Search results for: growth and characterization
3081 Alternatives to the Disposal of Sludge from Water and Wastewater Treatment Plants
Authors: Lima Priscila, Gianotto Raiza, Arruda Leonan, Magalhães Filho Fernando
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Industrialization and especially the accentuated population growth in developing countries and the lack of drainage, public cleaning, water and sanitation services has caused concern about the need for expansion of water treatment units and sewage. However, these units have been generating by-products, such as the sludge. This paper aims to investigate aspects of operation and maintenance of sludge from a wastewater treatment plant (WWTP - 90 L.s-1) and two water treatment plants (WTPs; 1.4 m3.s-1 and 0.5 m3.s-1) for the purpose of proper disposal and reuse, evaluating their qualitative and quantitative characteristics, the Brazilian legislation and standards. It was concluded that the sludge from the water treatment plants is directly related to the quality of raw water collected, and it becomes feasible for use in construction materials, and to dispose it in the sewage system, improving the efficiency of the WWTP regarding precipitation of phosphorus (35% of removal). The WTP Lageado had 55,726 kg/month of sludge production, more than WTP Guariroba (29,336 kg/month), even though the flow of WTP Guariroba is 1,400 L.s-1 and the WTP Lagedo 500 L.s-1, being explained by the quality that influences more than the flow. The WWTP sludge have higher concentrations of organic materials due to their origin and could be used to improve the fertility of the soil, crop production and recovery of degraded areas. The volume of sludge generated at the WWTP was 1,760 ton/month, with 5.6% of solid content in the raw sludge and in the dewatered sludge it increased its content to 23%.Keywords: disposal, sludge, water treatment, wastewater treatment
Procedia PDF Downloads 3303080 An Investigation of the Structural and Microstructural Properties of Zn1-xCoxO Thin Films Applied as Gas Sensors
Authors: Ariadne C. Catto, Luis F. da Silva, Khalifa Aguir, Valmor Roberto Mastelaro
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Zinc oxide (ZnO) pure or doped are one of the most promising metal oxide semiconductors for gas sensing applications due to the well-known high surface-to-volume area and surface conductivity. It was shown that ZnO is an excellent gas-sensing material for different gases such as CO, O2, NO2 and ethanol. In this context, pure and doped ZnO exhibiting different morphologies and a high surface/volume ratio can be a good option regarding the limitations of the current commercial sensors. Different studies showed that the sensitivity of metal-doped ZnO (e.g. Co, Fe, Mn,) enhanced its gas sensing properties. Motivated by these considerations, the aim of this study consisted on the investigation of the role of Co ions on structural, morphological and the gas sensing properties of nanostructured ZnO samples. ZnO and Zn1-xCoxO (0 < x < 5 wt%) thin films were obtained via the polymeric precursor method. The sensitivity, selectivity, response time and long-term stability gas sensing properties were investigated when the sample was exposed to a different concentration range of ozone (O3) at different working temperatures. The gas sensing property was probed by electrical resistance measurements. The long and short-range order structure around Zn and Co atoms were investigated by X-ray diffraction and X-ray absorption spectroscopy. X-ray photoelectron spectroscopy measurement was performed in order to identify the elements present on the film surface as well as to determine the sample composition. Microstructural characteristics of the films were analyzed by a field-emission scanning electron microscope (FE-SEM). Zn1-xCoxO XRD patterns were indexed to the wurtzite ZnO structure and any second phase was observed even at a higher cobalt content. Co-K edge XANES spectra revealed the predominance of Co2+ ions. XPS characterization revealed that Co-doped ZnO samples possessed a higher percentage of oxygen vacancies than the ZnO samples, which also contributed to their excellent gas sensing performance. Gas sensor measurements pointed out that ZnO and Co-doped ZnO samples exhibit a good gas sensing performance concerning the reproducibility and a fast response time (around 10 s). Furthermore, the Co addition contributed to reduce the working temperature for ozone detection and improve the selective sensing properties.Keywords: cobalt-doped ZnO, nanostructured, ozone gas sensor, polymeric precursor method
Procedia PDF Downloads 2493079 Rethinking Nigeria's Foreign Policy in the Age of Global Terrorism
Authors: Shuaibu Umar Abdul
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This paper examines Nigeria’s foreign policy in the age of global terrorism. It worth saying that the threat of ‘terrorism’ is not peculiar to Western and Middle Eastern countries alone, its tentacles are now spreading all over, Africa inclusive. The issue of domestic terrorism in Nigeria has become pervasive since the return of democratic rule in 1999. This development has never been a witness in any form throughout the year of statehood in Nigeria, the issues of banditry, armed robbery, ritual killing, and criminal activities like kidnapping and pipeline vandalization, the breakdown of law and order, poorly managed infrastructural facilities and corruption remain synonymous to Nigeria. These acts of terrorism no doubt have constituted a challenge that necessitates the paradigm shift in Nigeria’s foreign policy. The study employed the conceptual framework of analysis to lead interrogation; secondary sources were used to generate data while descriptive and content analysis were considered for data presentation and interpretation. In view of the interrogation and discussion on the subject matter, the paper revealed that Nigerian government underrated and underestimated the strength of terrorism within and outside her policy hence, it becomes difficult to address. As a response to the findings and conclusion of the study, the paper recommends among others that Nigeria’s foreign policy has to be rethought, reshaped and remodeled in cognizance to the rising global terrorism for peace, growth and development in the country.Keywords: foreign policy, globe, Nigeria, rethinking, terrorism
Procedia PDF Downloads 3633078 Cardiolipin-Incorporated Liposomes Carrying Curcumin and Nerve Growth Factor to Rescue Neurons from Apoptosis for Alzheimer’s Disease Treatment
Authors: Yung-Chih Kuo, Che-Yu Lin, Jay-Shake Li, Yung-I Lou
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Curcumin (CRM) and nerve growth factor (NGF) were entrapped in liposomes (LIP) with cardiolipin (CL) to downregulate the phosphorylation of mitogen-activated protein kinases for Alzheimer’s disease (AD) management. AD belongs to neurodegenerative disorder with a gradual loss of memory, yielding irreversible dementia. CL-conjugated LIP loaded with CRM (CRM-CL/LIP) and that with NGF (NGF-CL/LIP) were applied to AD models of SK-N-MC cells and Wistar rats with an insult of β-amyloid peptide (Aβ). Lipids comprising 1,2-dipalmitoyl-sn-glycero-3- phosphocholine (Avanti Polar Lipids, Alabaster, AL), 1',3'-bis[1,2- dimyristoyl-sn-glycero-3-phospho]-sn-glycerol (CL; Avanti Polar Lipids), 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N- [methoxy(polyethylene glycol)-2000] (Avanti Polar Lipids), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[carboxy(polyethylene glycol)-2000] (Avanti Polar Lipids) and CRM (Sigma–Aldrich, St. Louis, MO) were dissolved in chloroform (J. T. Baker, Phillipsburg, NJ) and condensed using a rotary evaporator (Panchum, Kaohsiung, Taiwan). Human β-NGF (Alomone Lab, Jerusalem, Israel) was added in the aqueous phase. Wheat germ agglutinin (WGA; Medicago AB, Uppsala, Sweden) was grafted on LIP