Search results for: cell death
1639 Expression Profiling of Chlorophyll Biosynthesis Pathways in Chlorophyll B-Lacking Mutants of Rice (Oryza sativa L.)
Authors: Khiem M. Nguyen, Ming C. Yang
Abstract:
Chloroplast pigments are extremely important during photosynthesis since they play essential roles in light absorption and energy transfer. Therefore, understanding the efficiency of chlorophyll (Chl) biosynthesis could facilitate enhancement in photo-assimilates accumulation, and ultimately, in crop yield. The Chl-deficient mutants have been used extensively to study the Chl biosynthetic pathways and the biogenesis of the photosynthetic apparatus. Rice (Oryza sativa L.) is one of the most leading food crops, serving as staple food for many parts of the world. To author’s best knowledge, Chl b–lacking rice has been found; however the molecular mechanism of Chl biosynthesis still remains unclear compared to wild-type rice. In this study, the ultrastructure analysis, photosynthetic properties, and transcriptome profile of wild-type rice (Norin No.8, N8) and its Chl b-lacking mutant (Chlorina 1, C1) were examined. The finding concluded that total Chl content and Chl b content in the C1 leaves were strongly reduced compared to N8 leaves, suggesting that reduction in the total Chl content contributes to leaf color variation at the physiological level. Plastid ultrastructure of C1 possessed abnormal thylakoid membranes with loss of starch granule, large number of vesicles, and numerous plastoglobuli. The C1 rice also exhibited thinner stacked grana, which was caused by a reduction in the number of thylakoid membranes per granum. Thus, the different Chl a/b ratio of C1 may reflect the abnormal plastid development and function. Transcriptional analysis identified 23 differentially expressed genes (DEGs) and 671 transcription factors (TFs) that were involved in Chl metabolism, chloroplast development, cell division, and photosynthesis. The transcriptome profile and DEGs revealed that the gene encoding PsbR (PSII core protein) was down-regulated, therefore suggesting that the lower in light-harvesting complex proteins are responsible for the lower photosynthetic capacity in C1. In addition, expression level of cell division protein (FtsZ) genes were significantly reduced in C1, causing chloroplast division defect. A total of 19 DEGs were identified based on KEGG pathway assignment involving Chl biosynthesis pathway. Among these DEGs, the GluTR gene was down-regulated, whereas the UROD, CPOX, and MgCH genes were up-regulated. Observation through qPCR suggested that later stages of Chl biosynthesis were enhanced in C1, whereas the early stages were inhibited. Plastid structure analysis together with transcriptomic analysis suggested that the Chl a/b ratio was amplified both by the reduction in Chl contents accumulation, owning to abnormal chloroplast development, and by the enhanced conversion of Chl b to Chl a. Moreover, the results indicated the same Chl-cycle pattern in the wild-type and C1 rice, indicating another Chl b degradation pathway. Furthermore, the results demonstrated that normal grana stacking, along with the absence of Chl b and greatly reduced levels of Chl a in C1, provide evidence to support the conclusion that other factors along with LHCII proteins are involved in grana stacking. The findings of this study provide insight into the molecular mechanisms that underlie different Chl a/b ratios in rice.Keywords: Chl-deficient mutant, grana stacked, photosynthesis, RNA-Seq, transcriptomic analysis
Procedia PDF Downloads 1301638 Legal Judgment Prediction through Indictments via Data Visualization in Chinese
Authors: Kuo-Chun Chien, Chia-Hui Chang, Ren-Der Sun
Abstract:
Legal Judgment Prediction (LJP) is a subtask for legal AI. Its main purpose is to use the facts of a case to predict the judgment result. In Taiwan's criminal procedure, when prosecutors complete the investigation of the case, they will decide whether to prosecute the suspect and which article of criminal law should be used based on the facts and evidence of the case. In this study, we collected 305,240 indictments from the public inquiry system of the procuratorate of the Ministry of Justice, which included 169 charges and 317 articles from 21 laws. We take the crime facts in the indictments as the main input to jointly learn the prediction model for law source, article, and charge simultaneously based on the pre-trained Bert model. For single article cases where the frequency of the charge and article are greater than 50, the prediction performance of law sources, articles, and charges reach 97.66, 92.22, and 60.52 macro-f1, respectively. To understand the big performance gap between articles and charges, we used a bipartite graph to visualize the relationship between the articles and charges, and found that the reason for the poor prediction performance was actually due to the wording precision. Some charges use the simplest words, while others may include the perpetrator or the result to make the charges more specific. For example, Article 284 of the Criminal Law may be indicted as “negligent injury”, "negligent death”, "business injury", "driving business injury", or "non-driving business injury". As another example, Article 10 of the Drug Hazard Control Regulations can be charged as “Drug Control Regulations” or “Drug Hazard Control Regulations”. In order to solve the above problems and more accurately predict the article and charge, we plan to include the article content or charge names in the input, and use the sentence-pair classification method for question-answer problems in the BERT model to improve the performance. We will also consider a sequence-to-sequence approach to charge prediction.Keywords: legal judgment prediction, deep learning, natural language processing, BERT, data visualization
Procedia PDF Downloads 1251637 Importance of Assessing Racial Trauma after George Floyd in Children of Color in Schools
Authors: Gabriela Macera DiFilippo
Abstract:
The world watched in disbelief as George Floyd was killed by a policeman. The images from the scene were made more memorable by Mr. Floyd’s pleas and cries for his mother. In the aftermath of this tragedy, the Black Lives Matter movement gained momentum. Weeks and months after the protests, global interest in learning about tackling systemic racism erupted. One must wonder how school children of color viewed and processed this trauma. This study will examine the kinds of trauma experienced by children of color and the opportunity for school mental health providers to support these children. This study used literature searches that were previously conducted for proven and practical assessment methods that can help deal with racial trauma for children. As part of the assessment, trauma symptoms experienced by children of color were summarized and characterized in a non-imperial manner. The research was also will be done in practical ways to make adequate and effective mental health services available in schools and lessen the stigma. This research study found that there is a need to provide an analysis of the ongoing racial trauma of children of color after the death of George Floyd. Impactful and appropriate assessment methods, such as surveys, were presented to all school professionals. Lastly, this paper attempted to provide mental health professionals with the tools to screen and provide guidance based on unequivocal, unbiased methods for helping these children. There is a need for both schools and community leaders to ensure that every child has access to mental health care and is being assessed for their overall well-being. There is a need to educate the communities about racial trauma and its impact on individuals, especially children. School mental health professionals are encouraged to offer and educate schools and communities about racial trauma awareness, its importance, and ways to cope with it in different settings. The delivery of these informed services should focus on behavioral health and must be sensitive to children of color and different ways of self-care.Keywords: trauma, children, black psychology, students
Procedia PDF Downloads 641636 Numerical Modeling of Phase Change Materials Walls under Reunion Island's Tropical Weather
Authors: Lionel Trovalet, Lisa Liu, Dimitri Bigot, Nadia Hammami, Jean-Pierre Habas, Bruno Malet-Damour
Abstract:
