Search results for: fluidic cell
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3635

Search results for: fluidic cell

1415 Molecular Characterization and Arsenic Mobilization Properties of a Novel Strain IIIJ3-1 Isolated from Arsenic Contaminated Aquifers of Brahmaputra River Basin, India

Authors: Soma Ghosh, Balaram Mohapatra, Pinaki Sar, Abhijeet Mukherjee

Abstract:

Microbial role in arsenic (As) mobilization in the groundwater aquifers of Brahmaputra river basin (BRB) in India, severely threatened by high concentrations of As, remains largely unknown. The present study, therefore, is a molecular and ecophysiological characterization of an indigenous bacterium strain IIIJ3-1 isolated from As contaminated groundwater of BRB and application of this strain in several microcosm set ups differing in their organic carbon (OC) source and terminal electron acceptors (TEA), to understand its role in As dissolution under aerobic and anaerobic conditions. Strain IIIJ3-1 was found to be a new facultative anaerobic, gram-positive, endospore-forming strain capable of arsenite (As3+) oxidation and dissimilatory arsenate (As5+) reduction. The bacterium exhibited low genomic (G+C)% content (45 mol%). Although, its 16S rRNA gene sequence revealed a maximum similarity of 99% with Bacillus cereus ATCC 14579(T) but the DNA-DNA relatedness of their genomic DNAs was only 49.9%, which remains well below the value recommended to delimit different species. Abundance of fatty acids iC17:0, iC15:0 and menaquinone (MK) 7 though corroborates its taxonomic affiliation with B. cereus sensu-lato group, presence of hydroxy fatty acids (HFAs), C18:2, MK5 and MK6 marked its uniqueness. Besides being highly As resistant (MTC=10mM As3+, 350mM As5+), metabolically diverse, efficient aerobic As3+ oxidizer; it exhibited near complete dissimilatory reduction of As5+ (1 mM). Utilization of various carbon sources with As5+ as TEA revealed lactate to serve as the best electron donor. Aerobic biotransformation assay yielded a lower Km for As3+ oxidation than As5+ reduction. Arsenic homeostasis was found to be conferred by the presence of arr, arsB, aioB, and acr3(1) genes. Scanning electron microscopy (SEM) coupled with energy dispersive X-ray (EDX) analysis of this bacterium revealed reduction in cell size upon exposure to As and formation of As-rich electron opaque dots following growth with As3+. Incubation of this strain with sediment (sterilised) collected from BRB aquifers under varying OC, TEA and redox conditions revealed that the strain caused highest As mobilization from solid to aqueous phase under anaerobic condition with lactate and nitrate as electron donor and acceptor, respectively. Co-release of highest concentrations of oxalic acid, a well known bioweathering agent, considerable fold increase in viable cell counts and SEM-EDX and X-ray diffraction analysis of the sediment after incubation under this condition indicated that As release is consequent to microbial bioweathering of the minerals. Co-release of other elements statistically proves decoupled release of As with Fe and Zn. Principle component analysis also revealed prominent role of nitrate under aerobic and/or anaerobic condition in As release by strain IIIJ3-1. This study, therefore, is the first to isolate, characterize and reveal As mobilization property of a strain belonging to the Bacillus cereus sensu lato group isolated from highly As contaminated aquifers of Brahmaputra River Basin.

Keywords: anaerobic microcosm, arsenic rich electron opaque dots, Arsenic release, Bacillus strain IIIJ3-1

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1414 [Keynote Speech]: Simulation Studies of Pulsed Voltage Effects on Cells

Authors: Jiahui Song

Abstract:

In order to predict or explain a complicated biological process, it is important first to construct mathematical models that can be used to yield analytical solutions. Through numerical simulation, mathematical model results can be used to test scenarios that might not be easily attained in a laboratory experiment, or to predict parameters or phenomena. High-intensity, nanosecond pulse electroporation has been a recent development in bioelectrics. The dynamic pore model can be achieved by including a dynamic aspect and a dependence on the pore population density into pore formation energy equation to analyze and predict such electroporation effects. For greater accuracy, with inclusion of atomistic details, molecular dynamics (MD) simulations were also carried out during this study. Besides inducing pores in cells, external voltages could also be used in principle to modulate action potential generation in nerves. This could have an application in electrically controlled ‘pain management’. Also a simple model-based rate equation treatment of the various cellular bio-chemical processes has been used to predict the pulse number dependent cell survival trends.

Keywords: model, high-intensity, nanosecond, bioelectrics

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1413 Ragging and Sludging Measurement in Membrane Bioreactors

Authors: Pompilia Buzatu, Hazim Qiblawey, Albert Odai, Jana Jamaleddin, Mustafa Nasser, Simon J. Judd

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Membrane bioreactor (MBR) technology is challenged by the tendency for the membrane permeability to decrease due to ‘clogging’. Clogging includes ‘sludging’, the filling of the membrane channels with sludge solids, and ‘ragging’, the aggregation of short filaments to form long rag-like particles. Both sludging and ragging demand manual intervention to clear out the solids, which is time-consuming, labour-intensive and potentially damaging to the membranes. These factors impact on costs more significantly than membrane surface fouling which, unlike clogging, is largely mitigated by the chemical clean. However, practical evaluation of MBR clogging has thus far been limited. This paper presents the results of recent work attempting to quantify sludging and clogging based on simple bench-scale tests. Results from a novel ragging simulation trial indicated that rags can be formed within 24-36 hours from dispersed < 5 mm-long filaments at concentrations of 5-10 mg/L under gently agitated conditions. Rag formation occurred for both a cotton wool standard and samples taken from an operating municipal MBR, with between 15% and 75% of the added fibrous material forming a single rag. The extent of rag formation depended both on the material type or origin – lint from laundering operations forming zero rags – and the filament length. Sludging rates were quantified using a bespoke parallel-channel test cell representing the membrane channels of an immersed flat sheet MBR. Sludge samples were provided from two local MBRs, one treating municipal and the other industrial effluent. Bulk sludge properties measured comprised mixed liquor suspended solids (MLSS) concentration, capillary suction time (CST), particle size, soluble COD (sCOD) and rheology (apparent viscosity μₐ vs shear rate γ). The fouling and sludging propensity of the sludge was determined using the test cell, ‘fouling’ being quantified as the pressure incline rate against flux via the flux step test (for which clogging was absent) and sludging by photographing the channel and processing the image to determine the ratio of the clogged to unclogged regions. A substantial difference in rheological and fouling behaviour was evident between the two sludge sources, the industrial sludge having a higher viscosity but less shear-thinning than the municipal. Fouling, as manifested by the pressure increase Δp/Δt, as a function of flux from classic flux-step experiments (where no clogging was evident), was more rapid for the industrial sludge. Across all samples of both sludge origins the expected trend of increased fouling propensity with increased CST and sCOD was demonstrated, whereas no correlation was observed between clogging rate and these parameters. The relative contribution of fouling and clogging was appraised by adjusting the clogging propensity via increasing the MLSS both with and without a commensurate increase in the COD. Results indicated that whereas for the municipal sludge the fouling propensity was affected by the increased sCOD, there was no associated increased in the sludging propensity (or cake formation). The clogging rate actually decreased on increasing the MLSS. Against this, for the industrial sludge the clogging rate dramatically increased with solids concentration despite a decrease in the soluble COD. From this was surmised that sludging did not relate to fouling.