loaded with CRM for (WGA-CRM-LIP) and CL-conjugated LIP loaded with CRM (WGA-CRM-CL/LIP) using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (Sigma–Aldrich) and N-hydroxysuccinimide (Alfa Aesar, Ward Hill, MA). The protein samples of SK-N-MC cells (American Type Tissue Collection, Rockville, MD) were used for sodium dodecyl sulfate (Sigma–Aldrich) polyacrylamide gel (Sigma–Aldrich) electrophoresis. In animal study, the LIP formulations were administered by intravenous injection via a tail vein of male Wistar rats (250–280 g, 8 weeks, BioLasco, Taipei, Taiwan), which were housed in the Animal Laboratory of National Chung Cheng University in accordance with the institutional guidelines and the guidelines of Animal Protection Committee under the Council of Agriculture of the Republic of China. We found that CRM-CL/LIP could inhibit the expressions of phosphorylated p38 (p-p38), p-Jun N-terminal kinase (p-JNK), and p-tau protein at serine 202 (p-Ser202) to retard the neuronal apoptosis. Free CRM and released CRM from CRM-LIP and CRM-CL/LIP were not in a straightforward manner to effectively inhibit the expression of p-p38 and p-JNK in the cytoplasm. In addition, NGF-CL/LIP enhanced the quantities of p-neurotrophic tyrosine kinase receptor type 1 (p-TrkA) and p-extracellular-signal-regulated kinase 5 (p-ERK5), preventing the Aβ-induced degeneration of neurons. The membrane fusion of NGF-LIP activated the ERK5 pathway and the targeting capacity of NGF-CL/LIP enhanced the possibility of released NGF to affect the TrkA level. Moreover, WGA-CRM-LIP improved the permeation of CRM across the blood–brain barrier (BBB) and significantly reduced the Aβ plaque deposition and malondialdehyde level and increased the percentage of normal neurons and cholinergic function in the hippocampus of AD rats. This was mainly because the encapsulated CRM was protected by LIP against a rapid degradation in the blood. Furthermore, WGA on LIP could target N-acetylglucosamine on endothelia and increased the quantity of CRM transported across the BBB. In addition, WGA-CRM-CL/LIP could be effective in suppressing the synthesis of acetylcholinesterase and reduced the decomposition of acetylcholine for better neurotransmission. Based on the in vitro and in vivo evidences, WGA-CRM-CL/LIP can rescue neurons from apoptosis in the brain and can be a promising drug delivery system for clinical AD therapy.Keywords: Alzheimer’s disease, β-amyloid, liposome, mitogen-activated protein kinase
Procedia PDF Downloads 3333077 The Development and Survival of Solea aegyptiaca Raised on Artemia franciscana Supplemented with Four Distinct Microalgae Species Cultivated on Two Sources of Seawater
Authors: Hanan Mohamed Khairy
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This study used two water sources (Eastern Harbour (EH) and MaxWell (MW)) to assess suitable water sources to enhance Solea aegyptiaca aquaculture from the larval to the juvenile stage. Initially, the nutritional value of four microalgae (Chlorella salina, Tetraselmis chuii, Nannochloropsis salina, and N. oculata) was evaluated in the two water sources. When compared to EH, MW with a high nitrate level increased the algal biomass and the biochemical makeup of all species. Among the species under investigation, MW-N. salina had the highest growth and biochemical contents. It also produced Artemia franciscana, which had much higher levels of arachidonic acid (ARA), eicosapentaenoic acid (EPA ), and docosahexaenoic acid (DHA) than EH. Secondly, from 10–48 days post-hatch at a density of 15 larvae/L, Artemia-enriched MW-N salina was employed to improve S. aegyptiaca quality in both water sources. When compared to the strain raised on EH, the MW-S. aegyptiaca showed a noteworthy rise in morphometric parameters, albino percentages, and the greatest concentrations of ARA, EPA, and DHA (35.9, 6.1, and 15.9 µg/g, respectively). According to the study, MW-S. aegyptiaca albinism is caused by a high dietary and ARA content. From microalgae to S. aegyptiaca, the quality of the entire food chain is greatly influenced by the seawater supply.Keywords: albinism, Artemia franciscana, fatty acids, microalgae, seawater sources, Solea aegyptiaca
Procedia PDF Downloads 193076 Stability Analysis of Tumor-Immune Fractional Order Model
Authors: Sadia Arshad, Yifa Tang, Dumitru Baleanu
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A fractional order mathematical model is proposed that incorporate CD8+ cells, natural killer cells, cytokines and tumor cells. The tumor cells growth in the absence of an immune response is modeled by logistic law as it was the simplest form for which predictions also agreed with the experimental data. Natural Killer Cells are our first line of defense. NK cells directly kill tumor cells through several mechanisms, including the release of cytoplasmic granules containing perforin and granzyme, expression of tumor necrosis factor (TNF) family members. The effect of the NK cells on the tumor cell population is expressed with the product term. Rational form is used to describe interaction between CD8+ cells and tumor cells. A number of cytokines are produced by NKs, including tumor necrosis factor TNF, IFN, and interleukin (IL-10). Source term for cytokines is modeled by Michaelis-Menten form to indicate the saturated effects of the immune response. Stability of the equilibrium points is discussed for biologically significant values of bifurcation parameters. We studied the treatment of fractional order system by investigating analytical conditions of tumor eradication. Numerical simulations are presented to illustrate the analytical results.Keywords: cancer model, fractional calculus, numerical simulations, stability analysis
Procedia PDF Downloads 3183075 Rathke’s Cleft Cyst Presenting as Unilateral Visual Field Defect
Authors: Ritesh Verma, Manisha Rathi, Chand Singh Dhull, Sumit Sachdeva, Jitender Phogat
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A Rathke's cleft cyst is a benign growth found on the pituitary gland in the brain, specifically a fluid-filled cyst in the posterior portion of the anterior pituitary gland. It occurs when the Rathke's pouch does not develop properly and ranges in size from 2 to 40mm in diameter. A 38-year-old male presented to the outpatient department with loss of vision in the inferior quadrant of the left eye since 15 days. Visual acuity was 6/6 in the right eye and 6/9 in the left eye. Visual field analysis by HFA-24-2 revealed an inferior field defect extending to the supero-temporal quadrant in the left eye. MRI brain and orbit was advised to the patient and it revealed a well defined cystic pituitary adenoma indenting left optic nerve near optic chiasm consistent with the diagnosis of Rathke’s cleft cyst (RCC). The patient was referred to neurosurgery department for further management. Symptoms vary greatly between individuals having RCCs. RCCs can be non-functioning, functioning, or both. Besides headaches, neurocognitive deficits are almost always present but have a high rate of immediate reversal if the cyst is properly treated or drained.Keywords: pituitary tumors, rathke’s cleft cyst, visual field defects, vision loss
Procedia PDF Downloads 2093074 Excitation Density and Energy Dependent Relaxation Dynamics of Charge Carriers in Large Area 2D TMDCs
Authors: Ashish Soni, Suman Kalyan Pal
