Search results for: vacuum induced freezing
645 Computational Fluid Dynamics (CFD) Simulation of Transient Flow in a Rectangular Bubble Column Using a Coupled Discrete Phase Model (DPM) and Volume of Fluid (VOF) Model
Authors: Sonia Besbes, Mahmoud El Hajem, Habib Ben Aissia, Jean Yves Champagne, Jacques Jay
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In this work, we present a computational study for the characterization of the flow in a rectangular bubble column. To simulate the dynamic characteristics of the flow, a three-dimensional transient numerical simulations based on a coupled discrete phase model (DPM) and Volume of Fluid (VOF) model are performed. Modeling of bubble column reactor is often carried out under the assumption of a flat liquid surface with a degassing boundary condition. However, the dynamic behavior of the top surface surmounting the liquid phase will to some extent influence the meandering oscillations of the bubble plume. Therefore it is important to capture the surface behavior, and the assumption of a flat surface may not be applicable. So, the modeling approach needs to account for a dynamic liquid surface induced by the rising bubble plume. The volume of fluid (VOF) model was applied for the liquid and top gas which both interacts with bubbles implemented with a discrete phase model. This model treats the bubbles as Lagrangian particles and the liquid and the top gas as Eulerian phases with a sharp interface. Two-way coupling between Eulerian phases and Lagrangian bubbles are accounted for in a single set continuous phase momentum equation for the mixture of the two Eulerian phases. The effect of gas flow rate on the dynamic and time-averaged flow properties was studied. The time averaged liquid velocity field predicted from simulations and from our previous PIV measurements shows that the liquid is entrained up flow in the wake of the bubbles and down flow near the walls. The simulated and measured vertical velocity profiles exhibit a reasonable agreement looking at the minimum velocity values near the walls and the maximum values at the column center.Keywords: bubble column, computational fluid dynamics (CFD), coupled DPM and VOF model, hydrodynamics
Procedia PDF Downloads 379644 The Hypolipidemic and Anti-Nephrotoxic Potentials of Vernonia calvoana Extract in Acetaminophen-Treated Male Wistar Rats
Authors: Godwin E. Egbung, Item J. Atangwho, Diana O. Odey, Eyong U. Eyong
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Background of the study: The frequent abuse of acetaminophen by field workers in Calabar metropolis necessitated the present study on the hypolipidemic and anti-nephrotoxic potentials of Vernonia calvoana (VC) extract in acetaminophen (paracetamol) treated male albino Wistar rats Methods:. Thirty-five (35) male albino Wistar rats weighing 100-150 g were divided into five (5) groups of seven rats each. Group 1 served as normal control, group 2 received normal saline after treatment with Acetaminophen (PCM), group 3 was treated with VC extracts (200 mg/kg body weight), group 4 received VC extracts ( 400 mg/kg body weight) and group 5 was administered 100 mg/kg body weight of Vitamin E. At the end of the 21 days treatment period, the animals were sacrificed using chloroform vapours, and blood was collected via cardiac puncture and used for analyses of haematological as well as biochemical indices. Results: Results indicated significant decreases (p < 0.001) in LDL-c, TC and TG levels in groups 3,4 and 5 relative to both the control as well as group 2, the atherogenic index showed a significant decrease at p < 0.001) in all treated groups compared with control and PCM- treated group. However, both extracts treated groups and vitamin E treated group showed significant (p < 0.001) increase in HDL-c relative to the control and PCM treated group. Serum potassium concentration was significantly (p < 0.05 and 0.001) reduced across all the treated groups compared with control and PCM- treated groups. Group 4 showed significant (p < 0.001) increase in RBC count, Hb, and PCV compared with PCM- treated group. Conclusions: We therefore conclude that ethanolic leaf extract of VC possesses probable anti-anemic, hypolipidemic potentials, and also ameliorates serum electrolyte imbalance in paracetamol- induced toxicity.Keywords: acetaminophen, haematological indices, hypolipidemic potentials, serum lipid profile, vernonia calvoana, wistar rats
Procedia PDF Downloads 253643 RNA-seq Analysis of Liver from NASH-HCC Model Mouse Treated with Streptozotocin-High Fat Diet
Authors: Bui Phuong Linh, Yuki Sakakibara, Ryuto Tanaka, Elizabeth H. Pigney, Taishi Hashiguchi
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Non-alcoholic steatohepatitis (NASH) is a chronic liver disease, often associated with type II diabetes, which sometimes progresses to more serious conditions such as liver fibrosis and hepatocellular carcinoma (HCC). NASH has become an important health problem worldwide, buttherapeutic agents for NASH have not yet been approved, and animal models with high clinical correlation are required. TheSTAM™ mouse shows the same pathological progression as human NASH patients and has been widely used for both drug efficacy and basic research, such as lipid profiling and gut microbiota research. In this study, we analyzed the RNA-seq data of STAM™mice at each pathological stage (steatosis, steatohepatitis, liver fibrosis, and HCC) and examined the clinical correlation at the genetic level. NASH was induced in male mice by a single subcutaneous injection of 200 µg streptozotocin solution 2 days after birth and feeding with high fat dietafter 4 weeks of age. The mice were sacrificed and livers collected at 6, 8, 10, 12, 16, and 20 weeks of age. For liver samples, the left lateral lobe was snap frozen in liquid nitrogen and stored at -80˚C for RNA-seq analysis. Total RNA of the cells was isolated using RNeasy mini kit. The gene expression of the canonical pathways in NASH progression from steatosis to hepatocellular carcinoma were analyzed, such as immune system process, oxidation-reduction process, lipid metabolic process. Moreover, since it has been reported that genetic traits are involved in the development of NASH-HCC, we next analyzed the genetic mutations in the STAM™mice. The number of individuals showing mutations in Mtorinvolved in Insulin signaling increases as the disease progresses, especially in the liver cancer phase. These results indicated a clinical correlation of gene profiles in the STAM™mouse.Keywords: steatosis, non-alcoholic steatohepatitis, fibrosis, hepatocellular carcinoma, RNA-seq
Procedia PDF Downloads 145642 Proliferative Effect of Some Calcium Channel Blockers on the Human Embryonic Kidney Cell Line
Authors: Lukman Ahmad Jamil, Heather M. Wallace
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Introduction: Numerous epidemiological studies have shown a positive as well as negative association and no association in some cases between chronic use of calcium channel blockers and the increased risk of developing cancer. However, these associations were enmeshed with controversies in the absence of laboratory based studies to back up those claims. Aim: The aim of this study was to determine in mechanistic terms the association between the long-term administration of nifedipine and diltiazem and increased risk of developing cancer using the human embryonic kidney (HEK293) cell line. Methods: Cell counting using the Trypan blue dye exclusion and 3-4, 5-Dimethylthiazol-2-yl-2, 5-diphenyl-tetrazolium bromide (MTT) assays were used to investigate the effect of nifedipine and diltiazem on the growth pattern of HEK293 cells. Protein assay using modified Lowry method and analysis of intracellular polyamines concentration using Liquid Chromatography – Tandem Mass Spectrometry (LC-MS) were performed to ascertain the mechanism through which chronic use of nifedipine increases the risk of developing cancer. Results: Both nifedipine and diltiazem significantly increased the proliferation of HEK293 cells dose and time dependently. This proliferative effect after 24, 48 and 72-hour incubation period was observed at 0.78, 1.56 and 25 µM for nifedipine and 0.39, 1.56 and 25 µM for diltiazem, respectively. The increased proliferation of the cells was found to be statistically significantly (p<0.05). Furthermore, the increased proliferation of the cells induced by nifedipine was associated with the increase in the protein content and elevated intracellular polyamines concentration level. Conclusion: The chronic use of nifedipine is associated with increased proliferation of cells with concomitant elevation of polyamines concentration and elevated polyamine levels have been implicated in many malignant transformations and hence, these provide a possible explanation on the link between long term use of nifedipine and development of some human cancers. Further studies are needed to evaluate the cause of this association.Keywords: cancer, nifedipine, polyamine, proliferation
