Search results for: acid number

Authors: Jehad Dumireih, Malak Dmirieh, Michael Wink

Abstract:

The present work is aimed to use plant cell suspension cultures of Crataegus monogyna for biosynthesis of valuable natural products by using quercetin as an inexpensive precursor. Suspension cell cultures of C. monogyna were established by using Murashige and Skoog medium (MS) supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid and 1 mg/L kinetin. Cells were harvested from the cultures and extracted by using methanol and ethyl acetate; then the extracts were used for the identification of isoquercetin by HPLC and by mass spectrometry. The incubation of the cells with 0.24 mM quercetin for one week resulted in an 16 fold increase of isoquercetin biosynthesis; the growth rate of the cells increased by 20%. Moreover, the biosynthesis of isoquercetin was enhanced by 40% when we divided the added quercetin into three portions each one with concentration 0.12 mM supplied at 3 days intervals. In addition, we didn’t find any positive effects of adding different concentrations the precursors phenylalanine (0.2 mM) and galactose to the cell cultures. In conclusion, the efficiency of the biotransformation of quercetin into isoquercetin depended on the concentration quercetin, its incubation time and the way of its administration. The results of the present work suggest that the biotechnological methods such as cell suspension cultures could be successfully used to obtain highly valuable natural product starting from inexpensive compound.

Keywords: biosynthesis, biotransformation, Crataegus, isoquercetin

Procedia PDF Downloads 480

Authors: Mohammed A. Elhaj, Jamal S. Yassin

Abstract:

Owing to the lack of synchronization between the solar energy availability and the heat demands in a specific application, the energy storing sub-system is necessary to maintain the continuity of thermal process. The present work is dealing with an active solar heating storing system in which an air solar collector is connected to storing unit where this energy is distributed and provided to the heated space in a controlled manner. The solar collector is a box type absorber where the air flows between a number of vanes attached between the collector absorber and the bottom plate. This design can improve the efficiency due to increasing the heat transfer area exposed to the flowing air, as well as the heat conduction through the metal vanes from the top absorbing surface. The storing unit is a packed bed type where the air is coming from the air collector and circulated through the bed in order to add/remove the energy through the charging / discharging processes, respectively. The major advantage of the packed bed storage is its high degree of thermal stratification. Numerical solution of the packed bed energy storage is considered through dividing the bed into a number of equal segments for the bed particles and solved the energy equation for each segment depending on the neighbor ones. The studied design and performance parameters in the developed simulation model including, particle size, void fraction, etc. The final results showed that the collector efficiency was fluctuated between 55%-61% in winter season (January) under the climatic conditions of Misurata in Libya. Maximum temperature of 52ºC is attained at the top of the bed while the lower one is 25ºC at the end of the charging process of hot air into the bed. This distribution can satisfy the required load for the most house heating in Libya.

Keywords: solar energy, thermal process, performance, collector, packed bed, numerical analysis, simulation

Procedia PDF Downloads 313

Authors: Sobhy M. Mohsen, Mohamed M. El-Nikeety, Tarek G. Mohamed, Michael Murkovic

Abstract:

The present work aimed to study the use of ohmic heating in the processing of mango pulp comparing to conventional method. Mango pulp was processed by using ohmic heating under the studied suitable conditions. Physical, chemical and microbiological properties of mango pulp were studied. The results showed that processing of mango pulp by using either ohmic heating or conventional method caused a decrease in the contents of TSS, total carbohydrates, total acidity, total sugars (reducing and non-reducing sugar) and an increase in phenol content, ascorbic acid and carotenoids compared to the conventional process. The increase in electric conductivity of mango pulp during ohmic heating was due to the addition of some electrolytes (salts) to increase the ions and enhance the process. The results also indicate that mango pulp processed by ohmic heating contained more phenols, carbohydrates and vitamin C and less HMF compared to that produced by conventional one. Total pectin and its fractions had slightly reduced by ohmic heating compared to conventional method. Enzymatic activities showed a reduction in poly phenoloxidase (PPO) and polygalacturonase (PG) activity in mango pulp processed by conventional method. However, ohmic heating completely inhibited PPO and PG activities.