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Transition metal dichalcogenides (TMDCs) are an emerging paradigm for the generation of advanced materials which are capable of utilizing in future device applications. In recent years TMDCs have attracted researchers for their unique band structure in monolayers. Large-area monolayers could become the most appropriate candidate for flexible and thin optoelectronic devices. For this purpose, it is crucial to understand the generation and transport of charge carriers in low dimensions. A deep understanding of photo-generated hot charges and trapped charges is essential to improve the performance of optoelectronic devices. Carrier trapping by the defect states that are introduced during the growth process of the monolayer could influence the dynamical behaviour of charge carriers. Herein, we investigated some aspects of the ultrafast evolution of the initially generated hot carriers and trapped charges in large-area monolayer WS₂ by measuring transient absorption at energies above and below the band gap energy. Our excitation density and energy-dependent measurements reveal the trapping of the initially generated charge carrier. Our results could be beneficial for the development of TMDC-based optoelectronic devices.Keywords: transient absorption, optoelectronics, 2D materials, TMDCs, exciton
Procedia PDF Downloads 723073 Case Report: Clinical Improvement of Forbrain Neurologic Signs in 3- Month- Old Persian Mastiff Dog with Calvarial Hyperostosis Syndrome after Corticosteroid, Antiepileptic and Antibiotic Therapy
Authors: Hamidreza Jahani, Zahra Salehzadeh, Ehsan Amini, Mohsen Tohidifar
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Calvarial Hyperostosis Syndrome (CHS) is a benign bone disease of the skull. It is a non-neoplastic and proliferative bone disease, and the main feature of the disease is progressive and asymmetrical bone involvement. CHS is mostly reported in young male and female bullmastiff dogs and less frequently in other breeds. The etiology of CHS is unknown. This is the first case report of CHS in Iran. A 3-month-old male Persian Mastiff was presented with chief complaints of multiple episodes of seizure, pacing, bizarre behavior, delayed growth, head pressing, and difficulty in opening the mouth. Central blindness and open fontanelles were observed in clinical examination. No abnormality was found in the complete blood count and routine blood biochemical tests. CT scan findings include cortical thickening of frontal and parietal bones and enlargement of the left retropharyngeal lymph node. For treatment, oral clindamycin for two weeks, prednisolone and phenobarbital for one month, respectively, were administrated, and the case showed improvement after a week and recovered after one month.Keywords: calvarial hyperostosis, Persian Mastiff, frontal bone, seizure
Procedia PDF Downloads 1423072 Obtainment of Systems with Efavirenz and Lamellar Double Hydroxide as an Alternative for Solubility Improvement of the Drug
Authors: Danilo A. F. Fontes, Magaly A. M.Lyra, Maria L. C. Moura, Leslie R. M. Ferraz, Salvana P. M. Costa, Amanda C. Q. M. Vieira, Larissa A. Rolim, Giovanna C. R. M. Schver, Ping I. Lee, Severino Alves-Júnior, José L. Soares-Sobrinho, Pedro J. Rolim-Neto
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Efavirenz (EFV) is a first-choice drug in antiretroviral therapy with high efficacy in the treatment of infection by Human Immunodeficiency Virus, which causes Acquired Immune Deficiency Syndrome (AIDS). EFV has low solubility in water resulting in a decrease in the dissolution rate and, consequently, in its bioavailability. Among the technological alternatives to increase solubility, the Lamellar Double Hydroxides (LDH) have been applied in the development of systems with poorly water-soluble drugs. The use of analytical techniques such as X-Ray Diffraction (XRD), Infrared Spectroscopy (IR) and Differential Scanning Calorimetry (DSC) allowed the elucidation of drug interaction with the lamellar compounds. The objective of this work was to characterize and develop the binary systems with EFV and LDH in order to increase the solubility of the drug. The LDH-CaAl was synthesized by the method of co-precipitation from salt solutions of calcium nitrate and aluminum nitrate in basic medium. The systems EFV-LDH and their physical mixtures (PM) were obtained at different concentrations (5-60% of EFV) using the solvent technique described by Takahashi & Yamaguchi (1991). The characterization of the systems and the PM’s was performed by XRD techniques, IR, DSC and dissolution test under non-sink conditions. The results showed improvements in the solubility of EFV when associated with LDH, due to a possible change in its crystal structure and formation of an amorphous material. From the DSC results, one could see that the endothermic peak at 173°C, temperature that correspond to the melting process of EFZ in the crystal form, was present in the PM results. For the EFZ-LDH systems (with 5, 10 and 30% of drug loading), this peak was not observed. XRD profiles of the PM showed well-defined peaks for EFV. Analyzing the XRD patterns of the systems, it was found that the XRD profiles of all the systems showed complete attenuation of the characteristic peaks of the crystalline form of EFZ. The IR technique showed that, in the results of the PM, there was the appearance of one band and overlap of other bands, while the IR results of the systems with 5, 10 and 30% drug loading showed the disappearance of bands and a few others with reduced intensity. The dissolution test under non-sink conditions showed that systems with 5, 10 and 30% drug loading promoted a great increase in the solubility of EFV, but the system with 10% of drug loading was the only one that could keep substantial amount of drug in solution at different pHs.Keywords: Efavirenz, Lamellar Double Hydroxides, Pharmaceutical Techonology, Solubility
Procedia PDF Downloads 5903071 Exploitation of Variability for Salinity Tolerance in Maize Hybrids (Zea Mays L.) at Early Growth Stage
Authors: Abdul Qayyum, Hafiz Muhammad Saeed, Mamoona Hanif, Etrat Noor, Waqas Malik, Shoaib Liaqat
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Salinity is extremely serious problem that has a drastic effect on maize crop, environment and causes economic losses of country. An advance technique to overcome salinity is to develop salt tolerant geno types which require screening of huge germplasm to start a breeding program. Therefore, present study was undertaken to screen out 25 maize hybrids of different origin for salinity tolerance at seedling stage under three levels of salt stress 250 and 300 mM NaCl including one control. The existence of variation for tolerance to enhanced NaCl salinity levels at seedling stage in maize proved that hybrids had differing ability to grow under saline environment and potential variability within specie. Almost all the twenty five maize hybrids behaved varyingly in response to different salinity levels. However, the maize hybrids H6, H13, H21, H23 and H24 expressed better performance under salt stress in terms of all six characters and proved to be as highly tolerant while H22, H17 H20, H18, H4, H9, and H8 were identified as moderately tolerant. Hybrids H14, H5, H11 and H3 H12, H2, were expressed as most sensitive to salinity suggesting that screening is an effective tool to exploit genetic variation among maize hybrids and salt tolerance in maize can be enhanced through selection and breeding procedure.Keywords: salinity, hybrids, maize, variation
Procedia PDF Downloads 7203070 Synthesis and Characterization of AFe₂O₄ (A=CA, Co, CU) Nano-Spinels: Application to Hydrogen Photochemical Production under Visible Light Irradiation
Authors: H. Medjadji, A. Boulahouache, N. Salhi, A. Boudjemaa, M. Trari