Procedia PDF Downloads 186641 Nursing Experience for a Lung Cancer Patient Undergoing First Time Concurrent Chemotherapy and Radiation Therapy
Authors: Hui Ling Chen
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This article describes the experience of caring for a 68-year-old lung cancer patient undergoing the initial stage of concurrent chemotherapy and radiation therapy during the period of October 21 to November 16. In this study, the author collected data through observation, interviews, medical examination, and the use of Roy’s adaptation model as a guide for data collection and assessment. This study confirmed that chemotherapy induced nausea and vomiting, and radiation therapy impaired skin integrity. At the same time, the patient experienced an anxious reaction to the initial cancer diagnosis and the insertion of subcutaneous infusion ports at the start of medical treatment. Similarly, the patient’s wife shares his anxiety, not to mention the feeling of inadequacy from the lack of training in cancer care. In response, the nursing intervention strategy has included keeping the patient and his family informed of his treatment progress, transfer of cancer care knowledge, and providing them with spiritual support. For example, the nursing staff has helped them draw up a mutually agreeable dietary plan that best suits the wife’s cooking skills, provided them with knowledge in pre- and post-radiation skin care, as well as means to cope with nausea and vomiting reactions. The nursing staff has also worked on building rapport with the patient and his spouse, providing them with encouragement, caring attention and companionship. After the patient was discharged from the hospital, the nursing staff followed up with caring phone calls to help the patient and his family make life-style adjustments to normalcy. The author hopes that his distinctive nursing experience can be useful as a reference for the clinical care of lung cancer patients undergoing the initial stage of concurrent chemotherapy and radiation therapy treatment.Keywords: lung cancer, initiate diagnosis, concurrent chemotherapy and radiation therapy, nursing care
Procedia PDF Downloads 134640 Cholesterol Modulating Properties of a Proprietary Extract from Phyllanthus spp on Hypercholesteraemic Mice Models
Authors: Anne R. Fernandez, Mohammad Akmal Adnan, Tanes Prasat, Indu Bala Jaganath, Brian Kirby, Kamalan Jeevaratnam
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Introduction: Plants from the Phyllantus genus have been used indigenously for the treatment of a variety of ailments for generations. A cocktail of phytonutrients prepared from a plant of the genus Phyllanthus has demonstrated the potential to alleviate ailments which include cardiovascular disorders. In this study, we investigated the cholesterol modulating properties of a highly purified proprietary extract of a Phyllanthus species in hypercholesteraemic mice. Methods: Hypercholesteraemia was induced in ICR mice by ad-libitum feeding of high fat diet daily for six weeks. The mice were then divided into 3 groups and force fed with 10mg/kg of atorvastatin, 200mg/kg of the proprietary Phyllanthus extract and water respectively. Blood samples were taken at the end of fourth week of treatment by a tail prick. At the end of the eighth week of treatment, mice were sacrificed and serum levels of total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triglycerides were measured. Results: The mean cholesterol levels in the mice fed with high fat diet were 44% (p < 0.05) higher than the mice on normal diet thus validating the model developed. The plasma HDL was significantly elevated in mice treated with the formulation (p ˂ 0.05) in comparison to the statin-treated and control mice. The total cholesterol levels in the mice treated with the proprietary extract were reduced significantly (p < 0.05) at the end of 4 weeks of treatment in comparison to the mice treated with atorvastatin. By the end of 8 weeks of treatment, there was no significant difference in the cholesterol levels of the mice in all groups. Conclusion: These results demonstrate that this proprietary extract from Phyllanthus species has the beneficial effect of reducing total cholesterol level more rapidly than atorvastatin and increasing HDL levels. Since an increase in the HDL cholesterol can reduce the risk of heart disease, this proprietary extract is a useful and safe therapeutic option compared to atorvastatin.Keywords: high-density lipoprotein, hypercholesteraemic mice model, ICR mice, Phyllanthus spp.
Procedia PDF Downloads 438639 Ethyl Methane Sulfonate-Induced Dunaliella salina KU11 Mutants Affected for Growth Rate, Cell Accumulation and Biomass
Authors: Vongsathorn Ngampuak, Yutachai Chookaew, Wipawee Dejtisakdi
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Dunaliella salina has great potential as a system for generating commercially valuable products, including beta-carotene, pharmaceuticals, and biofuels. Our goal is to improve this potential by enhancing growth rate and other properties of D. salina under optimal growth conditions. We used ethyl methane sulfonate (EMS) to generate random mutants in D. salina KU11, a strain classified in Thailand. In a preliminary experiment, we first treated D. salina cells with 0%, 0.8%, 1.0%, 1.2%, 1.44% and 1.66% EMS to generate a killing curve. After that, we randomly picked 30 candidates from approximately 300 isolated survivor colonies from the 1.44% EMS treatment (which permitted 30% survival) as an initial test of the mutant screen. Among the 30 survivor lines, we found that 2 strains (mutant #17 and #24) had significantly improved growth rates and cell number accumulation at stationary phase approximately up to 1.8 and 1.45 fold, respectively, 2 strains (mutant #6 and #23) had significantly decreased growth rates and cell number accumulation at stationary phase approximately down to 1.4 and 1.35 fold, respectively, while 26 of 30 lines had similar growth rates compared with the wild type control. We also analyzed cell size for each strain and found there was no significant difference comparing all mutants with the wild type. In addition, mutant #24 had shown an increase of biomass accumulation approximately 1.65 fold compared with the wild type strain on day 5 that was entering early stationary phase. From these preliminary results, it could be feasible to identify D. salina mutants with significant improved growth rate, cell accumulation and biomass production compared to the wild type for the further study; this makes it possible to improve this microorganism as a platform for biotechnology application.Keywords: Dunaliella salina, ethyl methyl sulfonate, growth rate, biomass
Procedia PDF Downloads 234638 Effects of Garlic and Stevia Extract Following Aerobic Exercise on Hypothalamic Semaphorin 4A and Plexin D1 Genes Expression in High-Fat Diet-Induced Obese Rats
Authors: Sayyed-Javad Ziaolhagh, Mojtaba Hokmabadi