The MCP-iBAT1 project is carried out to study the behavior of Phase Change Materials (PCM) integrated in building envelopes in a tropical environment. Through the phase transitions (melting and freezing) of the material, thermal energy can be absorbed or released. This process enables the regulation of indoor temperatures and the improvement of thermal comfort for the occupants. Most of the commercially available PCMs are more suitable to temperate climates than to tropical climates. The case of Reunion Island is noteworthy as there are multiple micro-climates. This leads to our key question: developing one or multiple bio-based PCMs that cover the thermal needs of the different locations of the island. The present paper focuses on the numerical approach to select the PCM properties relevant to tropical areas. Numerical simulations have been carried out with two softwares: EnergyPlusTM and Isolab. The latter has been developed in the laboratory, with the implicit Finite Difference Method, in order to evaluate different physical models. Both are Thermal Dynamic Simulation (TDS) softwares that predict the building’s thermal behavior with one-dimensional heat transfers. The parameters used in this study are the construction’s characteristics (dimensions and materials) and the environment’s description (meteorological data and building surroundings). The building is modeled in accordance with the experimental setup. It is divided into two rooms, cells A and B, with same dimensions. Cell A is the reference, while in cell B, a layer of commercial PCM (Thermo Confort of MCI Technologies) has been applied to the inner surface of the North wall. Sensors are installed in each room to retrieve temperatures, heat flows, and humidity rates. The collected data are used for the comparison with the numerical results. Our strategy is to implement two similar buildings at different altitudes (Saint-Pierre: 70m and Le Tampon: 520m) to measure different temperature ranges. Therefore, we are able to collect data for various seasons during a condensed time period. The following methodology is used to validate the numerical models: calibration of the thermal and PCM models in EnergyPlusTM and Isolab based on experimental measures, then numerical testing with a sensitivity analysis of the parameters to reach the targeted indoor temperatures. The calibration relies on the past ten months’ measures (from September 2020 to June 2021), with a focus on one-week study on November (beginning of summer) when the effect of PCM on inner surface temperatures is more visible. A first simulation with the PCM model of EnergyPlus gave results approaching the measurements with a mean error of 5%. The studied property in this paper is the melting temperature of the PCM. By determining the representative temperature of winter, summer and inter-seasons with past annual’s weather data, it is possible to build a numerical model of multi-layered PCM. Hence, the combined properties of the materials will provide an optimal scenario for the application on PCM in tropical areas. Future works will focus on the development of bio-based PCMs with the selected properties followed by experimental and numerical validation of the materials. 1Materiaux ´ a Changement de Phase, une innovation pour le B ` ati TropicalKeywords: energyplus, multi-layer of PCM, phase changing materials, tropical area
Procedia PDF Downloads 1001635 Foucault and the Archaeology of Transhumanism
Authors: Michel Foucault, Friedrich Nietzsche, Max More, Natasha Vita-More, Francesca Ferrando
Abstract:
During the early part of his intellectual and academic career (1950s and 1960s), Michel Foucault developed an interest for what we can call the ‘anthropological question’, or how our modernity deals with human nature from an epistemological standpoint. The great originality of Foucault’s thought here lies in the fact that he approaches this question not from the perspective of this ‘sovereign subject’ (that has characterized the History of Western thought) he wishes to disclose and ‘denounce’, but rather at the level of discourses and the way they constitute who we are, so to speak. This led him, in turn, to formulate a series of though-provoking statements during his so-called ‘archaeological period’ of the 1960s concerning what we call ‘man’ in the West, such as that he is an ‘invention of recent date’ (as a proper object of concern and reflection), and, perhaps more importantly, that he might disappear in the near future, ‘like a face drawn in sand at the edge of the sea’. Foucault is following on the footsteps of Nietzsche in that regard, who had famously announced in the 19th ce. the ‘death of God’ and the need for the future generations to surpass (so to speak) the traditional ‘Christian-centred’ Western conception of the human. While Foucault exposed such insights more than half a century ago, they appear to be more actual than ever today with the development and rise in popularity of intellectual movements such as Transhumanism and Posthumanism, which seek to question and propose an alternative to the concepts of ‘man’ or ‘human nature’ in our culture. They rely for that on the same assumption as Foucault and Nietzsche that those concepts (and the meaning we attribute to them) have become ‘obsolete’ as it is and thus must be overcome (at a conceptual, but also a more practical level). Hence, those movements not only echo the important Foucauldian reflection of the 1950s and 1960s on the ‘anthropological question’ but seem to have been literally announced by it, so to speak. The aim of this paper will therefore be to show the relevance of Foucault (and in particular his archaeological method) in understanding the nature of Transhumanism (and Posthumanism), for instance, by analysing and assessing it as a form of discourse that is literally reshaping the way we understand ourselves as human beings in our (post)modern age, drawing for that on a number of key texts including from the early productions of Foucault.Keywords: foucault, nietzsche, archaeology, transhumanism, posthumanism
Procedia PDF Downloads 731634 Impact of Marangoni Stress and Mobile Surface Charge on Electrokinetics of Ionic Liquids Over Hydrophobic Surfaces
Authors: Somnath Bhattacharyya
Abstract:
The mobile adsorbed surface charge on hydrophobic surfaces can modify the velocity slip condition as well as create a Marangoni stress at the interface. The functionalized hydrophobic walls of micro/nanopores, e.g., graphene nanochannels, may possess physio-sorbed ions. The lateral mobility of the physisorbed absorbed ions creates a friction force as well as an electric force, leading to a modification in the velocity slip condition at the hydrophobic surface. In addition, the non-uniform distribution of these surface ions creates a surface tension gradient, leading to a Marangoni stress. The impact of the mobile surface charge on streaming potential and electrochemical energy conversion efficiency in a pressure-driven flow of ionized liquid through the nanopore is addressed. Also, enhanced electro-osmotic flow through the hydrophobic nanochannel is also analyzed. The mean-filed electrokinetic model is modified to take into account the short-range non-electrostatic steric interactions and the long-range Coulomb correlations. The steric interaction is modeled by considering the ions as charged hard spheres of finite radius suspended in the electrolyte medium. The electrochemical potential is modified by including the volume exclusion effect, which is modeled based on the BMCSL equation of state. The electrostatic correlation is accounted for in the ionic self-energy. The extremal of the self-energy leads to a fourth-order Poisson equation for the electric field. The ion transport is governed by the modified Nernst-Planck equation, which includes the ion steric interactions; born force arises due to the spatial variation of the dielectric permittivity and the dielectrophoretic force on the hydrated ions. This ion transport equation is coupled with the Navier-Stokes equation describing the flow of the ionized fluid and the 3fourth-order Poisson equation for the electric field. We numerically solve the coupled set of nonlinear governing equations along with the prescribed boundary conditions by adopting a control volume approach over a staggered grid arrangement. In the staggered grid arrangements, velocity components are stored on the midpoint of the cell faces to which they are normal, whereas the remaining scalar variables are stored at the center of each cell. The convection and electromigration terms are discretized at each interface of the control volumes using the total variation diminishing (TVD) approach to capture the strong convection resulting from the highly enhanced fluid flow due to the modified model. In order to link pressure to the continuity equation, we adopt a pressure correction-based iterative SIMPLE (Semi-Implicit Method for Pressure-Linked Equations) algorithm, in which the discretized continuity equation is converted to a Poisson equation involving pressure correction terms. Our results show that the physisorbed ions on a hydrophobic surface create an enhanced slip velocity when streaming potential, which enhances the convection current. However, the electroosmotic flow attenuates due to the mobile surface ions.Keywords: microfluidics, electroosmosis, streaming potential, electrostatic correlation, finite sized ions