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Hydrogen from renewable sources, such as solar, is referred to as green hydrogen. The splitting water process using semiconductors, such as photocatalysts, has attracted significant attention due to its potential application for solving the energy crisis and environmental pollution. Spinel ferrites of the MF₂O₄ type have shown broad interest in diverse energy conversion processes, including fuel cells and photo electrocatalytic water splitting. This work focuses on preparing nano-spinels based on iron AFe₂O₄ (A= Ca, Co, and Cu) as photocatalysts using the nitrate method. These materials were characterized both physically and optically and subsequently tested for hydrogen generation under visible light irradiation. Various techniques were used to investigate the properties of the materials, including TGA-DT, X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), UV-visible spectroscopy, Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDX) and X-ray Photoelectron Spectroscopy (XPS) was also undertaken. XRD analysis confirmed the formation of pure phases at 850°C, with crystalline sizes of 31 nm for CaFe₂O₄, 27 nm for CoFe₂O₄, and 40 nm for CuFe₂O₄. The energy gaps, calculated from recorded diffuse reflection data, are 1.85 eV for CaFe₂O₄, 1.27 eV for CoFe₂O₄, and 1.64 eV for CuFe₂O₄. SEM micrographs showed homogeneous grains with uniform shapes and medium porosity in all samples. EDX elemental analysis determined the absence of any contaminating elements, highlighting the high purity of the prepared materials via the nitrate route. XPS spectra revealed the presence of Fe3+ and O in all samples. Additionally, XPS analysis revealed the presence of Ca²⁺, Co²⁺, and Cu²⁺ on the surface of CaFe₂O₄ and CoFe₂O₄ spinels, respectively. The photocatalytic activity was successfully evaluated by measuring H₂ evolution through the water-splitting process. The best performance was achieved with CaFe₂O₄ in a neutral medium (pH ~ 7), yielding 189 µmol at an optimal temperature of ~50°C. The highest hydrogen production rates for CoFe₂O₄ and CuFe₂O₄ were obtained at pH ~ 12 with release rates of 65 and 85 µmol, respectively, under visible light irradiation at the same optimal temperature. Various conditions were investigated including the pH of the solution, the hole sensors utilization and recyclability.Keywords: hydrogen, MFe₂O₄, nitrate route, spinel ferrite
Procedia PDF Downloads 443069 Fuel Quality of Biodiesel from Chlorella protothecoides Microalgae Species
Authors: Mukesh Kumar, Mahendra Pal Sharma
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Depleting fossil fuel resources coupled with serious environmental degradation has led to the search for alternative resources for biodiesel production as a substitute of Petro-diesel. Currently, edible, non-edible oils and microalgal plant species are cultivated for biodiesel production. Looking at the demerits of edible and non-edible oil resources, the focus is being given to grow microalgal species having high oil productivities, less maturity time and less land requirement. Out of various microalgal species, Chlorella protothecoides is considered as the most promising species for biodiesel production owing to high oil content (58 %), faster growth rate (24–48 h) and high biomass productivity (1214 mg/l/day). The present paper reports the results of optimization of reaction parameters of transesterification process as well as the kinetics of transesterification with 97% yield of biodiesel. The measurement of fuel quality of microalgal biodiesel shows that the biodiesel exhibit very good oxidation stability (O.S) of 7 hrs, more than ASTM D6751 (3 hrs) and EN 14112 (6 hrs) specifications. The CP and PP of 0 and -3 °C are finding as per ASTM D 2500-11 and ASTM D 97-12 standards. These results show that the microalgal biodiesel does not need any enhancement in O.S & CFP and hence can be recommended to be directly used as MB100 or its blends into diesel engine operation. Further, scope is available for the production of binary blends using poor quality biodiesel for engine operation.Keywords: fuel quality, methyl ester yield, microalgae, transesterification
Procedia PDF Downloads 2193068 Characterization of the Blood Microbiome in Rheumatoid Arthritis Patients Compared to Healthy Control Subjects Using V4 Region 16S rRNA Sequencing
Authors: D. Hammad, D. P. Tonge
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Rheumatoid arthritis (RA) is a disabling and common autoimmune disease during which the body's immune system attacks healthy tissues. This results in complicated and long-lasting actions being carried out by the immune system, which typically only occurs when the immune system encounters a foreign object. In the case of RA, the disease affects millions of people and causes joint inflammation, ultimately leading to the destruction of cartilage and bone. Interestingly, the disease mechanism still remains unclear. It is likely that RA occurs as a result of a complex interplay of genetic and environmental factors including an imbalance in the microorganism population inside our body. The human microbiome or microbiota is an extensive community of microorganisms in and on the bodies of animals, which comprises bacteria, fungi, viruses, and protozoa. Recently, the development of molecular techniques to characterize entire bacterial communities has renewed interest in the involvement of the microbiome in the development and progression of RA. We believe that an imbalance in some of the specific bacterial species in the gut, mouth and other sites may lead to atopobiosis; the translocation of these organisms into the blood, and that this may lead to changes in immune system status. The aim of this study was, therefore, to characterize the microbiome of RA serum samples in comparison to healthy control subjects using 16S rRNA gene amplification and sequencing. Serum samples were obtained from healthy control volunteers and from patients with RA both prior to, and following treatment. The bacterial community present in each sample was identified utilizing V4 region 16S rRNA amplification and sequencing. Bacterial identification, to the lowest taxonomic rank, was performed using a range of bioinformatics tools. Significantly, the proportions of the Lachnospiraceae, Ruminococcaceae, and Halmonadaceae families were significantly increased in the serum of RA patients compared with healthy control serum. Furthermore, the abundance of Bacteroides and Lachnospiraceae nk4a136_group, Lachnospiraceae_UGC-001, RuminococcaceaeUCG-014, Rumnococcus-1, and Shewanella was also raised in the serum of RA patients relative to healthy control serum. These data support the notion of a blood microbiome and reveal RA-associated changes that may have significant implications for biomarker development and may present much-needed opportunities for novel therapeutic development.Keywords: blood microbiome, gut and oral bacteria, Rheumatoid arthritis, 16S rRNA gene sequencing
Procedia PDF Downloads 1363067 Synthesis and Characterization of LiCoO2 Cathode Material by Sol-Gel Method
Authors: Nur Azilina Abdul Aziz, Tuti Katrina Abdullah, Ahmad Azmin Mohamad
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Lithium-transition metals and some of their oxides, such as LiCoO2, LiMn2O2, LiFePO4, and LiNiO2 have been used as cathode materials in high performance lithium-ion rechargeable batteries. Among the cathode materials, LiCoO2 has potential to been widely used as a lithium-ion battery because of its layered crystalline structure, good capacity, high cell voltage, high specific energy density, high power rate, low self-discharge, and excellent cycle life. This cathode material has been widely used in commercial lithium-ion batteries due to its low irreversible capacity loss and good cycling performance. However, there are several problems that interfere with the production of material that has good electrochemical properties, including the crystallinity, the average particle size and particle size distribution. In recent years, synthesis of nanoparticles has been intensively investigated. Powders prepared by the traditional solid-state reaction have a large particle size and broad size distribution. On the other hand, solution method can reduce the particle size to nanometer range and control the particle size distribution. In this study, LiCoO2 was synthesized using the sol–gel preparation method, which Lithium