Search results for: molecular interactions
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3895

Search results for: molecular interactions

445 Computational Approach to Identify Novel Chemotherapeutic Agents against Multiple Sclerosis

Authors: Syed Asif Hassan, Tabrej Khan

Abstract:

Multiple sclerosis (MS) is a chronic demyelinating autoimmune disorder, of the central nervous system (CNS). In the present scenario, the current therapies either do not halt the progression of the disease or have side effects which limit the usage of current Disease Modifying Therapies (DMTs) for a longer period of time. Therefore, keeping the current treatment failure schema, we are focusing on screening novel analogues of the available DMTs that specifically bind and inhibit the Sphingosine1-phosphate receptor1 (S1PR1) thereby hindering the lymphocyte propagation toward CNS. The novel drug-like analogs molecule will decrease the frequency of relapses (recurrence of the symptoms associated with MS) with higher efficacy and lower toxicity to human system. In this study, an integrated approach involving ligand-based virtual screening protocol (Ultrafast Shape Recognition with CREDO Atom Types (USRCAT)) to identify the non-toxic drug like analogs of the approved DMTs were employed. The potency of the drug-like analog molecules to cross the Blood Brain Barrier (BBB) was estimated. Besides, molecular docking and simulation using Auto Dock Vina 1.1.2 and GOLD 3.01 were performed using the X-ray crystal structure of Mtb LprG protein to calculate the affinity and specificity of the analogs with the given LprG protein. The docking results were further confirmed by DSX (DrugScore eXtented), a robust program to evaluate the binding energy of ligands bound to the ligand binding domain of the Mtb LprG lipoprotein. The ligand, which has a higher hypothetical affinity, also has greater negative value. Further, the non-specific ligands were screened out using the structural filter proposed by Baell and Holloway. Based on the USRCAT, Lipinski’s values, toxicity and BBB analysis, the drug-like analogs of fingolimod and BG-12 showed that RTL and CHEMBL1771640, respectively are non-toxic and permeable to BBB. The successful docking and DSX analysis showed that RTL and CHEMBL1771640 could bind to the binding pocket of S1PR1 receptor protein of human with greater affinity than as compared to their parent compound (Fingolimod). In this study, we also found that all the drug-like analogs of the standard MS drugs passed the Bell and Holloway filter.

Keywords: antagonist, binding affinity, chemotherapeutics, drug-like, multiple sclerosis, S1PR1 receptor protein

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444 An Approach for the Capture of Carbon Dioxide via Polymerized Ionic Liquids

Authors: Ghassan Mohammad Alalawi, Abobakr Khidir Ziyada, Abdulmajeed Khan

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A potential alternative or next-generation CO₂-selective separation medium that has lately been suggested is ionic liquids (ILs). It is more facile to "tune" the solubility and selectivity of CO₂ in ILs compared to organic solvents via modification of the cation and/or anion structures. Compared to ionic liquids at ambient temperature, polymerized ionic liquids exhibited increased CO₂ sorption capacities and accelerated sorption/desorption rates. This research aims to investigate the correlation between the CO₂ sorption rate and capacity of poly ionic liquids (pILs) and the chemical structure of these substances. The dependency of sorption on the ion conductivity of the pILs' cations and anions is one of the theories we offered to explain the attraction between CO₂ and pILs. This assumption was supported by the Monte Carlo molecular dynamics simulations results, which demonstrated that CO₂ molecules are localized around both cations and anions and that their sorption depends on the cations' and anions' ion conductivities. Polymerized ionic liquids are synthesized to investigate the impact of substituent alkyl chain length, cation, and anion on CO₂ sorption rate and capacity. Three stages are involved in synthesizing the pILs under study: first, trialkyl amine and vinyl benzyl chloride are directly quaternized to obtain the required cation. Next, anion exchange is performed, and finally, the obtained IL is polymerized to form the desired product (pILs). The synthesized pILs' structures were confirmed using elemental analysis and NMR. The synthesized pILs are characterized by examining their structure topology, chloride content, density, and thermal stability using SEM, ion chromatography (using a Metrohm Model 761 Compact IC apparatus), ultrapycnometer, and TGA. As determined by the CO₂ sorption results using a magnetic suspension balance (MSB) apparatus, the sorption capacity of pILs is dependent on the cation and anion ion conductivities. The anion's size also influences the CO₂ sorption rate and capacity. It was discovered that adding water to pILs caused a dramatic, systematic enlargement of pILs resulting in a significant increase in their capacity to absorb CO₂ under identical conditions, contingent on the type of gas, gas flow, applied gas pressure, and water content of the pILs. Along with its capacity to increase surface area through expansion, water also possesses highly high ion conductivity for cations and anions, enhancing its ability to absorb CO₂.

Keywords: polymerized ionic liquids, carbon dioxide, swelling, characterization

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443 Cognitive Deficits and Association with Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder in 22q11.2 Deletion Syndrome

Authors: Sinead Morrison, Ann Swillen, Therese Van Amelsvoort, Samuel Chawner, Elfi Vergaelen, Michael Owen, Marianne Van Den Bree

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22q11.2 Deletion Syndrome (22q11.2DS) is caused by the deletion of approximately 60 genes on chromosome 22 and is associated with high rates of neurodevelopmental disorders such as Attention Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorders (ASD). The presentation of these disorders in 22q11.2DS is reported to be comparable to idiopathic forms and therefore presents a valuable model for understanding mechanisms of neurodevelopmental disorders. Cognitive deficits are thought to be a core feature of neurodevelopmental disorders, and possibly manifest in behavioural and emotional problems. There have been mixed findings in 22q11.2DS on whether the presence of ADHD or ASD is associated with greater cognitive deficits. Furthermore, the influence of developmental stage has never been taken into account. The aim was therefore to examine whether the presence of ADHD or ASD was associated with cognitive deficits in childhood and/or adolescence in 22q11.2DS. We conducted the largest study to date of this kind in 22q11.2DS. The same battery of tasks measuring processing speed, attention and spatial working memory were completed by 135 participants with 22q11.2DS. Wechsler IQ tests were completed, yielding Full Scale (FSIQ), Verbal (VIQ) and Performance IQ (PIQ). Age-standardised difference scores were produced for each participant. Developmental stages were defined as children (6-10 years) and adolescents (10-18 years). ADHD diagnosis was ascertained from a semi-structured interview with a parent. ASD status was ascertained from a questionnaire completed by a parent. Interaction and main effects of cognitive performance of those with or without a diagnosis of ADHD or ASD in childhood or adolescence were conducted with 2x2 ANOVA. Significant interactions were followed up with t-tests of simple effects. Adolescents with ASD displayed greater deficits in all measures (processing speed, p = 0.022; sustained attention, p = 0.016; working memory, p = 0.006) than adolescents without ASD; there was no difference between children with and without ASD. There were no significant differences on IQ measures. Both children and adolescents with ADHD displayed greater deficits on sustained attention (p = 0.002) than those without ADHD. There were no significant differences on any other measures for ADHD. Magnitude of cognitive deficit in individuals with 22q11.2DS varied by cognitive domain, developmental stage and presence of neurodevelopmental disorder. Adolescents with 22q11.2DS and ASD showed greater deficits on all measures, which suggests there may be a sensitive period in childhood to acquire these domains, or reflect increasing social and academic demands in adolescence. The finding of poorer sustained attention in children and adolescents with ADHD supports previous research and suggests a specific deficit which can be separated from processing speed and working memory. This research provides unique insights into the association of ASD and ADHD with cognitive deficits in a group at high genomic risk of neurodevelopmental disorders.

Keywords: 22q11.2 deletion syndrome, attention deficit hyperactivity disorder, autism spectrum disorder, cognitive development

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442 Dimensionality Control of Li Transport by MOFs Based Quasi-Solid to Solid Electrolyte

Authors: Manuel Salado, Mikel Rincón, Arkaitz Fidalgo, Roberto Fernandez, Senentxu Lanceros-Méndez

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Lithium-ion batteries (LIBs) are a promising technology for energy storage, but they suffer from safety concerns due to the use of flammable organic solvents in their liquid electrolytes. Solid-state electrolytes (SSEs) offer a potential solution to this problem, but they have their own limitations, such as poor ionic conductivity and high interfacial resistance. The aim of this research was to develop a new type of SSE based on metal-organic frameworks (MOFs) and ionic liquids (ILs). MOFs are porous materials with high surface area and tunable electronic properties, making them ideal for use in SSEs. ILs are liquid electrolytes that are non-flammable and have high ionic conductivity. A series of MOFs were synthesized, and their electrochemical properties were evaluated. The MOFs were then infiltrated with ILs to form a quasi-solid gel and solid xerogel SSEs. The ionic conductivity, interfacial resistance, and electrochemical performance of the SSEs were characterized. The results showed that the MOF-IL SSEs had significantly higher ionic conductivity and lower interfacial resistance than conventional SSEs. The SSEs also exhibited excellent electrochemical performance, with high discharge capacity and long cycle life. The development of MOF-IL SSEs represents a significant advance in the field of solid-state electrolytes. The high ionic conductivity and low interfacial resistance of the SSEs make them promising candidates for use in next-generation LIBs. The data for this research was collected using a variety of methods, including X-ray diffraction, scanning electron microscopy, and electrochemical impedance spectroscopy. The data was analyzed using a variety of statistical and computational methods, including principal component analysis, density functional theory, and molecular dynamics simulations. The main question addressed by this research was whether MOF-IL SSEs could be developed that have high ionic conductivity, low interfacial resistance, and excellent electrochemical performance. The results of this research demonstrate that MOF-IL SSEs are a promising new type of solid-state electrolyte for use in LIBs. The SSEs have high ionic conductivity, low interfacial resistance, and excellent electrochemical performance. These properties make them promising candidates for use in next-generation LIBs that are safer and have higher energy densities.