Keywords: clogging, membrane bioreactors, ragging, sludge

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1412 Effect of Defect Dipoles And Microstructure Engineering in Energy Storage Performance of Co-doped Barium Titanate Ceramics

Authors: Mahmoud Saleh Mohammed Alkathy

Abstract:

Electricity generated from renewable resources may help the transition to clean energy. A reliable energy storage system is required to use this energy properly. To do this, a high breakdown strength (Eb) and a significant difference between spontaneous polarization (Pmax) and remnant polarization (Pr) are required. To achieve this, the defect dipoles in lead free BaTiO3 ferroelectric ceramics are created using Mg2+ and Ni2+ ions as acceptor co-doping in the Ti site. According to the structural analyses, the co-dopant ions were effectively incorporated into the BTO unit cell. According to the ferroelectric study, the co-doped samples display a double hysteresis loop, stronger polarization, and high breakdown strength. The formation of oxygen vacancies and defect dipoles prevent domains' movement, resulting in hysteresis loop pinching. This results in increased energy storage density and efficiency. The defect dipoles mechanism effect can be considered a fascinating technology that can guide the researcher working on developing energy storage for next-generation applications.

Keywords: microstructure, defect, energy storage, effciency

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1411 Fabrication of a Continuous Flow System for Biofilm Studies

Authors: Mohammed Jibrin Ndejiko

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Modern and current models such as flow cell technology which enhances a non-destructive growth and inspection of the sessile microbial communities revealed a great understanding of biofilms. A continuous flow system was designed to evaluate possibility of biofilm formation by Escherichia coli DH5α on the stainless steel (type 304) under continuous nutrient supply. The result of the colony forming unit (CFU) count shows that bacterial attachment and subsequent biofilm formation on stainless steel coupons with average surface roughness of 1.5 ± 1.8 µm and 2.0 ± 0.09 µm were both significantly higher (p ≤ 0.05) than those of the stainless steel coupon with lower surface roughness of 0.38 ± 1.5 µm. These observations support the hypothesis that surface profile is one of the factors that influence biofilm formation on stainless steel surfaces. The SEM and FESEM micrographs of the stainless steel coupons also revealed the attached Escherichia coli DH5α biofilm and dehydrated extracellular polymeric substance on the stainless steel surfaces. Thus, the fabricated flow system represented a very useful tool to study biofilm formation under continuous nutrient supply.

Keywords: biofilm, flowcell, stainless steel, coupon

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1410 The Effect of Geometrical Ratio and Nanoparticle Reinforcement on the Properties of Al-based Nanocomposite Hollow Sphere Structures

Authors: Mostafa Amirjan

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In the present study, the properties of Al-Al2O3 nanocomposite hollow sphere structures were investigated. For this reason, the Al-based nanocomposite hollow spheres with different amounts of nano alumina reinforcement (0-10wt %) and different ratio of thickness to diameter (t/D: 0.06-0.3) were prepared via a powder metallurgy method. Then, the effect of mentioned parameters was studied on physical and quasi static mechanical properties of their related prepared structures (open/closed cell) such as density, hardness, strength and energy absorption. It was found that as the t/D ratio increases the relative density, compressive strength and energy absorption increase. The highest values of strength and energy absorption were obtained from the specimen with 5 wt. % of nanoparticle reinforcement, t/D of 0.3 (t=1 mm, D=400µm) as 22.88 MPa and 13.24 MJ/m3, respectively. The moderate specific strength of prepared composites in the present study showed the good consistency with the properties of others low carbon steel composite with similar structure.

Keywords: hollow sphere structure foam, nanocomposite, thickness and diameter (t/D ), powder metallurgy

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1409 Inactivation of Listeria innocua ATCC 33092 by Gas-Phase Plasma Treatment

Authors: Z. Herceg, V. Stulic, T. Vukusic, A. Rezek Jambrak

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High voltage electrical discharge plasmas are new nonthermal developing techniques used for water decontamination. To the full understanding of cell inactivation mechanisms, this study brings inactivation, recovery and cellular leakage of L. innocua cells before and after the treatment. Bacterial solution (200 mL) of L. innocua was treated in a glass reactor with a point-to-plate electrode configuration (high voltage electrode-titanium wire, was in the gas phase and grounded electrode was in the liquid phase). Argon was injected into the headspace of the reactor at the gas flow of 5 L/min. Frequency of 60, 90 and 120 Hz, time of 5 and 10 min, positive polarity and conductivity of media of 100 µS/cm were chosen to define listed parameters. With a longer treatment time inactivation was higher as well as the increase in cellular leakage. Despite total inactivation recovery of cells occurred probably because of a high leakage of proteins, compared to lower leakage of nucleic acids (DNA and RNA). In order to define mechanisms of inactivation further research is needed.

Keywords: Listeria innocua ATCC 33092, inactivation, gas phase plasma, cellular leakage, recovery of cells

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1408 Flexural Response of Glass Fiber Reinforced Polymer Sandwich Panels with 3D Woven Honeycomb Core

Authors: Elif Kalkanli, Constantinos Soutis

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The use of textile preform in the advanced fields including aerospace, automotive and marine has exponentially grown in recent years. These preforms offer excellent advantages such as being lightweight and low-cost, and also, their suitability for creating different fiber architectures with different materials whilst improved mechanical properties in certain aspects. In this study, a novel honeycomb core is developed by a 3Dweaving process. The assembly of the layers is achieved thanks to innovative weaving design. Polyester yarn is selected for the 3D woven honeycomb core (3DWHC). The core is used to manufacture a sandwich panel with 2x2 twill glass fiber composite face sheets. These 3DWHC sandwich panels will be tested in three-point bending. The in-plane and out-of-plane (through-the-thickness) mechanical response of the core will be examined as a function of cell size in addition to the flexural response of the sandwich panel. The failure mechanisms of the core and the sandwich skins will be reported in addition to flexural strength and stiffness. Possible engineering applications will be identified.