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Introduction: Childhood obesity is a serious medical condition that affects children and adolescents even in the central nervous system. Semaphorins also play a role in the inflammatory process of the nervous system. On the other hand, it has been stated that garlic and stevia extracts following aerobic exercise are effective on immune system inflammation in addition to aerobic activity. Materials and Methods: For 15 weeks, 50 3-week-old male Wistar rats were fed with conventional rodent chow for control and a high-fat diet to induce obesity. Obese rats then were randomly assigned into 7 groups (n=5) based on the Lee index: healthy control (C), obese (OBS), obese + garlic (OBS+GAR), obese + Stevia (OBS+STV), obese + aerobic exercise (OBS+EXE), obese + garlic + aerobic exercise (OBS+GAR+EXE), and obese + stevia + aerobic exercise (OBS+STV+EXE). Training groups completed a progressive aerobic running program (at 8-15 m/min, 5-20 min/day, 5 days/week), and Stevia and garlic extract group (250 mg/kg/day, 5 days/week) were given orally once a day. Real-time PCR was used to determine the levels of Semaphorin 4A, and Plexin D1 gene expressions in the hypothalamus. Fold change analysis with ANOVA was performed for statistical analysis, with a significance threshold of P<0.05. Results: Body weight increased significantly in OBS compared to C (p= 0.013), but was not significantly changed in all treatment rats. Moreover, Semaphorin 4A was significantly increased in obese compared to control group (p= 0.041) and after 8 weeks, stevia extract (p=0.006), aerobic exercise (p=0.012) and garlic extract + aerobic exercise (p=0.008) significantly decreased compared to obese rats. In addition, Plexin D1 genes were also found in the hypothalamus of both obese and control rats but were insignificantly up-regulated when compared with the obese group (p=0.950). Conclusion: High-fat diet caused neuroinflammation by elevation of sema4A in obese rats and stevia, stevia with aerobic and garlic with aerobic could reduce this inflammation in rats. Also, none of them could alter Plexin D1.Keywords: sema 4A, plexin D1, garlic, stevia
Procedia PDF Downloads 64637 Effect of a new Released Bio Organic-Fertilizer in Improving Tomato Growth in Hydroponic System and Under Greenhouse
Authors: Zayneb Kthiri, Walid Hamada
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The application of organic fertilizers is generally known to be useful to sustain soil fertility and plant growth, especially in poor soils, with less than 1% of organic matter, as it is very common in our Tunisian fields. Therefore, we focused on evaluating the effect of a new released liquid organic fertilizer named Solorga (with 5% of organic matter) compared to a reference product (Espartan: Kimitec, Spain) on tomato plant growth and physiology. Both fertilizers, derived from plant decomposition, were applied at an early stage in hydroponic system and under greenhouse. In hydroponic system, after 14 days of their application by root feeding, a significant difference was observed between treatments. Indeed, Solorga improved shoots and roots length, as well as the biomass respectively, by 45%, 27%, and 27.8% increase rate, while compared to control plants. However, Espartan induced less the measured parameters while compared to untreated control. Moreover, Solorga significantly increased the chlorophyll content by 42% compared to control and by 32% compared to Espartan. In the greenhouse, after 20 days of treatments, the results showed a significant effect of both fertilizers on SPAD index and the number of flowers blossom. Solorga increased the amount of chlorophyll present in the leaf by 7% compared to Espartan as well as the plant height under greenhouse. Moreover, the number of flowers blossom increased by 15% in plants treated with Solorga while compared to Espartan. Whereas, there is no notable difference between both organic fertilizers on the fruits blossom and the number of fruits per blossom. In conclusion, even though there is a difference in the organic matter between both fertilizers, Solorga improved better the plant growth in controlled conditions in hydroponic system while compared to Espartan. Altogether the obtained results are encouraging for the use of Solorga as a soil enriching source of organic matter to help plants to boost their growth and help them to overcome abiotic stresses linked to soil fertility.Keywords: tomato, plant growth, organic fertilizer, hydroponic system, greenhouse
Procedia PDF Downloads 126636 Continuity Through Best Practice. A Case Series of Complex Wounds Manage by Dedicated Orthopedic Nursing Team
Authors: Siti Rahayu, Khairulniza Mohd Puat, Kesavan R., Mohammad Harris A., Jalila, Kunalan G., Fazir Mohamad
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The greatest challenge has been in establishing and maintaining the dedicated nursing team. Continuity is served when nurses are assigned exclusively for managing wound, where they can continue to build expertise and skills. In addition, there is a growing incidence of chronic wounds and recognition of the complexity involved in caring for these patients. We would like to share 4 cases with different techniques of wound management. 1st case, 39 years old gentleman with underlying rheumatoid arthritis with chronic periprosthetic joint infection of right total knee replacement presented with persistent drainage over right knee. Patient was consulted for two stage revision total knee replacement. However, patient only agreed for debridement and retention of implant. After debridement, large medial and lateral wound was treated with Instillation Negative Pressure Wound Therapy Dressings. After several cycle, the wound size reduced, and conventional dressing was applied. 2nd case, 58 years old gentleman with underlying diabetes presented with right foot necrotizing fasciitis with gangrene of 5th toe. He underwent extensive debridement of foot with rays’ amputation of 5th toe. Post debridement patient was started on Instillation Negative Pressure Wound Therapy Dressings. After several cycle of VAC, the wound bed was prepared, and he underwent split skin graft over right foot. 3 rd case, 60 years old gentleman with underlying diabetes mellitus presented with right foot necrotizing soft tissue infection. He underwent rays’ amputation and extensive wound debridement. Upon stabilization of general condition, patient was discharge with regular wound dressing by same nurse and doctor during each visit to clinic follow up. After 6 months of follow up, the wound healed well. 4th case, 38-year-old gentleman had alleged motor vehicle accident and sustained closed fracture right tibial plateau. Open reduction and proximal tibial locking plate were done. At 2 weeks post-surgery, the patient presented with warm, erythematous leg and pus discharge from the surgical site. Empirical antibiotic was started, and wound debridement was done. Intraoperatively, 50cc pus was evacuated, unhealthy muscle and tissue debrided. No loosening of the implant. Patient underwent multiple wound debridement. At 2 weeks post debridement wound healed well, but the proximal aspect was unable to close immediately. This left the proximal part of the implant to be exposed. Patient was then put on VAC dressing for 3 weeks until healthy granulation tissue closes the implant. Meanwhile, antibiotic was change according to culture and sensitivity. At 6 weeks post the first debridement, the wound was completely close, and patient was discharge home well. At 3 months post operatively, patient wound and fracture healed uneventfully and able to ambulate independently. Complex wounds are too serious to be dealt with. Team managing complex wound need continuous support through the provision of educational tools to support their professional development, engagement with local and international expert, as well as highquality products that increase efficiencies in servicesKeywords: VAC (Vacuum Assisted Closure), empirical- initial antibiotics, NPWT- negative pressure wound therapy, NF- necrotizing fasciitis, gangrene- blackish discoloration due to poor blood supply
Procedia PDF Downloads 99635 Linearly Polarized Single Photon Emission from Nonpolar, Semipolar and Polar Quantum Dots in GaN/InGaN Nanowires
Authors: Snezana Lazic, Zarko Gacevic, Mark Holmes, Ekaterina Chernysheva, Marcus Müller, Peter Veit, Frank Bertram, Juergen Christen, Yasuhiko Arakawa, Enrique Calleja
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The study reports how the pencil-like morphology of a homoepitaxially grown GaN nanowire can be exploited for the fabrication of a thin conformal InGaN nanoshell, hosting nonpolar, semipolar and polar single photon sources (SPSs). All three SPS types exhibit narrow emission lines (FWHM~0.35 - 2 meV) and high degrees of linear optical polarization (P > 70%) in the low-temperature micro-photoluminescence (µ-PL) experiments and are characterized by a pronounced antibunching in the photon correlation measurements (gcorrected(2)(0) < 0.3). The quantum-dot-like exciton localization centers induced by compositional fluctuations within the InGaN nanoshell are identified as the driving mechanism for the single photon emission. As confirmed by the low-temperature transmission electron microscopy combined with cathodoluminescence (TEM-CL) study, the crystal region (i.e. non-polar m-, semi-polar r- and polar c-facets) hosting the single photon emitters strongly affects their emission wavelength, which ranges from ultra-violet for the non-polar to visible for the polar SPSs. The photon emission lifetime is also found to be facet-dependent and varies from sub-nanosecond time scales for the non- and semi-polar SPSs to a few nanoseconds for the polar ones. These differences are mainly attributed to facet-dependent indium content and electric field distribution across the hosting InGaN nanoshell. The hereby reported pencil-like InGaN nanoshell is the first single nanostructure able to host all three types of single photon emitters and is thus a promising building block for tunable quantum light devices integrated into future photonic and optoelectronic circuits.Keywords: GaN nanowire, InGaN nanoshell, linear polarization, nonpolar, semipolar, polar quantum dots, single-photon sources