Keywords: energy storage, solid-electrolyte, ionic liquid, metal-organic-framework, electrochemistry, organic inorganic plastic crystal

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441 Bioactive Substances-Loaded Water-in-Oil/Oil-in-Water Emulsions for Dietary Supplementation in the Elderly

Authors: Agnieszka Markowska-Radomska, Ewa Dluska

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Maintaining a bioactive substances dense diet is important for the elderly, especially to prevent diseases and to support healthy ageing. Adequate bioactive substances intake can reduce the risk of developing chronic diseases (e.g. cardiovascular, osteoporosis, neurodegenerative syndromes, diseases of the oral cavity, gastrointestinal (GI) disorders, diabetes, and cancer). This can be achieved by introducing a comprehensive supplementation of components necessary for the proper functioning of the ageing body. The paper proposes the multiple emulsions of the W1/O/W2 (water-in-oil-in-water) type as carriers for effective co-encapsulation and co-delivery of bioactive substances in supplementation of the elderly. Multiple emulsions are complex structured systems ("drops in drops"). The functional structure of the W1/O/W2 emulsion enables (i) incorporation of one or more bioactive components (lipophilic and hydrophilic); (ii) enhancement of stability and bioavailability of encapsulated substances; (iii) prevention of interactions between substances, as well as with the external environment, delivery to a specific location; and (iv) release in a controlled manner. The multiple emulsions were prepared by a one-step method in the Couette-Taylor flow (CTF) contactor in a continuous manner. In general, a two-step emulsification process is used to obtain multiple emulsions. The paper contains a proposal of emulsion functionalization by introducing pH-responsive biopolymer—carboxymethylcellulose sodium salt (CMC-Na) to the external phase, which made it possible to achieve a release of components controlled by the pH of the gastrointestinal environment. The membrane phase of emulsions was soybean oil. The W1/O/W2 emulsions were evaluated for their characteristics (drops size/drop size distribution, volume packing fraction), encapsulation efficiency and stability during storage (to 30 days) at 4ºC and 25ºC. Also, the in vitro multi-substance co-release process were investigated in a simulated gastrointestinal environment (different pH and composition of release medium). Three groups of stable multiple emulsions were obtained: emulsions I with co-encapsulated vitamins B12, B6 and resveratrol; emulsions II with vitamin A and β-carotene; and emulsions III with vitamins C, E and D3. The substances were encapsulated in the appropriate emulsion phases depending on the solubility. For all emulsions, high encapsulation efficience (over 95%) and high volume packing fraction of internal droplets (0.54-0.76) were reached. In addition, due to the presence of a polymer (CMC-Na) with adhesive properties, high encapsulation stability during emulsions storage were achieved. The co-release study of encapsulated bioactive substances confirmed the possibility to modify the release profiles. It was found that the releasing process can be controlled through the composition, structure, physicochemical parameters of emulsions and pH of the release medium. The results showed that the obtained multiple emulsions might be used as potential liquid complex carriers for controlled/modified/site-specific co-delivery of bioactive substances in dietary supplementation in the elderly.

Keywords: bioactive substance co-release, co-encapsulation, elderly supplementation, multiple emulsion

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440 Analysis of Influencing Factors on Infield-Logistics: A Survey of Different Farm Types in Germany

Authors: Michael Mederle, Heinz Bernhardt

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The Management of machine fleets or autonomous vehicle control will considerably increase efficiency in future agricultural production. Especially entire process chains, e.g. harvesting complexes with several interacting combine harvesters, grain carts, and removal trucks, provide lots of optimization potential. Organization and pre-planning ensure to get these efficiency reserves accessible. One way to achieve this is to optimize infield path planning. Particularly autonomous machinery requires precise specifications about infield logistics to be navigated effectively and process optimized in the fields individually or in machine complexes. In the past, a lot of theoretical optimization has been done regarding infield logistics, mainly based on field geometry. However, there are reasons why farmers often do not apply the infield strategy suggested by mathematical route planning tools. To make the computational optimization more useful for farmers this study focuses on these influencing factors by expert interviews. As a result practice-oriented navigation not only to the field but also within the field will be possible. The survey study is intended to cover the entire range of German agriculture. Rural mixed farms with simple technology equipment are considered as well as large agricultural cooperatives which farm thousands of hectares using track guidance and various other electronic assistance systems. First results show that farm managers using guidance systems increasingly attune their infield-logistics on direction giving obstacles such as power lines. In consequence, they can avoid inefficient boom flippings while doing plant protection with the sprayer. Livestock farmers rather focus on the application of organic manure with its specific requirements concerning road conditions, landscape terrain or field access points. Cultivation of sugar beets makes great demands on infield patterns because of its particularities such as the row crop system or high logistics demands. Furthermore, several machines working in the same field simultaneously influence each other, regardless whether or not they are of the equal type. Specific infield strategies always are based on interactions of several different influences and decision criteria. Single working steps like tillage, seeding, plant protection or harvest mostly cannot be considered each individually. The entire production process has to be taken into consideration to detect the right infield logistics. One long-term objective of this examination is to integrate the obtained influences on infield strategies as decision criteria into an infield navigation tool. In this way, path planning will become more practical for farmers which is a basic requirement for automatic vehicle control and increasing process efficiency.

Keywords: autonomous vehicle control, infield logistics, path planning, process optimizing

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439 The Usefulness of Premature Chromosome Condensation Scoring Module in Cell Response to Ionizing Radiation

Authors: K. Rawojć, J. Miszczyk, A. Możdżeń, A. Panek, J. Swakoń, M. Rydygier

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Due to the mitotic delay, poor mitotic index and disappearance of lymphocytes from peripheral blood circulation, assessing the DNA damage after high dose exposure is less effective. Conventional chromosome aberration analysis or cytokinesis-blocked micronucleus assay do not provide an accurate dose estimation or radiosensitivity prediction in doses higher than 6.0 Gy. For this reason, there is a need to establish reliable methods allowing analysis of biological effects after exposure in high dose range i.e., during particle radiotherapy. Lately, Premature Chromosome Condensation (PCC) has become an important method in high dose biodosimetry and a promising treatment modality to cancer patients. The aim of the study was to evaluate the usefulness of drug-induced PCC scoring procedure in an experimental mode, where 100 G2/M cells were analyzed in different dose ranges. To test the consistency of obtained results, scoring was performed by 3 independent persons in the same mode and following identical scoring criteria. Whole-body exposure was simulated in an in vitro experiment by irradiating whole blood collected from healthy donors with 60 MeV protons and 250 keV X-rays, in the range of 4.0 – 20.0 Gy. Drug-induced PCC assay was performed on human peripheral blood lymphocytes (HPBL) isolated after in vitro exposure. Cells were cultured for 48 hours with PHA. Then to achieve premature condensation, calyculin A was added. After Giemsa staining, chromosome spreads were photographed and manually analyzed by scorers. The dose-effect curves were derived by counting the excess chromosome fragments. The results indicated adequate dose estimates for the whole-body exposure scenario in the high dose range for both studied types of radiation. Moreover, compared results revealed no significant differences between scores, which has an important meaning in reducing the analysis time. These investigations were conducted as a part of an extended examination of 60 MeV protons from AIC-144 isochronous cyclotron, at the Institute of Nuclear Physics in Kraków, Poland (IFJ PAN) by cytogenetic and molecular methods and were partially supported by grant DEC-2013/09/D/NZ7/00324 from the National Science Centre, Poland.

Keywords: cell response to radiation exposure, drug induced premature chromosome condensation, premature chromosome condensation procedure, proton therapy

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438 The Cost of Beauty: Insecurity and Profit

Authors: D. Cole, S. Mahootian, P. Medlock

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This research contributes to existing knowledge of the complexities surrounding women’s relationship to beauty standards by examining their lived experiences. While there is much academic work on the effects of culturally imposed and largely unattainable beauty standards, the arguments tend to fall into two paradigms. On the one hand is the radical feminist perspective that argues that women are subjected to absolute oppression within the patriarchal system in which beauty standards have been constructed. This position advocates for a complete restructuring of social institutions to liberate women from all types of oppression. On the other hand, there are liberal feminist arguments that focus on choice, arguing that women’s agency in how to present themselves is empowerment. These arguments center around what women do within the patriarchal system in order to liberate themselves. However, there is very little research on the lived experiences of women negotiating these two realms: the complex negotiation between the pressure to adhere to cultural beauty standards and the agency of self-expression and empowerment. By exploring beauty standards through the intersection of societal messages (including macro-level processes such as social media and advertising as well as smaller-scale interactions such as families and peers) and lived experiences, this study seeks to provide a nuanced understanding of how women navigate and negotiate their own presentation and sense of self-identity. Current research sees a rise in incidents of body dysmorphia, depression and anxiety since the advent of social media. Approximately 91% of women are unhappy with their bodies and resort to dieting to achieve their ideal body shape, but only 5% of women naturally possess the body type often portrayed by Americans in movies and media. It is, therefore, crucial we begin talking about the processes that are affecting self-image and mental health. A question that arises is that, given these negative effects, why do companies continue to advertise and target women with standards that very few could possibly attain? One obvious answer is that keeping beauty standards largely unattainable enables the beauty and fashion industries to make large profits by promising products and procedures that will bring one up to “standard”. The creation of dissatisfaction for some is profit for others. This research utilizes qualitative methods: interviews, questionnaires, and focus groups to investigate women’s relationships to beauty standards and empowerment. To this end, we reached out to potential participants through a video campaign on social media: short clips on Instagram, Facebook, and TikTok and a longer clip on YouTube inviting users to take part in the study. Participants are asked to react to images, videos, and other beauty-related texts. The findings of this research have implications for policy development, advocacy and interventions aimed at promoting healthy inclusivity and empowerment of women.