acetate and Cobalt acetate were used as reactants. The stoichiometric amounts of the reactants were dissolved in deionized water. The solutions were stirred for 30 hours using magnetic stirrer, followed by heating at 80°C under vigorous stirring until a viscous gel was formed. The as-formed gel was calcined at 700°C for 7 h under a room atmosphere. The structural and morphological analysis of LiCoO2 was characterized using X-ray diffraction and Scanning electron microscopy. The diffraction pattern of material can be indexed based on the α-NaFeO2 structure. The clear splitting of the hexagonal doublet of (006)/(102) and (108)/(110) in this patterns indicates materials are formed in a well-ordered hexagonal structure. No impurity phase can be seen in this range probably due to the homogeneous mixing of the cations in the precursor. Furthermore, SEM micrograph of the LiCoO2 shows the particle size distribution is almost uniform while particle size is between 0.3-0.5 microns. In conclusion, LiCoO2 powder was successfully synthesized using the sol–gel method. LiCoO2 showed a hexagonal crystal structure. The sample has been prepared clearly indicate the pure phase of LiCoO2. Meanwhile, the morphology of the sample showed that the particle size and size distribution of particles is almost uniform.Keywords: cathode material, LiCoO2, lithium-ion rechargeable batteries, Sol-Gel method
Procedia PDF Downloads 3773066 Hsa-miR-326 Functions as a Tumor Suppressor in Non-Small Cell Lung Cancer through Targeting CCND1
Authors: Cheng-Cao Sun, Shu-Jun Li, Cuili Yang, Yongyong Xi, Liang Wang, Feng Zhang, De-Jia Li
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Hsa-miRNA-326 (miR-326) has recently been discovered having anticancer efficacy in different organs. However, the role of miR-326 on non-small cell lung cancer (NSCLC) is still ambiguous. In this study, we investigated the role of miR-326 on the development of NSCLC. The results indicated that miR-326 was significantly down-regulated in primary tumor tissues and very low levels were found in NSCLC cell lines. Ectopic expression of miR-326 in NSCLC cell lines significantly suppressed cell growth as evidenced by cell viability assay, colony formation assay and BrdU staining, through inhibition of cyclin D1, cyclin D2, CDK4, and up-regulation of p57(Kip2) and p21(Waf1/Cip1). In addition, miR-326 induced apoptosis, as indicated by concomitantly with up-regulation of key apoptosis protein cleaved caspase-3, and down-regulation of anti-apoptosis protein Bcl2. Moreover, miR-326 inhibited cellular migration and invasiveness through inhibition of matrix metalloproteinases (MMP)-7 and MMP-9. Further, oncogene CCND1 was revealed to be a putative target of miR-326, which was inversely correlated with miR-326 expression in NSCLC. Taken together, our results demonstrated that miR-326 played a pivotal role on NSCLC through inhibiting cell proliferation, migration, invasion, and promoting apoptosis by targeting oncogenic CCND1.Keywords: hsa-miRNA-326 (miR-326), cyclin D1, non-small cell lung cancer (NSCLC), proliferation, apoptosis
Procedia PDF Downloads 3083065 Evaluation of Collagen Synthesis in Macrophages/Fibroblasts Co-Culture Using Polylactic Acid Particles as Stimulants
Authors: Feng Ju Chuang, Yu Wen Wang, Tai Jung Hsieh, Shyh Ming Kuo
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Polylactic acid is a synthetic polymer with good biocompatibility and degradability, is widely used in clinical applications. In this study, we utilized Polylactic acid particles as stimulants for macrophages and the collagen synthesis of co-cultured fibroblasts was evaluated. The results indicated that Polylactic acid particles were nontoxic to cells from 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. No obvious inflammation effect was observed (under the PLLA concentration of 1 mg/mL) after 24-h co-culture of Raw264.7 and NIH3T3 cells (from TNF-α assay). The addition of PLLA particles to the Raw264.7 and NIH3T3 co-cultures increased the synthesis of collagen, the highest collagen synthesis from the fibroblast was the 0.2 mg/mL (approximately 60% increased as compared with without addition Polylactic acid particles). Moreover, a co-axial atomization delivery device was used to percutaneously introduce Polylactic acid particles into the dermis layer and stimulating macrophages to secrete growth factors promoting fibroblasts to produce collagen. The preliminary results demonstrated the synthesis of collagen was increased mildly after the introduction of Polylactic acid particles for 28-d post implantation. The Polylactic acid particles could be successfully introduced into the dermis layer from H&E staining examination, however, the optimum concentration of Polylactic acid particles and the time-period for collagen synthesis still need to be evaluated.Keywords: collagen synthesis, macrophage, NIH3T3 cells, polylactic acid particles
Procedia PDF Downloads 1183064 Microbial Diversity of El-Baida Marsh: Setif, Algeria
Authors: H. Necef, A. Benayad
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Fungi are becoming more and more important in our life. Therefore, as a start for the symposium on filamentous fungi in biotechnology a short survey of the role of fungi in biotechnology. Salin soils occupy about 7% of land area; they are characterized by unsuitable physical conditions for the growth of living organisms. However, researches showed that some microorganisms especially fungi are able to grow and adapt to such extreme conditions; it is due to their ability to develop different physiological mechanisms in their adaptation. This is the first study on the physiological and biological characteristics of El-Beida marsh. Nine soil samples were taken at different points in two steps, the first was in winter (low temperature), and the second was in summer (high temperature). The physicochemical analyses of the soil were conducted, then the isolation process was applied using two methods, direct method and dilution method (10-1, 10-2, 10-3, 10-4). Different species of fungi were identified belong to 21 genera in addition to 3 yeast species, Aspergillus showed the highest proportion by 43%, then Penicillium by 20% then Alternaria by 7%, in addition to various genera in different proportions. As for the sampling periods, it was observed that the spread of fungi in winter was higher than in summer with the proportion 75.47% and 24.53% respectively. Some halotolerant fungi have a biotechnological importance especially if the salinity of the medium is necessary for the fermentation, and if the halotolerance genes of the fungus will define, this will open the research to study and improve this property for the industrial important micro-organisms.Keywords: salinity, identification, aspergillus oryzae, halotolerance, fungi
Procedia PDF Downloads 4063063 The Role of Substrate-Nozzle Distance in Atomic Nebulizers in the Photoelectrochemical Water Splitting Performance of ZnO Nanorods
Authors: Lukman Andi Priyatna, Vivi Fauzia, Ferry Anggoro Ardy Nugroho
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Zinc oxide (ZnO) based nanostructures are ubiquitous in applications due to their favourable physicochemical properties and ease of fabrication. One widely accessible route to synthesize ZnO nanorods, which show promising performance in e.g. photoelectrochemical water splitting, is hydrothermal growth of ZnO seeds, obtained via an atomic nebulizer. Despite its popularity, study on the impact of the synthesis parameters in atomic nebulizer on the performance of the synthesized ZnO nanostructures is lacking. This study presents an investigation on the impact of the distance between substrates and atomic nebulizer nozzle on the photoelectrochemical water splitting performance of ZnO nanorods. Adjusting such a distance reveals an optimum separation which results in nanostructures with highest absorbance. Such high absorbance translates into improved photoelectrochemistry, as evaluated by higher photocurrent density, from 0.11 mA/cm² to 0.14 mA/cm² and higher Applied Bias Photon-to-Current Efficiency (ABPE) from 0.12% to 0.14%. These results underscore the importance of understanding and optimizing the experimental parameters during ZnO nanostructure synthesis. In a broader context, it advertises the need to carefully assess the corresponding fabrication parameters to optimize the performance of the obtained nanostructures.Keywords: atomic nebulizer, photocurrent density, photoelectrochemical water splitting, ZnO nanorods