Procedia PDF Downloads 382634 Dynamic Modelling of Hepatitis B Patient Using Sihar Model
Authors: Alakija Temitope Olufunmilayo, Akinyemi, Yagba Joy
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Hepatitis is the inflammation of the liver tissue that can cause whiteness of the eyes (Jaundice), lack of appetite, vomiting, tiredness, abdominal pain, diarrhea. Hepatitis is acute if it resolves within 6 months and chronic if it last longer than 6 months. Acute hepatitis can resolve on its own, lead to chronic hepatitis or rarely result in acute liver failure. Chronic hepatitis may lead to scarring of the liver (Cirrhosis), liver failure and liver cancer. Modelling Hepatitis B may become necessary in order to reduce its spread. So, dynamic SIR model can be used. This model consists of a system of three coupled non-linear ordinary differential equation which does not have an explicit formula solution. It is an epidemiological model used to predict the dynamics of infectious disease by categorizing the population into three possible compartments. In this study, a five-compartment dynamic model of Hepatitis B disease was proposed and developed by adding control measure of sensitizing the public called awareness. All the mathematical and statistical formulation of the model, especially the general equilibrium of the model, was derived, including the nonlinear least square estimators. The initial parameters of the model were derived using nonlinear least square embedded in R code. The result study shows that the proportion of Hepatitis B patient in the study population is 1.4 per 1,000,000 populations. The estimated Hepatitis B induced death rate is 0.0108, meaning that 1.08% of the infected individuals die of the disease. The reproduction number of Hepatitis B diseases in Nigeria is 6.0, meaning that one individual can infect more than 6.0 people. The effect of sensitizing the public on the basic reproduction number is significant as the reproduction number is reduced. The study therefore recommends that programme should be designed by government and non-governmental organization to sensitize the entire Nigeria population in order to reduce cases of Hepatitis B disease among the citizens.Keywords: hepatitis B, modelling, non-linear ordinary differential equation, sihar model, sensitization
Procedia PDF Downloads 74633 Passively Q-Switched 914 nm Microchip Laser for LIDAR Systems
Authors: Marco Naegele, Klaus Stoppel, Thomas Dekorsy
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Passively Q-switched microchip lasers enable the great potential for sophisticated LiDAR systems due to their compact overall system design, excellent beam quality, and scalable pulse energies. However, many near-infrared solid-state lasers show emitting wavelengths > 1000 nm, which are not compatible with state-of-the-art silicon detectors. Here we demonstrate a passively Q-switched microchip laser operating at 914 nm. The microchip laser consists of a 3 mm long Nd:YVO₄ crystal as a gain medium, while Cr⁴⁺:YAG with an initial transmission of 98% is used as a saturable absorber. Quasi-continuous pumping enables single pulse operation, and low duty cycles ensure low overall heat generation and power consumption. Thus, thermally induced instabilities are minimized, and operation without active cooling is possible while ambient temperature changes are compensated by adjustment of the pump laser current only. Single-emitter diode pumping at 808 nm leads to a compact overall system design and robust setup. Utilization of a microchip cavity approach ensures single-longitudinal mode operation with spectral bandwidths in the picometer regime and results in short laser pulses with pulse durations below 10 ns. Beam quality measurements reveal an almost diffraction-limited beam and enable conclusions concerning the thermal lens, which is essential to stabilize the plane-plane resonator. A 7% output coupler transmissivity is used to generate pulses with energies in the microjoule regime and peak powers of more than 600 W. Long-term pulse duration, pulse energy, central wavelength, and spectral bandwidth measurements emphasize the excellent system stability and facilitate the utilization of this laser in the context of a LiDAR system.Keywords: diode-pumping, LiDAR system, microchip laser, Nd:YVO4 laser, passively Q-switched
Procedia PDF Downloads 121632 A Comparison of Sulfur Mustard Cytotoxic Effects on the Two Human Lung Origin Cell Lines
Authors: P. Jost, L. Muckova, M. Matula, J. Pejchal, D. Jun, R. Stetina
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Sulfur mustard (bis(2-chlorethyl) sulfide) is highly toxic, chemical warfare agent that has been used in the past in several armed conflicts. Except for the skin, respiratory tract is one of the important routes of exposure. The elucidation and understanding of the mechanism of toxicity of SM have been effort intensive research. The multiple targets character of SM caused cellular damage resulted in activation of many different mechanisms which contribute to cellular response and participate in the final cytopathology effect. In our present work, we compared time-dependent changes in sulfur mustard exposed adult human lung fibroblasts NHLF and lung epithelial alveolar cell line A-549. Cell viability (MTT assay, Calcein-AM assay, and xCELLigence - real-time cell analysis), apoptosis (flow cytometry), mitochondrial membrane potential (Δψm, flow cytometry), reactive oxygen species induction (DC and cell cycle distribution (flow cytometry) were studied. We observed significantly decreased mitochondrial membrane potential and subsequent induction of apoptosis correlating with decreased cellular viability in the sulfur mustard exposed cells. In low concentrations, sulfur mustard-induced S-phase cell cycle arrest, on the other hand, high concentrations, cell cycle phase distribution of sulfur mustard exposed cells resembled cell cycle phase distribution of control group, which implies nonspecific cell cycle inhibition. Epithelial cells A-549 was found as more sensible to sulfur mustard toxicity. Acknowledgements: This work was supported by a long-term organization development plan Medical Aspects of Weapons of Mass Destruction of the Faculty of Military Health Sciences, University of Defence.Keywords: apoptosis, cell cycle, cytotoxicity, sulfur mustard
Procedia PDF Downloads 182631 Analysis of Secondary Peak in Hα Emission Profile during Gas Puffing in Aditya Tokamak
Authors: Harshita Raj, Joydeep Ghosh, Rakesh L. Tanna, Prabal K. Chattopadhyay, K. A. Jadeja, Sharvil Patel, Kaushal M. Patel, Narendra C. Patel, S. B. Bhatt, V. K. Panchal, Chhaya Chavda, C. N. Gupta, D. Raju, S. K. Jha, J. Raval, S. Joisa, S. Purohit, C. V. S. Rao, P. K. Atrey, Umesh Nagora, R. Manchanda, M. B. Chowdhuri, Nilam Ramaiya, S. Banerjee, Y. C. Saxena