Keywords: women, beauty, consumerism, social media

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437 Morphological and Molecular Evaluation of Dengue Virus Serotype 3 Infection in BALB/c Mice Lungs

Authors: Gabriela C. Caldas, Fernanda C. Jacome, Arthur da C. Rasinhas, Ortrud M. Barth, Flavia B. dos Santos, Priscila C. G. Nunes, Yuli R. M. de Souza, Pedro Paulo de A. Manso, Marcelo P. Machado, Debora F. Barreto-Vieira

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The establishment of animal models for studies of DENV infections has been challenging, since circulating epidemic viruses do not naturally infect nonhuman species. Such studies are of great relevance to the various areas of dengue research, including immunopathogenesis, drug development and vaccines. In this scenario, the main objective of this study is to verify possible morphological changes, as well as the presence of antigens and viral RNA in lung samples from BALB/c mice experimentally infected with an epidemic and non-neuroadapted DENV-3 strain. Male BALB/c mice, 2 months old, were inoculated with DENV-3 by intravenous route. After 72 hours of infection, the animals were euthanized and the lungs were collected. Part of the samples was processed by standard technique for analysis by light and transmission electronic microscopies and another part was processed for real-time PCR analysis. Morphological analyzes of lungs from uninfected mice showed preserved tissue areas. In mice infected with DENV-3, the analyzes revealed interalveolar septum thickening with presence of inflammatory infiltrate, foci of alveolar atelectasis and hyperventilation, bleeding foci in the interalveolar septum and bronchioles, peripheral capillary congestion, accumulation of fluid in the blood capillary, signs of interstitial cell necrosis presence of platelets and mononuclear inflammatory cells circulating in the capillaries and/or adhered to the endothelium. In addition, activation of endothelial cells, platelets, mononuclear inflammatory cell and neutrophil-type polymorphonuclear inflammatory cell evidenced by the emission of cytoplasmic membrane prolongation was observed. DEN-like particles were seen in the cytoplasm of endothelial cells. The viral genome was recovered from 3 in 12 lung samples. These results demonstrate that the BALB / c mouse represents a suitable model for the study of the histopathological changes induced by DENV infection in the lung, with tissue alterations similar to those observed in human cases of DEN.

Keywords: BALB/c mice, dengue, histopathology, lung, ultrastructure

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436 Biophysical Analysis of the Interaction of Polymeric Nanoparticles with Biomimetic Models of the Lung Surfactant

Authors: Weiam Daear, Patrick Lai, Elmar Prenner

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The human body offers many avenues that could be used for drug delivery. The pulmonary route, which is delivered through the lungs, presents many advantages that have sparked interested in the field. These advantages include; 1) direct access to the lungs and the large surface area it provides, and 2) close proximity to the blood circulation. The air-blood barrier of the alveoli is about 500 nm thick. The air-blood barrier consist of a monolayer of lipids and few proteins called the lung surfactant and cells. This monolayer consists of ~90% lipids and ~10% proteins that are produced by the alveolar epithelial cells. The two major lipid classes constitutes of various saturation and chain length of phosphatidylcholine (PC) and phosphatidylglycerol (PG) representing 80% of total lipid component. The major role of the lung surfactant monolayer is to reduce surface tension experienced during breathing cycles in order to prevent lung collapse. In terms of the pulmonary drug delivery route, drugs pass through various parts of the respiratory system before reaching the alveoli. It is at this location that the lung surfactant functions as the air-blood barrier for drugs. As the field of nanomedicine advances, the use of nanoparticles (NPs) as drug delivery vehicles is becoming very important. This is due to the advantages NPs provide with their large surface area and potential specific targeting. Therefore, studying the interaction of NPs with lung surfactant and whether they affect its stability becomes very essential. The aim of this research is to develop a biomimetic model of the human lung surfactant followed by a biophysical analysis of the interaction of polymeric NPs. This biomimetic model will function as a fast initial mode of testing for whether NPs affect the stability of the human lung surfactant. The model developed thus far is an 8-component lipid system that contains major PC and PG lipids. Recently, a custom made 16:0/16:1 PC and PG lipids were added to the model system. In the human lung surfactant, these lipids constitute 16% of the total lipid component. According to the author’s knowledge, there is not much monolayer data on the biophysical analysis of the 16:0/16:1 lipids, therefore more analysis will be discussed here. Biophysical techniques such as the Langmuir Trough is used for stability measurements which monitors changes to a monolayer's surface pressure upon NP interaction. Furthermore, Brewster Angle Microscopy (BAM) employed to visualize changes to the lateral domain organization. Results show preferential interactions of NPs with different lipid groups that is also dependent on the monolayer fluidity. Furthermore, results show that the film stability upon compression is unaffected, but there are significant changes in the lateral domain organization of the lung surfactant upon NP addition. This research is significant in the field of pulmonary drug delivery. It is shown that NPs within a certain size range are safe for the pulmonary route, but little is known about the mode of interaction of those polymeric NPs. Moreover, this work will provide additional information about the nanotoxicology of NPs tested.

Keywords: Brewster angle microscopy, lipids, lung surfactant, nanoparticles

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435 De Novo Assembly and Characterization of the Transcriptome from the Fluoroacetate Producing Plant, Dichapetalum Cymosum

Authors: Selisha A. Sooklal, Phelelani Mpangase, Shaun Aron, Karl Rumbold

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Organically bound fluorine (C-F bond) is extremely rare in nature. Despite this, the first fluorinated secondary metabolite, fluoroacetate, was isolated from the plant Dichapetalum cymosum (commonly known as Gifblaar). However, the enzyme responsible for fluorination (fluorinase) in Gifblaar was never isolated and very little progress has been achieved in understanding this process in higher plants. Fluorinated compounds have vast applications in the pharmaceutical, agrochemical and fine chemicals industries. Consequently, an enzyme capable of catalysing a C-F bond has great potential as a biocatalyst in the industry considering that the field of fluorination is virtually synthetic. As with any biocatalyst, a range of these enzymes are required. Therefore, it is imperative to expand the exploration for novel fluorinases. This study aimed to gain molecular insights into secondary metabolite biosynthesis in Gifblaar using a high-throughput sequencing-based approach. Mechanical wounding studies were performed using Gifblaar leaf tissue in order to induce expression of the fluorinase. The transcriptome of the wounded and unwounded plant was then sequenced on the Illumina HiSeq platform. A total of 26.4 million short sequence reads were assembled into 77 845 transcripts using Trinity. Overall, 68.6 % of transcripts were annotated with gene identities using public databases (SwissProt, TrEMBL, GO, COG, Pfam, EC) with an E-value threshold of 1E-05. Sequences exhibited the greatest homology to the model plant, Arabidopsis thaliana (27 %). A total of 244 annotated transcripts were found to be differentially expressed between the wounded and unwounded plant. In addition, secondary metabolic pathways present in Gifblaar were successfully reconstructed using Pathway tools. Due to lack of genetic information for plant fluorinases, a transcript failed to be annotated as a fluorinating enzyme. Thus, a local database containing the 5 existing bacterial fluorinases was created. Fifteen transcripts having homology to partial regions of existing fluorinases were found. In efforts to obtain the full coding sequence of the Gifblaar fluorinase, primers were designed targeting the regions of homology and genome walking will be performed to amplify the unknown regions. This is the first genetic data available for Gifblaar. It has provided novel insights into the mechanisms of metabolite biosynthesis and will allow for the discovery of the first eukaryotic fluorinase.

Keywords: biocatalyst, fluorinase, gifblaar, transcriptome

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434 Statistical Optimization of Adsorption of a Harmful Dye from Aqueous Solution

Authors: M. Arun, A. Kannan

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Textile industries cater to varied customer preferences and contribute substantially to the economy. However, these textile industries also produce a considerable amount of effluents. Prominent among these are the azo dyes which impart considerable color and toxicity even at low concentrations. Azo dyes are also used as coloring agents in food and pharmaceutical industry. Despite their applications, azo dyes are also notorious pollutants and carcinogens. Popular techniques like photo-degradation, biodegradation and the use of oxidizing agents are not applicable for all kinds of dyes, as most of them are stable to these techniques. Chemical coagulation produces a large amount of toxic sludge which is undesirable and is also ineffective towards a number of dyes. Most of the azo dyes are stable to UV-visible light irradiation and may even resist aerobic degradation. Adsorption has been the most preferred technique owing to its less cost, high capacity and process efficiency and the possibility of regenerating and recycling the adsorbent. Adsorption is also most preferred because it may produce high quality of the treated effluent and it is able to remove different kinds of dyes. However, the adsorption process is influenced by many variables whose inter-dependence makes it difficult to identify optimum conditions. The variables include stirring speed, temperature, initial concentration and adsorbent dosage. Further, the internal diffusional resistance inside the adsorbent particle leads to slow uptake of the solute within the adsorbent. Hence, it is necessary to identify optimum conditions that lead to high capacity and uptake rate of these pollutants. In this work, commercially available activated carbon was chosen as the adsorbent owing to its high surface area. A typical azo dye found in textile effluent waters, viz. the monoazo Acid Orange 10 dye (CAS: 1936-15-8) has been chosen as the representative pollutant. Adsorption studies were mainly focused at obtaining equilibrium and kinetic data for the batch adsorption process at different process conditions. Studies were conducted at different stirring speed, temperature, adsorbent dosage and initial dye concentration settings. The Full Factorial Design was the chosen statistical design framework for carrying out the experiments and identifying the important factors and their interactions. The optimum conditions identified from the experimental model were validated with actual experiments at the recommended settings. The equilibrium and kinetic data obtained were fitted to different models and the model parameters were estimated. This gives more details about the nature of adsorption taking place. Critical data required to design batch adsorption systems for removal of Acid Orange 10 dye and identification of factors that critically influence the separation efficiency are the key outcomes from this research.