Keywords: 3D woven, assembly, failure modes, honeycomb sandwich panel

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1407 Interaction of Histone H1 with Chromatin-associated Protein HMGB1 Studied by Microscale Thermophoresis

Authors: Michal Štros, Eva Polanská, Šárka Pospíšilová

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HMGB1 is an architectural protein in chromatin, acting also as a signaling molecule outside the cell. Recent reports from several laboratories provided evidence that a number of both the intracellular and extracellular functions of HMGB1 may depend on redox-sensitive cysteine residues of the protein. MALDI-TOF analysis revealed that mild oxidization of HMGB1 resulted in a conformational change of the protein due to formation of an intramolecular disulphide bond by opposing Cys23 and Cys45 residues. We have demonstrated that redox state of HMGB1 could significantly modulate the ability of the protein to bind and bend DNA. We have also shown that reduced HMGB1 could easily displace histone H1 from DNA, while oxidized HMGB1 had limited capacity for H1 displacement. Using microscale thermophoresis (MST) we have further studied mechanism of HMGB1 interaction with histone H1 in free solution or when histone H1 was bound to DNA. Our MST analysis indicated that reduced HMGB1 exhibited in free solution > 1000 higher affinity of for H1 (KD ~ 4.5 nM) than oxidized HMGB1 (KD <10 M). Finally, we present a novel mechanism for the HMGB1-mediated modulation of histone H1 binding to DNA.

Keywords: HMGB1, histone H1, redox state, interaction, cross-linking, DNA bending, DNA end-joining, microscale thermophoresis

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1406 Effect of Copper Ions Doped-Hydroxyapatite 3D Fiber Scaffold

Authors: Adil Elrayah, Jie Weng, Esra Suliman

Abstract:

The mineral in human bone is not pure stoichiometric calcium phosphate (Ca/P) as it is partially substituted by in organic elements. In this study, the copper ions (Cu2+) substituted hydroxyapatite (CuHA) powder has been synthesized by the co-precipitation method. The CuHA powder has been used to fabricate CuHA fiber scaffolds by sol-gel process and the following sinter process. The resulted CuHA fibers have slightly different microstructure (i.e. porosity) compared to HA fiber scaffold, which is denser. The mechanical properties test was used to evaluate CuHA, and the results showed decreases in both compression strength and hardness tests. Moreover, the in vitro used endothelial cells to evaluate the angiogenesis of CuHA. The result illustrated that the viability of endothelial cell on CuHA fiber scaffold surfaces tends to antigenic behavior. The results obtained with CuHA scaffold give this material benefit in biological applications such as antimicrobial, antitumor, antigens, compacts, filling cavities of the tooth and for the deposition of metal implants anti-tumor, anti-cancer, bone filler, and scaffold.

Keywords: fiber scaffold, copper ions, hydroxyapatite, in vitro, mechanical property

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1405 Interaction between Unsteady Supersonic Jet and Vortex Rings

Authors: Kazumasa Kitazono, Hiroshi Fukuoka, Nao Kuniyoshi, Minoru Yaga, Eri Ueno, Naoaki Fukuda, Toshio Takiya

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The unsteady supersonic jet formed by a shock tube with a small high-pressure chamber was used as a simple alternative model for pulsed laser ablation. Understanding the vortex ring formed by the shock wave is crucial in clarifying the behavior of unsteady supersonic jet discharged from an elliptical cell. Therefore, this study investigated the behavior of vortex rings and a jet. The experiment and numerical calculation were conducted using the schlieren method and by solving the axisymmetric two-dimensional compressible Navier–Stokes equations, respectively. In both, the calculation and the experiment, laser ablation is conducted for a certain duration, followed by discharge through the exit. Moreover, a parametric study was performed to demonstrate the effect of pressure ratio on the interaction among vortex rings and the supersonic jet. The interaction between the supersonic jet and the vortex rings increased the velocity of the supersonic jet up to the magnitude of the velocity at the center of the vortex rings. The interaction between the vortex rings increased the velocity at the center of the vortex ring.

Keywords: computational fluid dynamics, shock-wave, unsteady jet, vortex ring

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1404 Controlling the Fluid Flow in Hydrogen Fuel Cells through Material Porosity Designs

Authors: Jamal Hussain Al-Smail

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Hydrogen fuel cells (HFCs) are environmentally friendly, energy converter devices that convert the chemical energy of the reactants (oxygen and hydrogen) to electricity through electrochemical reactions. The level of the electricity production of HFCs mainly increases depending on the oxygen distribution in the HFC’s cathode gas diffusion layer (GDL). With a constant porosity of the GDL, the electrochemical reaction can have a great variation that reduces the cell’s productivity and stability. Our findings bring a methodology in finding porosity designs of the diffusion layer to improve the oxygen distribution such that it results in a stable oxygen-hydrogen reaction. We first introduce a mathematical model involving the mass and momentum transport equations, in which a porosity function of the GDL is incorporated as a control for the fluid flow. We then derive numerical methods for solving the mathematical model. In conclusion, we present our numerical results to show how to design the GDL porosity to result in a uniform oxygen distribution.

Keywords: fuel cells, material porosity design, mathematical modeling, porous media

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1403 Synthesis of Brominated Pyrazoline Derived from Chalcone and Its Antimicrobial Activity

Authors: Annisa I. Reza, Jasril Karim

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Despite the availability of antimicrobial agents in the market, the urge to study and find other chemical compounds with the better potential of replacing them still tempting the scientists. This experiment is in the aim to explore a novel brominated pyrazoline ring which was made from intermediate chalcone as a candidate to answer the challenge. Using green chemistry approach by microwave irradiation from domestic oven, both known chalcone and 5-(2-bromophenyl)-3-(naphthalen-1-yl)-4,5-dihydro-1H-pyrazole were successfully synthesized. Pyrazoline’s structure was confirmed based on UV, IR, ¹H-NMR, ¹³C-NMR and MS and together with its intermediate were examined against some microorganisms (Bacillus subtilis, Escherichia coli, and Candida albicans) under agar diffusion method. The results collected during experiment revealed that both tested compounds showed weak activity on B.subtilis which was proven by a zone of inhibitions, while there was no zone of inhibitions observed in E. coli and C. albicans. This is suggested because of the bulky structure around pyrazoline could not provide the main ring to interact with microbial’s cell wall. The study shows that the proposed compound had the low capability as a promising antimicrobial agent, yet it still enriches the information about pyrazoline ring.