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Efficient gas fueling is a critical aspect that needs to be mastered in order to maintain plasma density, to carry out fusion. This requires a fair understanding of fuel recycling in order to optimize the gas fueling. In Aditya tokamak, multiple gas puffs are used in a precise and controlled manner, for hydrogen fueling during the flat top of plasma discharge which has been instrumental in achieving discharges with enhanced density as well as energy confinement time. Following each gas puff, we observe peaks in temporal profile of Hα emission, Soft X-ray (SXR) and chord averaged electron density in a number of discharges, indicating efficient gas fueling. Interestingly, Hα temporal profile exhibited an additional peak following the peak corresponding to each gas puff. These additional peak Hα appeared in between the two gas puffs, indicating the presence of a secondary hydrogen source apart from the gas puffs. A thorough investigation revealed that these secondary Hα peaks coincide with Hard X- ray bursts which come from the interaction of runaway electrons with vessel limiters. This leads to consider that the runaway electrons (REs), which hit the wall, in turn, bring out the absorbed hydrogen and oxygen from the wall and makes the interaction of REs with limiter a secondary hydrogen source. These observations suggest that runaway electron induced recycling should also be included in recycling particle source in the particle balance calculations in tokamaks. Observation of two Hα peaks associated with one gas puff and their roles in enhancing and maintaining plasma density in Aditya tokamak will be discussed in this paper.Keywords: fusion, gas fueling, recycling, Tokamak, Aditya
Procedia PDF Downloads 393630 Acclimation of in vitro-Propagated Apple Plantlets as Affected by Light Intensity
Authors: Guem-Jae Chung, Jin-Hui Lee, Myung-Min Oh
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Environmental control of in vitro-propagated apple plantlets is required for successful acclimation to ex vitro due to its low survival rate. This study aimed to determine the proper lighting condition for ex vitro acclimation of the apple plantlets in plant factories. In vitro-propagated M9 apple plantlets treated with pre-acclimatization for 1 week were exposed to following light treatments for additional 6 weeks; 60 μmol·m⁻²·s⁻¹ (A), 100 μmol·m⁻²·s⁻¹ (B), 140 μmol·m⁻²·s⁻¹ (C), 180 μmol·m⁻²·s⁻¹ (D), 60 μmol·m⁻²·s⁻¹ → 100 μmol·m⁻²·s⁻¹ at 2 weeks (E) or 4 weeks (F), 60 μmol·m⁻²·s⁻¹ → 100 μmol·m⁻²·s⁻¹ at 2 weeks → 140 μmol·m⁻²·s⁻¹ at 4 weeks (G) and 60 μmol·m⁻²·s⁻¹ → 140 μmol·m⁻²·s⁻¹ at 4 weeks (H). Shoot height, total leaf area, soil-plant analysis development (SPAD) value, root length, fresh and dry weights of shoots and roots were measured every 2 weeks after transplanting. In addition, the photosynthetic rate was measured at 5 weeks after transplanting. At 6 weeks after transplanting, shoot height of B was significantly higher than the other treatments. SPAD value, total leaf area and root length of B and F were relatively higher than the other treatments. Root fresh weights of B, D, F, and G were relatively higher than those in the other treatments. D induced the highest value in shoot fresh weight probably due to stem hardening, but it also resulted in shoot damage in the early stage of acclimation. Photosynthetic rate at 5 weeks after the transplanting was significantly increased as the light intensity increased. These results suggest that 100 μmol·m⁻²·s⁻¹ for 6 weeks (B) or gradually increased treatment from 60 μmol·m⁻²·s⁻¹ to 140 μmol·m⁻²·s⁻¹ at 2 weeks interval (F) were the proper lighting conditions for successful acclimation of in vitro-propagated apple plantlets. Acknowledgment: This work was supported by Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (IPET) through Agri-Bio industry Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA) (315003051SB020).Keywords: acclimation, in vitro-propagated apple plantlets, light intensity, plant factory
Procedia PDF Downloads 120629 The Modulatory Effect of Some Antioxidants on Animal Model of Metabolic Syndrome Induced by High Fructose Fed Diet
Authors: Hala M. Abdelkarem, Abeer H. Gafeer
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The metabolic syndrome (Mts) is a constellation of risk factors. The main objective of this study is to compare the ameliorating effect of metformin, lipitor, orilstate, lipoic acid and carnitin on insulin, lipid profile, leptin, adenonectin levels in metabolic syndrom (high fructose fed rats HF). Seventy male albino rats were divided into seven groups. G1: normal control. G2: G7 rats fed HF for 8wks. After four wk HF feeding, G3, G4, G5, G6, and G7 were orally administered (200 mg/kg daily) metformin, lipitor, orilstate, lipoic acid and carnitin respectively. All drugs were adminiseterd once daily. After 8 weeks of feeding, a significant increase in blood glucose level was observed in HF fed rats compared to normal rats, but this increase was significantly decreased after administration of metformin and lipitor. The raised of serum insulin level in HF fed rats was significantly decreased after administration of lipoic, carnitin, metformin. Significant higher concentrations of triglycerides (TG), total cholesterol & low density lipoprotein cholesterol (LDL- C) were observed in HF fed rats and these increases were significantly lowered after the administration of all the previous drugs. There was a significant decrease in serum high density lipoprotein cholesterol (HDL-C) in HF group administration of all drugs alleviates this reduction. The increased of serum leptin level in HF group was decreased significantly in met and orilstate groups. Whereas the reduction of serum adiponectin level in HF fed rats was increased in Lipitor, carnitin, orilstate groups. These data suggested that benefial effect of metformin, lipitor, orilstate, lipoic acid carnitin in reducing risk for people with decreased insulin sensitivity, increased oxidative stress and hyperlipidemia such as those with the metabolic syndrome or type 2 diabetes.Keywords: metabolic syndrome, diabetes, proinflammation, antioxidants
Procedia PDF Downloads 314628 Effects of a 6-Month Caloric Restriction Induced-Weight Loss Program in Obese Postmenopausal Women with and without the Metabolic Syndrome: A MONET Study
Authors: Ahmed Ghachem, Denis Prud’homme, Rémi-Rabasa-Lhoret, M. Brochu
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Objective: To compare the effects of a CR on body composition, lipid profile and glucose homeostasis in obese postmenopausal women with and without MetS. Methods: Secondary analyses were performed on seventy-three inactive obese postmenopausal women (age: 57.7 ± 4.8 yrs; body mass index: 32.4 ± 4.6 kg/m2) who participated in the 6-month caloric restriction arm of a study of the Montreal-Ottawa New Emerging Team. The harmonized MetS definition was used to categorized participants with MetS [n = 20, 27.39%] and without MetS [n = 53, 72.61%]. Variables of interest were: body composition (DXA), body fat distribution (CT scan), glucose homeostasis at the fasting state and during a euglycemic/hyperinsulinemic clamp, fasting lipids and resting blood pressure. Results: By design, the MetS group had a worse cardiometabolic profile; while both groups were comparable for age. Fifty-five patients out of seventy-three displayed no change in MetS status after the intervention. Twelve participants out of twenty (or 60.0%) in the MetS group had no more MetS after weight loss (P= NS); while six participants out of fifty three (or 11.3%) in the other group developed the MetS after the intervention (P= NS). Overall, indices of body composition and body fat distribution improved significantly and similarly in both groups (P between 0.03 and 0.0001). Furthermore, with the exception of triglyceride levels and triglycerides/HDL-C ratio, which decrease significantly more in the MetS group (P ≤ 0.05), no difference was observed between groups for the other variables of the cardiometabolic profile. Conclusion: Despite no overall significant effects on MetS, heterogeneous results were obtained in response to weight loss in the present study; with some improving the MetS while other displaying deteriorations. Further studies are needed in order to identify factors and phenotypes associated with positive and negative cardiometabolic responses to CR intervention.Keywords: menopause, obesity, physical inactivity, metabolic syndrome, caloric restriction, weight loss
Procedia PDF Downloads 334627 Neuroprotective Effect of Hypericum Perforatum against Neurotoxicity and Alzheimer's Disease (Experimental Study in Mice)
Authors: Khayra Zerrouki, Noureddine Djebli, Esra Eroglu, Afife Mat, Ozhan Gul
