Search results for: frozen reactions
Commenced in January 2007
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Edition: International
Paper Count: 1140

Search results for: frozen reactions

1050 Hierarchical Zeolites as Catalysts for Cyclohexene Epoxidation Reactions

Authors: Agnieszka Feliczak-Guzik, Paulina Szczyglewska, Izabela Nowak

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A catalyst-assisted oxidation reaction is one of the key reactions exploited by various industries. Their conductivity yields essential compounds and intermediates, such as alcohols, epoxides, aldehydes, ketones, and organic acids. Researchers are devoting more and more attention to developing active and selective materials that find application in many catalytic reactions, such as cyclohexene epoxidation. This reaction yields 1,2-epoxycyclohexane and 1,2-diols as the main products. These compounds are widely used as intermediates in the perfume industry and synthesizing drugs and lubricants. Hence, our research aimed to use hierarchical zeolites modified with transition metal ions, e.g., Nb, V, and Ta, in the epoxidation reaction of cyclohexene using microwaveheating. Hierarchical zeolites are materials with secondary porosity, mainly in the mesoporous range, compared to microporous zeolites. In the course of the research, materials based on two commercial zeolites, with Faujasite (FAU) and Zeolite Socony Mobil-5 (ZSM-5) structures, were synthesized and characterized by various techniques, such as X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and low-temperature nitrogen adsorption/desorption isotherms. The materials obtained were then used in a cyclohexene epoxidation reaction, which was carried out as follows: catalyst (0.02 g), cyclohexene (0.1 cm3), acetonitrile (5 cm3) and dihydrogen peroxide (0.085 cm3) were placed in a suitable glass reaction vessel with a magnetic stirrer inside in a microwave reactor. Reactions were carried out at 45° C for 6 h (samples were taken every 1 h). The reaction mixtures were filtered to separate the liquid products from the solid catalyst and then transferred to 1.5 cm3 vials for chromatographic analysis. The test techniques confirmed the acquisition of additional secondary porosity while preserving the structure of the commercial zeolite (XRD and low-temperature nitrogen adsorption/desorption isotherms). The results of the activity of the hierarchical catalyst modified with niobium in the cyclohexene epoxidation reaction indicate that the conversion of cyclohexene, after 6 h of running the process, is about 70%. As the main product of the reaction, 2-cyclohexanediol was obtained (selectivity > 80%). In addition to the mentioned product, adipic acid, cyclohexanol, cyclohex-2-en-1-one, and 1,2-epoxycyclohexane were also obtained. Furthermore, in a blank test, no cyclohexene conversion was obtained after 6 h of reaction. Acknowledgments The work was carried out within the project “Advanced biocomposites for tomorrow’s economy BIOG-NET,” funded by the Foundation for Polish Science from the European Regional Development Fund (POIR.04.04.00-00-1792/18-00.

Keywords: epoxidation, oxidation reactions, hierarchical zeolites, synthesis

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1049 The Social Reaction to the Wadi Salib Riots (1959) as Reflected in Contemporary Israeli Press

Authors: Ada Yurman

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Social reactions to deviant groups with political goals follow two central patterns; one that associates personal characteristics with deviant behavior, and the other that claims that society is to be blamed for deviant behavior. The establishment usually tends towards the former notion and thus disclaims any responsibility for the distress of the underprivileged, while it is usually those who oppose government policies who believe that the fault lies with society. The purpose of the present research was to examine social reactions to the Wadi Salib riots that occurred in Haifa in 1959. These riots represented the first ethnic protest within Israeli society with its ideology of the ingathering of the exiles. The central question was whether this ideology contributed to the development of a different reaction when compared to reactions to similar events abroad. This question was examined by means of analyzing articles in the Israeli press of that period. The Israeli press representing the views of the establishment was at pains to point out that the rioters were criminals, their object being to obstruct the development of society. Opposition party leaders claimed that the rioters lived in poor circumstances, which constituted a direct result of government policies. An analysis of press reports on the Wadi Salib riots indicates a correspondence between the reaction to these events and similar events abroad. Nevertheless, the reaction to the Wadi Salib riots did not only express a conflict between different political camps, but also different symbolic universes. Each group exploited the events at Wadi Salib to prove that their ideology was the legitimate one.

Keywords: riots, media, political deviance, symbolic universe

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1048 Learners’ Reactions to Writing Activities in an Elementary Algebra Classroom

Authors: Early Sol A. Gadong, Lourdes C. Zamora, Jonny B. Pornel, Aurora Fe C. Bautista

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Various research has shown that writing allows students to engage in metacognition and provides them with a venue to communicate their disposition towards what they are learning. However, few studies have explored students’ feelings about the incorporation of such writing activities in their mathematics classes. Through reflection sheets, group discussions, and interviews, this mixed-methods study explored students’ perceptions and insights on supplementary writing activities in their Elementary Algebra class. Findings revealed that while students generally have a positive regard for writing activities, they have conflicting views about how writing activities can help them in their learning. A big majority contend that writing activities can enhance the learning of mathematical content and attitudes towards mathematics if they allow students to explore and synthesize what they have learned and reflected on their emotional disposition towards mathematics. Also, gender does not appear to play a significant role in students’ reactions to writing activities.

Keywords: writing in math, metacognition, affective factors in learning, elementary algebra classroom

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1047 Military Leadership: Emotion Culture and Emotion Coping in Morally Stressful Situations

Authors: Sofia Nilsson, Alicia Ohlsson, Linda-Marie Lundqvist, Aida Alvinius, Peder Hyllengren, Gerry Larsson

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In irregular warfare contexts, military personnel are often presented with morally ambiguous situations where they are aware of the morally correct choice but may feel prevented to follow through with it due to organizational demands. Moral stress and/or injury can be the outcome of the individual’s experienced dissonance. These types of challenges put a large demand on the individual to manage their own emotions and the emotions of others, particularly in the case of a leader. Both the ability and inability for emotional regulation can result in different combinations of short and long term reactions after morally stressful events, which can be either positive or negative. Our study analyzed the combination of these reactions based upon the types of morally challenging events that were described by the subjects. 1)What institutionalized norms concerning emotion regulation are favorable in short-and long-term perspectives after a morally stressful event? 2)What individual emotion-focused coping strategies are favorable in short-and long-perspectives after a morally stressful? To address these questions, we conducted a quantitative study in military contexts in Sweden and Norway on upcoming or current military officers (n=331). We tested a theoretical model built upon a recently developed qualitative study. The data was analyzed using factor analysis, multiple regression analysis and subgroup analyses. The results indicated that an individual’s restriction of emotion in order to achieve an organizational goal, which results in emotional dissonance, can be an effective short term strategy for both the individual and the organization; however, it appears to be unfavorable in a long-term perspective which can result in negative reactions. Our results are intriguing because they showed an increased percentage of reported negative long term reactions (13%), which indicated PTSD-related symptoms in comparison to previous Swedish studies which indicated lower PTSD symptomology.