Keywords: antimicrobial, chalcone, microwave irradiation, pyrazoline

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1402 Haematological Alterations in Anemic Bali Cattle Raised in Semi-Intensive Husbandry System

Authors: Jully Handoko, B. Kuntoro, E. Saleh, Sadarman

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Most farmers in Bangkinang Seberang sub district raise Bali cattle in semi-intensive husbandry system. The farmers believe that raising such a way is economical and quite effective. The farmers do not need to provide forage and plant feed crops. Furthermore, the raising method is considered not to interfere with the main job. Screening for anemia in Bali cattle of Bangkinang Seberang subdistrict, Kampar regency, Riau, Indonesia, had been conducted. The aim of the study was to analyze hematological alterations in the anemic Bali cattle. A number of 75 Bali cattle were screened for anemia on the basis of Hemoglobin (Hb) concentration. The other hematological parameters that were measured including packed cell volume (PCV), total erythrocyte count (TEC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC). The screening showed that 18 (24.00%) of Bali cattle were anemic. Levels of Hb, PCV, TEC, MCV, MCH and MCHC in anemic Bali cattle were 7.15±1.61 g/dl, 21.15±4.16%, 3.72±1.10x106/µl, 52.75±4.13 fl, 17.31±1.86 pg and 32.77±1.69 g/dl respectively. Hematological values of Hb, PCV, TEC, MCV, MCH and MCHC were significantly (p < 0.05) lower in anemic Bali cattle compared to non-anemic Bali cattle.

Keywords: anemia, Bali cattle, alterations, hematology

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1401 Empowering Rangatahi: Amplifying Youth Voices on Smartphone and Social Media Use in Aotearoa New Zealand

Authors: Melissa L Gould

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The uptick in social media users during the COVID-19 lockdowns has accelerated concerns about cellphone addiction, cyberbullying, and exposure to harmful content, particularly mis- and disinformation and extremist content. The validity of these concerns is synthesized for media technologists to expose the strategies behind social media and search platform technology and explain why they restrict their children from using it. Banning cell phones in schools, increasing age limits on social media accounts, and putting warning labels on social media are some of the solutions proposed to protect young people from smartphones and social media. Largely missing from these conversations are the voices of young people (rangatahi). Instead, their lived experiences are being told and managed by adults. This presentation will outline my research that amplified the voices and lived experiences of young people by positioning them as experts. Using The Social Dilemma as a discussion prompt, the focus groups of rangatahi in Aotearoa, New Zealand, provide a space for young people to articulate their own lived experiences and respond to the dominant narratives on their generation's use of smartphones and social media.

Keywords: social media, smart phones, young people, social dilemma

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1400 Repurposing of Crystalline Solar PV For Sodium Silicate Production

Authors: Lawal Alkasim, Clement M. Gonah, Zainab S. Aliyu

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This work is focus on recovering silicon form photovoltaic cells and repurposing it toward the use in glass, ceramics or glass ceramics as it is made up of silicon material. Silicon is the main back-bone and responsible for the thermodynamic properties of glass, ceramics and glass ceramics materials. Antireflection silicon is soluble in hot alkali. Successfully the recovered material composed of silicon and silicon nitride of the A.R, with a small amount of silver, Aluminuim, lead & copper in the sunshine of crystalline/non-crystalline silicon solar cell. Aquaregia is used to remove the silver, Aluminium, lead & copper. The recovered material treated with hot alkali highly concentrated to produce sodium silicate, which is an alkali silicate glass (water glass). This type of glass is produced through chemical process, unlike other glasses that are produced through physical process of melting and non-crystalline solidification. It has showed a property of being alkali silicate glass from its solubility in water and insoluble in alcohol. The XRF analysis shows the presence of sodium silicate.

Keywords: unrecyclable solar PV, crystalline silicon, hot conc. alkali, sodium silicate

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1399 Exploiting the Tumour Microenvironment in Order to Optimise Sonodynamic Therapy for Cancer

Authors: Maryam Mohammad Hadi, Heather Nesbitt, Hamzah Masood, Hashim Ahmed, Mark Emberton, John Callan, Alexander MacRobert, Anthony McHale, Nikolitsa Nomikou

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Sonodynamic therapy (SDT) utilises ultrasound in combination with sensitizers, such as porphyrins, for the production of cytotoxic reactive oxygen species (ROS) and the confined ablation of tumours. Ultrasound can be applied locally, and the acoustic waves, at frequencies between 0.5-2 MHz, are transmitted efficiently through tissue. SDT does not require highly toxic agents, and the cytotoxic effect only occurs upon ultrasound exposure at the site of the lesion. Therefore, this approach is not associated with adverse side effects. Further highlighting the benefits of SDT, no cancer cell population has shown resistance to therapy-triggered ROS production or their cytotoxic effects. This is particularly important, given the as yet unresolved issues of radiation and chemo-resistance, to the authors’ best knowledge. Another potential future benefit of this approach – considering its non-thermal mechanism of action – is its possible role as an adjuvant to immunotherapy. Substantial pre-clinical studies have demonstrated the efficacy and targeting capability of this therapeutic approach. However, SDT has yet to be fully characterised and appropriately exploited for the treatment of cancer. In this study, a formulation based on multistimulus-responsive sensitizer-containing nanoparticles that can accumulate in advanced prostate tumours and increase the therapeutic efficacy of SDT has been developed. The formulation is based on a polyglutamate-tyrosine (PGATyr) co-polymer carrying hematoporphyrin. The efficacy of SDT in this study was demonstrated using prostate cancer as the translational exemplar. The formulation was designed to respond to the microenvironment of advanced prostate tumours, such as the overexpression of the proteolytic enzymes, cathepsin-B and prostate-specific membrane antigen (PSMA), that can degrade the nanoparticles, reduce their size, improving both diffusions throughout the tumour mass and cellular uptake. The therapeutic modality was initially tested in vitro using LNCaP and PC3 cells as target cell lines. The SDT efficacy was also examined in vivo, using male SCID mice bearing LNCaP subcutaneous tumours. We have demonstrated that the PGATyr co-polymer is digested by cathepsin B and that digestion of the formulation by cathepsin-B, at tumour-mimicking conditions (acidic pH), leads to decreased nanoparticle size and subsequent increased cellular uptake. Sonodynamic treatment, at both normoxic and hypoxic conditions, demonstrated ultrasound-induced cytotoxic effects only for the nanoparticle-treated prostate cancer cells, while the toxicity of the formulation in the absence of ultrasound was minimal. Our in vivo studies in immunodeficient mice, using the hematoporphyrin-containing PGATyr nanoparticles for SDT, showed a 50% decrease in LNCaP tumour volumes within 24h, following IV administration of a single dose. No adverse effects were recorded, and body weight was stable. The results described in this study clearly demonstrate the promise of SDT to revolutionize cancer treatment. It emphasizes the potential of this therapeutic modality as a fist line treatment or in combination treatment for the elimination or downstaging of difficult to treat cancers, such as prostate, pancreatic, and advanced colorectal cancer.

