting time-dependent properties of chemically reacting multi-phase flows in pyrolysis process. A time-splitting technique is also employed to couple the flow solver and reaction kinetics. This numerical model is first tested on a bubbling fluidized bed pyrolyzer and validated using experimental data from literature. Simulation results for pure cellulose and red oak pyrolysis in bubbling fluidized bed reactors show good level of agreement with experimental values. Moreover, zero-dimensional modeling of biomass fast pyrolysis is carried out by estimating the vapor residence time in the bubbling fluidized bed reactor simulated in this study. Later, a single-auger reactor is studied using the present CFD model and results are validated using experimental data obtained from the auger reactor experiment at Iowa State University. Finally, the effects of operating conditions on the product yields are investigated in a single-auger reactor. Operating variables including reactor temperature, nitrogen flow rate, biomass feed rate, biomass pre-treatment temperature, reactor length and reactor diameter are varied and their effects are characterized. Numerical results show that extremely high reactor temperatures (\u3e 823 K) favor syngas formation and decrease tar and unreacted biomass yields. While increasing nitrogen flow rate and shorter reactor lengths produced favorable results. Similar to experimental data, numerical simulations also show that using thermally pre-treated biomass results in higher yields of syngas and lower unreacted biomass and tar yields. Simulations indicate that the auger reactor configuration is very sensitive to biomass feed rate, resulting in high yields of unreacted biomass when high biomass feed rates are applied. To address this issue, a single-auger reactor with larger diameter compared to the standard auger is simulated and resulted in substantially lower unreacted biomass yield

    Polynomial extensions of cP-Baer rings

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    Birkenmeier and Heider, in [2], say that a ring R is right cP-Baer if the right annihilator of a cyclic projective right R-module in R is generated by an idempotent. These rings are a generalization of the right p.q.-Baer and abelian rings. Generally, a formal power series ring over one indeterminate, wherein its base ring is right p.q.-Baer, is not necessarily right p.q.-Baer. However, according to [2], if the base ring is right cP-Baer then the power series ring over one indeterminate is right cP-Baer. Following [2], we investigate the transfer of the cP-Baer property between a ring R and various extensions (including skew polynomials, skew Laurent polynomials, skew power series, skew inverse Laurent series, and monoid rings). We also answer a question posed by Birkenmeier and Heider [2] and provide examples to illustrate the results.Comment: 20 page

    Élaboration, faisabilitĂ© et effets d’une formation aux techniques de communication dĂ©rivĂ©es de l’hypnose pour prĂ©venir la douleur et la dĂ©tresse procĂ©durales en pĂ©diatrie