Keywords: emotion culture, emotion coping, emotion management, military

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1046 Exploring Time-Series Phosphoproteomic Datasets in the Context of Network Models

Authors: Sandeep Kaur, Jenny Vuong, Marcel Julliard, Sean O'Donoghue

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Time-series data are useful for modelling as they can enable model-evaluation. However, when reconstructing models from phosphoproteomic data, often non-exact methods are utilised, as the knowledge regarding the network structure, such as, which kinases and phosphatases lead to the observed phosphorylation state, is incomplete. Thus, such reactions are often hypothesised, which gives rise to uncertainty. Here, we propose a framework, implemented via a web-based tool (as an extension to Minardo), which given time-series phosphoproteomic datasets, can generate κ models. The incompleteness and uncertainty in the generated model and reactions are clearly presented to the user via the visual method. Furthermore, we demonstrate, via a toy EGF signalling model, the use of algorithmic verification to verify κ models. Manually formulated requirements were evaluated with regards to the model, leading to the highlighting of the nodes causing unsatisfiability (i.e. error causing nodes). We aim to integrate such methods into our web-based tool and demonstrate how the identified erroneous nodes can be presented to the user via the visual method. Thus, in this research we present a framework, to enable a user to explore phosphorylation proteomic time-series data in the context of models. The observer can visualise which reactions in the model are highly uncertain, and which nodes cause incorrect simulation outputs. A tool such as this enables an end-user to determine the empirical analysis to perform, to reduce uncertainty in the presented model - thus enabling a better understanding of the underlying system.

Keywords: κ-models, model verification, time-series phosphoproteomic datasets, uncertainty and error visualisation

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1045 Green Synthesis of Nicotine Analogues via Cycloaddition Reactions

Authors: Agnieszka Fryźlewicz, Jowita Kras, Mikołaj Sadowski, Agnieszka Łapczuk-Krygier, Agnieszka Kącka-Zych Radomir Jasiński

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Nicotines are a group of compounds containing conjugated pyridine and pyrrolidine molecular segments. They are widely applied in medicine, pharmacy, and agriculture. Namely as researched treatment of Alzheimer, depression, Parkinson's, Tourette syndrome, general nervous and mental disorders. Furthermore, nicotine itself is used as a stimulant, animal repellent and was widely applied as an insecticide. In our work, we obtained nicotine analogues with possible applications in agriculture. The synthesis employed [3+2] cycloaddition (32CA) reactions, occurring between pirydyl-functionalised nitrones and conjugated nitroalkenes, that allowed us to fully regio- and stereoselectively obtain product. Moreover, cycloaddition reaction realizes rapidly in mild conditions with the full atomic economy, thus fitting into “green chemistry” trends.

Keywords: nicotine, isoxazolidine, 1-3-dipolar cycloaddition, green chemistry, biological and pharmacological activity

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1044 Bodybuilding, Gender and Age: A Qualitative Exploration of the Perspectives of Older Canadian Females

Authors: Amy Matharu

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Existing literature on older athletes in competitive sports is often male-dominated and limited. This study explores how age and gender impact the experiences of older female bodybuilders in Canada using the social theories of deviance and intersectionality. Qualitative, semi-structured interviews were conducted with 11 Canadian female bodybuilders over the age of 45. Interviews were transcribed, coded, and thematically analysed. This study was approached from a phenomenological perspective. The participants deviated from their perceived social norms of women their age. They exhibited deviance with their actions, such as prioritising themselves and following extreme dieting practices, and with their aesthetics, such as maintaining a muscular appearance. Participants received both positive and negative reactions from society resulting in both admiration and stigmatisation. These reactions varied based on the environment, audience, and context of the situation. Overall, the intersection of age and gender results in a unique position for older female bodybuilders within society and within the sport.

Keywords: age, bodybuilding, gender, females

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1043 Manifestation of Behavioral and Emotional Disturbances and Perceived Coping Strategies of Earthquake Survived Children

Authors: Mahwish Rabia, Najma Najam

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The present study was conducted to identify emotional and behavioral disturbances among earthquake survived children and the perceived coping strategies of affected children. In the present study, a sample of 50 children (6-16 years) belonging to badly affected areas (earthquake) was selected from different camps in Islamabad. Child Behavioral Checklist (CBCL) and Rotter Incomplete Sentence Blank (RISB) interpretations were used to assess variety of emotional and behavioral patterns, and Child Coping Strategies Checklist (CCSC) was used to assess the perceived coping strategies of affected children. Results showed that some of the frequent emotional/behavioral reactions exhibited by children like withdrawal, anxiety\depression, aggression and attention seeking behavior. Whereas gender-based comparisons indicated that female children showed more internalizing behavioral patterns (withdrawn, somatic complaints) as compared to male children who exhibited more externalizing emotions (aggression, delinquent behavior).Coping strategies in which male children tried to adopt Positive Cognitive Restructuring and for distracting attention they used distraction strategies of coping. It is concluded that significant negative emotional and behavioral reactions are exhibited by the earthquake affected children. Male children adopt coping strategies more as compared to female children. The study identifies the negative emotional and behavioral reactions towards trauma, which can be helpful for identifying the problematic area for counseling and therapeutic interventions for these children.