Procedia PDF Downloads 373062 Industrial Policy Directions in Georgia
Authors: Nino Grigolaia
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Introduction - The paper discusses the role of industrial policy in the development of the economy in the country. The main challenges on the way to the implementation of industrial policy are analyzed: the long-term period of industrial policy, the risk of changes in priorities, the limited scope and external shocks. Methodology - Various research methods are used in the paper. The methods of induction, deduction, analysis, synthesis, analogy, correlation and statistical observation are used. Main Findings - Based on the analysis of the current situation in Georgia, the obstacles to the country's industrialization and its supporting factors are identified. Also, the challenges of the country's core industrial policies are revealed. Specific industry development strategies, ways of state support and main directions of new industrial policies are identified. Conclusion - The paper concludes that the development of the industrial sector is critical for the future growth and development of the Georgian economy, which will accelerate the industrialization and structural transformation processes, reduce the trade deficit, increase the exports and create more jobs in the country. The listed changes will guarantee the improvement of the socio-economic situation of the population. Accordingly, it is revealed that the study of industrial policy in Georgia is still actual. Based on the analysis, relevant conclusions in the field of industrialization of the country are developed and recommendations are proposed.Keywords: industrialization , industrial policy, industrialization of the economy, Georgia priorities
Procedia PDF Downloads 1943061 Desalination via Electrodialysis: A Newly Designed Fixed Bed Reactor Powered by Renewable Energy Source
Authors: Hend Mesbah, Yehia Youssef, Ibrahim Hassan, Shaaban Nosier, Ahmed El-Shazly, Ahmed Helal
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The problem of drinking water shortage is becoming more crucial nowadays as a result of the increased demand due to the population growth and the rise in the standard living. In recent years, desalination using electrodialysis powered by solar energy (PV-ED) is being widely used to help provide treated water and reduce the scarcity in water supply. In the present study, a water desalination laboratory scale ED cell with a fixed bed circulation system was designed, developed, and tested. The effect of three parameters (namely, cell voltage , flowrate, and salt concentration) on the removal percentage of salt ions was studied. The cell voltage was adjusted at 3 , 4 and 6 V. A flow rate of 5, 10, and 20 ml/s and an initial salt concentration of 2000, 5000, and 7000 ppm were investigated. The maximum salt percentage removal obtained was 52.5% at the lowest initial concentration (2000 ppm) and at the highest cell voltage (6 V). There was no significant effect of the flow rate on the removal percentage. A model of PV module has also been developed to calculate the dimensions of a solar cell based on the amount of energy consumed and it was calculated from the Overall ED cell voltage.Keywords: desalination, electrodialysis, solar desalination, photovoltaic electrodialysis
Procedia PDF Downloads 1513060 Optimization of Lubricant Distribution with Alternative Coordinates and Number of Warehouses Considering Truck Capacity and Time Windows
Authors: Taufik Rizkiandi, Teuku Yuri M. Zagloel, Andri Dwi Setiawan
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Distribution and growth in the transportation and warehousing business sector decreased by 15,04%. There was a decrease in Gross Domestic Product (GDP) contribution level from rank 7 of 4,41% in 2019 to 3,81% in rank 8 in 2020. A decline in the transportation and warehousing business sector contributes to GDP, resulting in oil and gas companies implementing an efficient supply chain strategy to ensure the availability of goods, especially lubricants. Fluctuating demand for lubricants and warehouse service time limits are essential things that are taken into account in determining an efficient route. Add depots points as a solution so that demand for lubricants is fulfilled (not stock out). However, adding a depot will increase operating costs and storage costs. Therefore, it is necessary to optimize the addition of depots using the Capacitated Vehicle Routing Problem with Time Windows (CVRPTW). This research case study was conducted at an oil and gas company that produces lubricants from 2019 to 2021. The study results obtained the optimal route and the addition of a depot with a minimum additional cost. The total cost remains efficient with the addition of a depot when compared to one depot from Jakarta.Keywords: CVRPTW, optimal route, depot, tabu search algorithm
Procedia PDF Downloads 1413059 A Comparative Study of Sampling-Based Uncertainty Propagation with First Order Error Analysis and Percentile-Based Optimization
Authors: M. Gulam Kibria, Shourav Ahmed, Kais Zaman
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In system analysis, the information on the uncertain input variables cause uncertainty in the system responses. Different probabilistic approaches for uncertainty representation and propagation in such cases exist in the literature. Different uncertainty representation approaches result in different outputs. Some of the approaches might result in a better estimation of system response than the other approaches. The NASA Langley Multidisciplinary Uncertainty Quantification Challenge (MUQC) has posed challenges about uncertainty quantification. Subproblem A, the uncertainty characterization subproblem, of the challenge posed is addressed in this study. In this subproblem, the challenge is to gather knowledge about unknown model inputs which have inherent aleatory and epistemic uncertainties in them with responses (output) of the given computational model. We use two different methodologies to approach the problem. In the first methodology we use sampling-based uncertainty propagation with first order error analysis. In the other approach we place emphasis on the use of Percentile-Based Optimization (PBO). The NASA Langley MUQC’s subproblem A is developed in such a way that both aleatory and epistemic uncertainties need to be managed. The challenge problem classifies each uncertain parameter as belonging to one the following three types: (i) An aleatory uncertainty modeled as a random variable. It has a fixed functional form and known coefficients. This uncertainty cannot be reduced. (ii) An epistemic uncertainty modeled as a fixed but poorly known physical quantity that lies within a given interval. This uncertainty is reducible. (iii) A parameter might be aleatory but sufficient data might not be available to adequately model it as a single random variable. For example, the parameters of a normal variable, e.g., the mean and standard deviation, might not be precisely known but could be assumed to lie within some intervals. It results in a distributional p-box having the physical parameter with an aleatory uncertainty, but the parameters prescribing its mathematical model are subjected to epistemic uncertainties. Each of the parameters of the random variable is an unknown element of a known interval. This uncertainty is reducible. From the study, it is observed that due to practical limitations or computational expense, the sampling is not exhaustive in sampling-based methodology. That is why the sampling-based methodology has high probability of underestimating the output bounds. Therefore, an optimization-based strategy to convert uncertainty described by interval data into a probabilistic framework is necessary. This is achieved in this study by using PBO.Keywords: aleatory uncertainty, epistemic uncertainty, first order error analysis, uncertainty quantification, percentile-based optimization