Keywords: ohmic heating, mango pulp, phenolic, sarotenoids

Procedia PDF Downloads 442

Authors: A. Morina, S. Ö. Muti, M. Öztürk

Abstract:

Celiac disease is a chronic intestinal disease observed in individuals with gluten intolerance. In this study, our aim was to create a protein matrix to mimic the functional properties of gluten. For this purpose, rennet casein and four emulsifying salts (disodium phosphate (DSP), tetrasodium pyrophosphate (TSPP), sodium acid pyrophosphate (SAPP), and sodium hexametaphosphate (SHMP)) were investigated in gluten-free bread manufacture. Compositional, textural, and visual properties of the gluten-free bread dough and gluten-free breads were investigated by a two–level factorial experimental design with two-star points (α = 1.414) and two replicates of the center point. Manufacturing gluten-free bread with rennet casein and SHMP significantly increased the bread volume (P < 0.0001, R² = 97.8). In general, utilization of rennet casein with DSP and SAPP increased bread hardness while no difference was observed in samples manufactured with TSPP and SHMP. Except for TSPP, bread color was improved by the utilization of rennet casein and DSP, SAPP, and SHMP combinations. In conclusion, it is possible to manufacture gluten-free bread with acceptable texture and color by rennet casein and SHMP.

Keywords: celiac disease, gluten-free bread, emulsified salts, rennet casein, rice flour

Procedia PDF Downloads 147

Authors: Laxman H. Surwase, Lalit V. Sonawane, Bhagwat N. Poul

Abstract:

A simple stability indicating high performance liquid chromatographic method has been developed for the simultaneous determination of Levosalbutamol Sulphate and Ipratropium Bromide in bulk and pharmaceutical dosage form using reverse phase Zorbax Eclipse Plus C8 column (250mm×4.6mm), with mobile phase phosphate buffer (0.05M KH2PO4): acetonitrile (55:45v/v) pH 3.5 adjusted with ortho-phosphoric acid, the flow rate was 1.0 mL/min and the detection was carried at 212 nm. The retention times of Levosalbutamol Sulphate and Ipratropium Bromide were 2.2007 and 2.6611 min respectively. The correlation coefficient of Levosalbutamol Sulphate and Ipratropium Bromide was found to be 0.997 and 0.998.Calibration plots were linear over the concentration ranges 10-100µg/mL for both Levosalbutamol Sulphate and Ipratropium Bromide. The LOD and LOQ of Levosalbutamol Sulphate were 2.520µg/mL and 7.638µg/mL while for Ipratropium Bromide was 1.201µg/mL and 3.640 µg/mL. The accuracy of the proposed method was determined by recovery studies and found to be 100.15% for Levosalbutamol Sulphate and 100.19% for Ipratropium Bromide respectively. The method was validated for accuracy, linearity, sensitivity, precision, robustness, system suitability. The proposed method could be utilized for routine analysis of Levosalbutamol Sulphate and Ipratropium Bromide in bulk and pharmaceutical capsule dosage form.

Keywords: levosalbutamol sulphate, ipratropium bromide, RP-HPLC, phosphate buffer, acetonitrile

Procedia PDF Downloads 334

Authors: Takamitsu Kodama, Eiji Kawamoto

Abstract:

Introduction: Ultrasound in emergency room has advantages of safer, faster, repeatable and noninvasive. Especially focused Point-Of-Care Ultrasound (POCUS) is used daily for prompt and accurate diagnoses, for quickly identifying critical and life-threatening conditions. That is why ultrasound has demonstrated its usefulness in emergency medicine. The true value of ultrasound has been once again recognized in recent years. It is thought that all resident physicians working at emergency room should perform an ultrasound scan to interpret signs and symptoms of deteriorating patients in the emergency room. However, a practical education on ultrasound is still in development. To resolve this issue, we established a new educational program using high-fidelity simulators and evaluated the efficacy of this course. Methods: Educational program includes didactic lectures and skill stations in half-day course. Instructor gives a lecture on POCUS such as Rapid Ultrasound in Shock (RUSH) and/or Focused Assessment Transthoracic Echo (FATE) protocol at the beginning of the course. Then, attendees are provided for training of scanning with cooperation of normal simulated patients. In the end, attendees learn how to apply focused POCUS skills at clinical situation using high-fidelity simulators such as SonoSim® (SonoSim, Inc) and SimMan® 3G (Laerdal Medical). Evaluation was conducted through surveillance questionnaires to 19 attendees after two pilot courses. The questionnaires were focused on understanding course concept and satisfaction. Results: All attendees answered the questionnaires. With respect to the degree of understanding, 12 attendees (number of valid responses: 13) scored four or more points out of five points. High-fidelity simulators, especially SonoSim® was highly appreciated to enhance learning how to handle ultrasound at an actual practice site by 11 attendees (number of valid responses: 12). All attendees encouraged colleagues to take this course because the high level of satisfaction was achieved. Discussion: Newly introduced educational course using high-fidelity simulators realizes the circle of learning to deepen the understanding on focused POCUS by gradual stages. SonoSim® can faithfully reproduce scan images with pathologic findings of ultrasound and provide experimental learning for a growth number of beginners such as resident physicians. In addition, valuable education can be provided if it is used combined with SimMan® 3G. Conclusions: Newly introduced educational course using high-fidelity simulators is supposed to be effective and helps in providing better education compared with conventional courses for emergency physicians.

Keywords: point-of-care ultrasound, high-fidelity simulators, education, circle of learning

Procedia PDF Downloads 267

Authors: Sungpyo Kim, Changseok Oh, Ga-Young Lee, Hyun-Man Kim

Abstract:

Intercellular junction of keratinocytes is crucial for epithelia to build an epithelial barrier. Junctional epithelium (JE) seals the interfaces between tooth and gingival tissue. Keratinocytes of JE attach to surfaces roughened by abrasion or erosion with aging. Thus behavior of oral keratinocytes on the rough substrates may help understand the epithelial seal of JE of which major intercellular junction is E-cadherin junction (ECJ). The present study investigated the influence of various substrate roughnesses on the development of ECJ between normal human gingival epithelial keratinocytes, HOK-16B cells. HOK-16B cells were slow in the development of ECJ on the rough substrates compared to on the smooth substrates. Furthermore, oral keratinocytes on the substrates of higher roughnesses were delayed in the development of E-cadherin junction than on the substrates of lower roughnesses. Delayed development of E-cadherin junction on the rough substrates was ascribed to the impaired spreading of cells and its higher JNK activity. Cells on the smooth substrates rapidly spread wide cytoplasmic extensions around cells. However, cells on the rough substrates slowly extended narrow cytoplasmic extensions of which number was limited due to the substrate irregularity. As these cytoplasmic extensions formed ECJ when met with the extensions of neighboring cells, thus, the present study demonstrated that a limited chance of contacts between cytoplasmic extensions due to the limited number of cytoplasmic extensions and slow development of cytoplasmic extensions brought about a delayed development of ECJ in oral keratinocytes on the rougher substrates. Sealing between cells was not complete because only part of cell membrane contributes to the formation of intercellular junction between cells on the substrates of higher roughnesses. Interestingly, inhibition of JNK activity promoted the development of ECJ on the rough substrates, of which mechanism remains to be studied further.

Keywords: substrate roughness, E-cadherin junction, oral keratinocyte, cell spreading, JNK

Procedia PDF Downloads 367

Authors: Prativa Das, Lay Poh Tan

Abstract:

Three-dimensional microenvironment is a need to study the event cascades of liver fibrosis in vitro. Electrospun nanofibers modified with essential extracellular matrix proteins can closely mimic the random fibrous structure of native liver extracellular matrix (ECM). In this study, we fabricate a series of 3D electrospun scaffolds by wet electrospinning process modified with different ratios of collagen-I to fibronectin to achieve optimized distribution of these two ECM proteins on the fiber surface. A ratio of 3:1 of collagen-I to fibronectin was found to be optimum for surface modification of electrospun poly(lactic-co-glycolic acid) (PLGA) fibers by chemisorption process. In 3:1 collagen-I to fibronectin modified scaffolds the total protein content increased by ~2 fold compared to collagen-I modified and ~1.5 fold compared to 1:1/9:1 collagen-I to fibronectin modified scaffolds. We have cultured LX-2 cells on this scaffold over 14 days and found that LX-2 cells acquired more quiescent phenotype throughout the culture period and shown significantly lower expression of alpha smooth muscle actin and collagen-I. Thus, this system can be used as a model to study liver fibrosis by using different fibrogenic mediators in vitro.