Keywords: acid orange 10, activated carbon, optimum adsorption conditions, statistical design

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433 Anti-Neuroinflammatory and Anti-Apoptotic Efficacy of Equol, against Lipopolysaccharide Activated Microglia and Its Neurotoxicity

Authors: Lalita Subedi, Jae Kyoung Chae, Yong Un Park, Cho Kyo Hee, Lee Jae Hyuk, Kang Min Cheol, Sun Yeou Kim

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Neuroinflammation may mediate the relationship between low levels of estrogens and neurodegenerative disease. Estrogens are neuroprotective and anti-inflammatory in neurodegenerative disease models. Due to the long term side effects of estrogens, researches have been focused on finding an effective phytoestrogens for biological activities. Daidzein present in soybeans and its active metabolite equol (7-hydroxy-3-(4'-hydroxyphenyl)-chroman) bears strong antioxidant and anticancer showed more potent anti-inflammatory and neuroprotective role in neuroinflammatory model confirmed its in vitro activity with molecular mechanism through NF-κB pathway. Three major CNS cells Microglia (BV-2), Astrocyte (C6), Neuron (N2a) were used to find the effect of equol in inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), MAPKs signaling proteins, apoptosis related proteins by western blot analysis. Nitric oxide (NO) and prostaglandin E2 (PGE2) was measured by the Gries method and ELISA, respectively. Cytokines like tumor necrosis factor-α (TNF-α) and IL-6 were also measured in the conditioned medium of LPS activated cells with or without equol. Equol inhibited the NO production, PGE-2 production and expression of COX-2 and iNOS in LPS-stimulated microglial cells at a dose dependent without any cellular toxicity. At the same time Equol also showed promising effect in modulation of MAPK’s and nuclear factor kappa B (NF-κB) expression with significant inhibition of the production of proinflammatory cytokine like interleukin -6 (IL-6), and tumor necrosis factor -α (TNF-α). Additionally, it inhibited the LPS activated microglia-induced neuronal cell death by downregulating the apoptotic phenomenon in neuronal cells. Furthermore, equol increases the production of neurotrophins like NGF and increase the neurite outgrowth as well. In conclusion the natural daidzein metabolite equol are more active than daidzein, which showed a promising effectiveness as an anti-neuroinflammatory and neuroprotective agent via downregulating the LPS stimulated microglial activation and neuronal apoptosis. This work was supported by Brain Korea 21 Plus project and High Value-added Food Technology Development Program 114006-4, Ministry of Agriculture, Food and Rural Affairs.

Keywords: apoptosis, equol, neuroinflammation, phytoestrogen

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432 Virtual Learning during the Period of COVID-19 Pandemic at a Saudi University

Authors: Ahmed Mohammed Omer Alghamdi

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Since the COVID-19 pandemic started, a rapid, unexpected transition from face-to-face to virtual classroom (VC) teaching has involved several challenges and obstacles. However, there are also opportunities and thoughts that need to be examined and discussed. In addition, the entire world is witnessing that the teaching system and, more particularly, higher education institutes have been interrupted. To maintain the learning and teaching practices as usual, countries were forced to transition from traditional to virtual classes using various technology-based devices. In this regard, the Kingdom of Saudi Arabia (KSA) is no exception. Focusing on how the current situation has forced many higher education institutes to change to virtual classes may possibly provide a clear insight into adopted practices and implications. The main purpose of this study, therefore, was to investigate how both Saudi English as a foreign language (EFL) teachers and students perceived the implementation of virtual classes as a key factor for useful language teaching and learning process during the COVID-19 pandemic period at a Saudi university. The impetus for the research was, therefore, the need to find ways of identifying the deficiencies in this application and to suggest possible solutions that might rectify those deficiencies. This study seeks to answer the following overarching research question: “How do Saudi EFL instructors and students perceive the use of virtual classes during the COVID-19 pandemic period in their language teaching and learning context?” The following sub-questions are also used to guide the design of the study to answer the main research question: (1) To what extent are virtual classes important intra-pandemic from Saudi EFL instructors’ and students’ perspectives? (2) How effective are virtual classes for fostering English language students’ achievement? (3) What are the challenges and obstacles that instructors and students may face during the implementation of virtual teaching? A mixed method approach was employed in this study; the questionnaire data collection represented the quantitative method approach for this study, whereas the transcripts of recorded interviews represented the qualitative method approach. The participants included EFL teachers (N = 4) and male and female EFL students (N = 36). Based on the findings of this study, various aspects from teachers' and students’ perspectives were examined to determine the use of the virtual classroom applications in terms of fulfilling the students’ English language learning needs. The major findings of the study revealed that the virtual classroom applications during the current pandemic situation encountered three major challenges, among which the existence of the following essential aspects, namely lack of technology and an internet connection, having a large number of students in a virtual classroom and lack of students’ and teachers’ interactions during the virtual classroom applications. Finally, the findings indicated that although Saudi EFL students and teachers view the virtual classrooms in a positive light during the pandemic period, they reported that for long and post-pandemic period, they preferred the traditional face-to-face teaching procedure.

Keywords: virtual classes, English as a foreign language, COVID-19, Internet, pandemic

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431 'Utsadhara': Rejuvenating the Dead River Edge into an Urban Activity Space along the Banks of River Hooghly

Authors: Aparna Saha, Tuhin Ahmed

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West Bengal has a number of important rivers, each with its distinctive character and a story. Traditionally, cities have ‘divulged’ to rivers at the river edges and rivers have been an inseparable part of the urban experience. Considering the research aspect, the area is taken in Barrackpore, a small but important outgrowth of Kolkata Municipal Association, West Bengal. Barrackpore, at present, has ample inadequate public open spaces at the neighborhood level where people of different socio-cultural, economic, and religious backgrounds can come together and engage in various leisure activities, but there is no opportunity either, where people can learn about and explore the rich history of the settlement. Pertaining to these issues forms the backdrop of this research paper which has been conceptualized as a place from space that will bring people back to the river and increase community interactions and will also celebrate and commemorate towards the historical importance of the river and its edges. The entire precinct bordering the river represents the transition from pre-independence (Raj era) to Sepoy phase (Swaraj era), finally culminating into the Gandhian philosophy which is being projected into the already existing Gandhi Ghat. The ultimate aim of the paper entitled ‘Utsadhara- Rejuvenating the dead river edge into an urban activity space along the banks of river Hooghly’ is to create a socio-cultural space keeping the heritage identity intact through judicious use of the water body. Also, a balance is kept between the natural ecosystem and the cosmetic development of the surrounding open spaces. It can be duly achieved by the aforementioned methodology provided in the document, but mainly it would focus into preserving the historic ethnicity of the place by holding its character through various facts and figures as well as features. Most importantly the natural topography of the place is left intact. The second priority is given in terms of hierarchy of well connected public plazas, podiums where people from different socio-economic backgrounds irrespective of age and sex could socialize and reach towards venturing into a cordial relationship with one another. The third priority is to provide a platform for the common mass for showcasing their skills and talent through different art and craft forms which in turn would enhance their individual self and also the community as a whole through economic rise. Apart from this here some spaces are created in accordance to different age groups or class of people. The paper intends to see the river as a major multifunctional public space to attract people for different activities and re-establish the relationship of the river with the settlement. Hence, it is apprehended that the paper is not only intended to a simple riverfront conservation project but unlike others it is a place which is created for the people, by the people and of the people towards a holistic community development through a sustainable approach.