Keywords: behavioural disturbances, emotional disturbances, coping strategies, earthquake, children

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1042 Evaluation of the Effect of Lactose Derived Monosaccharide on Galactooligosaccharides Production by β-Galactosidase

Authors: Yenny Paola Morales Cortés, Fabián Rico Rodríguez, Juan Carlos Serrato Bermúdez, Carlos Arturo Martínez Riascos

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Numerous benefits of galactooligosaccharides (GOS) as prebiotics have motivated the study of enzymatic processes for their production. These processes have special complexities due to several factors that make difficult high productivity, such as enzyme type, reaction medium pH, substrate concentrations and presence of inhibitors, among others. In the present work the production of galactooligosaccharides (with different degrees of polymerization: two, three and four) from lactose was studied. The study considers the formulation of a mathematical model that predicts the production of GOS from lactose using the enzyme β-galactosidase. The effect of pH in the reaction was studied. For that, phosphate buffer was used and with this was evaluated three pH values (6.0.6.5 and 7.0). Thus it was observed that at pH 6.0 the enzymatic activity insignificant. On the other hand, at pH 7.0 the enzymatic activity was approximately 27 times greater than at 6.5. The last result differs from previously reported results. Therefore, pH 7.0 was chosen as working pH. Additionally, the enzyme concentration was analyzed, which allowed observing that the effect of the concentration depends on the pH and the concentration was set for the following studies in 0.272 mM. Afterwards, experiments were performed varying the lactose concentration to evaluate its effects on the process and to generate the data for the adjustment of the mathematical model parameters. The mathematical model considers the reactions of lactose hydrolysis and transgalactosylation for the production of disaccharides and trisaccharides, with their inverse reactions. The production of tetrasaccharides was negligible and, because of that, it was not included in the model. The reaction was monitored by HPLC and for the quantitative analysis of the experimental data the Matlab programming language was used, including solvers for differential equations systems integration (ode15s) and nonlinear problems optimization (fminunc). The results confirm that the transgalactosylation and hydrolysis reactions are reversible, additionally inhibition by glucose and galactose is observed on the production of GOS. In relation to the production process of galactooligosaccharides, the results show that it is necessary to have high initial concentrations of lactose considering that favors the transgalactosylation reaction, while low concentrations favor hydrolysis reactions.

Keywords: β-galactosidase, galactooligosaccharides, inhibition, lactose, Matlab, modeling

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1041 Immobilization of β-Galactosidase from Kluyveromyces Lactis on Polyethylenimine-Agarose for Production of Lactulose

Authors: Carlos A. C. G. Neto, Natan C. G. Silva, Thais O. Costa, Luciana R. B. Goncalves, Maria v. P. Rocha

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Galactosidases are enzymes responsible for catalyzing lactose hydrolysis reactions and also favoring transgalactosylation reactions for the production of prebiotics, among which lactulose stands out. These enzymes, when immobilized, can have some enzymatic characteristics substantially improved, and the coating of supports with multifunctional polymers in immobilization processes is a promising alternative in order to extend the useful life of the biocatalysts, for example, the coating with polyethyleneimine (PEI). PEI is a flexible polymer that suits the structure of the enzyme, giving greater stability, especially for multimeric enzymes such as β-galactosidases and also protects it from environmental variations, for example, pH and temperature. In addition, it can substantially improve the immobilization parameters and also the efficiency of enzymatic reactions. In this context, the aim of the present work was first to develop biocatalysts of β-galactosidase from Kluyveromyces lactis immobilized on PEI coated agarose, determining the immobilization parameters, its operational and thermal stability, and then to apply it in the hydrolysis of lactose and synthesis of lactulose, using whey as a substrate. This immobilization strategy was chosen in order to improve the catalytic efficiency of the enzyme in the transgalactosylation reaction for the production of prebiotics, and there are few studies with β-galactosidase from this strain. The immobilization of β-galactosidase in agarose previously functionalized with 48% (w/v) glycidol and then coated with 10% (w/v) PEI solution was evaluated using an enzymatic load of 10 mg/g of protein. Subsequently, the hydrolysis and transgalactosylation reactions were conducted at 50 °C, 120 RPM for 20 minutes, using whey (66.7 g/L of lactose) supplemented with 133.3 g/L fructose at a ratio of 1:2 (lactose/fructose). Operational stability studies were performed in the same conditions for 10 cycles. Thermal stabilities of biocatalysts were conducted at 50 ºC in 50 mM phosphate buffer, pH 6.6, with 0.1 mM MnCl2. The biocatalysts whose supports were coated were named AGA_GLY_PEI_GAL, and those that were not coated were named AGA_GLY_GAL. The coating of the support with PEI considerably improved immobilization yield (2.6-fold), the biocatalyst activity (1.4-fold), and efficiency (2.2-fold). The biocatalyst AGA_GLY_PEI_GAL was better than AGA_GLY_GAL in hydrolysis and transgalactosylation reactions, converting 88.92% of lactose at 5 min of reaction and obtaining a residual concentration of 5.24 g/L. Besides that, it was produced 13.90 g/L lactulose in the same time interval. AGA_GLY_PEI_GAL biocatalyst was stable during the 10 cycles evaluated, converting approximately 80% of lactose and producing 10.95 g/L of lactulose even after the tenth cycle. However, the thermal stability of AGA_GLY_GAL biocatalyst was superior, with a half-life time 5 times higher, probably because the enzyme was immobilized by covalent bonding, which is stronger than adsorption (AGA_GLY_PEI_GAL). Therefore, the strategy of coating the supports with PEI has proven to be effective for the immobilization of β-galactosidase from K. lactis, considerably improving the immobilization parameters, as well as the enzyme, catalyzed reactions. In addition, the use of whey as a raw material for lactulose production has proved to be an industrially advantageous alternative.

Keywords: β-galactosidase, immobilization, lactulose, polyethylenimine, whey

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1040 Calcined Tertiaries Hydrotalcites as Supports of Cobalt-Molybdenum Based Catalysts for the Hydrodesulfurization Reaction of Dibenzothiophene

Authors: Edwin Oviedo, Carlos Linares, Philippe Ayrault, Sylvette Brunet

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Nowadays, light conventional crude oils are going down. Therefore, the exploitation of heavy crude oils has been increasing. Hence, a major quantity of refractory sulfur compounds such as dibenzothiophene (DBT) should be removed. Many efforts have been carried out to modify hydrotreatment typical supports in order to increase hydrodesulfurization (HDS) reactions. The present work shows the synthesis of tertiaries MgFeAl(0.16), MgFeAl(0.32), CoFeAl, ZnFeAl hydrotalcites, as supports of CoMo based catalysts, where 0.16 and 0.32 are the Fe3+/Al3+ molar ratio. Solids were characterized by different techniques (XRD, CO2-TPD, H2-TPR, FT-IR, BET, Chemical Analysis and HRTEM) and tested in the DBT HDS reaction. The reactions conditions were: Temp=325°C, P=40 Bar, H2/feed=475. Results show that the catalysts CoMo/MgFeAl(0.16) and CoMo/MgFeAl(0.32), which were the most basics, reduced the sulfur content from 500ppm to less than 1 ppm, increasing the cyclohexylbenzene content, i.e. presented a higher selective toward the HYD pathway than reference catalyst CoMo/γ- Al2O3. This is suitable for improving the fuel quality due to the increase of the cetane number. These catalysts were also more active to the HDS reaction increasing the direct desulfurization (DDS) way and presented a good stability. It is advantageous when the gas oil centane number should be improved. Cobalt, iron or zinc species inside support could avoid the Co and Mo dispersion or form spinel species which could be less active to hydrodesulfuration reactions, while hydrotalcites containing Mg increases the HDS activity probably due to improved Co/Mo ratio.