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    Que ce soit pour soigner une blessure, faire des examens mĂ©dicaux, ou pour recevoir des traitements, les enfants subissent plusieurs procĂ©dures mĂ©dicales qui sont associĂ©es Ă  des niveaux importants de douleur et de dĂ©tresse. Plusieurs interventions pharmacologiques et non-pharmacologiques sont utilisĂ©es dans les milieux de soins pĂ©diatriques dans un contexte de gestion de la douleur et de la dĂ©tresse procĂ©durales. Parmi les interventions non-pharmacologiques soutenues empiriquement, la communication dĂ©rivĂ©e de l’hypnose consiste Ă  utiliser des techniques de communication hypnotique sans induction d’une transe. Bien que la littĂ©rature fasse Ă©tat de l’efficacitĂ© des interventions hypnotiques, la majoritĂ© des recherches en pĂ©diatrie Ă©tudie l’efficacitĂ© d’une intervention menĂ©e par un spĂ©cialiste de l’hypnose accompagnant le soignant qui effectue la procĂ©dure. Or, cette façon de faire est trĂšs dispendieuse et n’est pas organisable dans les milieux hospitaliers pĂ©diatriques. Il est donc primordial d’élaborer des formations pour ceux qui prodiguent les soins, comme les infirmiers(Ăšres), afin de leur permettre d’utiliser des techniques de communication hypnotique simples dans leur pratique clinique quotidienne. L’objectif principal de cette thĂšse est d’élaborer une formation aux techniques de communication dĂ©rivĂ©es de l’hypnose clinique pour le personnel infirmier pĂ©diatrique afin de rĂ©duire la douleur et la dĂ©tresse de jeunes patients lors de procĂ©dures mĂ©dicales douloureuses et anxiogĂšnes. La prĂ©sente thĂšse est composĂ©e de trois articles. Les deux premiers articles dĂ©coulent d’une Ă©tude de test de concept et de faisabilitĂ©. Le premier article a comme objectifs d’élaborer une formation aux techniques de communication dĂ©virĂ©es de l’hypnose pour les infirmiers(Ăšres) pĂ©diatriques, d’évaluer leur maĂźtrise des compĂ©tences de communication hypnotique suite Ă  la formation et d’évaluer leur expĂ©rience en ce qui a trait au programme de formation. L’étude de test de concept et de faisabilitĂ© prĂ©-post-suivi, rĂ©alisĂ©e auprĂšs de 6 infirmiĂšres pĂ©diatriques et 33 de leurs patients atteints d’un cancer, a montrĂ© que, suite Ă  une brĂšve formation, les infirmiĂšres maĂźtrisent les compĂ©tences relationnelles et techniques de communication hypnotique et que ces compĂ©tences sont maintenues dans le temps. Les rĂ©sultats ont Ă©galement rĂ©vĂ©lĂ© que deux infirmiĂšres ont augmentĂ© leurs compĂ©tences de communication hypnotique de maniĂšre plus importante que les autres infirmiĂšres. Lors des entretiens individuels, les infirmiĂšres ont identifiĂ© des composantes positives et nĂ©gatives de la formation et ont proposĂ© des suggestions d’amĂ©lioration. Le second article a comme objectif d’évaluer les effets d’une telle formation aux techniques de communication dĂ©rivĂ©es de l’hypnose sur la douleur et la dĂ©tresse procĂ©durales de patients pĂ©diatriques d’une clinique de jour d’HĂ©matologie-Oncologie. Pour l’ensemble de l’échantillon (88 interactions infirmiĂšre-patient chez 22 patients), aucune diffĂ©rence significative n’a Ă©tĂ© observĂ©e au niveau de la douleur et la dĂ©tresse, Ă  l’exception d’une diminution significative de la dĂ©tresse perçue par le parent en post-formation. En explorant l’hĂ©tĂ©rogĂ©nĂ©itĂ© des compĂ©tences des infirmiĂšres au niveau de la douleur et de la dĂ©tresse des patients, des amĂ©liorations significatives ont Ă©tĂ© observĂ©es suite Ă  la formation pour la douleur auto-rapportĂ©e par le patient, la douleur et la dĂ©tresse perçues par le parent et la douleur observĂ©e chez les patients des infirmiĂšres avec une maĂźtrise supĂ©rieure des compĂ©tences. Bien que ces changements observĂ©s au niveau de la douleur et la dĂ©tresse n’ont pas Ă©tĂ© maintenus au suivi, ces derniers peuvent ĂȘtre attribuĂ©s Ă  des changements des compĂ©tences chez les infirmiĂšres. Finalement, sur la base de cette Ă©tude de test de concept et de faisabilitĂ©, une nouvelle formation a Ă©tĂ© Ă©laborĂ©e. Le troisiĂšme article, dĂ©coulant d’une Ă©tude de dĂ©veloppement-raffinement, a comme objectifs d’élaborer une formation manualisĂ©e Ă  la communication dĂ©rivĂ©e de l’hypnose Ă  destination du personnel infirmier pĂ©diatrique, de prĂ©-tester cette formation auprĂšs d’infirmiers(Ăšres) d’oncologie pĂ©diatrique et de raffiner la formation en fonction des suggestions d’amĂ©lioration des infirmiĂšres. La formation manualisĂ©e Rel@x est constituĂ©e de deux sĂ©ances de 4h : une sĂ©ance sur les aspects relationnels et une autre, prĂ©sentant une des deux techniques de communication hypnotique proposĂ©es, l’« endroit agrĂ©able » ou le « gant magique ». Lors du prĂ©-test, cinq infirmiĂšres ont pris part Ă  l’ensemble des sĂ©ances. Les Ă©valuations quantitatives et qualitatives ont rĂ©vĂ©lĂ© que les infirmiĂšres ont apprĂ©ciĂ© la formation. Les infirmiĂšres ont proposĂ© des suggestions d’amĂ©lioration par rapport au contenu, Ă  la forme et au matĂ©riel de la formation, et ces suggestions ont Ă©tĂ© intĂ©grĂ©es Ă  la version finale de la formation. Cette formation Rel@x est maintenant prĂȘte Ă  ĂȘtre testĂ©e dans une Ă©tude pilote.Whether it is to treat an injury, undergo a medical exam, or receive treatment, children go through many medical procedures that are associated with significant levels of pain and distress. Several pharmacological and non-pharmacological interventions are used in pediatric care settings in the context of procedural pain and distress management. Among the empirically supported non-pharmacological interventions, hypnosis-derived communication consists of using hypnotic communication techniques without the induction of a trance. Although the literature shows the efficacy of hypnotic interventions, the majority of research in pediatrics studies the efficacy of an intervention conducted by a hypnosis specialist accompanying the healthcare professional performing the procedure. However, this way of doing is very expensive and cannot be organized in pediatric hospital settings. It is therefore essential to develop training for those who provide care, such as nurses, to enable them to use simple hypnotic communication techniques in their daily clinical practice. This thesis's main objective is to develop a training in communication techniques derived from clinical hypnosis for pediatric nursing personnel to reduce young patients' pain and distress during painful and anxiety-provoking medical procedures. This thesis is composed of three articles. The first two articles stem from a test of concept and feasibility study. The first article aims to develop a training in communication techniques derived from hypnosis for pediatric nurses, to evaluate their mastery of hypnotic communication skills following the training, and to evaluate their experience with the training program. The pre-post follow-up test of concept and feasibility study, conducted with 6 pediatric nurses and 33 of their cancer patients, showed that, following brief training, nurses master the relational and technical hypnotic communication skills and that these skills are maintained over time. Results also revealed that two nurses increased their hypnotic communication skills more importantly than the other nurses. In the individual interviews, nurses identified both positive and negative components of the training and offered suggestions for improvement. The second article aims to evaluate the effects of such hypnosis-derived communication training on pediatric patients' procedural pain and distress in a Hematology-Oncology daycare clinic. For the whole sample (88 nurse-patient interactions among 22 patients), no significant differences were observed for pain and distress, except for a significant decrease in distress perceived by the parent in the post-training. When exploring the heterogeneity of nurses' skills in regard to patient pain and distress, significant improvements were observed following the training for patient's self-reported pain, pain and distress perceived by the parent, and observed pain in patients of nurses with a higher skill mastery. Although these observed changes in pain and distress were not maintained at follow-up, they can be attributed to changes in nurses' skills. Finally, on the basis of this test of concept and feasibility study, a new training was developed. The third article, stemming from a development-refinement study, aims to develop a manualized hypnosis-derived communication training for pediatric nurses, pre-test the training with pediatric oncology nurses, and refine the training based on nurses' suggestions for improvement. The manualized Rel@x training consists of two 4-hour sessions: one session on relational aspects and another, presenting one of the two hypnotic communication techniques proposed, the “pleasant place” or the “magic glove”. During the pre-test, five nurses took part in all the sessions. The quantitative and qualitative evaluations revealed that the nurses appreciated the training. Nurses proposed suggestions for improvement in regards to the training’s content, format and materials, and these suggestions were integrated into the final version of the training. This Rel@x training is now ready to be tested in a pilot study