Procedia PDF Downloads 2453058 Social Enterprises over Microfinance Institutions: The Challenges of Governance and Management
Authors: Dean Sinković, Tea Golja, Morena Paulišić
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Upon the end of the vicious war in former Yugoslavia in 1995, international development community widely promoted microfinance as the key development framework to eradicate poverty, create jobs, increase income. Widespread claims were made that microfinance institutions would play vital role in creating a bedrock for sustainable ‘bottom-up’ economic development trajectory, thus, helping newly formed states to find proper way from economic post-war depression. This uplifting neoliberal narrative has no empirical support in the Republic of Croatia. Firstly, the type of enterprises created via microfinance sector are small, unskilled, labor intensive, no technology and with huge debt burden. This results in extremely high failure rates of microenterprises and poor individuals plunging into even deeper poverty, acute indebtedness and social marginalization. Secondly, evidence shows that microcredit is exact reflection of dangerous and destructive sub-prime lending model with ‘boom-to-bust’ scenarios in which benefits are solely extracted by the tiny financial and political elite working around the microfinance sector. We argue that microcredit providers are not proper financial structures through which developing countries should look way out of underdevelopment and poverty. In order to achieve sustainable long-term growth goals, public policy needs to focus on creating, supporting and facilitating the small and mid-size enterprises development. These enterprises should be technically sophisticated, capable of creating new capabilities and innovations, with managerial expertise (skills formation) and inter-connected with other organizations (i.e. clusters, networks, supply chains, etc.). Evidence from South-East Europe suggest that such structures are not created via microfinance model but can be fostered through various forms of social enterprises. Various legal entities may operate as social enterprises: limited liability private company, limited liability public company, cooperative, associations, foundations, institutions, Mutual Insurances and Credit union. Our main hypothesis is that cooperatives are potential agents of social and economic transformation and community development in the region. Financial cooperatives are structures that can foster more efficient allocation of financial resources involving deeper democratic arrangements and more socially just outcomes. In Croatia, pioneers of the first social enterprises were civil society organizations whilst forming a separated legal entity. (i.e. cooperatives, associations, commercial companies working on the principles of returning the investment to the founder). Ever since 1995 cooperatives in Croatia have not grown by pursuing their own internal growth but mostly by relying on external financial support. The greater part of today’s registered cooperatives tend to be agricultural (39%), followed by war veterans cooperatives (38%) and others. There are no financial cooperatives in Croatia. Due to the above mentioned we look at the historical developments and the prevailing social enterprises forms and discuss their advantages and disadvantages as potential agents for social and economic transformation and community development in the region. There is an evident lack of understanding of this business model and of its potential for social and economic development followed by an unfavorable institutional environment. Thus, we discuss the role of governance and management in the formation of social enterprises in Croatia, stressing the challenges for the governance of the country’s social enterprise movement.Keywords: financial cooperatives, governance and management models, microfinance institutions, social enterprises
Procedia PDF Downloads 2803057 Degree of Bending in Axially Loaded Tubular KT-Joints of Offshore Structures: Parametric Study and Formulation
Authors: Hamid Ahmadi, Shadi Asoodeh
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The fatigue life of tubular joints commonly found in offshore industry is not only dependent on the value of hot-spot stress (HSS), but is also significantly influenced by the through-the-thickness stress distribution characterized by the degree of bending (DoB). The determination of DoB values in a tubular joint is essential for improving the accuracy of fatigue life estimation using the stress-life (S–N) method and particularly for predicting the fatigue crack growth based on the fracture mechanics (FM) approach. In the present paper, data extracted from finite element (FE) analyses of tubular KT-joints, verified against experimental data and parametric equations, was used to investigate the effects of geometrical parameters on DoB values at the crown 0˚, saddle, and crown 180˚ positions along the weld toe of central brace in tubular KT-joints subjected to axial loading. Parametric study was followed by a set of nonlinear regression analyses to derive DoB parametric formulas for the fatigue analysis of KT-joints under axial loads. The tubular KT-joint is a quite common joint type found in steel offshore structures. However, despite the crucial role of the DoB in evaluating the fatigue performance of tubular joints, this paper is the first attempt to study and formulate the DoB values in KT-joints.Keywords: tubular KT-joint, fatigue, degree of bending (DoB), axial loading, parametric formula
Procedia PDF Downloads 3653056 Comparison between Effects of Free Curcumin and Curcumin Loaded NIPAAm-MAA Nanoparticles on Telomerase and Pinx1 Gene Expression in Lung Cancer Cells
Authors: Y. Pilehvar-Soltanahmadi, F. Badrzadeh, N. Zarghami, S. Jalilzadeh-Tabrizi, R. Zamani
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Herbal compounds such as curcumin which decrease telomerase and gene expression have been considered as beneficial tools for lung cancer treatment. In this article, we compared the effects of pure curcumin and curcumin-loaded NIPAAm-MAA nanoparticles on telomerase and PinX1 gene expression in a lung cancer cell line. A tetrazolium-based assay was used for determination of cytotoxic effects of curcumin on the Calu-6 lung cancer cell line and telomerase and pinX1 gene expression was measured with real-time PCR. MTT assay showed that Curcumin-loaded NIPAAm-MAA inhibited the growth of the Calu-6 lung cancer cell line in a time and dose-dependent manner. Our q-PCR results showed that the expression of telomerase gene was effectively reduced as the concentration of curcumin-loaded NIPAAm-MAA increased while expression of the PinX1 gene became elevated. The results showed that curcumin loaded NIPAAm-MAA exerted cytotoxic effects on the Calu-6 cell line through down-regulation of telomerase and stimulation of pinX1 gene expression. NIPPAm-MAA could be the good carrier for such kinds of hydrophobic agent.Keywords: curcumin, NIPAAm-MAA, PinX1, telomerase, lung cancer cells
Procedia PDF Downloads 3053055 Effect of Cuminum Cyminum L. Essential Oil on Staphylococcus Aureus during the Manufacture, Ripening and Storage of White Brined Cheese