Procedia PDF Downloads 761633 Magnesium Nanoparticles for Photothermal Therapy
Authors: E. Locatelli, I. Monaco, R. C. Martin, Y. Li, R. Pini, M. Chiariello, M. Comes Franchini
Abstract:
Despite the many advantages of application of nanomaterials in the field of nanomedicine, increasing concerns have been expressed on their potential adverse effects on human health. There is urgency for novel green strategies toward novel materials with enhanced biocompatibility using safe reagents. Photothermal ablation therapy, which exploits localized heat increase of a few degrees to kill cancer cells, has appeared recently as a non-invasive and highly efficient therapy against various cancer types; anyway new agents able to generate hyperthermia when irradiated are needed and must have precise biocompatibility in order to avoid damage to healthy tissues and prevent toxicity. Recently, there has been increasing interest in magnesium as a biomaterial: it is the fourth most abundant cation in the human body, and it is essential for human metabolism. However magnesium nanoparticles (Mg NPs) have had limited diffusion due to the high reduction potential of magnesium cations, which makes NPs synthesis challenging. Herein, we report the synthesis of Mg NPs and their surface functionalization for the obtainment of a stable and biocompatible nanomaterial suitable for photothermal ablation therapy against cancer. We synthesized the Mg crystals by reducing MgCl2 with metallic lithium and exploiting naphthalene as an electron carrier: the lithium–naphthalene complex acts as the real reducing agent. Firstly, the nanocrystal particles were coated with the ligand 12-ethoxy ester dodecanehydroxamic acid, and then entrapped into water-dispersible polymeric micelles (PMs) made of the FDA-approved PLGA-b-PEG-COOH copolymer using the oil-in-water emulsion technique. Lately, we developed a more straightforward methodology by introducing chitosan, a highly biocompatible natural product, at the beginning of the process, simultaneously using lithium–naphthalene complex, thus having a one-pot procedure for the formation and surface modification of MgNPs. The obtained MgNPs were purified and fully characterized, showing diameters in the range of 50-300 nm. Notably, when coated with chitosan the particles remained stable as dry powder for more than 10 months. We proved the possibility of generating a temperature rise of a few to several degrees once MgNPs were illuminated using a 810 nm diode laser operating in continuous wave mode: the temperature rise resulted significant (0-15 °C) and concentration dependent. We then investigated potential cytotoxicity of the MgNPs: we used HN13 epithelial cells, derived from a head and neck squamous cell carcinoma and the hepa1-6 cell line, derived from hepatocellular carcinoma and very low toxicity was observed for both nanosystems. Finally, in vivo photothermal therapy was performed on xenograft hepa1-6 tumor bearing mice: the animals were treated with MgNPs coated with chitosan and showed no sign of suffering after the injection. After 12 hours the tumor was exposed to near-infrared laser light. The results clearly showed an extensive damage to tumor tissue after only 2 minutes of laser irradiation at 3Wcm-1, while no damage was reported when the tumor was treated with the laser and saline alone in control group. Despite the lower photothermal efficiency of Mg with respect to Au NPs, we consider MgNPs a promising, safe and green candidate for future clinical translations.Keywords: chitosan, magnesium nanoparticles, nanomedicine, photothermal therapy
Procedia PDF Downloads 2721632 Red Blood Cells Deformability: A Chaotic Process
Authors: Ana M. Korol, Bibiana Riquelme, Osvaldo A. Rosso
Abstract:
Since erythrocyte deformability analysis is mostly qualitative, the development of quantitative nonlinear methods is crucial for restricting subjectivity in the study of cell behaviour. An electro-optic mechanic system called erythrodeformeter has been developed and constructed in our laboratory in order to evaluate the erythrocytes' viscoelasticity. A numerical method formulated on the basis of fractal approximation for ordinary (OBM) and fractionary Brownian motion (FBM), as well as wavelet transform analysis, are proposed to distinguish chaos from noise based on the assumption that diffractometric data involves both deterministic and stochastic components, so it could be modelled as a system of bounded correlated random walk. Here we report studies on 25 donors: 4 alpha thalassaemic patients, 11 beta thalassaemic patients, and 10 healthy controls non-alcoholic and non-smoker individuals. The Correlation Coefficient, a nonlinear parameter, showed evidence of the changes in the erythrocyte deformability; the Wavelet Entropy could quantify those differences which are detected by the light diffraction patterns. Such quantifiers allow a good deal of promise and the possibility of a better understanding of the rheological erythrocytes aspects and also could help in clinical diagnosis.Keywords: red blood cells, deformability, nonlinear dynamics, chaos theory, wavelet trannsform
Procedia PDF Downloads 621631 Effect of Oxidative Stress from Smoking on Erythrocyte Phosphatidylserine Externalization
Authors: Ratchaneewan Maneemaroj, Paveena Noisuwan, Chonlada Lakhonphon
Abstract:
The smoking is one of the major risk factors in Non-Communicable Disease. Free radicals from cigarette smoke can cause oxidative stress. The oxidative insults can lead to red blood cell (RBC) senescence and are involved in the clearance of red blood cells. The objective of the present study is to assess the association between smoke, oxidative stress evaluated with serum Malondialdehyde (MDA) level and phosphatidylserine (PS) externalization (biomarker of RBC senescence) evaluated with annexin V binding. A total of sixty-four male volunteers aged 25-60 years old were recruited in this study. MDA was measured by colorimetric method. Annexin V binding was detected by flow cytometry. Our results show that there was a significant increase in MDA levels in cigarette smokers as compared to non-smokers (p < 0.001). However, there was no significant different between annexin V binding (% gate) in cigarette smokers and non-smokers (p = 0.978). These results provide evidence of free radical from smoking is associated with oxidative damage to erythrocytes. However, our results suggest that PS externalization is unlikely to have a role in RBC senescence pathway of stressed erythrocytes from cigarette smoke. The other biomarker of RBC senescence should be determined on cigarette smoker erythrocytes.Keywords: malondialdehyde, phosphatidylserine, RBC senescence, annexin V
Procedia PDF Downloads 4401630 The Optimization of Topical Antineoplastic Therapy Using Controlled Release Systems Based on Amino-functionalized Mesoporous Silica
Authors: Lacramioara Ochiuz, Aurelia Vasile, Iulian Stoleriu, Cristina Ghiciuc, Maria Ignat
Abstract:
Topical administration of chemotherapeutic agents (eg. carmustine, bexarotene, mechlorethamine etc.) in local treatment of cutaneous T-cell lymphoma (CTCL) is accompanied by multiple side effects, such as contact hypersensitivity, pruritus, skin atrophy or even secondary malignancies. A known method of reducing the side effects of anticancer agent is the development of modified drug release systems using drug incapsulation in biocompatible nanoporous inorganic matrices, such as mesoporous MCM-41 silica. Mesoporous MCM-41 silica is characterized by large specific surface, high pore volume, uniform porosity, and stable dispersion in aqueous medium, excellent biocompatibility, in vivo biodegradability and capacity to be functionalized with different organic groups. Therefore, MCM-41 is an attractive candidate for a wide range of biomedical applications, such as controlled drug release, bone regeneration, protein immobilization, enzymes, etc. The main advantage of this material lies in its ability to host a large amount of the active substance in uniform pore system with adjustable size in a mesoscopic range. Silanol groups allow surface controlled functionalization leading to control of drug loading and release. This study shows (I) the amino-grafting optimization of mesoporous MCM-41 silica matrix by means of co-condensation during synthesis and post-synthesis using APTES (3-aminopropyltriethoxysilane); (ii) loading the therapeutic agent (carmustine) obtaining a modified drug release systems; (iii) determining the profile of in vitro carmustine release from these systems; (iv) assessment of carmustine release kinetics by fitting on four mathematical models. Obtained powders have been described in terms of structure, texture, morphology thermogravimetric analysis. The concentration of the therapeutic agent in the dissolution medium has been determined by HPLC method. In vitro dissolution tests have been done using cell Enhancer in a 12 hours interval. Analysis of carmustine release kinetics from mesoporous systems was made by fitting to zero-order model, first-order model Higuchi model and Korsmeyer-Peppas model, respectively. Results showed that both types of highly ordered mesoporous silica (amino grafted by co-condensation process or post-synthesis) are thermally stable in aqueous medium. In what regards the degree of loading and efficiency of loading with the therapeutic agent, there has been noticed an increase of around 10% in case of co-condensation method application. This result shows that direct co-condensation leads to even distribution of amino groups on the pore walls while in case of post-synthesis grafting many amino groups are concentrated near the pore opening and/or on external surface. In vitro dissolution tests showed an extended carmustine release (more than 86% m/m) both from systems based on silica functionalized directly by co-condensation and after synthesis. Assessment of carmustine release kinetics revealed a release through diffusion from all studied systems as a result of fitting to Higuchi model. The results of this study proved that amino-functionalized mesoporous silica may be used as a matrix for optimizing the anti-cancer topical therapy by loading carmustine and developing prolonged-release systems.Keywords: carmustine, silica, controlled, release
Procedia PDF Downloads 2661629 Health as an Agenda in Indian Politics: A Study of Election Manifestos in 16th General Elections
Authors: Kiran Bala
Abstract:
Health, education and employment opportunities available for a common citizen reflect the development status of a country. Health of an individual affects the growth of a country in every aspect. According to a study by WHO, India is estimated to lose more than $237 billion of its GDP over the period 2006-15 on account of premature death and morbidity from Non-communicable diseases alone. Each year 37 million people fall below poverty line due to high expenditure on health services they have to incur. Falling sick puts a double burden on them in terms of loss of income and expenditure on health care which pushes them further into debt and poverty. Adding to the gravity of situation, public spending on health in India has itself declined after liberalization from 1.3% of GDP in 1990 to 0.9% in 1999. The Approach Paper of the Government of India to the Twelfth Five Year Plan indicated that health expenditure alone as a per cent of GDP was about 1.4 per cent (B.E.) in 2011-12. It also mentioned that if one included expenditure on rural water supply and sanitation, the figure would be about 1.8 per cent. Given the abysmally low level of priority accorded to health in Indian economic policy, it becomes rather important to study the representation of health in the Indian public sphere. To this end, this study examines the prioritization of health in the public policy agenda of the national/regional political parties as evidenced in their election manifestos at a time when the nation is poised to go for the General Elections. The paper also focuses attention on the prioritization of health in the public perception as evidenced in their reasons for their preferences for a particular party or individual contestant. To arrive at the reasons for the priority level accorded by the political actors and the citizens, the study uses Focus groups of health policy makers, media persons, medical practitioners and voters. Collected data will be analysed in the theoretical framework of spiral of silence and agenda setting theory.Keywords: health, election manifestos, public perception, policies
Procedia PDF Downloads 3581628 Goblet cells and Mucin Related Gene Expression in Mice Infected with Eimeria papillata
Authors: Mohamed A. Dkhil, Denis Delic, Saleh Al-Quraishy
Abstract:
Coccidiosis causes considerable economic loss in the poultry industry. The current study aimed to investigate the response of goblet cells as well as the induced tissue damage during Eimeria papilata infection. Mice were infected with sporulated E. papillata oocyts. On day 5 post-infection, the fecal output was determined. Also, the jejunum was prepared for the histological, histochemical and molecular studies. Our results revealed that the intestinal coccidian infection with E. papillata induced a marked goblet cell hypoplasia and depleted mucus secretion. Also, the infection was able to alter the jejuna architecture and increased the apoptotic cells inside the villi. In addition, the real time PCR results indicated that, the inflammatory cytokines TNF-α, iNOS, IFN-y and IL-1β were significantly up-regulated. In contrast, the mRNA expression patterns of IL-6 in response to E. papillata infection did not differ significantly between control and infected mice. Moreover, the mRNA expression of TLR4 was significantly up-regulated, whereas the expression of MUC2 is significantly down-regulated upon infection. Further studies are required to understand the regulatory mechanisms of goblet cells related genes.Keywords: goblet cells, Eimeria papillata, mice, jejunum
Procedia PDF Downloads 2821627 Carbon Coated Yarn Supercapacitors: Parametric Study of Performance Output
Authors: Imtiaz Ahmed Khan, Sabu John, Sania Waqar, Lijing Wang, Mac Fergusson, Ilija Najdovski
Abstract:
Evolution of textiles, from its orthodox to more interactive role has stirred the researchers to uncover its application in numerous arenas. The idea of using textile based materials for wearable energy harvesting and storage devices have gained immense popularity. This is mainly due to textile comfort and flexibility features. In this work, nano-carbonous materials were infused on cellulosic fibers using caustic soda treatment. This paper presents the complete procedure of yarn supercapacitors fabrication process through dip coating technique and its characterization method. The main objective is to study, the effect of varying caustic soda concentration on mass loading of activated carbon on yarns and the related capacitance output of the designed yarn supercapacitor. Polyvinyl alcohol and Phosphoric acid were used as electrolyte in a two-electrode cell assembly to measure device electrochemical performance. The results show a promising increase in capacitance value using this technique.Keywords: yarn supercapacitors, activated carbon, dip coating, caustic soda, electrolyte, electrochemical characterization
Procedia PDF Downloads 4661626 Phytochemical Analysis and in vitro Biological Activities of an Ethyl Acetate Extract from the Peel of Punica granatum L. var. Dente di Cavallo
Authors: Silvia Di Giacomo, Marcello Locatelli, Simone Carradori, Francesco Cacciagrano, Chiara Toniolo, Gabriela Mazzanti, Luisa Mannina, Stefania Cesa, Antonella Di Sotto
Abstract:
Hyperglycemia represents the main pathogenic factor in the development of diabetes complications and has been found associated with mitochondrial dysfunction and oxidative stress, which in turn increase cell dysfunction. Therefore, counteract oxidative species appears to be a suitable strategy for preventing the hyperglycemia-induce cell damage and support the pharmacotherapy of diabetes and metabolic diseases. Antidiabetic potential of many food sources has been linked to the presence of polyphenolic metabolites, particularly flavonoids such as quercetin and its glycosylated form rutin. In line with this evidence, in the present study, we assayed the potential anti-hyperglycemic activity of an ethyl acetate extract from the peel of Punica granatum L. var. Dente di Cavallo (PGE), a fruit well known to traditional medicine for the beneficial properties of its edible juice. The effect of the extract on the glucidic metabolism has been evaluated by assessing its ability to inhibit α-amylase and α-glucosidase, two digestive enzymes responsible for the hydrolysis of dietary carbohydrates: their inhibition can delay the carbohydrate digestion and reduce glucose absorption, thus representing an important strategy for the management of hyperglycemia. Also, the PGE ability to block the release of advanced glycated end-products (AGEs), whose accumulation is known to be responsible for diabetic vascular complications, was studied. The iron-reducing and chelating activities, which are the primary mechanisms by which AGE inhibitors stop their metal-catalyzed formation, were evaluated as possible antioxidant mechanisms. At last, the phenolic content of PGE was characterized by chromatographic and spectrophotometric methods. Our results displayed the ability of PGE to inhibit α-amylase enzyme with a similar potency to the positive control: the IC₅₀ values were 52.2 (CL 27.7 - 101.2) µg/ml and 35.6 (CL 22.8 - 55.5) µg/ml for acarbose and PGE, respectively. PGE also inhibited the α-glucosidase enzyme with about a 25 higher potency than the positive controls of acarbose and quercetin. Furthermore, the extract exhibited ferrous and ferric ion chelating ability, with a maximum effect of 82.1% and 80.6% at a concentration of 250 µg/ml respectively, and reducing properties, reaching the maximum effect of 80.5% at a concentration of 10 µg/ml. At last, PGE was found able to inhibit the AGE production (maximum inhibition of 82.2% at the concentration of 1000 µg/ml), although with lower potency with respect to the positive control rutin. The phytochemical analysis of PGE displayed the presence of high levels of total polyphenols, tannins, and flavonoids, among which ellagic acid, gallic acid and catechin were identified. Altogether these data highlight the ability of PGE to control the carbohydrate metabolism at different levels, both by inhibiting the metabolic enzymes and by affecting the AGE formation likely by chelating mechanisms. It is also noteworthy that peel from pomegranate, although being a waste of juice production, can be reviewed as a nutraceutical source. In conclusion, present results suggest the possible role of PGE as a remedy for preventing hyperglycemia complications and encourage further in vivo studies.Keywords: anti-hyperglycemic activity, antioxidant properties, nutraceuticals, polyphenols, pomegranate
Procedia PDF Downloads 1891625 A Cross-Sectional Study of Parents’ Knowledge, Attitude, and Health-Seeking Behaviour Towards Childhood Tuberculosis during COVID-19 Pandemic: Lessons Learned from Indonesia
Authors: Windy Rakhmawati, Suryani Suryani, Sri Hendrawati, Nenden Nur Asriyani Maryam
Abstract:
Tuberculosis (TB) is one of the leading causes of death in the world. Fear of COVID-19 has made people reluctant to visit health facilities, leading to disruptions to childhood TB control programs, which may increase household transmission and delay diagnosis and treatment. This study aimed to describe parents' knowledge, attitudes, and health-seeking behaviour towards childhood TB during the COVID-19 pandemic. This cross-sectional study was performed on 392 parents with TB children in three provinces with the highest proportion of TB cases in Indonesia. This study was conducted from February to December 2022. The inclusion criteria of respondents were parents with a child aged 0-14 years old with TB diagnosis who live with their parents. Data were collected using the Knowledge, Attitude, and Practice (KAP) survey guidelines from the World Health Organization and analyzed descriptively, as well as Spearman’s correlation. Overall, 392 parents of children with TB had poor knowledge (51.8%) including about causes, risk factors, transmission, symptoms, treatment, and prevention, which about 52.3%, 55.1%, 61.2%, 69.6%, 100%, 59.2%, respectively. Parents' health service-seeking behaviour towards Child TB was not normally distributed (P < 0.05) with knowledge test results (.000) and Seeking Health Services (.000). Health-seeking behaviour of parents in pediatric TB care was self-medication or self-treatment (86.2%), Traditional health seeking behaviour (4.8%), and modern health seeking behaviour (8.9%). The correlation between knowledge and seeking health services (Sig= .609) means there is no correlation between knowledge about TB and parents' health-seeking behaviour. Furthermore, 60.2% of the respondents would be shocked if their child had TB. More than half of the families in this study have poor knowledge and did self-medication or self-treatment regarding health-seeking behaviour for TB disease. Therefore, health workers, especially nurses, must provide TB-related education and health promotion and emphasize the importance of early detection. Health workers can also optimize their role in caring for and providing care to patients by increasing their trust in health workers, which will impact health-seeking behaviour in the future.Keywords: attitude, child, health seeking behaviour, knowledge, tuberculosis
Procedia PDF Downloads 761624 Production of Poly-β-Hydroxybutyrate (PHB) by a Thermophilic Strain of Bacillus and Pseudomonas Species
Authors: Patience Orobosa Olajide
Abstract:
Five hydrocarbon degrading bacterial strains isolated from contaminated environment were investigated with respect to polyhydroxybutyrate (PHB) biosynthesis. Screening for bioplastic production was done on assay mineral salts agar medium containing 0.2% poly (3-hydroxybutyrate) as the sole carbon source. Two of the test bacteria were positive for PHB biosynthesis and were identified based on gram staining, biochemical tests, 16S rRNA gene sequence analysis as Pseudomonas aeruginosa and Bacillus licheniformis which grew at 37 and up to 65 °C respectively, thus suggesting the later to be thermotolerant. In this study, the effects of different carbon and nitrogen sources on PHB production in these strains were investigated. Maximum PHB production was obtained in 48 hr for the two strains and amounted to yields of 72.86 and 62.22 percentages for Bacillus licheniformis and Pseudomonas aeruginosa respectively. In these strains, glycine was the most efficient carbon sources for the production of PHB compared with other carbon (glucose, lactose, sucrose, Arabinose) and nitrogen (L- glycine, L-cysteine, DL-Tryptophan, and Potassium Nitrate) sources. The screening of microbial strains for industrial PHB production should be based on several factors including the cell’s capability to mineralize an inexpensive substrate, rate of growth and the extent of polymer accumulation.Keywords: bacteria, poly-3-hydroxybutyrate (PHB), hydrocarbon, thermotolerant
Procedia PDF Downloads 2021623 Antiprotozoal Activity of Peganum harmala against Babesiosis in Cattle
Authors: Muhammad Mustafa Jafar, Syed Ashar Mahfooz, Muhammad Ejaz Saleem, Muhammad Asif Raza, Asghar Abbas, Rao Zahid Abbas, Muhammad Kasib Khan, Hafiz Muhammad Ishaq
Abstract:
The Babesia gradually attained resistance against the synthetic medicines. To overcome the drug resistance, herbal therapy has gained more attention as compared to allopathic therapy. Peganumharmala (harmal) is a plant which has shown effective results against various protozoal diseases. Therefore, the present study was planned to monitor the efficacy of Peganumharmala (aqueous extract) against Babesiosis in cattle. For this purpose, a total of forty (n=40) infected animals were randomly divided into four equal groups (A, B, C, and D). Group A was treated with aqueous extract of Peganum harmala at 7.5 mg/kg, group B at 10 mg/kg and group C at 12.5 mg/kg of body weight. Group D served as a control group (normal). It was observed that there was a stabilization in hematological parameters (white and red blood cells, hemoglobin and Packed cell volume) in infected animals treated with Peganum harmala at different doses. Results of this study hence indicated that Peganum harmala extract at 12.5mg/kg BW is more effective against Babesiosis than lower doses.Keywords: Babesiosis, cattle, control, Peganum harmala
Procedia PDF Downloads 2921622 Isolation and Classification of Red Blood Cells in Anemic Microscopic Images
Authors: Jameela Ali Alkrimi, Abdul Rahim Ahmad, Azizah Suliman, Loay E. George
Abstract:
Red blood cells (RBCs) are among the most commonly and intensively studied type of blood cells in cell biology. The lack of RBCs is a condition characterized by lower than normal hemoglobin level; this condition is referred to as 'anemia'. In this study, a software was developed to isolate RBCs by using a machine learning approach to classify anemic RBCs in microscopic images. Several features of RBCs were extracted using image processing algorithms, including principal component analysis (PCA). With the proposed method, RBCs were isolated in 34 second from an image containing 18 to 27 cells. We also proposed that PCA could be performed to increase the speed and efficiency of classification. Our classifier algorithm yielded accuracy rates of 100%, 99.99%, and 96.50% for K-nearest neighbor (K-NN) algorithm, support vector machine (SVM), and neural network ANN, respectively. Classification was evaluated in highly sensitivity, specificity, and kappa statistical parameters. In conclusion, the classification results were obtained for a short time period with more efficient when PCA was used.Keywords: red blood cells, pre-processing image algorithms, classification algorithms, principal component analysis PCA, confusion matrix, kappa statistical parameters, ROC