Keywords: holistic community development, public activity space, river-urban precinct, urban dead space

Procedia PDF Downloads 115
430 A Generalized Framework for Adaptive Machine Learning Deployments in Algorithmic Trading

Authors: Robert Caulk

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A generalized framework for adaptive machine learning deployments in algorithmic trading is introduced, tested, and released as open-source code. The presented software aims to test the hypothesis that recent data contains enough information to form a probabilistically favorable short-term price prediction. Further, the framework contains various adaptive machine learning techniques that are geared toward generating profit during strong trends and minimizing losses during trend changes. Results demonstrate that this adaptive machine learning approach is capable of capturing trends and generating profit. The presentation also discusses the importance of defining the parameter space associated with the dynamic training data-set and using the parameter space to identify and remove outliers from prediction data points. Meanwhile, the generalized architecture enables common users to exploit the powerful machinery while focusing on high-level feature engineering and model testing. The presentation also highlights common strengths and weaknesses associated with the presented technique and presents a broad range of well-tested starting points for feature set construction, target setting, and statistical methods for enforcing risk management and maintaining probabilistically favorable entry and exit points. The presentation also describes the end-to-end data processing tools associated with FreqAI, including automatic data fetching, data aggregation, feature engineering, safe and robust data pre-processing, outlier detection, custom machine learning and statistical tools, data post-processing, and adaptive training backtest emulation, and deployment of adaptive training in live environments. Finally, the generalized user interface is also discussed in the presentation. Feature engineering is simplified so that users can seed their feature sets with common indicator libraries (e.g. TA-lib, pandas-ta). The user also feeds data expansion parameters to fill out a large feature set for the model, which can contain as many as 10,000+ features. The presentation describes the various object-oriented programming techniques employed to make FreqAI agnostic to third-party libraries and external data sources. In other words, the back-end is constructed in such a way that users can leverage a broad range of common regression libraries (Catboost, LightGBM, Sklearn, etc) as well as common Neural Network libraries (TensorFlow, PyTorch) without worrying about the logistical complexities associated with data handling and API interactions. The presentation finishes by drawing conclusions about the most important parameters associated with a live deployment of the adaptive learning framework and provides the road map for future development in FreqAI.

Keywords: machine learning, market trend detection, open-source, adaptive learning, parameter space exploration

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429 The Theotokos of the Messina Missal as a Byzantine Icon in Norman Sicily: A Study on Patronage and Devotion

Authors: Jesus Rodriguez Viejo

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The aim of this paper is to study cross-cultural interactions between the West and Byzantium, in the fields of art and religion, by analyzing the decoration of one luxury manuscript. The Spanish National Library is home to one of the most extraordinary examples of illuminated manuscript production of Norman Sicily – the Messina Missal. Dating from the late twelfth century, this liturgical book was the result of the intense activity of artistic patronage of an Englishman, Richard Palmer. Appointed bishop of the Sicilian city in the second half of the century, Palmer set a painting workshop attached to his cathedral. The illuminated manuscripts produced there combine a clear Byzantine iconographic language with a myriad of elements imported from France, such as a large number of decorated initials. The most remarkable depiction contained in the Missal is that of the Theotokos (fol. 80r). Its appearance immediately recalls portative Byzantine icons of the Mother of God in South Italy and Byzantium and implies the intervention of an artist familiar with icon painting. The richness of this image is a clear proof of the prestige that Byzantine art enjoyed in the island after the Norman takeover. The production of the school of Messina under Richard Palmer could be considered a counterpart in the field of manuscript illumination of the court art of the Sicilian kings in Palermo and the impressive commissions for the cathedrals of Monreale and Cefalù. However, the ethnic composition of Palmer’s workshop has never been analyzed and therefore, we intend to shed light on the permanent presence of Greek-speaking artists in Norman Messina. The east of the island was the last stronghold of the Greeks and soon after the Norman conquest, the previous exchanges between the cities of this territory and Byzantium restarted again, mainly by way of trade. Palmer was not a Norman statesman, but a churchman and his love for religion and culture prevailed over the wars and struggles for power of the Sicilian kingdom in the central Mediterranean. On the other hand, the representation of the Theotokos can prove that Eastern devotional approaches to images were still common in the east of the island more than a century after the collapse of Byzantine rule. Local Norman lords repeatedly founded churches devoted to Greek saints and medieval Greek-speaking authors were widely copied in Sicilian scriptoria. The Madrid Missal and its Theotokos are doubtless the product of Western initiative but in a land culturally dominated by Byzantium. Westerners, such as Palmer and his circle, could have been immersed in this Hellenophile culture and therefore, naturally predisposed to perform prayers and rituals, in both public and private contexts, linked to ideas and practices of Greek origin, such as the concept of icon.

Keywords: history of art, byzantine art, manuscripts, norman sicily, messina, patronage, devotion, iconography

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428 Selective Separation of Amino Acids by Reactive Extraction with Di-(2-Ethylhexyl) Phosphoric Acid

Authors: Alexandra C. Blaga, Dan Caşcaval, Alexandra Tucaliuc, Madalina Poştaru, Anca I. Galaction

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Amino acids are valuable chemical products used in in human foods, in animal feed additives and in the pharmaceutical field. Recently, there has been a noticeable rise of amino acids utilization throughout the world to include their use as raw materials in the production of various industrial chemicals: oil gelating agents (amino acid-based surfactants) to recover effluent oil in seas and rivers and poly(amino acids), which are attracting attention for biodegradable plastics manufacture. The amino acids can be obtained by biosynthesis or from protein hydrolysis, but their separation from the obtained mixtures can be challenging. In the last decades there has been a continuous interest in developing processes that will improve the selectivity and yield of downstream processing steps. The liquid-liquid extraction of amino acids (dissociated at any pH-value of the aqueous solutions) is possible only by using the reactive extraction technique, mainly with extractants of organophosphoric acid derivatives, high molecular weight amines and crown-ethers. The purpose of this study was to analyse the separation of nine amino acids of acidic character (l-aspartic acid, l-glutamic acid), basic character (l-histidine, l-lysine, l-arginine) and neutral character (l-glycine, l-tryptophan, l-cysteine, l-alanine) by reactive extraction with di-(2-ethylhexyl)phosphoric acid (D2EHPA) dissolved in butyl acetate. The results showed that the separation yield is controlled by the pH value of the aqueous phase: the reactive extraction of amino acids with D2EHPA is possible only if the amino acids exist in aqueous solution in their cationic forms (pH of aqueous phase below the isoeletric point). The studies for individual amino acids indicated the possibility of selectively separate different groups of amino acids with similar acidic properties as a function of aqueous solution pH-value: the maximum yields are reached for a pH domain of 2–3, then strongly decreasing with the pH increase. Thus, for acidic and neutral amino acids, the extraction becomes impossible at the isolelectric point (pHi) and for basic amino acids at a pH value lower than pHi, as a result of the carboxylic group dissociation. From the results obtained for the separation from the mixture of the nine amino acids, at different pH, it can be observed that all amino acids are extracted with different yields, for a pH domain of 1.5–3. Over this interval, the extract contains only the amino acids with neutral and basic character. For pH 5–6, only the neutral amino acids are extracted and for pH > 6 the extraction becomes impossible. Using this technique, the total separation of the following amino acids groups has been performed: neutral amino acids at pH 5–5.5, basic amino acids and l-cysteine at pH 4–4.5, l-histidine at pH 3–3.5 and acidic amino acids at pH 2–2.5.

Keywords: amino acids, di-(2-ethylhexyl) phosphoric acid, reactive extraction, selective extraction

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427 Plant Microbiota of Coastal Halophyte Salicornia Ramossisima

Authors: Isabel N. Sierra-Garcia, Maria J. Ferreira, Sandro Figuereido, Newton Gomes, Helena Silva, Angela Cunha

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Plant-associated microbial communities are considered crucial in the adaptation of halophytes to coastal environments. The plant microbiota can be horizontally acquired from the environment or vertically transmitted from generation to generation via seeds. Recruiting of the microbial communities by the plant is affected by geographical location, soil source, host genotype, and cultivation practice. There is limited knowledge reported on the microbial communities in halophytes the influence of biotic and abiotic factors. In this work, the microbiota associated with the halophyte Salicornia ramosissima was investigated to determine whether the structure of bacterial communities is influenced by host genotype or soil source. For this purpose, two contrasting sites where S. ramosissima is established in the estuarine system of the Ria de Aveiro were investigated. One site corresponds to a natural salt marsh where S. ramosissima plants are present (wild plants), and the other site is a former salt pan that nowadays are subjected to intensive crop production of S. ramosissima (crop plants). Bacterial communities from the rhizosphere, seeds and root endosphere of S. ramossisima from both sites were investigated by sequencing bacterial 16S rRNA gene using the Illumina MiSeq platform. The analysis of the sequences showed that the three plant-associated compartments, rhizosphere, root endosphere, and seed endosphere, harbor distinct microbiomes. However, bacterial richness and diversity were higher in seeds of wild plants, followed by rhizosphere in both sites, while seeds in the crop site had the lowest diversity. Beta diversity measures indicated that bacterial communities in root endosphere and seeds were more similar in both wild and crop plants in contrast to rhizospheres that differed by local, indicating that the recruitment of the similar bacterial communities by the plant genotype is active in regard to the site. Moreover, bacterial communities from the root endosphere and rhizosphere were phylogenetically more similar in both sites, but the phylogenetic composition of seeds in wild and crop sites was distinct. These results indicate that cultivation practices affect the seed microbiome. However, minimal vertical transmission of bacteria from seeds to adult plants is expected. Seeds from the crop site showed higher abundances of Kushneria and Zunongwangia genera. Bacterial members of the classes Alphaprotebacteria and Bacteroidia were the most ubiquitous across sites and compartments and might encompass members of the core microbiome. These findings indicate that bacterial communities associated with S. ramosissima are more influenced by host genotype rather than local abiotic factors or cultivation practices. This study provides a better understanding of the composition of the plant microbiota in S. ramosissima , which is essential to predict the interactions between plant and associated microbial communities and their effects on plant health. This knowledge is useful to the manipulations of these microbial communities to enhance the health and productivity of this commercially important plant.