Keywords: electrospinning, collagen-I and fibronectin, surface modification of fiber, LX-2 cells, liver fibrosis

Procedia PDF Downloads 113

Authors: Mounir Baccar, Imen Jmal

Abstract:

Because of the rise in energy costs, thermal storage systems designed for the heating and cooling of buildings are becoming increasingly important. Energy storage can not only reduce the time or rate mismatch between energy supply and demand but also plays an important role in energy conservation. One of the most preferable storage techniques is the Latent Heat Thermal Energy Storage (LHTES) by Phase Change Materials (PCM) due to its important energy storage density and isothermal storage process. This paper presents a numerical study of the solidification of a PCM (paraffin RT27) in a rectangular thermal storage exchanger for air conditioning systems taking into account the presence of natural convection. Resolution of continuity, momentum and thermal energy equations are treated by the finite volume method. The main objective of this numerical approach is to study the effect of natural convection on the PCM solidification time and the impact of fins number on heat transfer enhancement. It also aims at investigating the temporal evolution of PCM solidification, as well as the longitudinal profiles of the HTF circling in the duct. The present research undertakes the study of two cases: the first one treats the solidification of PCM in a PCM-air heat exchanger without fins, while the second focuses on the solidification of PCM in a heat exchanger of the same type with the addition of fins (3 fins, 5 fins, and 9 fins). Without fins, the stratification of the PCM from colder to hotter during the heat transfer process has been noted. This behavior prevents the formation of thermo-convective cells in PCM area and then makes transferring almost conductive. In the presence of fins, energy extraction from PCM to airflow occurs at a faster rate, which contributes to the reduction of the discharging time and the increase of the outlet air temperature (HTF). However, for a great number of fins (9 fins), the enhancement of the solidification process is not significant because of the effect of confinement of PCM liquid spaces for the development of thermo-convective flow. Hence, it can be concluded that the effect of natural convection is not very significant for a high number of fins. In the optimum case, using 3 fins, the increasing temperature of the HTF exceeds approximately 10°C during the first 30 minutes. When solidification progresses from the surfaces of the PCM-container and propagates to the central liquid phase, an insulating layer will be created in the vicinity of the container surfaces and the fins, causing a low heat exchange rate between PCM and air. As the solid PCM layer gets thicker, a progressive regression of the field of movements is induced in the liquid phase, thus leading to the inhibition of heat extraction process. After about 2 hours, 68% of the PCM became solid, and heat transfer was almost dominated by conduction mechanism.

Keywords: heat transfer enhancement, front solidification, PCM, natural convection

Procedia PDF Downloads 173

Authors: Hong Geng, Zaiyu Fan

Abstract:

With the acceleration of urbanization and motorization in China, the scale of cities and the travel distance of residents are constantly expanding, and the number of cars is continuously increasing, so the urban traffic problem is more and more serious. Traffic congestion, environmental pollution, energy consumption, travel safety and direct interference between traffic and other urban activities are increasingly prominent problems brought about by motorized development. This not only has a serious impact on the lives of the residents but also has a major impact on the healthy development of the city. The paper found that, in order to solve the development of motorization, a number of problems will arise; urban planning and traffic planning and design in residential planning often take into account the development of motorized traffic but neglects the demand for street life. This kind of planning has resulted in the destruction of the traditional communication space of the residential area, the pollution of noise and exhaust gas, and the potential safety risks of the residential area, which has disturbed the previously quiet and comfortable life of the residential area, resulting in the inconvenience of residents' life and the loss of street vitality. Based on these facts, this paper takes a residential area in Wuhan as the research object, through the actual investigation and research, from the perspective of micro-transformation analysis, combined with the concept of traffic micro-reconstruction governance. And research puts forward the residential traffic optimization strategies such as strengthening the interaction and connection between the residential area and the urban street system, street traffic classification and organization.