Procedia PDF Downloads 4111621 Attenuation of Endotoxin Induced Hepatotoxicity by Dexamethasone, Melatonin and Pentoxifylline in White Albino Mice: A Comparative Study
Authors: Ammara Khan
Abstract:
Sepsis is characterized by an overwhelming surge of cytokines and oxidative stress to one of many factors, gram-negative bacteria commonly implicated. Despite major expansion and elaboration of sepsis pathophysiology and therapeutic approach; death rate remains very high in septic patients due to multiple organ damages including hepatotoxicity.The present study was aimed to ascertain the adequacy of three different drugs delivered separately and collectively- low dose steroid-dexamethasone (3mg/kg i.p) ,antioxidant-melatonin(10 mg/kg i.p) ,and phosphodiesterases inhibitor - pentoxifylline (75 mg/kg i.p)in endotoxin-induced hepatotoxicity in mice. Endotoxin/lipopolysaccharides induced hepatotoxicity was reproduced in mice by giving lipopolysaccharide of serotype E.Coli intraperitoneally. The preventive role was questioned by giving the experimental agent half an hour prior to LPS injection whereas the therapeutic potential of the experimental agent was searched out via post-LPS delivering. The extent of liver damage was adjudged via serum alanine aminotransferases (ALT) and aspartate aminotransferase (AST) estimation along with a histopathological examination of liver tissue. Dexamethasone is given before (Group 3) and after LPS (group 4) significantly attenuated LPS generated liver injury.Pentoxifylline generated similar results and serum ALT; AST histological alteration abated considerably (p≤ 0.05) both in animals subjected to pentoxifylline pre (Group 5) and post-treatment(Group 6). Melatonin was also prosperous in aversion (Group 7) and curation (Group 8) of LPS invoked hepatotoxicity as evident by lessening of augmented ALT (≤0.01) and AST (≤0.01) along with restoration of pathological changes in liver sections (p≤0.05). Combination therapies with dexamethasone in conjunction with melatonin (Group 9), dexamethasone together with pentoxifylline (Group 10), and pentoxifylline along with melatonin (Group 11) after LPS administration tapered LPS evoked hepatic dysfunction statistically considerably. In conclusion, both melatonin and pentoxifylline set up promising results in endotoxin-induced hepatotoxicity and can be used therapeutic adjuncts to conventional treatment strategies in sepsis-induced liver failure.Keywords: endotoxin/lipopolysacchride, dexamethasone, hepatotoxicity, melatonin, pentoxifylline
Procedia PDF Downloads 2841620 A QoE-driven Cross-layer Resource Allocation Scheme for High Traffic Service over Open Wireless Network Downlink
Authors: Liya Shan, Qing Liao, Qinyue Hu, Shantao Jiang, Tao Wang
Abstract:
In this paper, a Quality of Experience (QoE)-driven cross-layer resource allocation scheme for high traffic service over Open Wireless Network (OWN) downlink is proposed, and the related problem about the users in the whole cell including the users in overlap region of different cells has been solved.A method, in which assess models of the BestEffort service and the no-reference assess algorithm for video service are adopted, to calculate the Mean Opinion Score (MOS) value for high traffic service has been introduced. The cross-layer architecture considers the parameters in application layer, media access control layer and physical layer jointly. Based on this architecture and the MOS value, the Binary Constrained Particle Swarm Optimization (B_CPSO) algorithm is used to solve the cross-layer resource allocation problem. In addition,simulationresults show that the proposed scheme significantly outperforms other schemes in terms of maximizing average users’ MOS value for the whole system as well as maintaining fairness among users.Keywords: high traffic service, cross-layer resource allocation, QoE, B_CPSO, OWN
Procedia PDF Downloads 5451619 Alternative Hypotheses on the Role of Oligodendrocytes in Neurocysticercosis: Comprehensive Review
Authors: Humberto Foyaca Sibat, Lourdes de Fátima Ibañez Valdés
Abstract:
Background Cysticercosis (Ct) is a preventable and eradicable zoonotic parasitic disease secondary to a cestode infection by the larva form of pig tapeworm Taenia solium (Ts), mainly seen in people living in developing countries. When the cysticercus is in the brain parenchymal, intraventricular system, subarachnoid space (SAS), cerebellum, brainstem, optic nerve, or spinal cord, then it has named neurocysticercosis (NCC), and the often-clinical manifestations are headache and epileptic seizures/epilepsy among other less frequent symptoms and signs. In this study, we look for a manuscript related to the role played by oligodendrocytes in the pathogenesis of NCC. We review this issue and formulate some hypotheses regarding its role and the role played in the pathogenesis of calcified NCC and epileptic seizures, and secondary epilepsy. Method: We searched the medical literature comprehensively, looking for published medical subject heading (MeSH) terms like "neurocysticercosis", "pathogenesis of neurocysticercosis", "comorbidity in NCC"; OR "oligodendrocytes"; OR "oligodendrocyte precursor cells(OPC/NG2)"; OR "epileptic seizures(ES)/Epilepsy(Ep)/NCC" OR "oligodendrocytes(OLG)/ES/Ep”; OR "calcified NCC/OLG"; OR “OLG Ca2+.” Results: All selected manuscripts were peer-reviewed, and we did not find publications related to OLG/NCC.Keywords: oligodendrocytes, neurocysticercosis, oligodendrocytes, oligodendrocyte precursor cell, KG2, calcified neurocysticercosis, cellular calcium influx.
Procedia PDF Downloads 791618 Reduction of Fermentation Duration of Cassava to Remove Hydrogen Cyanide
Authors: Jean Paul Hategekimana, Josiane Irakoze, Eugene Niyonzima, Annick Ndekezi
Abstract:
Cassava (Manihot esculenta Crantz) is a root crop comprising an anti-nutritive factor known as cyanide. The compound can be removed by numerous processing methods such as boiling, fermentation, blanching, and sun drying to avoid the possibility of cyanide poisoning. Inappropriate processing mean can lead to disease and death. Cassava-based dishes are consumed in different ways, where cassava is cultivated according to their culture and preference. However, they have been shown to be unsafe based on high cyanide levels. The current study targeted to resolve the problem of high cyanide in cassava consumed in Rwanda. This study was conducted to determine the effect of slicing, blanching, and soaking time to reduce the fermentation duration of cassava for hydrogen cyanide (HCN) in mg/g removal. Cassava was sliced into three different portions (1cm, 2cm, and 5cm). The first portions were naturally fermented for seven days, where each portion was removed every 24 hours from soaking tanks and then oven dried at a temperature of 60°C and then milled to obtain naturally fermented cassava flours. Other portions of 1cm, 2cm, and 5cm were blanched for 2, 5, 10 min, respectively, and each similarly dried at 60°C and milled to produce blanched cassava flour. Other blanched portions were used to follow the previous fermentation steps. The last portions, which formed the control, were simply chopped. Cyanide content and starch content in mg/100g were investigated. According to the conducted analysis on different cassava treatments for detoxification, found that usual fermentation can be used, but for sliced portions aimed to size reduction for the easy hydrogen cyanide diffuse out and it takes four days to complete fermentation, which has reduced at 94.44% with significantly different (p<0.05)of total hydrogen cyanide contained in cassava to safe level of consumption, and what is recommended as more effective is to apply blanching combined with fermentation due to the fact that, it takes three days to complete hydrogen cyanide removal at 95.56% on significantly different (p<0.05) of reduction to the safe level of consumption.Keywords: cassava, cyanide, blanching, drying, fermentation
Procedia PDF Downloads 771617 Neuroprotective Effect of Tangeretin against Potassium Dichromate-Induced Acute Brain Injury via Modulating AKT/Nrf2 Signaling Pathway in Rats
Authors: Ahmed A. Sedik, Doaa Mahmoud Shuaib
Abstract:
Brain injury is a cause of disability and death worldwide. Potassium dichromate (PD) is an environmental contaminant widely recognized as teratogenic, carcinogenic, and mutagenic towards animals and humans. The aim of the present study was to investigate the possible neuroprotective effects of tangeretin (TNG) on PD-induced brain injury in rats. Forty male adult Wistar rats were randomly and blindly allocated into four groups (8 rats /group). The first group received saline intranasally (i.n.). The second group received a single dose of PD (2 mg/kg, i.n.). The third group received TNG (50 mg/kg; orally) for 14 days, followed by i.n. of PD on the last day of the experiment. Four groups received TNG (100 mg/kg; orally) for 14 days, followed by i.n. of PD on the last day of the experiment. 18- hours after the final treatment, behavioral parameters, neuro-biochemical indices, FTIR analysis, and histopathological studies were evaluated. Results of the present study revealed that rats intoxicated with PD promoted oxidative stress and inflammation via an increase in MDA and a decrease in Nrf2 signaling pathway and GSH levels with an increase in brain contents of TNF-α, IL-10, and NF-kβ and reduced AKT levels in brain homogenates. Treatment with TNG (100 mg/kg; orally) ameliorated behavioral, cholinergic activities and oxidative stress, decreased the elevated levels of pro-inflammatory mediators; TNF-α, IL-10, and NF-κβ elevated AKT pathway with corrected FTIR spectra with a decrease in brain content of chromium residues detected by atomic absorption spectrometry. Also, TNG administration restored the morphological changes as degenerated neurons and necrosis associated with PD intoxication. Additionally, TNG decreased Caspase-3 expression in the brain of PD rats. TNG plays a crucial role in AKT/Nrf2 pathway that is responsible for their antioxidant, anti-inflammatory effects, and apoptotic pathway against PD-induced brain injury in rats.Keywords: tangeretin, potassium dichromate, brain injury, AKT/Nrf2 signaling pathway, FTIR, atomic absorption spectrometry
Procedia PDF Downloads 1071616 The Beacon of Collective Hope: Mixed Method Study on the Participation of Indian Youth with Regard to Mass Demonstrations Fueled by Social Activism Media
Authors: Akanksha Lohmore, Devanshu Arya, Preeti Kapur
Abstract:
Rarely does the human mind look at the positive fallout of highly negative events. Positive psychology attempts to emphasize on the strengths and positives for human well-being. The present study examines the underpinning socio-cognitive factors of the protest movements regarding the gang rape case of December 16th, 2012 through the lens of positive psychology. A gamut of negative emotions came to the forum globally: of anger, shame, hatred, violence, death penalty for the perpetrators, amongst other equally strong. In relation to this incident, a number of questions can be raised. Can such a heinous crime have some positive inputs for contemporary society? What is it that has held people to protests for long even when they see faded lines of success in view? This paper explains the constant feeding of protests and continuation of movements by the robust model of Collective Hope by Snyder, a phenomenon unexplored by social psychologists. In this paper, mixed method approach was undertaken. Results confirmed the interaction of various socio-psychological factors that imitated the Snyders model of collective hope. Emergence of major themes was: Sense of Agency, Sense of Worthiness, Social Sharing and Common Grievances and Hope of Collective Efficacy. Statistical analysis (correlation and regression) showed significant relationship between media usage and occurrence of these themes among participants. Media-communication processes and educational theories for development of citizenship behavior can find implications from these results. Theory development as indicated by theorists working in the area of Social Psychology of Protests can be furthered by the direction of research.Keywords: agency, collective, hope, positive psychology, protest, social media
Procedia PDF Downloads 3651615 Biosurfactant-Mediated Nanoparticle Synthesis by Bacillus subtilis
Authors: Satya Eswari Jujjavarapu, Swasti Dhagat, Lata Upadhyay, Reecha Sahu
Abstract:
Silver nanoparticles have a broad range of antimicrobial and antifungal properties ranging from soaps, pastes to sterilization and drug delivery systems. These can be synthesized by physical, chemical and biological methods; biological methods being the most popular owing to their non-toxic nature and reduced energy requirements. Microbial surfactants, produced on the microbial cell surface or excreted extracellularly are an alternative to synthetic surfactants for the production of silver nanoparticles. Hence, they are also called as green molecules. Microbial lipopeptide surfactants (biosurfactant) exhibit anti-tumor and anti-microbial properties and can be used as drug delivery agents. In this study, biosurfactant was synthesized by using a strain of acillus subtilis. The biosurfactant thus produced was analysed by emulsification assay, oil spilling test, and haemolytic test. Biosurfactant-mediated silver nanoparticles were synthesised by microwave irradiation of the culture supernatant and further characterized by UV–vis spectroscopy for a range of 400-600 nm. The UV–vis spectra showed a surface plasmon resonance vibration band at 410 nm corresponding to the peak of silver nanoparticles.Keywords: biosurfactant, Bacillus subtilis, silver nano particle, lipopeptide
Procedia PDF Downloads 2441614 Hydrogen Production Using an Anion-Exchange Membrane Water Electrolyzer: Mathematical and Bond Graph Modeling
Authors: Hugo Daneluzzo, Christelle Rabbat, Alan Jean-Marie
Abstract:
Water electrolysis is one of the most advanced technologies for producing hydrogen and can be easily combined with electricity from different sources. Under the influence of electric current, water molecules can be split into oxygen and hydrogen. The production of hydrogen by water electrolysis favors the integration of renewable energy sources into the energy mix by compensating for their intermittence through the storage of the energy produced when production exceeds demand and its release during off-peak production periods. Among the various electrolysis technologies, anion exchange membrane (AEM) electrolyser cells are emerging as a reliable technology for water electrolysis. Modeling and simulation are effective tools to save time, money, and effort during the optimization of operating conditions and the investigation of the design. The modeling and simulation become even more important when dealing with multiphysics dynamic systems. One of those systems is the AEM electrolysis cell involving complex physico-chemical reactions. Once developed, models may be utilized to comprehend the mechanisms to control and detect flaws in the systems. Several modeling methods have been initiated by scientists. These methods can be separated into two main approaches, namely equation-based modeling and graph-based modeling. The former approach is less user-friendly and difficult to update as it is based on ordinary or partial differential equations to represent the systems. However, the latter approach is more user-friendly and allows a clear representation of physical phenomena. In this case, the system is depicted by connecting subsystems, so-called blocks, through ports based on their physical interactions, hence being suitable for multiphysics systems. Among the graphical modelling methods, the bond graph is receiving increasing attention as being domain-independent and relying on the energy exchange between the components of the system. At present, few studies have investigated the modelling of AEM systems. A mathematical model and a bond graph model were used in previous studies to model the electrolysis cell performance. In this study, experimental data from literature were simulated using OpenModelica using bond graphs and mathematical approaches. The polarization curves at different operating conditions obtained by both approaches were compared with experimental ones. It was stated that both models predicted satisfactorily the polarization curves with error margins lower than 2% for equation-based models and lower than 5% for the bond graph model. The activation polarization of hydrogen evolution reactions (HER) and oxygen evolution reactions (OER) were behind the voltage loss in the AEM electrolyzer, whereas ion conduction through the membrane resulted in the ohmic loss. Therefore, highly active electro-catalysts are required for both HER and OER while high-conductivity AEMs are needed for effectively lowering the ohmic losses. The bond graph simulation of the polarisation curve for operating conditions at various temperatures has illustrated that voltage increases with temperature owing to the technology of the membrane. Simulation of the polarisation curve can be tested virtually, hence resulting in reduced cost and time involved due to experimental testing and improved design optimization. Further improvements can be made by implementing the bond graph model in a real power-to-gas-to-power scenario.Keywords: hydrogen production, anion-exchange membrane, electrolyzer, mathematical modeling, multiphysics modeling