Keywords: halophytes, plant microbiome, Salicornia ramosissima, agriculture

Procedia PDF Downloads 143
426 Mental Illness, Dargahs and Healing: A Qualitative Exploration in a North Indian City

Authors: Reetinder Kaur, R. K. Pathak

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Mental health is recognised as an important global health concern. World Health Organisation in 2004 estimated that neuropsychiatric illnesses in India account for 10.8 percent of the global burden. The prevalence of serious mental illnesses is estimated as 6.5 percent by National Commission of Macroeconomics and Health in 2005. India spends only 0.06 percent of its health budget on mental health. One of the major problems that exist in Indian mental health care is the treatment gap due to scarcity of manpower, inadequate infrastructure and deficiencies in policy initiatives. As a result, traditional healing is a popular resource for mentally ill individuals and their families. The various traditional healing resources include faith healers, healers at temples and Dargahs. Chandigarh is a Union Territory located in North India. It has surplus manpower and infrastructure available for mental health care. Inspite of availability of mental health care services, mentally ill individuals and their families seek help from traditional healers at various Dargahs within or outside Chandigarh. For the present study, the data was collected from four dargahs. A total of thirty patients medically diagnosed with various mental illnesses, their family members who accompanied them and healers were part of this study. The aim of the study was to: Understand the interactions between healer, patient and family members during the course of treatment, understand explanations of mental illnesses and analyse the healing practices in context of culture. The interviews were conducted using an interview guide for the three sets of informants: Healers, patients and family members. The interview guide for healer focussed on the healing process, healer’s understanding of patient’s explanatory models, healer’s knowledge about mental illnesses and types of these illnesses cured by the healer. The interview guide for patients and family members focussed on their understanding of the symptoms, explanations for illness and help-seeking behaviour. The patients were observed over the weeks (every Thursday, the day of pir and healing) during their visits to the healer. Detailed discussions were made with the healer regarding the healing process and benefits of healing. The data was analysed thematically and the themes: The role of sacred, holistic healing, healer’s understanding of patient’s explanatory models of mental illness, the patient’s, and family’s understanding of mental illnesses, healer’s knowledge about mental illnesses, types of mental illnesses cured by the healer, bad dreams and their interpretation emerged. From the analysis of data, it was found that the healers concentrate their interventions in the social arena, ‘curing’ distressed patients by bringing significant changes in their social environment. It is suggested that in order to make the mental health care services effective in India, the collaboration between healers and psychiatrist is essential. However, certain specifications need to be made to make this kind of collaboration successful and beneficial for the stakeholders.

Keywords: Dargah, mental illness, traditional healing, policy

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425 Phage Display-Derived Vaccine Candidates for Control of Bovine Anaplasmosis

Authors: Itzel Amaro-Estrada, Eduardo Vergara-Rivera, Virginia Juarez-Flores, Mayra Cobaxin-Cardenas, Rosa Estela Quiroz, Jesus F. Preciado, Sergio Rodriguez-Camarillo

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Bovine anaplasmosis is an infectious, tick-borne disease caused mainly by Anaplasma marginale; typical signs include anemia, fever, abortion, weight loss, decreased milk production, jaundice, and potentially death. Sick bovine can recover when antibiotics are administered; however, it usually remains as carrier for life, being a risk of infection for susceptible cattle. Anaplasma marginale is an obligate intracellular Gram-negative bacterium with genetic composition highly diverse among geographical isolates. There are currently no vaccines fully effective against bovine anaplasmosis; therefore, the economic losses due to disease are present. Vaccine formulation became a hard task for several pathogens as Anaplasma marginale, but peptide-based vaccines are an interesting proposal way to induce specific responses. Phage-displayed peptide libraries have been proved one of the most powerful technologies for identifying specific ligands. Screening of these peptides libraries is also a tool for studying interactions between proteins or peptides. Thus, it has allowed the identification of ligands recognized by polyclonal antiserums, and it has been successful for the identification of relevant epitopes in chronic diseases and toxicological conditions. Protective immune response to bovine anaplasmosis includes high levels of immunoglobulins subclass G2 (IgG2) but not subclass IgG1. Therefore, IgG2 from the serum of protected bovine can be useful to identify ligands, which can be part of an immunogen for cattle. In this work, phage display random peptide library Ph.D. ™ -12 was incubating with IgG2 or blood sera of immunized bovines against A. marginale as targets. After three rounds of biopanning, several candidates were selected for additional analysis. Subsequently, their reactivity with sera immunized against A. marginale, as well as with positive and negative sera to A. marginale was evaluated by immunoassays. A collection of recognized peptides tested by ELISA was generated. More than three hundred phage-peptides were separately evaluated against molecules which were used during panning. At least ten different peptides sequences were determined from their nucleotide composition. In this approach, three phage-peptides were selected by their binding and affinity properties. In the case of the development of vaccines or diagnostic reagents, it is important to evaluate the immunogenic and antigenic properties of the peptides. Immunogenic in vitro and in vivo behavior of peptides will be assayed as synthetic and as phage-peptide for to determinate their vaccine potential. Acknowledgment: This work was supported by grant SEP-CONACYT 252577 given to I. Amaro-Estrada.

Keywords: bovine anaplasmosis, peptides, phage display, veterinary vaccines

Procedia PDF Downloads 125
424 Women Soldiers in the Israel Defence Forces: Changing Trends of Gender Equality and Military Service

Authors: Dipanwita Chakravortty

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Officially, the Israel Defence Forces (IDF) follows a policy of 'gender equality and partnership' which institutionalises norms regarding equal duty towards the nation. It reiterates the equality in unbiased opportunities and resources for Jewish men and women to participate in the military as equal citizens. At the same time, as a military institution, the IDF supports gender biases and crystallises the same through various interactions among women soldiers, male soldiers and the institution. These biases are expressed through various stages and processes in the military institution like biased training, discriminatory postings of women soldiers, lack of combat training and acceptance of sexual harassment. The gender-military debates in Israel is largely devoted to female emancipation and converting the militarised women’s experiences into mainstream debates. This critical scholarship, largely female-based and located in Israel, has been consistently critical of the structural policies of the IDF that have led to continued discriminatory practices against women soldiers. This has compelled the military to increase its intake of women soldiers and make its structural policies more gender-friendly. Nonetheless, the continued thriving of gender discrimination in the IDF resulted in scholars looking deep into the failure of these policies in bringing about a change. This article looks into two research objectives, firstly to analyse existing gender relations in the IDF which impact the practices and prejudices in the institution and secondly to look beyond the structural discrimination as part of the gender debates in the IDF. The proposed research uses the structural-functional model as a framework to study the discourses and norms emerging out of the interaction between gender and military as two distinct social institutions. Changing gender-military debates will be discussed in great detail to understanding the in-depth relation between the Israeli society and the military due to the conscription model. The main arguments of the paper deal with the functional aspect of the military service rather than the structural component of the institution. Traditional stereotypes of military institutions along with cultural notions of a female body restrict the complete integration of women soldiers despite favourable legislations and policies. These result in functional discriminations like uneven promotion, sexual violence, restructuring gender identities and creating militarised bodies. The existing prejudices encourage younger women recruits to choose from within the accepted pink-collared jobs in the military rather than ‘breaking the barriers.’ Some women recruits do try to explore new avenues and make a mark for themselves. Most of them face stiff discrimination but they accept it as part of military life. The cyclical logic behind structural norms leading to functional discrimination which then emphasises traditional stereotypes and hampers change in the institutional norms compels the IDF to continue to strive towards gender equality within the institution without practical realisation.

Keywords: women soldiers, Israel Defence Forces, gender-military debates, security studies

Procedia PDF Downloads 148
423 The Influence of Liberal Arts and Sciences Pedagogy and Covid Pandemic on Global Health Workforce Training in China: A Qualitative Study

Authors: Meifang Chen

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Background: As China increased its engagement in global health affairs and research, global Health (GH) emerged as a new discipline in China after 2010. Duke Kunshan University (DKU), as a member of the Chinese Consortium of Universities for Global Health, is the first university that experiments “Western-style” liberal arts and sciences (LAS) education pedagogy in GH undergraduate and postgraduate programs in China since 2014. The COVID-19 pandemic has brought significant disruption to education across the world. At the peak of the pandemic, 45 countries in the Europe and Central Asia regions closed their schools, affecting 185 million students. DKU, as many other universities and schools, was unprepared for this sudden abruptness and were forced to build emergency remote learning systems almost immediately. This qualitative study aims to gain a deeper understanding of 1) how Chinese students and parents embrace GH training in the liberal arts and sciences education context, and 2) how the COVID pandemic influences the students’ learning experience as well as affects students and parents’ perceptions of GH-related study and career development in China. Methods: students and parents at DKU were invited and recruited for open-ended, semi-structured interviews during Sept 2021-Mar 2022. Open coding procedures and thematic content analysis were conducted using Nvivo 12 software. Results: A total of 18 students and 36 parents were interviewed. Both students and parents were fond of delivering GH education using the liberal arts and sciences pedagogy. Strengths of LAS included focusing on whole person development, allowing personal enrichment, tailoring curriculum to individual’s interest, providing well-rounded knowledge through interdisciplinary learning, and increasing self-study capacity and adaptability. Limitations of LAS included less time to dive deep into disciplines. There was a significant improvement in independence, creativity, problem solving, and team coordinating capabilities among the students. The impact of the COVID pandemic on GH learning experience included less domestic and abroad fieldwork opportunities, less in-person interactions (especially with foreign students and faculty), less timely support, less lab experience, and coordination challenges due to time-zone difference. The COVID pandemic increased the public’s awareness of the importance of GH and acceptance of GH as a career path. More job and postgraduate program opportunities were expected in near future. However, some parents expressed concerns about GH-related employment opportunities in China. Conclusion: The application of the liberal arts and science education pedagogy in GH training were well-received by the Chinese students and parents. Although global pandemic like COVID disrupted GH learning in many ways, most Chinese students and parents held optimistic attitudes toward GH study and career development.