    Développement et étude de la fidélité inter-juges d'un outil évaluant la communication hypnotique des soignants en oncologie pédiatrique : échelle d'évaluation de la communication hypnotique du CHU Sainte-Justine

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    Introduction : Plusieurs études en oncologie pédiatrique ont démontré que la communication hypnotique permet de diminuer la douleur et la détresse lors de procédures médicales. Bien que l’efficacité des techniques hypnotiques ait été observée, rien ne garantit que les relations observées impliquent une communication hypnotique puisqu’aucun outil évaluant spécifiquement les techniques de communication ne fût utilisé. Objectifs : (1) Développer une échelle évaluant les comportements des soignants lors de l’utilisation de techniques hypnotiques et (2) Analyser la fidélité inter-juges de cette échelle. Méthodologie : Dans le cadre d'une étude d'intervention, l'Échelle d'évaluation de la communication hypnotique du CHU Sainte-Justine (EECH-SJ) fut développée en trois cycles par l’utilisation d’un processus itératif visant à maximiser la spécificité et la clarté. Cinq experts et quatre évaluateurs ont participé au processus de développement. La fidélité inter-juges fut évaluée auprès de quatre évaluateurs sur des enregistrements vidéos capturant des interactions soignant-patient (n=42) sélectionnés aléatoirement. Résultats : Composée de 11 items, l’EECH-SJ est divisée en deux catégories : Relation et Technique. Une excellente fidélité inter-juges a été obtenue pour le score total et les sous-scores dans deux comparaisons inter-juges indépendantes (ICC médiane = 0,879), avec la majorité des items possédant une fidélité inter-juges élevée à parfaite (Kappa médian = 0,847). Conclusion : Les résultats soutiennent la poursuite du travail effectué avec l’EECH-SJ. L'échelle a un bon potentiel pour une utilisation future en pédiatrie afin d’évaluer l'intégrité des formations en communication hypnotique. Ultimement, l’EECH-SJ pourrait favoriser la dissémination de la communication hypnotique en pratique clinique.Introduction: Several Studies in pediatric oncology have shown that hypnotic communication decreases pain and distress during medical procedures. Although the successful effects of hypnotic techniques have been observed, there is no guarantee that the observed relationships involve specifically hypnotic communication as no precise assessment tool was used to evaluate communication techniques. Objectives: (1) To develop a scale assessing healthcare providers’ behaviour when using hypnotic techniques and (2) to evaluate its inter-rater reliability (IRR). Methods: As part of a interventional study, the Sainte-Justine Hypnotic Communication Assessment Scale (SJ-HCAS) was developed in three rounds using an iterative process aiming to maximize specificity and clarity. Five experts and four lay raters participated in the development process. IRR was assessed by four raters in a randomly selected sample of collected video recorded nurse-patient interactions (n=42). Results: Composed of 11 items, the SJ-HCAS is divided into two categories: Relationship and Technique. Excellent IRR was found for the total score and the subscores in two independent inter-rater comparisons (median ICC = 0.879), with most items showing high to perfect IRR (median Kappa = 0.847). Conclusion: The results support further work with the SJ-HCAS. The scale has a good potential for future use in pediatrics to assess integrity of hypnotic communication training. The SJ-HCAS could ultimately promote the dissemination of hypnotic communication in clinical practice