Procedia PDF Downloads 981613 Health Promoting Properties of Phytochemicals from Rosemary (Rosmarinus officinalis) for Cancer and Inflammatory Bowel Disease
Authors: Jeremy J. Johnson
Abstract:
Mediterranean herbs including rosemary (Rosmarinus officinalis) contain a variety of phytochemicals including diterpenes that possess extensive biological activity. Applications of diterpenes, including the more abundant forms carnosol and carnosic acid, have been shown to possess anti-cancer, anti-inflammatory, anti-oxidant, and anti-proliferation properties. To confirm these properties, we have evaluated rosemary extract and selected diterpenes for biological activity in cancer and inflammatory models. Our preliminary data have revealed that select diterpenes can disrupt androgen receptor functionality in prostate and breast cancer cells. This property is unique among natural products for hormone-responsive cancers. The second area of interest has been evaluating rosemary extract and selected diterpenes for activation of sestrin-2, an antioxidant protein, in colon cancer cells. A combination of in vitro and in vivo approaches have been utilized to characterize the activity of rosemary diterpenes in rosemary. Taken together, these results suggest that phytochemicals found in rosemary have distinct pharmacological actions for disrupting cell-signaling pathways in cancer and inflammatory bowel disease.Keywords: rosemary, diterpene, cancer, inflammation
Procedia PDF Downloads 1491612 SnSₓ, Cu₂ZnSnS₄ Nanostructured Thin Layers for Thin-Film Solar Cells
Authors: Elena A. Outkina, Marina V. Meledina, Aliaksandr A. Khodin
Abstract:
Nanostructured thin films of SnSₓ, Cu₂ZnSnS₄ (CZTS) semiconductors were fabricated by chemical processing to produce thin-film photoactive layers for photocells as a prospective lowest-cost and environment-friendly alternative to Si, Cu(In, Ga)Se₂, and other traditional solar cells materials. To produce SnSₓ layers, the modified successive ionic layer adsorption and reaction (SILAR) technique were investigated, including successive cyclic dipping into Na₂S solution and SnCl₂, NaCl, triethanolamine solution. To fabricate CZTS layers, the cyclic dipping into CuSO₄ with ZnSO₄, SnCl₂, and Na₂S solutions was used with intermediate rinsing in distilled water. The nano-template aluminum/alumina substrate was used to control deposition processes. Micromorphology and optical characteristics of the fabricated layers have been investigated. Analysis of 2D-like layers deposition features using nano-template substrate is presented, including the effect of nanotips in a template on surface charge redistribution and transport.Keywords: kesterite, nanotemplate, SILAR, solar cell, tin sulphide
Procedia PDF Downloads 1461611 Investigation of the Controversial Immunomodulatory Potential of Trichinella spiralis Excretory-Secretory Products versus Extracellular Vesicles Derived from These Products in vitro
Authors: Natasa Ilic, Alisa Gruden-Movsesijan, Maja Kosanovic, Sofija Glamoclija, Marina Bekic, Ljiljana Sofronic-Milosavljevic, Sergej Tomic
Abstract:
As a very promising candidate for modulation of immune response in the sense of biasing the inflammatory towards an anti-inflammatory type of response, Trichinella spiralis infection was shown to successfully alleviate the severity of experimental autoimmune encephalomyelitis, the animal model of human disease multiple sclerosis. This effect is achieved via its excretory-secretory muscle larvae (ES L1) products which affect the maturation status and function of dendritic cells (DCs) by inducing the tolerogenic status of DCs, which leads to the mitigation of the Th1 type of response and the activation of a regulatory type of immune response both in vitro and in vivo. ES L1 alone or via treated DCs successfully mitigated EAE in the same manner as the infection itself. On the other hand, it has been shown that T. spiralis infection slows down the tumour growth and significantly reduces the tumour size in the model of mouse melanoma, while ES L1 possesses a pro-apoptotic and anti-survival effect on melanoma cells in vitro. Hence, although the mechanisms still need to be revealed, T. spiralis infection and its ES L1 products have a bit of controversial potential to modulate both inflammatory diseases and malignancies. The recent discovery of T. spiralis extracellular vesicles (TsEVs) suggested that the induction of complex regulation of the immune response requires simultaneous delivery of different signals in nano-sized packages. This study aimed to explore whether TsEVs bare the similar potential as ES L1 to influence the status of DCs in initiation, progression and regulation of immune response, but also to investigate the effect of both ES L1 and TsEVs on myeloid derived suppressor cells (MDSC) which present the regular tumour tissue environment. TsEVs were enriched from the conditioned medium of T. spiralis muscle larvae by differential centrifugation and used for the treatment of human monocyte-derived DCs and MDSC. On DCs, TsEVs induced low expression of HLA DR and CD40, moderate CD83 and CD86, and increased expression of ILT3 and CCR7 on treated DCs, i.e., they induced tolerogenic DCs. Such DCs possess the capacity to polarize T cell immune response towards regulatory type, with an increased proportion of IL-10 and TGF-β producing cells, similarly to ES L1. These findings indicated that the ability of TsEVs to induce tolerogenic DCs favoring anti-inflammatory responses may be helpful in coping with diseases that involve Th1/Th17-, but also Th2-mediated inflammation. In MDSC in vitro model, although both ES L1 and TsEVs had the same impact on MDSC phenotype i.e., they acted suppressive, ES L1 treated MDSC, unlike TsEVs treated ones, induced T cell response characterized by the increased RoRγT and IFN-γ, while the proportion of regulatory cells was decreased followed by the decrease in IL-10 and TGF-β positive cells proportion within this population. These findings indicate the interesting ability of ES L1 to modulate T cells response via MDSC towards pro-inflamatory type, suggesting that, unlike TsEVs which consistently demonstrate the suppresive effect on inflammatory response, it could be used also for the development of new approaches aimed for the treatment of malignant diseases. Acknowledgment: This work was funded by the Promis project – Nano-MDCS-Thera, Science Fund, Republic of Serbia.Keywords: dendritic cells, myeloid derived suppressor cells, immunomodulation, Trichinella spiralis
Procedia PDF Downloads 2071610 The “Buffer Layer” An Improved Electrode-Electrolyte Interface For Solid-State Batteries
Authors: Gregory Schmidt
Abstract:
Solid-state lithium batteries are broadly accepted as promising candidates for application in the next generation of EVs as they should offer safer and higher-energy-density batteries. Nonetheless, their development is impeded by many challenges, including the resistive electrode–electrolyte interface originating from the removal of the liquid electrolyte that normally permeates through the porous cathode and ensures efficient ionic conductivity through the cell. One way to tackle this challenge is by formulating composite cathodes containing solid ionic conductors in their structure, but this approach will require the conductors to exhibit chemical stability, electrochemical stability, flexibility, and adhesion and is, therefore, limited to some materials. Recently, Arkema developed a technology called buffering layer which allows the transformation of any conventional porous electrode into a catholyte. This organic layer has a very high ionic conductivity at room temperature, is compatible with all active materials, and can be processed with conventional Gigafactory equipment. Moreover, this layer helps protect the solid ionic conductor from the cathode and anode materials. During this presentation, the manufacture and the electrochemical performance of this layer for different systems of cathode and anode will be discussed.Keywords: electrochemistry, all solid state battery, materials, interface
Procedia PDF Downloads 100