Keywords: micro-transformation, residential traffic, residents demand, traffic microcirculation

Procedia PDF Downloads 103

Authors: N. Belhadj, M. Hadj Youcef, T. Benabdallah, Belbachir Ibtissem, N. Boceiri

Abstract:

This work deals with the synthesis, the structural elucidation and the exploration the extracting properties of a series of ortho-hydroxy Schiff base in sulfate medium. After the synthesis and characterization of their structures, the study of their behavior in solution was carried out by pH-metric titration in different media homogeneous and heterogeneous solution. This allowed to explore and to quantify in each of these media, some of their properties in solution such as, their acid-base behavior (determination and comparison of pKa), their distribution powers (determination and comparison of logKd), and their thermodynamic constants (determining ∆H°, ΔS° and ∆G°moy) by optimizing both the temperature and ionic strength. Study of the extraction of nickel (II) and cobalt(II) separately was undertaken in the aqueous-organic system, chloroform-water. Different extraction parameters have been thus optimized such, the pH, the concentration of extractant and the ionic strength, and the extraction constants established in each case. The extracted metal complexes have been isolated and their spatial configurations elucidated. The selective extraction of the couple cobalt (II)/nickel (II) was finally performed by our series of Schiff base in the chloroforme/water.

Keywords: selective extraction, Schiff base, distribution, cobalt(II), nickel(II)

Procedia PDF Downloads 449

Authors: Rabeb Triki, Hassene Djemel, Mounir Baccar

Abstract:

Surface scraping is a passive heat transfer enhancement technique that is directly used in scraped surface heat exchanger (SSHE). The scraping action prevents the accumulation of the product on the inner wall, which intensifies the heat transfer and avoids the formation of dead zones. SSHEs are widely used in industry for several applications such as crystallization, sterilization, freezing, gelatinization, and many other continuous processes. They are designed to deal with products that are viscous, sticky or that contain particulate matter. This research work presents a three-dimensional numerical simulation of the coupled thermal and hydrodynamic behavior within a SSHE which includes Archimedes’ screw instead of scraper blades. The finite volume Fluent 15.0 was used to solve continuity, momentum and energy equations using multiple reference frame formulation. The process fluid investigated under this study is the pure glycerin. Different geometrical parameters were studied in the case of steady, non-isothermal, laminar flow. In particular, attention is focused on the effect of the conicity of the rotor and the pitch of Archimedes’ screw on temperature and velocity distribution and heat transfer rate. Numerical investigations show that the increase of the number of turns in the screw from five to seven turns leads to amelioration of heat transfer coefficient, and the increase of the conicity of the rotor from 0.1 to 0.15 leads to an increase in the rate of heat transfer. Further studies should investigate the effect of different operating parameters (axial and rotational Reynolds number) on the hydrodynamic and thermal behavior of the SSHE.

Keywords: ANSYS-Fluent, hydrodynamic behavior, scraped surface heat exchange, thermal behavior

Procedia PDF Downloads 148

Authors: Andrea Marcela Morales Reyes

Abstract:

In the year 2000, the federal government of the United States of America enacted anti-trafficking legislation to prevent human trafficking, prosecute traffickers, and protect the victims. Since then, all 50 states have followed the federal government's example by enacting state-level anti-trafficking legislation. In order to fight human trafficking in the United States, it is paramount that this legislation is not only comprehensively enacted but also enforced. This study reviewed the anti-trafficking laws enacted in each of the 50 states and investigated the success of such laws by reporting the number of trafficking related prosecutions, cases identified, and victims protected. This study reviewed human trafficking reports issued by nonprofits, and state and federal level agencies. An increase in the number of cases investigated since the state laws have been passed reflects a moderate success in the fight against human trafficking in the U.S. This review also found that although every state has passed anti-trafficking legislation, many still lack a comprehensive approach to combat human trafficking; some states lack key provisions to prevent human trafficking, prosecute traffickers, and protect it victims. This, along with the lack of enforcement of the anti-trafficking plans included in each of the state legislations, has meant that the human trafficking cases investigated in fiscal year 2016 are not near the estimated numbers; which in turn suggests that this crime is still greatly unaccounted for. This study concludes that although important steps have been taken at the national and state level to combat human trafficking, the identification and prosecution of human trafficking cases still proves challenging in the United States.