Authors: Ali Misaghi, Afshin Akhondzadeh Basti, Ehsan Sadeghi
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Staphylococcus aureus is a pathogen of major concern for clinical infection and food borne illness. Humans and most domesticated animals harbor S. aureus, and so we may expect staphylococci to be present in food products of animal origin or in those handled directly by humans, unless heat processing is applied to destroy them. Cuminum cyminum L. has been allocated the topic of some recent studies in addition to its well-documented traditional usage for treatment of toothache, dyspepsia, diarrhea, epilepsy and jaundice. The air-dried seed of the plant was completely immersed in water and subjected to hydro distillation for 3 h, using a clevenger-type apparatus. In this study, the effect of Cuminum cyminum L. essential oil (EO) on growth of Staphylococcus aureus in white brined cheese was evaluated. The experiment included different levels of EO (0, 7.5, 15 and 30 mL/ 100 mL milk) to assess their effects on S. aureus count during the manufacture, ripening and storage of Iranian white brined cheese for up to 75 days. The significant (P < 0.05) inhibitory effects of EO (even at its lowest concentration) on this organism were observed. The significant (P < 0.05) inhibitory effect of the EO on S. aureus shown in this study may improve the scope of the EO function in the food industry.Keywords: cuminum cyminum L. essential oil, staphylococcus aureus, white brined cheese
Procedia PDF Downloads 3913054 Development of Rh/Ce-Zr-La/Al2O3 TWCs’ Wash Coat: Effect of Reactor on Catalytic and Thermal Stability
Authors: Su-Ning Wang, Yao-Qiang Chen
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The CeO2-ZrO2-La2O3-Al2O3 composite oxides are synthesized using co-precipitation method by two different reactors (i.e. continuous stirred-tank reactor and batch reactor), and the corresponding Rh-only three-way catalysts are obtained by wet-impregnation approach. The textural, structural, morphology and redox properties of the support materials, as well as the catalytic performance of the Rh-only catalyst are investigated systematically. The results reveal that the materials (CZLA-C) synthesized by continuous stirred-tank reactor have a better physic-chemical properties than the counterpart material (CZLA-B) prepared by batch reactor. After aging treatment at 1000 ℃ for 5 h, the BET surface area and pore volume of S1 reach up to 76 m2 g-1 and 0.36 mL/g, respectively, which is higher than that of S2. The XRD and Raman results demonstrate that a high structural stability is obtained by S1 because of the negligible lattice variation and the slight grain growth after aging treatment. The SEM and TEM images display that the morphology of S1 is assembled by many homogeneous primary nanoparticles (about 6.12 nm) that are connected to form mesoporous structure The TPR measurement shows that S1 possesses a higher reduction ability than S2. Compared with the catalyst supported on the CZLA-B, the as-prepared CZLA-C demonstrates an improved three-way catalytic activity both before and after aging treatment.Keywords: composite oxides, reactor, catalysis, catalytic performance
Procedia PDF Downloads 3003053 Characterization and Modelling of Groundwater Flow towards a Public Drinking Water Well Field: A Case Study of Ter Kamerenbos Well Field
Authors: Buruk Kitachew Wossenyeleh
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Groundwater is the largest freshwater reservoir in the world. Like the other reservoirs of the hydrologic cycle, it is a finite resource. This study focused on the groundwater modeling of the Ter Kamerenbos well field to understand the groundwater flow system and the impact of different scenarios. The study area covers 68.9Km2 in the Brussels Capital Region and is situated in two river catchments, i.e., Zenne River and Woluwe Stream. The aquifer system has three layers, but in the modeling, they are considered as one layer due to their hydrogeological properties. The catchment aquifer system is replenished by direct recharge from rainfall. The groundwater recharge of the catchment is determined using the spatially distributed water balance model called WetSpass, and it varies annually from zero to 340mm. This groundwater recharge is used as the top boundary condition for the groundwater modeling of the study area. During the groundwater modeling using Processing MODFLOW, constant head boundary conditions are used in the north and south boundaries of the study area. For the east and west boundaries of the study area, head-dependent flow boundary conditions are used. The groundwater model is calibrated manually and automatically using observed hydraulic heads in 12 observation wells. The model performance evaluation showed that the root means the square error is 1.89m and that the NSE is 0.98. The head contour map of the simulated hydraulic heads indicates the flow direction in the catchment, mainly from the Woluwe to Zenne catchment. The simulated head in the study area varies from 13m to 78m. The higher hydraulic heads are found in the southwest of the study area, which has the forest as a land-use type. This calibrated model was run for the climate change scenario and well operation scenario. Climate change may cause the groundwater recharge to increase by 43% and decrease by 30% in 2100 from current conditions for the high and low climate change scenario, respectively. The groundwater head varies for a high climate change scenario from 13m to 82m, whereas for a low climate change scenario, it varies from 13m to 76m. If doubling of the pumping discharge assumed, the groundwater head varies from 13m to 76.5m. However, if the shutdown of the pumps is assumed, the head varies in the range of 13m to 79m. It is concluded that the groundwater model is done in a satisfactory way with some limitations, and the model output can be used to understand the aquifer system under steady-state conditions. Finally, some recommendations are made for the future use and improvement of the model.Keywords: Ter Kamerenbos, groundwater modelling, WetSpass, climate change, well operation
Procedia PDF Downloads 1583052 The Mechanism of Design and Analysis Modeling of Performance of Variable Speed Wind Turbine and Dynamical Control of Wind Turbine Power
Authors: Mohammadreza Heydariazad
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Productivity growth of wind energy as a clean source needed to achieve improved strategy in production and transmission and management of wind resources in order to increase quality of power and reduce costs. New technologies based on power converters that cause changing turbine speed to suit the wind speed blowing turbine improve extraction efficiency power from wind. This article introduces variable speed wind turbines and optimization of power, and presented methods to use superconducting inductor in the composition of power converter and is proposed the dc measurement for the wind farm and especially is considered techniques available to them. In fact, this article reviews mechanisms and function, changes of wind speed turbine according to speed control strategies of various types of wind turbines and examines power possible transmission and ac from producing location to suitable location for a strong connection integrating wind farm generators, without additional cost or equipment. It also covers main objectives of the dynamic control of wind turbines, and the methods of exploitation and the ways of using it that includes the unique process of these components. Effective algorithm is presented for power control in order to extract maximum active power and maintains power factor at the desired value.Keywords: wind energy, generator, superconducting inductor, wind turbine power
Procedia PDF Downloads 329