Keywords: catalyst, cetane number, dibenzothiophene, diesel, hydrodesulfurization, hydrotreatment, MoS2

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1039 Portfolio Restructuring of Banks: The Impact on Performance and Risk

Authors: Hannes Koester

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Driven by difficult market conditions and increasing regulations, many banks are making the strategic decision to restructure their portfolio by divesting several business segments. Using a unique dataset of 727 portfolio restructuring announcements by 161 international listed banks over the period 1999 to 2015, we investigate the impact of restructuring measurements on the stock performance as well as on the banks’ profitability and risk. Employing the event study methodology, we detect positive stock market reactions on the announcement of restructuring measurements. These positive stock market reactions indicate that shareholders reward banks’ specialization activities. However, the results of the system GMM regressions show a negative relation between restructuring measurements and banks’ return on assets and a positive relation towards the individual and systemic risk of banks. These empirical results indicate that there is no guarantee that portfolio restructurings will result in a more profitable and less risky institution.

Keywords: bank performance, bank risk, divestiture, restructuring, systemic risk

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1038 Serosurveillance of Measles Virus amongst Vaccinated Children of a Rural Population of Sindh

Authors: Zeb Hussain, Muhammad Asif Qureshi, Shaheen Sharafat

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Background: Measles is a contagious viral infection common in childhood. Vaccination against measles is included in the expanded program of immunization (EPI). However, and alarmingly, a high mortality rate is observed due to measles infection in Pakistan. Moreover a recent outbreak of measles in various areas of Pakistan further highlights the problem. It is therefore important to investigate measles specific IgG (antibody) levels in our population. Objective: To quantify measles specific IgG antibodies amongst vaccinated children in district Qamber Shahdadkot, Sindh. Methodology: This cross-sectional study was conducted at the Microbiology section of the Dow-Diagnostic-Research-and-Reference-Laboratory (DDRRL), DUHS after Institutional Review Board approval (IRB-516/DUHS/-14) during August-December-2014. A total of 173 participants (residents of district Qamber Shahdadkot, Sindh) aged between 1-5 years were recruited in the study. Blood samples were collected as per standard phlebotomy guidelines. Blood was stored at 4 °C overnight. Samples were subsequently spun at a speed of 10000rpm to separate sera, which were divided into small aliquots to be frozen at -20 °C. Frozen sera were transported to the DDRRL on dry ice. Measles specific IgG (antibody) titers were quantified using enzyme linked immunosorbant assay (ELISA). Results: Blood was collected from a total of 173 individuals ranging between 1-5 years of age. Of these, a total of 88 participants were males and 85 were females. Of the 173 investigated samples, only 53 (30.6%) showed protective IgG titers against measles while 120 (69%) were sero-negative. Measles specific IgG antibodies titers were higher in female participants compared to the males. Conclusion: Our data demonstrate that a substantial percentage of vaccinated children in district Qamber-Shahdadkot did not have protective antibody titres against measles. It is therefore extremely important to investigate measles specific IgG levels in various parts of Pakistan in order to implement appropriate protective measures.

Keywords: sero-surveillance, measles, vaccinated children, Pakistan

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1037 The Preparation of 2H-Indazolo [2, 1-b] Phthalazinetriones by One-Pot 4,4ʹ-Bipyridinium Dichloride Ordered Mesoporous Silica

Authors: Aigin Bashti

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Preparation of multicomponent reactions (MCRs) via a simple one-pot strategy is considered a novel procedure which has attracted a lot of interest from organic and medicinal chemists. Due to the great importance of phthalazide triones, it was decided to introduce a novel and cost-effective green procedure for the preparation of these derivatives. In this methodology, an efficient 4,4ʹ-Bipyridinium Dichloride Ordered Mesoporous Silica functionalized catalyst (BP-SBA-15) was utilized. The catalyst was characterized by X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermo-gravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FT-IR) analysis. In conclusion, it should be mentioned that this methodology has some advantages, including short reaction time, high yield of the products, recyclable catalyst, green procedure, and facile work-up procedure. The catalyst was successfully utilized for the one-pot preparation of various phthalazinetrione derivatives.

Keywords: dimedone, green procedure, multicomponent reactions, phthalhydrazide

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1036 Clinical and Chemokine Profile in Leprosy Patients During Multidrug Therapy (MDT) and Their Healthy Contacts: A Randomized Control Trial