Keywords: sonodynamic therapy, nanoparticles, tumour ablation, ultrasound

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1398 Phylogenetic Analysis and a Review of the History of the Accidental Phytoplankter, Phaeodactylum tricornutum Bohlin (Bacillariophyta)

Authors: Jamal S. M. Sabir, Edward C. Theriot, Schonna R. Manning, Abdulrahman L. Al-Malki, Mohammad, Mumdooh J. Sabir, Dwight K. Romanovicz, Nahid H. Hajrah, Robert K. Jansen, Matt P. Ashworth

Abstract:

The diatom Phaeodactylum tricornutum has been used as a model for cell biologists and ecologists for over a century. We have incorporated several new raphid pennates into a three-gene phylogenetic dataset (SSU, rbcL, psbC), and recover Gomphonemopsis sp. as sister to P. tricornutum with 100% BS support. This is the first time a close relative has been identified for P. tricornutum with robust statistical support. We test and reject a succession of hypotheses for other relatives. Our molecular data are statistically significantly incongruent with placement of either or both species among the Cymbellales, an order of diatoms with which both have been associated. We believe that further resolution of the phylogenetic position of P. tricornutum will rely more on increased taxon sampling than increased genetic sampling. Gomphonemopsis is a benthic diatom, and its phylogenetic relationship with P. tricornutum is congruent with the hypothesis that P. tricornutum is a benthic diatom with specific adaptations that lead to active recruitment into the plankton. We hypothesize that other benthic diatoms are likely to have similar adaptations and are not merely passively recruited into the plankton.

Keywords: benthic, diatoms; ecology, Phaeodactylum tricornutum, phylogeny, tychoplankton

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1397 Fermentation with Lactobacillus plantarum CK10 Enhanced Antioxidant Activity of Blueberry Puree

Authors: So Yae Koh, YeonWoo Song, Ji-Yeon Ryu, Jeong Yong Moon, Somi Kim Cho

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Blueberry, a perennial shrub, is one of the most popular fruits due to its flavor and strong free radical scavenging properties. In this study, the blueberry puree was fermented by Lactobacillus plantarum CK10 and the antioxidant activities of fermentation products were examined. Various conditions with different supplements (5% sucrose or 10% skim milk) were evaluated for fermentation efficiency and the effects on antioxidant properties. The viable cell count of lactic acid bacteria, pH, total phenolic compounds and flavonoids contents were measured after 7 days of fermentation. DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS [2,2’-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)] radical scavenging activities were highly enhanced compared to non-fermented blueberry puree after fermentation. Interestingly, the antioxidant activities were greatly increased in the fermentation of blueberry puree alone without supplements. The present results indicate that the blueberry puree fermented by Lactobacillus plantarum CK10 could be used as a potential source of natural antioxidants and these findings will facilitate the utilization of blueberry as a resource for food additive.

Keywords: antioxidant activity, blueberry, lactobacillus plantarum CK10, fermentation

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1396 Investigation of the Possible Beneficial and Protective Effects of an Ethanolic Extract from Sarcopoterium spinosum Fruits

Authors: Hawraa Zbeeb, Hala Khalifeh, Mohamad Khalil, Francesca Storace, Francesca Baldini, Giulio Lupidi, Laura Vergani

Abstract:

Sarcopoterium spinosum, a widely distributed spiny shrub belonging to the Rosaceae family, is rich in essential and beneficial constituents. In fact, S. spinosum fruits and roots are traditionally used as herbal medicine in the eastern Mediterranean landscape, and this shrub is mentioned as a medicinal plant in a large number of ethnobotanical surveys. Aqueous root extracts from S. spinosum are used by traditional medicinal practitioners for weight loss treatment of diabetes and pain. Moreover, the anti-diabetic activity of S. spinosum root extract has been reported in different studies, but the beneficial effects of aerial parts, especially fruits, have not been elucidated yet. The aim of the present study was to investigate the in vitro antioxidant and lipid-lowering properties of an ethanolic extract from S. spinosum fruits using both hepatic (FaO) and endothelial (HECV) cells in an attempt to evaluate its possible employment as a nutraceutical supplement. First of all, in vitro spectrophotometric assays were employed to characterize the extract. The total phenol content (TPC) was evaluated by Folin–Ciocalteu spectrophotometric method and the radical scavenging activity was tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. After that, the beneficial effects of the extract were tested on cells. FaO cells treated for 3 hours with 0.75 mM oleate/palmitate mix (1:2 molar ratio) mimic in vitro a moderate hepato-steatosis. HECV cells exposed for 1 hour to 100 µM H₂O₂ mimic an oxidative insult leading to oxidative stress conditions. After the metabolic and oxidative insult, both cell lines were treated with increasing concentrations of the S. spinosum extract (1, 10, 25 µg/mL) for 24 hours. The results showed the S. spinosum ethanolic extract is rather rich in phenols (TPC of 18.6 mgGAE/g dry extracts). Moreover, the extract showed a good scavenging ability in vitro (IC₅₀ 15.9 µg/ml and 10.9 µg/ml measured by DPPH and ABTS assays, respectively). When the extract was tested on cells, the results showed that it could ameliorate some markers of cell dysfunction. The three concentrations of the extract led to a significant decrease in the intracellular triglyceride (TG) content in steatotic FaO cells measured by spectrophotometric assay. On the other hand, HECV cells treated with increasing concentrations of the extract did not result in a significant decrease in both lipid peroxidation measured by the Thiobarbituric Acid Reactive Substances (TBARS) assay, and in reactive oxygen species (ROS) production measured by fluorometric analysis after DCF staining. Interestingly, the ethanolic extract was able to accelerate the wound repair of confluent HECV cells with respect to H₂O₂-insulted cells as measured by T-scratch assay. Taken together, these results seem to indicate that the ethanol extract from S. spinosum fruits is rich in phenol compounds and plays considerable lipid-lowering activity in vitro on steatotic hepatocytes and accelerates wound healing repair on endothelial cells. In light of that, the ethanolic extract from S. spinosum fruits could be a potential candidate for nutraceutical applications.