    Development and refinement of Rel@x : a training in hypnosis-derived communication for pediatric nurses to prevent procedural pain

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    IntroductionStudies in pediatric oncology have shown that hypnosis effectively reduces patients’ pain and distress during painful procedures. This remains underutilized in the healthcare system due to the staff cost and availability of hypnotherapists. To develop the use of hypnosis-derived communication, we aimed to train nurses to use hypnosis-derived communication while they perform painful procedures. ObjectivesThis study aimed to (1) develop a brief training in hypnosis-derived communication for pediatric nurses named Rel@x, (2) pretest the training with experienced pediatric oncology nurses, and (3) refine the training based on nurses’ suggestions. MethodsThe Rel@x training consists of two 4-h sessions: one related to relational aspects and another one presenting one of two selected hypnotic communication techniques (“pleasant place” or “magic glove”). Rel@x makes use of manuals, cue card reminders, visual aids, videos, and an e-learning platform. To refine Rel@x, a complete training cycle was conducted with seven female pediatric oncology nurses. A mixed method study with an evaluation questionnaire and a post-training focus group interview was conducted. ResultsQuantitative data showed that nurses overall positively rated the training program: relevance and acceptability (median average of 5.4/6); use of hypnotic communication (median average of 5.2/6); expected effects (median average of 5.4/6); program implementation (5.6/6). Two general themes emerged from the qualitative data: perceptions of hypnotic communication and the evaluation of the Rel@x training program. Based on nurses’ suggestions, Rel@x was refined by adding more practical components, more time for practice, more time between the two sessions and additional tools (cue card reminders, keywords, virtual e-learning recap module). Conclusion and clinical implicationsThe use of hypnosis-derived communication during painful procedures and the Rel@x training were viewed favorably amongst pediatric nurses. Rel@x offers a complete training in hypnosis-derived communication for pediatric nurses. This training fosters the optimal use of hypnosis-derived communication during care and may significantly reduce children’s procedural pain and distress

    Monotone Tree-Based GAMI Models by Adapting XGBoost

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    Recent papers have used machine learning architecture to fit low-order functional ANOVA models with main effects and second-order interactions. These GAMI (GAM + Interaction) models are directly interpretable as the functional main effects and interactions can be easily plotted and visualized. Unfortunately, it is not easy to incorporate the monotonicity requirement into the existing GAMI models based on boosted trees, such as EBM (Lou et al. 2013) and GAMI-Lin-T (Hu et al. 2022). This paper considers models of the form f(x)=∑j,kfj,k(xj,xk)f(x)=\sum_{j,k}f_{j,k}(x_j, x_k) and develops monotone tree-based GAMI models, called monotone GAMI-Tree, by adapting the XGBoost algorithm. It is straightforward to fit a monotone model to f(x)f(x) using the options in XGBoost. However, the fitted model is still a black box. We take a different approach: i) use a filtering technique to determine the important interactions, ii) fit a monotone XGBoost algorithm with the selected interactions, and finally iii) parse and purify the results to get a monotone GAMI model. Simulated datasets are used to demonstrate the behaviors of mono-GAMI-Tree and EBM, both of which use piecewise constant fits. Note that the monotonicity requirement is for the full model. Under certain situations, the main effects will also be monotone. But, as seen in the examples, the interactions will not be monotone.Comment: 12 page