Authors: Rohit Kothari

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Background: Leprosyis a chronic granulomatous diseasecaused by Mycobacterium leprae (M. Lepra). Reactions may interrupt its usual chronic course.Type-1 (T1R)and type-2 lepra reaction(T2R) are acute events and signifytype-IV and type-III hypersensitivity responses, respectively. Various chemokines like CCL3, 5, 11, and CCL24 may be increased during the course of leprosy or during reactions and may serve as markers of early diagnosis, response to therapy, and prognosis. Objective: To find correlation of CCL3, 5, 11, and CCL24 in leprosy patients on multidrug therapy and their family contacts after ruling out active disease during leprosy treatment and during periods of lepra reactions. Methodology: This randomized control trial was conducted in 50 clinico-histopathologically diagnosed cases of leprosy in a tertiary care hospital in Bengaluru, India. 50 of their family contacts were adequately examined and investigated should the need be to rule out active disease. The two study-groups comprised of leprosy cases, and the age, sex, and area of residence matched healthy contactswho were given single-dose rifampicin prophylaxis, respectively. Blood samples were taken at baseline, six months, and after one yearin both the groups (on completion of MDT in leprosy cases)and also during periods of reaction if occurred in leprosy cases. Results: Our study found that at baseline, CCL5, 11, and 24 were higher in leprosy cases as compared to the healthy contacts, and the difference was statistically significant.CCL3 was also found to be higherat baseline in leprosy cases, however, the difference was not statistically significant. At six months and one year, the levels of CCL 5, 11, and 24 reduced, and the difference was statistically significant in leprosy cases, whereas it remained almost static in all the healthy contacts. Twenty patients of leprosy developed lepra reaction during the course of one year, and during reaction, the increase in CCL11 and 24 was statistically significant from baseline, whereas CCL3 and 5 did not rise significantly. One of the healthy contacts developed signs of leprosy in the form of hypopigmented numb patch and was clinico-histopathologically, and CCL11 and 24 were found to be higher with a statistically significant difference from the baseline values. Conclusion: CCL5, 11, and 24 are sensitive markers of diagnosing leprosy, response to MDT, and prognosis and are not increased in healthy contacts. CCL11 and 24 are sensitive markers of lepra reactions and may serve as one of the early diagnostic modalities for identifying lepra reaction and also leprosy in healthy contacts. To the best of our knowledge, this is the first study to evaluate these biomarkers in leprosy cases and their healthy contacts with a follow-up of upto one year with one of them developing the disease, and the same was confirmed based on these biomarkers as well.

Keywords: chemokine profile, healthy contacts, leprosy, lepra reactions

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1035 Epidemiological and Clinical Study of Childhood Hansens in a Tertiary Care Hospital

Authors: M. Shahana

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Introduction: Leprosy (Hansens) is one of the major health problems in the developing countries. Sixty percent of the world leprosy cases are in India. According to the 2006 census India has about 54% of the total new cases detected globally. The National Leprosy Elimination Programme in 2012 has reported 9.7% of childhood leprosy. There are only few studies related to paediatric leprosy. Aim: To study the epidemiology and various clinical presentations of leprosy in the paediatric age group. Material and Methods: A 4-year prospective study was done in the out-patient department of dermatology in a tertiary care hospital. All the patients were screened for leprosy and children with a confirmed diagnosis of leprosy were taken up for the study. Results: Total of 321 cases of Hansens were recorded during this period out of which 41 were children. The male to female ratio was 2.72:1. A positive family history was found in 18%. Most of them presented with single hypopigmented hypoanesthetic patch. Conclusions: Children presented with more of Borderline tuberculoid type and reactions or deformities were less common.

Keywords: Hansens, hypoaneasthetic patch, leprosy, reactions

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1034 Direct Palladium-Catalyzed Selective N-Allylation of 2,3-Disubstituted Indoles with Allylic Alcohols in Water

Authors: Bai-Jing Peng, Shyh-Chyun Yang

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Organic reactions in water have recently attracted much attention, not only because unique reactivity is often observed in water but also because water is a safe and economical substitute for conventional organic solvents. Thus, development of environmental safe, atom-economical reactions in water is one of the most important goals of synthetic chemistry. The recent paper has documented renewed interest in the use of allylic substrates in the synthesis of new C−C, C−N, and C−O bonds. We have reported our attempts and some successful applications of a process involving the C-O bond cleavage catalyzed by palladium or platinum complexes in water. Because of the importance of heterocycle indole derivatives, much effort has been directed toward the development of methods for functionalization of the indole nucleus at N1 site. In our research, the palladium-catalyzed 2,3-disubstitued indoles with allylic alcohols was investigated under different conditions. Herein, we will establish a simple, convenient, and efficient method, which affords high yields of allylated indoles.

Keywords: palladium-catalyzed, allylic alcohols, indoles, water, allylation

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1033 Analyses of Adverse Drug Reactions Reported of Hospital in Taiwan

Authors: Yu-Hong Lin

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Background: An adverse drug reaction (ADR) reported is an injury which caused by taking medicines. Sometimes the severity of ADR reported may be minor, but sometimes it could be a life-threatening situation. In order to provide healthcare professionals as a better reference in clinical practice, we do data collection and analysis from our hospital. Methods: This was a retrospective study of ADRs reported performed from 2014 to 2015 in our hospital in Taiwan. We collected assessment items of ADRs reported, which contain gender and age, occurring sources, Anatomical Therapeutic Chemical (ATC) classification of suspected drugs, types of adverse reactions, Naranjo score calculating by Naranjo Adverse Drug Reaction Probability Scale and so on. Results: The investigation included two hundred and seven ADRs reported. Most of ADRs reported were occurring in outpatient department (92%). The average age of ADRs reported was 65.3 years. Less than 65 years of age were in the majority in this study (54%). Majority of all ADRs reported were males (51%). According to ATC classification system, the major classification of suspected drugs was cardiovascular system (19%) and antiinfectives for systemic use (18%) respectively. Among the adverse reactions, Dermatologic Effects (35%) were the major type of ADRs. Also, the major Naranjo scores of all ADRs reported ranged from 1 to 4 points (91%), which represents a possible correlation between ADRs reported and suspected drugs. Conclusions: Definitely, ADRs reported is still an extremely important information for healthcare professionals. For that reason, we put all information of ADRs reported into our hospital's computer system, and it will improve the safety of medication use. By hospital's computer system, it can remind prescribers to think of information about patient's ADRs reported. No drugs are administered without risk. Therefore, all healthcare professionals should have a responsibility to their patients, who themselves are becoming more aware of problems associated with drug therapy.

Keywords: adverse drug reaction, Taiwan, healthcare professionals, safe use of medicines

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1032 Patients Reactions to Medical Errors in Hospitals: The Need for Social Workers in Nigeria

Authors: Emmanuel Temitope Adaranijo

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Medical error is on the increase in many nations and like many developing nations, Nigeria is not excluded and more importantly, Lafia, Nasarawa state, where the study was carried. The study was undertaken to explore Patients' knowledge and their reactions to medical errors in hospitals in Lafia Local Government Area; therefore, five objectives were formulated to guide the study. The survey research design was employed and triangulation of quantitative and qualitative instruments was used to collect data. The total population for the study was 330,712 and the sample size was 400; however, only 343 patients and three doctors responded to the quantitative and qualitative study, respectively. Frequency distribution, simple percentage, and r test were used to analyze the data obtained from respondents. The findings revealed that medical errors are prevalent in hospitals in Lafia and the patients are neither aware nor willing to report such occurrence. The study recommends that social workers, hospital management, and governments should take up their roles in reducing the occurrence of medical errors.