Keywords: COVID, global health, liberal arts and sciences pedagogy, China

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422 Examining College Students’ Attitudes toward Diversity Environments in a Physical Activity Course

Authors: Young Ik Suh, Sanghak Lee, Tae Wook Chung

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In recent year, cultural diversity has acquired increasing attentions in our society due to the cultural pluralism and globalization. With the emphasis of diversity in our society, higher education has played a significant role in preparing people to be successful in a diverse world. A number of colleges and universities provide various diversity-related courses that enhance students to recognize the importance of diversity and multiculturalism. However, little research has been conducted with diversity environments in physical activity and sports-related courses to appreciate students’ attitudes toward multiculturalism. Physical activity courses can be regarded as an essential and complementary part of general education. As well, playing and watching certain sports plays a critical role to foster mutual understanding between different races and to help social integration for minority communities. Therefore, it is expected that the appropriate diverse environments in physical activity courses may have a positive impact to the understandings of different cultures and races. The primary purpose of this study is to examine attitudes toward cultural diversity in a physical activity course among undergraduate students. In building on the scholarly foundation in this area, this study applies the established survey scale (e.g., Pluralism and Diversity Attitude Assessment [PADAA]) developed by Stanley (1996) and previous literature related to cultural diversity. The PADAA includes 19 questions. The following two research hypotheses were proposed. H1: Students who take a diversity-related physical course (i.e., Taekwondo) will provide positive attitude changes toward their cultural diversity. H2: Students who take a general physical activity course (i.e., Weight Training) will provide no significant attitude changes toward their cultural diversity. To test the research hypotheses, subjects will be selected from the both Taekwondo and Weight Training class at University of West Georgia. In the Taekwondo class, students will learn the history, meaning, basic terminology, and physical skills, which is a Korean martial art and the national sport of Korea. In the Weight Training class, students will not be exposed to any cultural diversity topics. Regarding data analysis, Doubly Multivariate Analysis of Covariance (Doubly MANCOVA), 2 (time period: pre and after) X 2 (diversity-related content exposure: Taekwondo and Weight Training), will be conducted on attitudes toward the cultural diversity with control variables such as gender and age. The findings of this study will add to the body of literature in cultural diversity because this will be the first known attempt to explain the college students’ attitudes toward cultural diversity in a physical activity courses. The expected results will state that the physical activity course focusing on diversity issues will have a positive impact on college students’ attitude toward cultural diversity. This finding will indicate that Universities need to create diverse programs (e.g., study abroad, exchange program, second language courses) and environments so that students can have positive interactions with other groups of races and different cultures. It is also expected that the positive perceptions and attitudes toward cultural diversity will break down cultural barriers and make students be ready for meeting several challenges in a multicultural and global society.

Keywords: cultural diversity, physical activity course, attitude, Taekwondo

Procedia PDF Downloads 255
421 Preparation of Activated Carbon From Waste Feedstock: Activation Variables Optimization and Influence

Authors: Oluwagbemi Victor Aladeokin

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In the last decade, the global peanut cultivation has seen increased demand, which is attributed to their health benefits, rising to ~ 41.4 MMT in 2019/2020. Peanut and other nutshells are considered as waste in various parts of the world and are usually used for their fuel value. However, this agricultural by-product can be converted to a higher value product such as activated carbon. For many years, due to the highly porous structure of activated carbon, it has been widely and effectively used as an adsorbent in the purification and separation of gases and liquids. Those used for commercial purposes are primarily made from a range of precursors such as wood, coconut shell, coal, bones, etc. However, due to difficulty in regeneration and high cost, various agricultural residues such as rice husk, corn stalks, apricot stones, almond shells, coffee beans, etc, have been explored to produce activated carbons. In the present study, the potential of peanut shells as precursors in the production of activated carbon and their adsorption capacity is investigated. Usually, precursors used to produce activated carbon have carbon content above 45 %. A typical raw peanut shell has 42 wt.% carbon content. To increase the yield, this study has employed chemical activation method using zinc chloride. Zinc chloride is well known for its effectiveness in increasing porosity of porous carbonaceous materials. In chemical activation, activation temperature and impregnation ratio are parameters commonly reported to be the most significant, however, this study has also studied the influence of activation time on the development of activated carbon from peanut shells. Activated carbons are applied for different purposes, however, as the application of activated carbon becomes more specific, an understanding of the influence of activation variables to have a better control of the quality of the final product becomes paramount. A traditional approach to experimentally investigate the influence of the activation parameters, involves varying each parameter at a time. However, a more efficient way to reduce the number of experimental runs is to apply design of experiment. One of the objectives of this study is to optimize the activation variables. Thus, this work has employed response surface methodology of design of experiment to study the interactions between the activation parameters and consequently optimize the activation parameters (temperature, impregnation ratio, and activation time). The optimum activation conditions found were 485 °C, 15 min and 1.7, temperature, activation time, and impregnation ratio respectively. The optimum conditions resulted in an activated carbon with relatively high surface area ca. 1700 m2/g, 47 % yield, relatively high density, low ash, and high fixed carbon content. Impregnation ratio and temperature were found to mostly influence the final characteristics of the produced activated carbon from peanut shells. The results of this study, using response surface methodology technique, have revealed the potential and the most significant parameters that influence the chemical activation process, of peanut shells to produce activated carbon which can find its use in both liquid and gas phase adsorption applications.

Keywords: chemical activation, fixed carbon, impregnation ratio, optimum, surface area

Procedia PDF Downloads 124
420 Active Development of Tacit Knowledge: Knowledge Management, High Impact Practices and Experiential Learning

Authors: John Zanetich

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Due to their positive associations with student learning and retention, certain undergraduate opportunities are designated ‘high-impact.’ High-Impact Practices (HIPs) such as, learning communities, community based projects, research, internships, study abroad and culminating senior experience, share several traits bin common: they demand considerable time and effort, learning occurs outside of the classroom, and they require meaningful interactions between faculty and students, they encourage collaboration with diverse others, and they provide frequent and substantive feedback. As a result of experiential learning in these practices, participation in these practices can be life changing. High impact learning helps individuals locate tacit knowledge, and build mental models that support the accumulation of knowledge. On-going learning from experience and knowledge conversion provides the individual with a way to implicitly organize knowledge and share knowledge over a lifetime. Knowledge conversion is a knowledge management component which focuses on the explication of the tacit knowledge that exists in the minds of students and that knowledge which is embedded in the process and relationships of the classroom educational experience. Knowledge conversion is required when working with tacit knowledge and the demand for a learner to align deeply held beliefs with the cognitive dissonance created by new information. Knowledge conversion and tacit knowledge result from the fact that an individual's way of knowing, that is, their core belief structure, is considered generalized and tacit instead of explicit and specific. As a phenomenon, tacit knowledge is not readily available to the learner for explicit description unless evoked by an external source. The development of knowledge–related capabilities such as Aggressive Development of Tacit Knowledge (ADTK) can be used in experiential educational programs to enhance knowledge, foster behavioral change, improve decision making, and overall performance. ADTK allows the student in HIPs to use their existing knowledge in a way that allows them to evaluate and make any necessary modifications to their core construct of reality in order to amalgamate new information. Based on the Lewin/Schein Change Theory, the learner will reach for tacit knowledge as a stabilizing mechanism when they are challenged by new information that puts them slightly off balance. As in word association drills, the important concept is the first thought. The reactionary outpouring to an experience is the programmed or tacit memory and knowledge of their core belief structure. ADTK is a way to help teachers design their own methods and activities to unfreeze, create new learning, and then refreeze the core constructs upon which future learning in a subject area is built. This paper will explore the use of ADTK as a technique for knowledge conversion in the classroom in general and in HIP programs specifically. It will focus on knowledge conversion in curriculum development and propose the use of one-time educational experiences, multi-session experiences and sequential program experiences focusing on tacit knowledge in educational programs.