Keywords: antioxidant activity, ethanolic extract, lipid-lowering activity, phenolic compounds, Sarcopoterium spinosum fruits

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1395 Role of Long Noncoding RNA HULC on Colorectal Carcinoma Progression through Epigenetically Repressing NKD2 Expression

Authors: Shu-Jun Li, Cheng-Cao Sun, De-Jia Li

Abstract:

Recently, long noncoding RNAs (lncRNAs) have been emerged as crucial regulators of human diseases and prognostic markers in numerous of cancers, including colorectal carcinoma (CRC). Here, we identified an oncogenetic lncRNA HULC, which may promote colorectal tumorigenesis. HULC has been found to be up-regulated and acts as oncogene in gastric cancer and hepatocellular carcinoma, but its expression pattern, biological function and underlying mechanism in CRC is still undetermined. Here, we reported that HULC expression is also over-expressed in CRC, and its increased level is associated with poor prognosis and shorter survival. Knockdown of HULC impaired CRC cells proliferation, migration and invasion, facilitated cell apoptosis in vitro, and inhibited tumorigenicity of CRC cells in vivo. Mechanistically, RNA immunoprecipitation (RIP) and RNA pull-down experiment demonstrated that HULC could simultaneously interact with EZH2 to repress underlying targets NKD2 transcription. In addition, rescue experiments determined that HULC oncogenic function is partly dependent on repressing NKD2. Taken together, our findings expound how HULC over-expression endows an oncogenic function in CRC.

Keywords: long noncoding RNA, HULC, NKD2, colorectal carcinoma, proliferation, apoptosis

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1394 3D Electromagnetic Mapping of the Signal Strength in Long Term Evolution Technology in the Livestock Department of ESPOCH

Authors: Cinthia Campoverde, Mateo Benavidez, Victor Arias, Milton Torres

Abstract:

This article focuses on the 3D electromagnetic mapping of the intensity of the signal received by a mobile antenna within the open areas of the Department of Livestock of the Escuela Superior Politecnica de Chimborazo (ESPOCH), located in the city of Riobamba, Ecuador. The transmitting antenna belongs to the mobile telephone company ”TUENTI”, and is analyzed in the 2 GHz bands, operating at a frequency of 1940 MHz, using Long Term Evolution (LTE). Power signal strength data in the area were measured empirically using the ”Network Cell Info” application. A total of 170 samples were collected, distributed in 19 concentric circles around the base station. 3 campaigns were carried out at the same time, with similar traffic, and average values were obtained at each point, which varies between -65.33 dBm to -101.67 dBm. Also, the two virtualization software used are Sketchup and Unreal. Finally, the virtualized environment was visualized through virtual reality using Oculus 3D glasses, where the power levels are displayed according to a range of powers.

Keywords: reception power, LTE technology, virtualization, virtual reality, power levels

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1393 Studying the Anti-Cancer Effects of Thymoquinone on Tumor Cells Through Natural Killer Cells Activity

Authors: Nouf A. Aldarmahi, Nesrin I. Tarbiah, Nuha A. Alkhattabi, Huda F. Alshaibi

Abstract:

Nigella sativa which is known as dark cumin is a well-known example for a widely applicable herbal medicine. Nigella sativa can be effective in a variety of diseases such as hypertension, diabetes, bronchitis, gastrointestinal upset, and cancer. The anticancer effect of Nigella sativa appeared to be mediated by immune-modulatory effect through stimulating human natural killer (NK) cells. This is a type of lymphocytes which is part of the innate immunity, also known as the first line of defense in the body against pathogens. This study investigated the effect of thymoquinone as a major component of Nigella sativa on the molecular cytotoxic pathway of NK cell and the role of thymoquinone therapeutic effect on NK cells. NK cells were cultured with breast tumor cells in different ways and cultured media was collected and the concentration of perforin, granzyme B and interferon-α were measured by ELISA. The cytotoxic effect of NK cells on breast tumor cells was enhanced in the presence of thymoquinone, with increased activity of perforin in NK cells. This improved anticancer effect of thymoquinone on breast cancer cells.

Keywords: breast cancer, cancer cells, natural killer cells, thymoquinone

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1392 Construction of a Desktop Arduino Controlled Propeller Test Stand

Authors: Brian Kozak, Ryan Ferguson, Evan Hockeridge

Abstract:

Aerospace engineering and aeronautical engineering students studying propulsion often learn about propellers and their importance in aviation propulsion. In order to reinforce concepts introduced in the classroom, laboratory projects are used. However, to test a full scale propeller, an engine mounted on a test stand must be used. This engine needs to be enclosed in a test cell for appropriated safety requirements, is expensive to operate, and requires a significant amount of time to change propellers. In order to decrease costs and time requirements, the authors designed and built an electric motor powered desktop Arduino controlled test stand. This test stand is used to enhance student understanding of propeller size and pitch on thrust. The test stand can accommodate propellers up to 25 centimeters in diameter. The code computer allowed for the motor speed to be increased or decreased by 1% per second. Outputs that are measured are thrust, motor rpm, amperes, voltage, and motor temperature. These data are exported as a .CVS file and can be imported into a graphing program for data analysis.