Keywords: health, hospital, medical errors, social work

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1031 Earnings-Related Information, Cognitive Bias, and the Disposition Effect

Authors: Chih-Hsiang Chang, Pei-Shan Kao

Abstract:

This paper discusses the reaction of investors in the Taiwan stock market to the most probable unknown earnings-related information and the most probable known earnings-related information. As compared with the previous literature regarding the effect of an official announcement of earnings forecast revision, this paper further analyzes investors’ cognitive bias toward the unknown and known earnings-related information, and the role of media during the investors' reactions to the foresaid information shocks. The empirical results show that both the unknown and known earnings-related information provides useful information content for a stock market. In addition, cognitive bias and disposition effect are the behavioral pitfalls that commonly occur in the process of the investors' reactions to the earnings-related information. Finally, media coverage has a remarkable influence upon the investors' trading decisions.

Keywords: cognitive bias, role of media, disposition effect, earnings-related information, behavioral pitfall

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1030 Isolation and Culture of Keratinocytes and Fibroblasts to Develop Artificial Skin Equivalent in Cats

Authors: Lavrentiadou S. N., Angelou V., Chatzimisios K., Papazoglou L.

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The aim of this study was the isolation and culture of keratinocytes and fibroblasts from feline skin to ultimately create an artificial engineered skin (including dermis and epidermis) useful for the effective treatment of large cutaneous deficits in cats. Epidermal keratinocytes and dermal fibroblasts were freshly isolated from skin biopsies using an 8 mm biopsy punch obtained from 8 healthy cats that had undergone ovariohysterectomy. The owner’s consent was obtained. All cats had a complete blood count and a serum biochemical analysis and were screened for feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) preoperatively. The samples were cut into small pieces and incubated with collagenase (2 mg/ml) for 5-6 hours. Following digestion, cutaneous cells were filtered through a 100 μm cell strainer, washed with DMEM, and grown in DMEM supplemented with 10% FBS. The undigested epidermis was washed with DMEM and incubated with 0.05% Trypsin/0.02% EDTA (TE) solution. Keratinocytes recovered in the TE solution were filtered through a 100 μm and a 40 μm cell strainer and, following washing, were grown on a collagen type I matrix in DMEM: F12 (3:1) medium supplemented with 10% FΒS, 1 μm hydrocortisone, 1 μm isoproterenol and 0.1 μm insulin. Both fibroblasts and keratinocytes were grown in a humidified atmosphere with 5% CO2 at 37oC. The medium was changed twice a week and cells were cultured up to passage 4. Cells were grown to 70-85% confluency, at which point they were trypsinized and subcultured in a 1:4 dilution. The majority of the cells in each passage were transferred to a freezing medium and stored at -80oC. Fibroblasts were frozen in DMEM supplemented with 30% FBS and 10% DMSO, whereas keratinocytes were frozen in a complete keratinocyte growth medium supplemented with 10% DMSO. Both cell types were thawed and successfully grown as described above. Therefore, we can create a bank of fibroblasts and keratinocytes, from which we can recover cells for further culture and use for the generation of skin equivalent in vitro. In conclusion, cutaneous cell isolation and cell culture and expansion were successfully developed. To the authors’ best knowledge, this is the first study reporting isolation and culture of keratinocytes and fibroblasts from feline skin. However, these are preliminary results and thus, the development of autologous-engineered feline skin is still in process.

Keywords: cat, fibroblasts, keratinocytes, skin equivalent, wound

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1029 Synthesis, Characterization and Catecholase Study of Novel Bidentate Schiff Base Derived from Dehydroacetic Acid

Authors: Salima Tabti, Chaima Maouche, Tinhinene Louaileche, Amel Djedouani, Ismail Warad

Abstract:

Novel Schiff base ligand HL has been synthesized by condensation of aromatic amine and DHA. It was characterized by UV-Vis, FT-IR, SM, NMR (1H, 13C) and also by single-crystal X-ray diffraction. The crystal structure shows that compound crystallized in a triclinic system in P-1 space group and with a two unit per cell (Z = 2).The asymmetric unit, contains one independent molecules, the conformation is determined by an intermolecular N-H…O hydrogen bond with an S(6) ring motif. The molecule have an (E) conformation about the C=N bond. The dihedral angles between the phenyl and pyran ring planes is 89.37 (1), the two plans are approximately perpendicular. The catecholase activity of is situ copper complexes of this ligand has been investigated against catechol. The progress of the oxidation reactions was closely monitored over time following the strong peak of catechol using UV-Vis. Oxidation rates were determined from the initial slope of absorbance. time plots, then analyzed by Michaelis-Menten equations. Catechol oxidation reactions were realized using different concentrations of copper acetate and ligand (L/Cu: 1/1, 1/2, 2/1). The results show that all complexes were able to catalyze the oxidation of catechol. Acetate complexes have the highest activity. Catalysis is a branch of chemical kinetics that, more generally, studies the influence of all physical or chemical factors determining reaction rates. It solves a lot of problems in the chemistry reaction process, especially for a green, economic and less polluting chemistry. For this reason, the search for new catalysts for known organic reactions, occupies a very advanced place in the themes proposed by the chemists.

Keywords: dehydroacetic acid, catechol, copper, catecholase activity, x-ray

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1028 OPEN-EmoRec-II-A Multimodal Corpus of Human-Computer Interaction

Authors: Stefanie Rukavina, Sascha Gruss, Steffen Walter, Holger Hoffmann, Harald C. Traue

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OPEN-EmoRecII is an open multimodal corpus with experimentally induced emotions. In the first half of the experiment, emotions were induced with standardized picture material and in the second half during a human-computer interaction (HCI), realized with a wizard-of-oz design. The induced emotions are based on the dimensional theory of emotions (valence, arousal and dominance). These emotional sequences - recorded with multimodal data (mimic reactions, speech, audio and physiological reactions) during a naturalistic-like HCI-environment one can improve classification methods on a multimodal level. This database is the result of an HCI-experiment, for which 30 subjects in total agreed to a publication of their data including the video material for research purposes. The now available open corpus contains sensory signal of: video, audio, physiology (SCL, respiration, BVP, EMG Corrugator supercilii, EMG Zygomaticus Major) and mimic annotations.