Keywords: tacit knowledge, knowledge management, college programs, experiential learning

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419 Enhancement Effect of Superparamagnetic Iron Oxide Nanoparticle-Based MRI Contrast Agent at Different Concentrations and Magnetic Field Strengths

Authors: Bimali Sanjeevani Weerakoon, Toshiaki Osuga, Takehisa Konishi

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Magnetic Resonance Imaging Contrast Agents (MRI-CM) are significant in the clinical and biological imaging as they have the ability to alter the normal tissue contrast, thereby affecting the signal intensity to enhance the visibility and detectability of images. Superparamagnetic Iron Oxide (SPIO) nanoparticles, coated with dextran or carboxydextran are currently available for clinical MR imaging of the liver. Most SPIO contrast agents are T2 shortening agents and Resovist (Ferucarbotran) is one of a clinically tested, organ-specific, SPIO agent which has a low molecular carboxydextran coating. The enhancement effect of Resovist depends on its relaxivity which in turn depends on factors like magnetic field strength, concentrations, nanoparticle properties, pH and temperature. Therefore, this study was conducted to investigate the impact of field strength and different contrast concentrations on enhancement effects of Resovist. The study explored the MRI signal intensity of Resovist in the physiological range of plasma from T2-weighted spin echo sequence at three magnetic field strengths: 0.47 T (r1=15, r2=101), 1.5 T (r1=7.4, r2=95), and 3 T (r1=3.3, r2=160) and the range of contrast concentrations by a mathematical simulation. Relaxivities of r1 and r2 (L mmol-1 Sec-1) were obtained from a previous study and the selected concentrations were 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 2.0, and 3.0 mmol/L. T2-weighted images were simulated using TR/TE ratio as 2000 ms /100 ms. According to the reference literature, with increasing magnetic field strengths, the r1 relaxivity tends to decrease while the r2 did not show any systematic relationship with the selected field strengths. In parallel, this study results revealed that the signal intensity of Resovist at lower concentrations tends to increase than the higher concentrations. The highest reported signal intensity was observed in the low field strength of 0.47 T. The maximum signal intensities for 0.47 T, 1.5 T and 3 T were found at the concentration levels of 0.05, 0.06 and 0.05 mmol/L, respectively. Furthermore, it was revealed that, the concentrations higher than the above, the signal intensity was decreased exponentially. An inverse relationship can be found between the field strength and T2 relaxation time, whereas, the field strength was increased, T2 relaxation time was decreased accordingly. However, resulted T2 relaxation time was not significantly different between 0.47 T and 1.5 T in this study. Moreover, a linear correlation of transverse relaxation rates (1/T2, s–1) with the concentrations of Resovist can be observed. According to these results, it can conclude that the concentration of SPIO nanoparticle contrast agents and the field strengths of MRI are two important parameters which can affect the signal intensity of T2-weighted SE sequence. Therefore, when MR imaging those two parameters should be considered prudently.

Keywords: Concentration, resovist, field strength, relaxivity, signal intensity

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418 Contextual Toxicity Detection with Data Augmentation

Authors: Julia Ive, Lucia Specia

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Understanding and detecting toxicity is an important problem to support safer human interactions online. Our work focuses on the important problem of contextual toxicity detection, where automated classifiers are tasked with determining whether a short textual segment (usually a sentence) is toxic within its conversational context. We use “toxicity” as an umbrella term to denote a number of variants commonly named in the literature, including hate, abuse, offence, among others. Detecting toxicity in context is a non-trivial problem and has been addressed by very few previous studies. These previous studies have analysed the influence of conversational context in human perception of toxicity in controlled experiments and concluded that humans rarely change their judgements in the presence of context. They have also evaluated contextual detection models based on state-of-the-art Deep Learning and Natural Language Processing (NLP) techniques. Counterintuitively, they reached the general conclusion that computational models tend to suffer performance degradation in the presence of context. We challenge these empirical observations by devising better contextual predictive models that also rely on NLP data augmentation techniques to create larger and better data. In our study, we start by further analysing the human perception of toxicity in conversational data (i.e., tweets), in the absence versus presence of context, in this case, previous tweets in the same conversational thread. We observed that the conclusions of previous work on human perception are mainly due to data issues: The contextual data available does not provide sufficient evidence that context is indeed important (even for humans). The data problem is common in current toxicity datasets: cases labelled as toxic are either obviously toxic (i.e., overt toxicity with swear, racist, etc. words), and thus context does is not needed for a decision, or are ambiguous, vague or unclear even in the presence of context; in addition, the data contains labeling inconsistencies. To address this problem, we propose to automatically generate contextual samples where toxicity is not obvious (i.e., covert cases) without context or where different contexts can lead to different toxicity judgements for the same tweet. We generate toxic and non-toxic utterances conditioned on the context or on target tweets using a range of techniques for controlled text generation(e.g., Generative Adversarial Networks and steering techniques). On the contextual detection models, we posit that their poor performance is due to limitations on both of the data they are trained on (same problems stated above) and the architectures they use, which are not able to leverage context in effective ways. To improve on that, we propose text classification architectures that take the hierarchy of conversational utterances into account. In experiments benchmarking ours against previous models on existing and automatically generated data, we show that both data and architectural choices are very important. Our model achieves substantial performance improvements as compared to the baselines that are non-contextual or contextual but agnostic of the conversation structure.

Keywords: contextual toxicity detection, data augmentation, hierarchical text classification models, natural language processing

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417 Biocontrol Potential of Trichoderma longibrachiatum as an Entomopathogenic Fungi against Bemisia tabaci

Authors: Waheed Anwar, Kiran Nawaz, Muhammad Saleem Haider, Ahmad Ali Shahid, Sehrish Iftikhar

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The whitefly, Bemisia tabaci (Gennadius), is a complex insect species, including many cryptic species or biotypes. Whitefly causes damage to many ornamental and horticultural crops through directly feeding on phloem sap, resulting in sooty mould and critically decreases the rate of photosynthesis of many host plants. Biological control has emerged as one of the most important methods for the management of soil-borne plant pathogens. Among the natural enemies of insects different entomopathogenic fungi are mostly used as biological control of the pest. The purpose of this research was to find indigenous insect-associated fungi and their virulence against Bemisia tabaci. A detailed survey of cotton fields in sample collection was conducted during July and August 2013 from the central mixed zone of Punjab, Pakistan. For the isolation of T. longibrachiatum, sabouraud dextrose peptone yeast extract agar (SDAY) media was used and morphological characterization of isolated T. longibrachiatum was studied using different dichotomous keys. Molecular Identification of the pathogen was confirmed by amplifying the internal transcribed spacer region. Blastn analysis showed 100% homology with already reported sequences on the database. For these bioassays, two conidial concentrations 4 × 108/mL & 4 × 104/mL of T. longibrachiatum was sprayed in clip cages for nymph and adult B. tabaci respectively under controlled environmental conditions. The pathogenicity of T. longibrachiatum was tested on nymph and adult whitefly to check mortality. Mortality of B. tabaci at nymphal and adult stages were observed after 24-hour intervals. Percentage mortality of nymphs treated with 4 x 104/mL conidia of T. longibrachiatum was 20, 24, 36 and 40% after 48, 72, 96, 72, 96, 120 and 144 hours respectively. However, no considerable difference was recorded in percentage mortality of whitefly after 120 and 144 hours. There were great variations after 24, 48, 72 and 96 hours in the rate of mortality. The efficacy of T. longibrachiatum as entomopathogenic fungi was evaluated in adult and nymphal stages of whitefly. Trichoderma longibrachiatum showed maximum activity on nymphal stages of whitefly as compared to adult stages. The percentage of conidial germination was also recorded on the outer surface of adult and nymphal stages of B. tabaci. The present findings indicated that T. longibrachiatum is an entomopathogenic fungus against B. tabaci and many species of Trichoderma were already reported as an antagonistc organism against a wide range of bacterial and fungal pathogens.

Keywords: efficacy, Trichoderma, virulence, bioassay

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416 Vortex Control by a Downstream Splitter Plate in Psudoplastic Fluid Flow

Authors: Sudipto Sarkar, Anamika Paul

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Pseudoplastic (n<1, n is the power index) fluids have great importance in food, pharmaceutical and chemical process industries which require a lot of attention. Unfortunately, due to its complex flow behavior inadequate research works can be found even in laminar flow regime. A practical problem is solved in the present research work by numerical simulation where we tried to control the vortex shedding from a square cylinder using a horizontal splitter plate placed at the downstream flow region. The position of the plate is at the centerline of the cylinder with varying distance from the cylinder to calculate the critical gap-ratio. If the plate is placed inside this critical gap, the vortex shedding from the cylinder suppressed completely. The Reynolds number considered here is in unsteady laminar vortex shedding regime, Re = 100 (Re = U∞a/ν, where U∞ is the free-stream velocity of the flow, a is the side of the cylinder and ν is the maximum value of kinematic viscosity of the fluid). Flow behavior has been studied for three different gap-ratios (G/a = 2, 2.25 and 2.5, where G is the gap between cylinder and plate) and for a fluid with three different flow behavior indices (n =1, 0.8 and 0.5). The flow domain is constructed using Gambit 2.2.30 and this software is also used to generate the mesh and to impose the boundary conditions. For G/a = 2, the domain size is considered as 37.5a × 16a with 316 × 208 grid points in the streamwise and flow-normal directions respectively after a thorough grid independent study. Fine and equal grid spacing is used close to the geometry to capture the vortices shed from the cylinder and the boundary layer developed over the flat plate. Away from the geometry meshes are unequal in size and stretched out. For other gap-ratios, proportionate domain size and total grid points are used with similar kind of mesh distribution. Velocity inlet (u = U∞), pressure outlet (Neumann condition), symmetry (free-slip boundary condition) at upper and lower domain boundary conditions are used for the simulation. Wall boundary condition (u = v = 0) is considered both on the cylinder and the splitter plate surfaces. Discretized forms of fully conservative 2-D unsteady Navier Stokes equations are then solved by Ansys Fluent 14.5. SIMPLE algorithm written in finite volume method is selected for this purpose which is a default solver inculcate in Fluent. The results obtained for Newtonian fluid flow agree well with previous works supporting Fluent’s usefulness in academic research. A thorough analysis of instantaneous and time-averaged flow fields are depicted both for Newtonian and pseudoplastic fluid flow. It has been observed that as the value of n reduces the stretching of shear layers also reduce and these layers try to roll up before the plate. For flow with high pseudoplasticity (n = 0.5) the nature of vortex shedding changes and the value of critical gap-ratio reduces. These are the remarkable findings for laminar periodic vortex shedding regime in pseudoplastic flow environment.

Keywords: CFD, pseudoplastic fluid flow, wake-boundary layer interactions, critical gap-ratio

Procedia PDF Downloads 100