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Neurodegenerative diseases of the human brain comprise a variety of disorders that affect an increasing percentage of the population. Alzheimer’s disease (AD) is a complex, multifactorial, heterogeneous mental illness, which is characterized by an age-dependent loss of memory and an impairment of multiple cognitive functions, but this 10 last years it concerns the population most and most young. Hypericum perforatum has traditionally been used as an external anti-inflammatory and healing remedy for the treatment of swellings, wounds and burns, diseases of the alimentary tract and psychological disorders. It is currently of great interest due to new and important therapeutic applications. In this study, the chemical composition of methanolic extract of Hypericum perforatum (HPM) was analysed by using high performance liquid chromatography – diode array detector (HPLC-DAD). The in vitro antioxidant activity of HPM was evaluated by using several antioxidant tests. HSM exhibits inhibitory capacity against posphatidylcholine liposome peroxidation, induced with iron and ascorbic acid, scavenge DPPH and superoxide radicals and act as reductants. The cytotoxic activity of HSM was also determined by using MTT cell viability assay on HeLa and NRK-52E cell lines. The in vivo activity studies in Swiss mice were determined by using behavioral, memory tests and histological study. According to tests results HPM that may be relevant to the treatment of cognitive disorders. The results of chemical analysis showed a hight level of hyperforin and quercitin that had an important antioxidant activity proved in vitro with the DPPH, anti LPO and SOD; this antioxidant activity was confirmed in vivo after the non-toxic results by means of improvement in behavioral and memory than the reducing shrunken in pyramidal cells of mice brains.Keywords: AlCl3, alzheimer, mice, neuroprotective, neurotoxicity, phytotherapy
Procedia PDF Downloads 494626 Ectoine: A Compatible Solute in Radio-Halophilic Stenotrophomonas sp. WMA-LM19 Strain to Prevent Ultraviolet-Induced Protein Damage
Authors: Wasim Sajjad, Manzoor Ahmad, Sundas Qadir, Muhammad Rafiq, Fariha Hasan, Richard Tehan, Kerry L. McPhail, Aamer Ali Shah
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Aim: This study aims to investigate the possible radiation protective role of a compatible solute in the tolerance of radio-halophilic bacterium against stresses, like desiccation and exposure to ionizing radiation. Methods and Results: Nine different radio-resistant bacteria were isolated from desert soil, where strain WMA-LM19 was chosen for detailed studies on the basis of its high tolerance for ultraviolet radiation among all these isolates. 16S rRNA gene sequencing indicated that the bacterium was closely related to Stenotrophomonas sp. (KT008383). A bacterial milking strategy was applied for extraction of intracellular compatible solutes in 70% (v/v) ethanol, which were purified by high-performance liquid chromatography (HPLC). The compound was characterized as ectoine by 1H and 13C nuclear magnetic resonance (NMR), and mass spectrometry (MS). Ectoine demonstrated more efficient preventive activity (54.80%) to erythrocyte membranes and also inhibited oxidative damage to proteins and lipids in comparison to the standard ascorbic acid. Furthermore, a high level of ectoine-mediated protection of bovine serum albumin against ionizing radiation (1500-2000 Jm-2) was observed, as indicated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. Conclusion: The results indicated that ectoine can be used as a potential mitigator and radio-protective agent to overcome radiation- and salinity-mediated oxidative damage in extreme environments. Significance and Impact of the Study: This study shows that ectoine from radio-halophiles can be used as a potential source in topical creams as sunscreen. The investigation of ectoine as UV protectant also changes the prospective that radiation resistance is specific only to molecular adaptation.Keywords: ectoine, anti-oxidant, stenotrophomonas sp., ultraviolet radiation
Procedia PDF Downloads 201625 Biological Activities of Protease Inhibitors from Cajanus cajan and Phaseolus limensis
Authors: Tooba N. Shamsi, Romana Perveen, Sadaf Fatima
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Protease Inhibitors (PIs) are widespread in nature, produced by animals, plants and microorganisms. They play vital role in various biological activities by keeping a check on activity of proteases. Present study aims to investigate antioxidant and anti-inflammatory properties of PPI from Cajanus cajan (CCTI) and Phaseolus limensis (LBTI). PPI was purified from C. cajan (PUSA-992) by ammonium sulfate precipitation followed by ion exchange chromatography. The anti-oxidant activity was analyzed by two most common radical scavenging assays of FRAP (ferric reducing antioxidant power) and DPPH (1,1- diphenyl-2-picrylhydrazyl). Also, in-vitro anti-inflammatory activity was evaluated using albumin denaturation assay and membrane stabilization assay at different concentrations. Ascorbic acid and aspirin were used as a standards for antioxidant and anti-inflammatory assays respectively. The PPIs were also checked for antimicrobial activity against a number of bacterial strains. The CCTI and LBTI showed DPPH radical scavenging activity in a concentration–dependent manner with IC50 values 544 µg/ml and 506 µg/ml respectively comparative to ascorbic acid which was 258 µg/ml. Following FRAP assay, it was evaluated that LBTI had 87.5% and CCTI showed 84.4% antioxidant activity, taking value of standard ascorbic acid to be 100%. The PPIs also showed in-vitro anti‐inflammatory activity by inhibiting the heat induced albumin denaturation with IC50 values of 686 µg/ml and 615 µg/ml for CCTI and LBTI respectively compared to the standard (aspirin) which was 70.8 µg/ml. Red blood cells membrane stabilization with IC50 values of 641 µg/ml and 587 µg/ml for CCTI and LBTI respectively against aspirin which showed IC50 value of 70.4 µg/ml. PPIs showed antibacterial activity against 7 known strains while there was apparently no action against fungi.Keywords: Cajanus cajan, Phaseolus limensis, Lima beans, protein protease inhibitor, antioxidant, anti-inflammatory, antimicrobial activity
Procedia PDF Downloads 286624 Rock-Bed Thermocline Storage: A Numerical Analysis of Granular Bed Behavior and Interaction with Storage Tank
Authors: Nahia H. Sassine, Frédéric-Victor Donzé, Arnaud Bruch, Barthélemy Harthong
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Thermal Energy Storage (TES) systems are central elements of various types of power plants operated using renewable energy sources. Packed bed TES can be considered as a cost–effective solution in concentrated solar power plants (CSP). Such a device is made up of a tank filled with a granular bed through which heat-transfer fluid circulates. However, in such devices, the tank might be subjected to catastrophic failure induced by a mechanical phenomenon known as thermal ratcheting. Thermal stresses are accumulated during cycles of loading and unloading until the failure happens. For instance, when rocks are used as storage material, the tank wall expands more than the solid medium during charge process, a gap is created between the rocks and tank walls and the filler material settles down to fill it. During discharge, the tank contracts against the bed, resulting in thermal stresses that may exceed the wall tank yield stress and generate plastic deformation. This phenomenon is repeated over the cycles and the tank will be slowly ratcheted outward until it fails. This paper aims at studying the evolution of tank wall stresses over granular bed thermal cycles, taking into account both thermal and mechanical loads, with a numerical model based on the discrete element method (DEM). Simulations were performed to study two different thermal configurations: (i) the tank is heated homogeneously along its height or (ii) with a vertical gradient of temperature. Then, the resulting loading stresses applied on the tank are compared as well the response of the internal granular material. Besides the study of the influence of different thermal configurations on the storage tank response, other parameters are varied, such as the internal angle of friction of the granular material, the dispersion of particles diameters as well as the tank’s dimensions. Then, their influences on the kinematics of the granular bed submitted to thermal cycles are highlighted.Keywords: discrete element method (DEM), thermal cycles, thermal energy storage, thermocline
Procedia PDF Downloads 398623 Phytochemical Exploration of Plectranthus stocksii Hook. F. for Antioxidant and Cytotoxic Properties
Authors: Kasipandi Muniyandi, Parimelazhagan Thangaraj