Keywords: open multimodal emotion corpus, annotated labels, intelligent interaction

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1027 Construction and Application of Zr-MCM41 Nanoreactors as Highly Active and Efficiently Catalyst in the Synthesis of Biginelli-Type Compounds

Authors: Zohreh Derikvand

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Nanoreactors Zr-MCM-41were prepared via the reaction of ZrOCl2, Fumed silica, sodium hydroxide and cethyltrimethyl ammonium bromide under hydrothermal condition. The prepared nanoreactors were characterized by FT-IR spectroscopy, X-ray diffraction (XRD), Scanning electron micrographs (SEM) and nitrogen adsorption-desorption. The XRD pattern of Zr-MCM-41 exhibits a high-intensity (100) and two low-intensity reflections (110 and 200) which are characteristic of hexagonal structure, exhibiting the long-range order and good textural uniformity of mesoporous structure. Based on the green chemistry approach, we report an efficient and environmentally benign protocol to study the catalytic activity of Zr-MCM-41 in the Biginelli type reactions initially. Nanoreactors Zr-MCM-41 were used as highly recoverable and reusable catalyst for synthesis of 3,4-dihydropyrimidin-2(1H)-one, octahydroquinazolinone, benzimidazolo-quinazolineone and 4,6-diarylpyrimidin-2(1H)-one. The methodology offers several advantages such as short reaction time, high yields and simple operation. The catalyst was active up to three cycles.

Keywords: Zr-MCM-41 nanoreactors, Biginelli like reactions, 3, 4-dihydropyrimidin-2(1H)-ones, ctahydroquinazolinones

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1026 A Rationale to Describe Ambident Reactivity

Authors: David Ryan, Martin Breugst, Turlough Downes, Peter A. Byrne, Gerard P. McGlacken

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An ambident nucleophile is a nucleophile that possesses two or more distinct nucleophilic sites that are linked through resonance and are effectively “in competition” for reaction with an electrophile. Examples include enolates, pyridone anions, and nitrite anions, among many others. Reactions of ambident nucleophiles and electrophiles are extremely prevalent at all levels of organic synthesis. The principle of hard and soft acids and bases (the “HSAB principle”) is most commonly cited in the explanation of selectivities in such reactions. Although this rationale is pervasive in any discussion on ambident reactivity, the HSAB principle has received considerable criticism. As a result, the principle’s supplantation has become an area of active interest in recent years. This project focuses on developing a model for rationalizing ambident reactivity. Presented here is an approach that incorporates computational calculations and experimental kinetic data to construct Gibbs energy profile diagrams. The preferred site of alkylation of nitrite anion with a range of ‘hard’ and ‘soft’ alkylating agents was established by ¹H NMR spectroscopy. Pseudo-first-order rate constants were measured directly by ¹H NMR reaction monitoring, and the corresponding second-order constants and Gibbs energies of activation were derived. These, in combination with computationally derived standard Gibbs energies of reaction, were sufficient to construct Gibbs energy wells. By representing the ambident system as a series of overlapping Gibbs energy wells, a more intuitive picture of ambident reactivity emerges. Here, previously unexplained switches in reactivity in reactions involving closely related electrophiles are elucidated.

Keywords: ambident, Gibbs, nucleophile, rates

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1025 High-Pressure Polymorphism of 4,4-Bipyridine Hydrobromide

Authors: Michalina Aniola, Andrzej Katrusiak

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4,4-Bipyridine is an important compound often used in chemical practice and more recently frequently applied for designing new metal organic framework (MoFs). Here we present a systematic high-pressure study of its hydrobromide salt. 4,4-Bipyridine hydrobromide monohydrate, 44biPyHBrH₂O, at ambient-pressure is orthorhombic, space group P212121 (phase a). Its hydrostatic compression shows that it is stable to 1.32 GPa at least. However, the recrystallization above 0.55 GPa reveals a new hidden b-phase (monoclinic, P21/c). Moreover, when the 44biPyHBrH2O is heated to high temperature the chemical reactions of this compound in methanol solution can be observed. High-pressure experiments were performed using a Merrill-Bassett diamond-anvil cell (DAC), modified by mounting the anvils directly on the steel supports, and X-ray diffraction measurements were carried out on a KUMA and Excalibur diffractometer equipped with an EOS CCD detector. At elevated pressure, the crystal of 44biPyHBrH₂O exhibits several striking and unexpected features. No signs of instability of phase a were detected to 1.32 GPa, while phase b becomes stable at above 0.55 GPa, as evidenced by its recrystallizations. Phases a and b of 44biPyHBrH2O are partly isostructural: their unit-cell dimensions and the arrangement of ions and water molecules are similar. In phase b the HOH-Br- chains double the frequency of their zigzag motifs, compared to phase a, and the 44biPyH+ cations change their conformation. Like in all monosalts of 44biPy determined so far, in phase a the pyridine rings are twisted by about 30 degrees about bond C4-C4 and in phase b they assume energy-unfavorable planar conformation. Another unusual feature of 44biPyHBrH2O is that all unit-cell parameters become longer on the transition from phase a to phase b. Thus the volume drop on the transition to high-pressure phase b totally depends on the shear strain of the lattice. Higher temperature triggers chemical reactions of 44biPyHBrH2O with methanol. When the saturated methanol solution compound precipitated at 0.1 GPa and temperature of 423 K was required to dissolve all the sample, the subsequent slow recrystallization at isochoric conditions resulted in disalt 4,4-bipyridinium dibromide. For the 44biPyHBrH2O sample sealed in the DAC at 0.35 GPa, then dissolved at isochoric conditions at 473 K and recrystallized by slow controlled cooling, a reaction of N,N-dimethylation took place. It is characteristic that in both high-pressure reactions of 44biPyHBrH₂O the unsolvated disalt products were formed and that free base 44biPy and H₂O remained in the solution. The observed reactions indicate that high pressure destabilized ambient-pressure salts and favors new products. Further studies on pressure-induced reactions are carried out in order to better understand the structural preferences induced by pressure.