    A Review on Relationship Between Human Endogenous Retrovirus Groups and Human Diseases

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    Various factors are involved in the incidence of some diseases like autoimmune, psychiatric and cancerous ones. One of these probable factors is considered as the endogenous retroviruses, for example, proviruses that have been introduced in previous generations in some organisms' genome, and make up over 8% of the human genome. Recent studies have indicated that these factors and their related products (including RNA, cytosolic DNA, and proteins) may affect and also change the host cell function and immune system. This review summarizes the detailed information about the structure, classification, and pathogenesis mechanism of human endogenous retroviruses and their relationship with the autoimmune diseases and some kinds of cancers.

    Development and inter-rater reliability of a tool assessing hypnotic communication behaviours adopted by nurses caring for children with cancer : The Sainte-Justine Hypnotic Communication Assessment Scale

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    Background Several studies in pediatric oncology have shown the successful effects of using hypnotic communication techniques (HCTech) during painful medical procedures. Since no studies assessed the precise use of these techniques with a validated tool, it is unsure that the observed relationships involve the use of HCTech. Objectives To develop a scale evaluating healthcare professionals’ behaviours when using HCTech and to evaluate its inter-rater reliability. Methods This study involved the preliminary steps of the Sainte-Justine Hypnotic Communication Assessment Scale (SJ-HCAS) development process. As part of a larger intervention study, the SJ-HCAS was developed in three steps by five experts and four lay raters using an iterative process applied to subsets of video-recorded nurse-patient interactions. The development aimed to maximize clarity and precision of items as well as minimize redundancy amongst items. Inter-rater reliability was assessed in a randomly selected sample of 1/3 of collected video-recorded interactions (n = 42). Results The final version of the scale is composed of 11 items categorized in two domains pertaining to Relationship and Technique. We found excellent inter-rater reliability for both subscores and total score in two independent inter-rater comparisons (median ICC = 0.879), with most items showing very good to perfect inter-rater reliability (median Kappa = 0.847). Conclusions The results support further work with the SJ-HCAS. The scale has the potential to help ensure the integrity of hypnotic communication training in children which could ultimately promote the dissemination of the practice of HCTech

    GC/MS analysis of the essential oils of Cupressus arizonica Greene, Juniperus communis L. and Mentha longifolia L.

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    ABSTRACT. The chemical composition of the essential oils obtained by hydrodistillation from Cupressus arizonica Greene, Juniperus communis L. and Mentha longifolia L. were determined by gas chromatography-mass spectrometry (GC/MS) analysis. The chemical composition of the essential oils were identified by GC/MS. Eicosane (27.4%), umbellulone (13%) and α-pinene (10.51%) were the major components of C. arizonica oil; sabinene (32%), limonene (26%) and bornyl acetate (7.4%) were the major components of J. communis oil and pulegone (26%), L-menthone (13.4%) and cis-para-menthan-3,8-diol (10.2%) were the major components of M. longifolia oil. The percentage of monoterpenes in the three essential oils was compared. The percentage of monoterpenes in C.arizonica is about 5.2%, J. communis 46%, and M. longifolia is 50.1%. The percentage of terpenes in C. Arizonica (16.3%), J. communis (5.2%) and M. longifolia (9.3%) were reported. But the percentage of cyclic monoterpenes in C. arizonica is about 6%, J. communis 26.1%, and M. longifolia is 3%. Monoterpenes are the most components that make up essential oils.               KEY WORDS: Cupressus arizonica, Juniperus communis, Mentha longifolia, Essential oil, Chemical composition Bull. Chem. Soc. Ethiop. 2019, 33(3), 389-400.DOI: https://dx.doi.org/10.4314/bcse.v33i3.

    Investigation and determination of marine biotoxins in the shellfish of Persian Gulf and Oman Sea

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    Marine algal toxins have drawn worldwide attention because of their involvement in human intoxication and the socio-economic impacts. Marine biotoxins have been produced by harmful bloom algae, known as dinoflagellate. In the present study, two groups of toxins, i.e. PSP, ASP analyzed in the muscle of shellfish caught from the north parts of the Persian Gulf (Bandar Abbas, Bandar Lengeh, Boushehr) and Oman Sea (Chabahar). Sample preparation and extraction were done according to AOAC methods and by ELISA. PSP amounts in the shellfish samples ranged from ND-3.962 and ND-1.477 mg/g muscle. The results showed all samples were safe
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