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Plants are important prospective wealth of a country, combination of local health care information about a specific plant together with data published by several groups of scientists, can help in deciding whether it should be considered acceptable for medicinal use. In the developed countries, too, plant-derived drugs may be of importance. The wide variety of ailments that are being treated with Plectranthus is an indication of the medicinal value of the genus. A number of species are not toxic and so may be taken orally, whilst others are used topically on the skin or as enemas. This study was designed to evaluate the different properties of Plectranthus stocksii and the aerial parts were collected and extracted with petroleum ether, chloroform, ethyl acetate, acetone and methanol by Soxhlet apparatus and finally macerated with hot water. The quantification assays revealed that, leaf methanol extract showed higher total phenolic (415.41 mg GAE/ g extract) and tannin (177.53 mg GAE/ g extract) contents whereas leaf ethyl acetate exhibited higher flavonoids (777.11 mg RE/ g extract) content. The antioxidant efficiency of the extracts was analyzed by various radical scavenging assays. Among the different antioxidant assays, leaf ethyl acetate extract showed higher free radical scavenging activities against DPPH (IC50 = 3.46 µg/mL), ABTS (27417.65 µM TE/ g extract), FRAP (152.17 mM Fe(II)E/ mg extract) NO• radical (21.46%) and Superoxide radical (IC50 = 24.16 µg/mL) assays. All the parts P. stocksii extracts showed significant protection against OH• induced DNA damage at 50 µg concentration. The HPLC analysis of leaf ethyl acetate extract revealed the presence of Quercetin (30.29 µg/mg of extract) was the major compound. Anticancer activity of leaf ethyl acetate extract showed better IC50 values were 48.87 and 36.08 µg/ mL against MCF-7 and Caco-2 respectively. From this study, P. stocksii can act as a potent antioxidant and cytotoxic antimicrobial agent. The scope for drug development from this plant is endless and there is undoubtedly a call for further research in pharmaceutical industries.Keywords: antioxidant, cytotoxicity, phenolics, plectranthus stocksii
Procedia PDF Downloads 371622 DNA Fragmentation and Apoptosis in Human Colorectal Cancer Cell Lines by Sesamum indicum Dried Seeds
Authors: Mohd Farooq Naqshbandi
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The four fractions of aqueous extract of Sesame Seeds (Sesamum indicum L.) were studied for invitro DNA fragmentation, cell migration, and cellular apoptosis on SW480 and HTC116 human colorectal cancer cell lines. The seeds of Sesamum indicum were extracted with six solvents, including Methanol, Ethanol, Aqueous, Chloroform, Acetonitrile, and Hexane. The aqueous extract (IC₅₀ value 154 µg/ml) was found to be the most active in terms of cytotoxicity with SW480 human colorectal cancer cell lines. Further fractionation of this aqueous extract on flash chromatography gave four fractions. These four fractions were studied for anticancer and DNA binding studies. Cell viability was assessed by colorimetric assay (MTT). IC₅₀ values for all these four fractions ranged from 137 to 548 µg/mL for the HTC116 cancer cell line and 141 to 402 µg/mL for the SW480 cancer cell line. The four fractions showed good anticancer and DNA binding properties. The DNA binding constants ranged from 10.4 ×10⁴ 5 to 28.7 ×10⁴, showing good interactions with DNA. The DNA binding interactions were due to intercalative and π-π electron forces. The results indicate that aqueous extract fractions of sesame showed inhibition of cell migration of SW480 and HTC116 human colorectal cancer cell lines and induced DNA fragmentation and apoptosis. This was demonstrated by calculating the low wound closure percentage in cells treated with these fractions as compared to the control (80%). Morphological features of nuclei of cells treated with fractions revealed chromatin compression, nuclear shrinkage, and apoptotic body formation, which indicate cell death by apoptosis. The flow cytometer of fraction-treated cells of SW480 and HTC116 human colorectal cancer cell lines revealed death due to apoptosis. The results of the study indicate that aqueous extract of sesame seeds may be used to treat colorectal cancer.Keywords: Sesamum indicum, cell migration inhibition, apoptosis induction, anticancer activity, colorectal cancer
Procedia PDF Downloads 77621 Generation of Ultra-Broadband Supercontinuum Ultrashort Laser Pulses with High Energy
Authors: Walid Tawfik
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The interaction of intense short nano- and picosecond laser pulses with plasma leads to reach variety of important applications, including time-resolved laser induced breakdown spectroscopy (LIBS), soft x-ray lasers, and laser-driven accelerators. The progress in generating of femtosecond down to sub-10 fs optical pulses has opened a door for scientists with an essential tool in many ultrafast phenomena, such as femto-chemistry, high field physics, and high harmonic generation (HHG). The advent of high-energy laser pulses with durations of few optical cycles provided scientists with very high electric fields, and produce coherent intense UV to NIR radiation with high energy which allows for the investigation of ultrafast molecular dynamics with femtosecond resolution. In this work, we could experimentally achieve the generation of a two-octave-wide supercontinuum ultrafast pulses extending from ultraviolet at 3.5 eV to the near-infrared at 1.3 eV in neon-filled capillary fiber. These pulses are created due to nonlinear self-phase modulation (SPM) in neon as a nonlinear medium. The measurements of the generated pulses were performed using spectral phase interferometry for direct electric-field reconstruction. A full characterization of the output pulses was studied. The output pulse characterization includes the pulse width, the beam profile, and the spectral bandwidth. Under optimization conditions, the reconstructed pulse intensity autocorrelation function was exposed for the shorts possible pulse duration to achieve transform-limited pulses with energies up to 600µJ. Furthermore, the effect of variation of neon pressure on the pulse-width was studied. The nonlinear SPM found to be increased with the neon pressure. The obtained results may give an opportunity to monitor and control ultrafast transit interaction in femtosecond chemistry.Keywords: femtosecond laser, ultrafast, supercontinuum, ultra-broadband
Procedia PDF Downloads 198620 Elucidating the Genetic Determinism of Seed Protein Plasticity in Response to the Environment Using Medicago truncatula
Authors: K. Cartelier, D. Aime, V. Vernoud, J. Buitink, J. M. Prosperi, K. Gallardo, C. Le Signor
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Legumes can produce protein-rich seeds without nitrogen fertilizer through root symbiosis with nitrogen-fixing rhizobia. Rich in lysine, these proteins are used for human nutrition and animal feed. However, the instability of seed protein yield and quality due to environmental fluctuations limits the wider use of legumes such as pea. Breeding efforts are needed to optimize and stabilize seed nutritional value, which requires to identify the genetic determinism of seed protein plasticity in response to the environment. Towards this goal, we have studied the plasticity of protein content and composition of seeds from a collection of 200 Medicago truncatula ecotypes grown under four controlled conditions (optimal, drought, and winter/spring sowing). A quantitative analysis of one-dimensional protein profiles of these mature seeds was performed and plasticity indices were calculated from each abundant protein band. Genome-Wide Association Studies (GWAS) from these data identified major GWAS hotspots, from which a list of candidate genes was obtained. A Gene Ontology Enrichment Analysis revealed an over-representation of genes involved in several amino acid metabolic pathways. This led us to propose that environmental variations are likely to modulate amino acid balance, thus impacting seed protein composition. The selection of candidate genes for controlling the plasticity of seed protein composition was refined using transcriptomics data from developing Medicago truncatula seeds. The pea orthologs of key genes were identified for functional studies by mean of TILLING (Targeting Induced Local Lesions in Genomes) lines in this crop. We will present how this study highlighted mechanisms that could govern seed protein plasticity, providing new cues towards the stabilization of legume seed quality.Keywords: GWAS, Medicago truncatula, plasticity, seed, storage proteins