Keywords: conformation, high-pressure, negative area compressibility, polymorphism

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1024 Sonochemical Zinc Oxide and Layered Hydroxy Zinc Acetate Synthesis in Fenton-Like Reactions

Authors: Durata Haciu, Ozgur Birer

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Zinc acetate solution is sonicated at high power in water and in ethanol in the absence and presence of various peroxides. In the absence of peroxides, the products are zinc oxide and layered hydroxy zinc acetate in water and in ethanol, respectively. Layered basic zinc acetate are prepared for the first time using sonochemical methods. The addition of peroxides alters the reaction mechanisms. In water, insoluble peroxides produce zinc oxides while the water soluble peroxide, i.e.hydrogen peroxide, completely destroyed the structure and casted a doubt on the accepted peroxide initiated mechanism of reactions. In ethanol,peroxide addition caused the reaction mechanism to change and some oxide formation is observed. The reaction mechanism is sensitive to water/ethanol amounts as well as the peroxide to zinc ion mole ratio.Thin zinc oxide wafers (ca. 30 nm) with band gaps of 3.24 eV were obtained.

Keywords: ultrasound, zinc oxide, hydroxy zinc acetate, fenton, peroxide initiation

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1023 Pharmacovigilance in Hospitals: Retrospective Study at the Pharmacovigilance Service of UHE-Oran, Algeria

Authors: Nadjet Mekaouche, Hanane Zitouni, Fatma Boudia, Habiba Fetati, A. Saleh, A. Lardjam, H. Geniaux, A. Coubret, H. Toumi

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Medicines have undeniably played a major role in prolonging shelf life and improving quality. The absolute efficacy of the drug remains a lever for innovation, its benefit/risk balance is not always assured and it does not always have the expected effects. Prior to marketing, knowledge about adverse drug reactions is incomplete. Once on the market, phase IV drug studies begin. For years, the drug was prescribed with less care to a large number of very heterogeneous patients and often in combination with other drugs. It is at this point that previously unknown adverse effects may appear, hence the need for the implementation of a pharmacovigilance system. Pharmacovigilance represents all methods for detecting, evaluating, informing and preventing the risks of adverse drug reactions. The most severe adverse events occur frequently in hospital and that a significant proportion of adverse events result in hospitalizations. In addition, the consequences of hospital adverse events in terms of length of stay, mortality and costs are considerable. It, therefore, appears necessary to develop ‘hospital pharmacovigilance’ aimed at reducing the incidence of adverse reactions in hospitals. The most widely used monitoring method in pharmacovigilance is spontaneous notification. However, underreporting of adverse drug reactions is common in many countries and is a major obstacle to pharmacovigilance assessment. It is in this context that this study aims to describe the experience of the pharmacovigilance service at the University Hospital of Oran (EHUO). This is a retrospective study extending from 2011 to 2017, carried out on archived records of declarations collected at the level of the EHUO Pharmacovigilance Department. Reporting was collected by two methods: ‘spontaneous notification’ and ‘active pharmacovigilance’ targeting certain clinical services. We counted 217 statements. It involved 56% female patients and 46% male patients. Age ranged from 5 to 78 years with an average of 46 years. The most common adverse reaction was drug toxidermy. For the drugs in question, they were essentially according to the ATC classification of anti-infectives followed by anticancer drugs. As regards the evolution of declarations by year, a low rate of notification was noted in 2011. That is why we decided to set up an active approach at the level of some services where a resident of reference attended the staffs every week. This has resulted in an increase in the number of reports. The declarations came essentially from the services where the active approach was installed. This highlights the need for ongoing communication between all relevant health actors to stimulate reporting and secure drug treatments.

Keywords: adverse drug reactions, hospital, pharmacovigilance, spontaneous notification

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1022 Teachers’ Reactions, Learning, Organizational Support, and Use of Lesson Study for Transformative Assessment

Authors: Melaku Takele Abate, Abbi Lemma Wodajo, Adula Bekele Hunde

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This study aimed at exploring mathematics teachers' reactions, learning, school leaders’ support, and use of the Lesson Study for Transformative Assessment (LSforTA) program ideas in practice. The LSforTA program was new, and therefore, a local and grounded approach was needed to examine teachers’ knowledge and skills acquired using LSforTA. So, a design-based research approach was selected to evaluate and refine the LSforTA approach. The results showed that LSforTA increased teachers' knowledge and use of different levels of mathematics assessment tasks. The program positively affected teachers' practices of transformative assessment and enhanced their knowledge and skills in assessing students in a transformative way. The paper concludes how the LSforTA procedures were adapted in response to this evaluation and provides suggestions for future development and research.

Keywords: classroom assessment, feedback practices, lesson study, mathematics, design-based research

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1021 Electrocatalysts for Lithium-Sulfur Energy Storage Systems

Authors: Mirko Ante, Şeniz Sörgel, Andreas Bund

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Li-S- (Lithium-Sulfur-) battery systems provide very high specific gravimetric energy (2600 Wh/kg) and volumetric energy density (2800Wh/l). Hence, Li-S batteries are one of the key technologies for both the upcoming electromobility and stationary applications. Furthermore, the Li-S battery system is potentially cheap and environmentally benign. However, the technical implementation suffers from cycling stability, low charge and discharge rates and incomplete understanding of the complex polysulfide reaction mechanism. The aim of this work is to develop an effective electrocatalyst for the polysulfide reactions so that the electrode kinetics of the sulfur half-cell will be improved. Accordingly, the overvoltage will be decreased, and the efficiency of the cell will be increased. An enhanced electroactive surface additionally improves the charge and discharge rates. To reach this goal, functionalized electrocatalytic coatings are investigated to accelerate the kinetics of the polysulfide reactions. In order to determine a suitable electrocatalyst, apparent exchange current densities of a variety of materials (Ni, Co, Pt, Cr, Al, Cu, ITO, stainless steel) have been evaluated in a polysulfide containing electrolyte by potentiodynamic measurements and a Butler-Volmer fit including diffusion limitation. The samples have been examined by Scanning Electron Microscopy (SEM) after the potentiodynamic measurements. Up to now, our work shows that cobalt is a promising material with good electrocatalytic properties for the polysulfide reactions and good chemical stability in the system. Furthermore, an electrodeposition from a modified Watt’s nickel electrolyte with a sulfur source seems to provide an autocatalytic effect, but the electrocatalytic behavior decreases after several cycles of the current-potential-curve.

Keywords: electrocatalyst, energy storage, lithium sulfur battery, sulfur electrode materials

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