Keywords: Arduino, Laboratory Project, Test stand, Propeller

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1391 Assessment of Mammary Gland Immunity and Therapeutic Potential of Topical Herbal Gel against Bovine Subclinical Mastitis

Authors: Mukesh N. Kher, Anju P. Kunjadia, Dev S. Nauriyal, Chaitanya G. Joshi, Navin R. Sheth, Vaibhav D. Bhatt

Abstract:

In-vivo immunotherapeutic potential on cytokines production and antibacterial activity of a topical herbal gel was evaluated in two breeds of cattle in bovine subclinical mastitis. The response to treatment was evaluated by enumerating somatic cell count (SCC), determining total bacterial count and studying the expression of different cytokines like (interleukin 6, 8, 12, GMCSF, interferon–γ and TNF‑α). The pre‑ and post‑treatment SCC in mastitic quarters did not differ statistically-significantly. However, total bacterial count declined significantly from day 0 onwards in both the breeds. Significant differences (P < 0.01) were observed in all types of cytokines production on day 0, 5, and 21 post last treatments in both the breeds. The comparison of cytokine expression profiles between crossbred and Gir cattle affirmed a significant difference in expression of IL-6 and TNF-α. The topical herbal gel showed immunomodulatory and antimicrobial activities in subclinical mastitis, and therefore the work supports its use as substitute herbal therapy against subclinical mastitis in bovines.

Keywords: antibacterial activity, immunomodulation, herbal gel, subclinical mastitis

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1390 EGFR Signal Induced-Nuclear Translocation of Beta-catenin and PKM2 Promotes HCC Malignancy and Indicates Early Recurrence After Curative Resection

Authors: Fangtian Fan, Zhaoguo Liu, Yin Lu

Abstract:

Early recurrence (ER) (< 1 year) after liver resection is one of the most important factors that impacts the prognosis of patients with hepatocellular carcinoma (HCC). However, the molecular mechanisms and predictive indexes of ER after curative resection remain largely unknown. The present study aimed to exploit the role of EGFR signaling in EMT and early recurrence of HCC after curative resection and elucidate the molecular mechanisms. Our results showed that nuclear beta-catenin / PKM2 was a independent predictor of early recurrence after curative resection in EGFR-overexpressed HCC. Mechanistic investigation indicated that nuclear accumulation of beta-catenin and PKM2 induced by EGFR signal promoted HCC cell invasion and proliferation, which were required for early recurrence of HCC. These effects were mediated by PI3K/AKT and ERK pathways rather than the canonical Wnt signaling. In conclusions, EGFR signal induced-nuclear translocation of beta-catenin and PKM2 promotes HCC malignancy and indicates early recurrence after curative resection.

Keywords: beta-catenin, early recurrence, hepatocellular carcinoma, malignancy, PKM2

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1389 An Investigation on the Suitability of Dual Ion Beam Sputtered GMZO Thin Films: For All Sputtered Buffer-Less Solar Cells

Authors: Vivek Garg, Brajendra S. Sengar, Gaurav Siddharth, Nisheka Anadkat, Amitesh Kumar, Shailendra Kumar, Shaibal Mukherjee

Abstract:

CuInGaSe (CIGSe) is the dominant thin film solar cell technology. The band alignment of Buffer/CIGSe interface is one of the most crucial parameters for solar cell performance. In this article, the valence band offset (VBOff) and conduction band offset (CBOff) values of Cu(In0.70Ga0.30)Se/ 1 at.% Ga: Mg0.25Zn0.75O (GMZO) heterojunction, grown by dual ion beam sputtering system (DIBS), are calculated to understand the carrier transport mechanism at the heterojunction for the realization of all sputtered buffer-less solar cells. To determine the valence band offset (VBOff), ∆E_V at GMZO/CIGSe heterojunction interface, the standard method based on core-level photoemission is utilized. The value of ∆E_V can be evaluated by considering common core-level peaks. In our study, the values of (Valence band onset)VBOn, obtained by linear extrapolation method for GMZO and CIGSe films are calculated to be 2.86 and 0.76 eV. In the UPS spectra peak positions of Se 3d is observed in UPS spectra at 54.82 and 54.7 eV for CIGSe film and GMZO/CIGSe interface respectively, while the peak position of Mg 2p is observed at 50.09 and 50.12 eV for GMZO and GMZO/CIGSe interface respectively. The optical band gap of CIGSe and GMZO are obtained from absorption spectra procured from spectroscopic ellipsometry are 1.26 and 3.84 eV respectively. The calculated average values of ∆E_v and ∆E_C are estimated to be 2.37 and 0.21 eV, respectively, at room temperature. The calculated positive conduction band offset termed as a spike at the absorber junction is the required criterion for the high-efficiency solar cells for the efficient charge extraction from the junction. So we can conclude that the above study confirms GMZO thin films grown by the dual ion beam sputtering system are the suitable candidate for the CIGSe thin films based ultra-thin buffer-less solar cells. We investigated the band-offset properties at the GMZO/CIGSe heterojunction to verify the suitability of the GMZO for the realization of the buffer-less solar cells. The calculated average values of ∆E_V and ∆E_C are estimated to be 2.37 and 0.21 eV, respectively, at room temperature. The calculated positive conduction band offset termed as a spike at the absorber junction is the required criterion for the high-efficiency solar cells for the efficient charge extraction from the junction. So we can conclude that the above study confirms GMZO thin films grown by the dual ion beam sputtering system are the suitable candidate for the CIGSe thin films based ultra-thin buffer-less solar cells. Acknowledgment: We are thankful to DIBS, EDX, and XRD facility equipped at Sophisticated Instrument Centre (SIC) at IIT Indore. The authors B.S.S and A.K acknowledge CSIR and V.G acknowledge UGC, India for their fellowships. B.S.S is thankful to DST and IUSSTF for BASE Internship Award. Prof. Shaibal Mukherjee is thankful to DST and IUSSTF for BASE Fellowship and MEITY YFRF award. This work is partially supported by DAE BRNS, DST CERI, and DST-RFBR Project under India-Russia Programme of Cooperation in Science and Technology. We are thankful to Mukul Gupta for SIMS facility equipped at UGC-DAE Indore.