Procedia PDF Downloads 133619 Anti-Obesity Activity of Garcinia xanthochymus: Biochemical Characterization and In vivo Studies in High Fat Diet-Rat Model
Authors: Mahesh M. Patil, K. A. Anu-Appaiah
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Overweight and obesity is a serious medical problem, increasing in prevalence, and affecting millions worldwide. Investigators have been trying from decades to articulate the burden of obesity and related risk factors. To answer this problem, we suggest a new therapeutic anti-obesity compounds from Garcinia xanthochymus fruit. However, there is little published scientific information on non-hydroxycitric acid Garcinia species. Our findings include biochemical characterization of the fruit; in vivo toxicity and bio-efficacy study of G. xanthochymus in high fat diet wistar rat model. We observed that Garcinia pericarp is a rich source of organic acids, polyphenols, mono- (40.63%) and poly-unsaturated fatty acids (16.45%; omega-3: 10.02%). Toxicological studies have showed that Garcinia is safe and had no observed adverse effect level up to 400 mg/kg/day. Body weight and food intake was significantly (P<0.05) reduced in oral gavage treated rats (sonicated Garcinia powder) in 13 weeks. Subcutaneous fat was significantly (P<0.05) reduced in Garcinia treated rats. Hepatocytes significantly (p<0.05) overexpressed sterol regulatory element binding protein 2, liver X receptor- α, liver X receptor- β, lipoprotein lipase and monoacylglycerol lipase. Fatty acid binding protein 1 and peroxisome proliferator activated receptor- α were down regulated as assessed by real time qPCR. Currently our research is focused on the adipocyte obesity related gene expressions, effect of Garcinia on 3T3-adipocyte cell lines and high fat diet induced mice model. This in vivo pre-clinical data suggests that G. xanthochymus may have clinical utility for the treatment of obesity. However, further studies are required to establish its potency.Keywords: Garcinia xanthochymus, anti-obesity, high fat diet, real time qPCR
Procedia PDF Downloads 246618 Stability of Pump Station Cavern in Chagrin Shale with Time
Authors: Mohammad Moridzadeh, Mohammad Djavid, Barry Doyle
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An assessment of the long-term stability of a cavern in Chagrin shale excavated by the sequential excavation method was performed during and after construction. During the excavation of the cavern, deformations of rock mass were measured at the surface of excavation and within the rock mass by surface and deep measurement instruments. Rock deformations were measured during construction which appeared to result from the as-built excavation sequence that had potentially disturbed the rock and its behavior. Also some additional time dependent rock deformations were observed during and post excavation. Several opinions have been expressed to explain this time dependent deformation including stress changes induced by excavation, strain softening (or creep) in the beddings with and without clay and creep of the shaley rock under compressive stresses. In order to analyze and replicate rock behavior observed during excavation, including current and post excavation elastic, plastic, and time dependent deformation, Finite Element Analysis (FEA) was performed. The analysis was also intended to estimate long term deformation of the rock mass around the excavation. Rock mass behavior including time dependent deformation was measured by means of rock surface convergence points, MPBXs, extended creep testing on the long anchors, and load history data from load cells attached to several long anchors. Direct creep testing of Chagrin Shale was performed on core samples from the wall of the Pump Room. Results of these measurements were used to calibrate the FEA of the excavation. These analyses incorporate time dependent constitutive modeling for the rock to evaluate the potential long term movement in the roof, walls, and invert of the cavern. The modeling was performed due to the concerns regarding the unanticipated behavior of the rock mass as well as the forecast of long term deformation and stability of rock around the excavation.Keywords: Cavern, Chagrin shale, creep, finite element.
Procedia PDF Downloads 342617 Formulation and Evaluation of Metformin Hydrochloride Microparticles via BÜCHI Nano-Spray Dryer B-90
Authors: Tamer Shehata
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Recently, nanotechnology acquired a great interest in the field of pharmaceutical production. Several pharmaceutical equipment were introduced into the research field for production of nanoparticles, among them, BÜCHI’ fourth generation nano-spray dryer B-90. B-90 is specialized with single step of production and drying of nano and microparticles. Currently, our research group is investigating several pharmaceutical formulations utilizing BÜCHI Nano-Spray Dryer B-90 technology. One of our projects is the formulation and evaluation of metformin hydrochloride mucoadhesive microparticles for treatment of type 2-diabetis. Several polymers were investigated, among them, gelatin and sodium alginate. The previous polymers are natural polymers with mucoadhesive properties. Preformulation studies such as atomization head mesh size, flow rate, head temperature, polymer solution viscosity and surface tension were performed. Postformulation characters such as particle size, flowability, surface scan and dissolution profile were evaluated. Finally, the pharmacological activity of certain selected formula was evaluated in streptozotocin-induced diabetic rats. B-90’spray head was 7 µm hole heated to 120 with air flow rate 3.5 mL/min. The viscosity of the solution was less than 11.5 cP with surface tension less than 70.1 dyne/cm. Successfully, discrete, non-aggregated particles and free flowing powders with particle size was less than 2000 nm were obtained. Gelatin and Sodium alginate combination in ratio 1:3 were successfully sustained the in vitro release profile of the drug. Hypoglycemic evaluation of the previous formula showed a significant reduction of blood glucose level over 24 h. In conclusion, mucoadhesive metformin hydrochloride microparticles obtained from B-90 could offer a convenient dosage form with enhanced hypoglycemic activity.Keywords: mucoadhesive, microparticles, metformin hydrochloride, nano-spray dryer
Procedia PDF Downloads 300616 Application of Various Methods for Evaluation of Heavy Metal Pollution in Soils around Agarak Copper-Molybdenum Mine Complex, Armenia
Authors: K. A. Ghazaryan, H. S. Movsesyan, N. P. Ghazaryan
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The present study was aimed in assessing the heavy metal pollution of the soils around Agarak copper-molybdenum mine complex and related environmental risks. This mine complex is located in the south-east part of Armenia, and the present study was conducted in 2013. The soils of the five riskiest sites of this region were studied: surroundings of the open mine, the sites adjacent to processing plant of Agarak copper-molybdenum mine complex, surroundings of Darazam active tailing dump, the recultivated tailing dump of “ravine - 2”, and the recultivated tailing dump of “ravine - 3”. The mountain cambisol was the main soil type in the study sites. The level of soil contamination by heavy metals was assessed by Contamination factors (Cf), Degree of contamination (Cd), Geoaccumulation index (I-geo) and Enrichment factor (EF). The distribution pattern of trace metals in the soil profile according to Cf, Cd, I-geo and EF values shows that the soil is much polluted. Almost in all studied sites, Cu, Mo, Pb, and Cd were the main polluting heavy metals, and this was conditioned by Agarak copper-molybdenum mine complex activity. It is necessary to state that the pollution problem becomes pressing as some parts of these highly polluted region are inhabited by population, and agriculture is highly developed there; therefore, heavy metals can be transferred into human bodies through food chains and have direct influence on public health. Since the induced pollution can pose serious threats to public health, further investigations on soil and vegetation pollution are recommended. Finally, Cf calculating based on distance from the pollution source and the wind direction can provide more reasonable results.Keywords: Agarak copper-molybdenum mine complex, heavy metals, soil contamination, enrichment factor (EF), Armenia
Procedia PDF Downloads 219