Keywords: CIGSe, DIBS, GMZO, solar cells, UPS

Procedia PDF Downloads 257
1388 On the Utility of Bidirectional Transformers in Gene Expression-Based Classification

Authors: Babak Forouraghi

Abstract:

A genetic circuit is a collection of interacting genes and proteins that enable individual cells to implement and perform vital biological functions such as cell division, growth, death, and signaling. In cell engineering, synthetic gene circuits are engineered networks of genes specifically designed to implement functionalities that are not evolved by nature. These engineered networks enable scientists to tackle complex problems such as engineering cells to produce therapeutics within the patient's body, altering T cells to target cancer-related antigens for treatment, improving antibody production using engineered cells, tissue engineering, and production of genetically modified plants and livestock. Construction of computational models to realize genetic circuits is an especially challenging task since it requires the discovery of the flow of genetic information in complex biological systems. Building synthetic biological models is also a time-consuming process with relatively low prediction accuracy for highly complex genetic circuits. The primary goal of this study was to investigate the utility of a pre-trained bidirectional encoder transformer that can accurately predict gene expressions in genetic circuit designs. The main reason behind using transformers is their innate ability (attention mechanism) to take account of the semantic context present in long DNA chains that are heavily dependent on the spatial representation of their constituent genes. Previous approaches to gene circuit design, such as CNN and RNN architectures, are unable to capture semantic dependencies in long contexts, as required in most real-world applications of synthetic biology. For instance, RNN models (LSTM, GRU), although able to learn long-term dependencies, greatly suffer from vanishing gradient and low-efficiency problem when they sequentially process past states and compresses contextual information into a bottleneck with long input sequences. In other words, these architectures are not equipped with the necessary attention mechanisms to follow a long chain of genes with thousands of tokens. To address the above-mentioned limitations, a transformer model was built in this work as a variation to the existing DNA Bidirectional Encoder Representations from Transformers (DNABERT) model. It is shown that the proposed transformer is capable of capturing contextual information from long input sequences with an attention mechanism. In previous works on genetic circuit design, the traditional approaches to classification and regression, such as Random Forrest, Support Vector Machine, and Artificial Neural Networks, were able to achieve reasonably high R2 accuracy levels of 0.95 to 0.97. However, the transformer model utilized in this work, with its attention-based mechanism, was able to achieve a perfect accuracy level of 100%. Further, it is demonstrated that the efficiency of the transformer-based gene expression classifier is not dependent on the presence of large amounts of training examples, which may be difficult to compile in many real-world gene circuit designs.

Keywords: machine learning, classification and regression, gene circuit design, bidirectional transformers

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1387 Alternating Electric fields-Induced Senescence in Glioblastoma

Authors: Eun Ho Kim

Abstract:

Innovations have conjured up a mode of treating GBM cancer cells in the newly diagnosed patients in a period of 4.9 months at an improved median OS, which brings along only a few minor side effects in the phase III of the clinical trial. This mode has been termed the Alternating Electric Fields (AEF). The study at hand is aimed at determining whether the AEF treatment is beneficial in sensitizing the GBM cancer cells through the process of increasing the AEF –induced senescence. The methodology to obtain the findings for this research ranged across various components, such as obtaining and testing SA-β-gal staining, flow cytometry, Western blotting, morphology, and Positron Emission Tomography (PET) / Computed Tomography (CT), immunohistochemical staining and microarray. The number of cells that displayed a senescence-specific morphology and positive SA-ß-Gal activity gradually increased up to 5 days. These results suggest that p16, p21 and p27 are essential regulators of AEF -induced senescence via NF-κB activation. The results showed that the AEF treatment is functional in enhancing the AEF –induced senescence in the GBM cells via an apoptosis- independent mechanism. This research concludes that this mode of treatment is a trustworthy protocol that can be effectively employed to overcome the limitations of the conventional mode of treatment on GBM.

Keywords: alternating electric fields, senescence, glioblastoma, cell death

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1386 Optimizing Heavy-Duty Green Hydrogen Refueling Stations: A Techno-Economic Analysis of Turbo-Expander Integration

Authors: Christelle Rabbat, Carole Vouebou, Sary Awad, Alan Jean-Marie

Abstract:

Hydrogen has been proven to be a viable alternative to standard fuels as it is easy to produce and only generates water vapour and zero carbon emissions. However, despite the hydrogen benefits, the widespread adoption of hydrogen fuel cell vehicles and internal combustion engine vehicles is impeded by several challenges. The lack of refueling infrastructures remains one of the main hindering factors due to the high costs associated with their design, construction, and operation. Besides, the lack of hydrogen vehicles on the road diminishes the economic viability of investing in refueling infrastructure. Simultaneously, the absence of accessible refueling stations discourages consumers from adopting hydrogen vehicles, perpetuating a cycle of limited market uptake. To address these challenges, the implementation of adequate policies incentivizing the use of hydrogen vehicles and the reduction of the investment and operation costs of hydrogen refueling stations (HRS) are essential to put both investors and customers at ease. Even though the transition to hydrogen cars has been rather slow, public transportation companies have shown a keen interest in this highly promising fuel. Besides, their hydrogen demand is easier to predict and regulate than personal vehicles. Due to the reduced complexity of designing a suitable hydrogen supply chain for public vehicles, this sub-sector could be a great starting point to facilitate the adoption of hydrogen vehicles. Consequently, this study will focus on designing a chain of on-site green HRS for the public transportation network in Nantes Metropole leveraging the latest relevant technological advances aiming to reduce the costs while ensuring reliability, safety, and ease of access. To reduce the cost of HRS and encourage their widespread adoption, a network of 7 H35-T40 HRS has been designed, replacing the conventional J-T valves with turbo-expanders. Each station in the network has a daily capacity of 1,920 kg. Thus, the HRS network can produce up to 12.5 tH2 per day. The detailed cost analysis has revealed a CAPEX per station of 16.6 M euros leading to a network CAPEX of 116.2 M euros. The proposed station siting prioritized Nantes metropole’s 5 bus depots and included 2 city-centre locations. Thanks to the turbo-expander technology, the cooling capacity of the proposed HRS is 19% lower than that of a conventional station equipped with J-T valves, resulting in significant CAPEX savings estimated at 708,560 € per station, thus nearly 5 million euros for the whole HRS network. Besides, the turbo-expander power generation ranges from 7.7 to 112 kW. Thus, the power produced can be used within the station or sold as electricity to the main grid, which would, in turn, maximize the station’s profit. Despite the substantial initial investment required, the environmental benefits, cost savings, and energy efficiencies realized through the transition to hydrogen fuel cell buses and the deployment of HRS equipped with turbo-expanders offer considerable advantages for both TAN and Nantes Metropole. These initiatives underscore their enduring commitment to fostering green mobility and combatting climate change in the long term.

Keywords: green hydrogen, refueling stations, turbo-expander, heavy-duty vehicles

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