Keywords: enforcement of laws, human trafficking, anti-trafficking legislation, United States

Procedia PDF Downloads 150

Authors: Xia Huo

Abstract:

The composition and metabolites of the gut microbiota can be altered by environmental pollutants. However, the effect of co-exposure to multiple pollutants on the human gut microbiota has not been sufficiently studied. In this study, gut microorganisms and their metabolites were compared between 33 children from Guiyu and 34 children from Haojiang. The exposure level was assessed by estimating the daily intake (EDI) of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), 6PPD-quinone (6PPDQ), and metal(loid)s in dust. Significant correlations were found between the EDIs of 6PPDQ, BDE28, PCB52, Ni, Cu, and both the alpha diversity index and specific metabolites in single-element models. The study found that the Bayesian kernel machine regression (BKMR) model showed a negative correlation between the EDIs of five pollutants (6PPDQ, BDE28, PCB52, Ni, and Cu) and the Chao 1 index, particularly beyond the 55th percentile. Furthermore, the EDIs of these five pollutants were positively correlated with the levels of the metabolite 2,4-diaminobutyric acid while negatively correlated with the levels of d-erythro-sphingosine and d-threitol. Our research suggests that exposure to 6PPDQ, BDE28, PCB52, Ni, and Cu in kindergarten dust is associated with alterations in the gut microbiota and its metabolites. These alterations may be associated with neurodevelopmental abnormalities in children.

Keywords: gut microbiota, 6PPDQ, PBDEs, PCBs, metal(loid)s, BKMR

Procedia PDF Downloads 41

Authors: Fabienne Baraud, Lydia Leleyter, Sandra Poree, Melanie Lemoine

Abstract:

SEDIBRIC (valorization de SEDIments en BRIQues et tuiles) is a French project that aims to replace a part of natural clays with dredged sediments in the preparation of fired bricks in order to propose an alternative solution for the management of harbor dredged sediments. The feasibility of such re-use is explored from a technical, economic, and environmental point of view. The present study focuses on the potential environmental impact of various chemical elements (Al, Ca, Cd, Co, Cr, Cu, Fe, Ni, Mg, Mn, Pb, Ti, and Zn) that are initially present in the dredged sediments. The total content (after acid digestion) and the environmental availability (estimated by single extractions with various extractants) of these elements are determined in the raw sediments and in the obtained fired bricks. The possible influence of some steps of the manufacturing process (sediment pre-treatment, firing) is also explored. The first results show that the pre-treatment step, which uses tap water to desalinate the raw sediment, does not influence the environmental availability of the studied elements. However, the firing process, performed at 900°C, can affect the amount of some elements detected in the bricks, as well as their environmental availability. We note that for Cr, or Ni, the HCl or EDTA availability was increased in the brick (compared to the availability in the raw sediment). For Cd, Cu, Pb, and Zn, the HCl and EDTA availability was reduced in the bricks, meaning that these elements were stabilized within the bricks.

Keywords: bricks, chemical extraction, metals, sediment

Procedia PDF Downloads 135

Authors: Miguel Chen Austin, Denis Bruneau, Alain Sempey, Laurent Mora, Alain Sommier

Abstract:

An experimental study in a Plus Energy House (PEH) prototype was conducted in August 2016. It aimed to highlight the energy charge and discharge of a concrete-slab floor submitted to the day-night-cycles heat exchanges in the southwestern part of France and to identify the heat transfer phenomena that take place in both processes: charge and discharge. The main features of this PEH, significant to this study, are the following: (i) a non-active slab covering the major part of the entire floor surface of the house, which include a concrete layer 68 mm thick as upper layer; (ii) solar window shades located on the north and south facades along with a large eave facing south, (iii) large double-glazed windows covering the majority of the south facade, (iv) a natural ventilation system (NVS) composed by ten automatized openings with different dimensions: four are located on the south facade, four on the north facade and two on the shed roof (north-oriented). To highlight the energy charge and discharge processes of the non-active slab, heat flux and temperature measurement techniques were implemented, along with airspeed measurements. Ten “measurement-poles” (MP) were distributed all over the concrete-floor surface. Each MP represented a zone of measurement, where air and surface temperatures, and convection and radiation heat fluxes, were intended to be measured. The airspeed was measured only at two points over the slab surface, near the south facade. To identify the heat transfer phenomena that take part in the charge and discharge process, some relevant dimensionless parameters were used, along with statistical analysis; heat transfer phenomena were identified based on this analysis. Experimental data, after processing, had shown that two periods could be identified at a glance: charge (heat gain, positive values) and discharge (heat losses, negative values). During the charge period, on the floor surface, radiation heat exchanges were significantly higher compared with convection. On the other hand, convection heat exchanges were significantly higher than radiation, in the discharge period. Spatially, both, convection and radiation heat exchanges are higher near the natural ventilation openings and smaller far from them, as expected. Experimental correlations have been determined using a linear regression model, showing the relation between the Nusselt number with relevant parameters: Peclet, Rayleigh, and Richardson numbers. This has led to the determination of the convective heat transfer coefficient and its comparison with the convective heat coefficient resulting from measurements. Results have shown that forced and natural convection coexists during the discharge period; more accurate correlations with the Peclet number than with the Rayleigh number, have been found. This may suggest that forced convection is stronger than natural convection. Yet, airspeed levels encountered suggest that it is natural convection that should take place rather than forced convection. Despite this, Richardson number values encountered indicate otherwise. During the charge period, air-velocity levels might indicate that none air motion occurs, which might lead to heat transfer by diffusion instead of convection.

Keywords: heat flux measurement, natural ventilation, non-active concrete slab, plus energy house

Procedia PDF Downloads 403

Authors: Arfan Ali, Idrees Ahmad Nasir

Abstract:

The critical evaluation of tolerance in tomato plants against the induced saline soil were assessed by transcript analysis of genes coding for products potentially involved in stress tolerance. A reverse transcriptase PCR experiment was performed with Hsp90-1, MT2, and GR1like protein genes using RNA isolated from different tissues of tomato plants. Four strains of Bacillus magisterium were inoculated with 100 Mm & 200 Mm concentrations of salt. Eleven treatments each ten replica pots were installed in green house experiment and the parameters taken into account were morphological (length, weight, number of leaves, leaf surface area), chemical (anthocyanin, chlorophyll-a, chlorophyll-b, carotenoids) and biological (gene expression). Results bare a response i.e. highest response of MT2 like gene was at 24 hpi and the highest levels of GR1 like protein transcript accumulation were detected at 36 hpi. The chemical and morphological parameters at diverse salt concentrations bequeath superlative response amongst strains which candidly flank on Zm7 and Zm4. Therefore, Bacillus magisterium Zm7 strains and somehow Zm4 strain can be used in saline condition to make plants tolerant. The overall performance of strains Zm7, Zm6, and Zm4 was found better for all studied traits under salt stress conditions. Significant correlations among traits root length, shoot length, number of leaves, leaf surface area, carotenoids, anthocyanin, chlorophyll-a and chlorophyll-b were found and suggested that the salt tolerance in tomato may be improved through the use of PGPR strains.

Keywords: Bacillus magisterium, gene expression glutathione reductase, metallothionein, PGPR, Rhizobacteria, saline

Procedia PDF Downloads 421

Authors: Yuxuan Huang, Weixin Qian, Hongfang Ma, Haitao Zhang, Weiyong Ying

Abstract:

Light olefins are important building blocks for chemical industry. Direct conversion of syngas to light olefins has been investigated for decades. Meanwhile, the limit for light olefins selectivity described by Anderson-Schulz-Flory (ASF) distribution model is still a great challenge to conventional Fischer-Tropsch synthesis. The emerging strategy called oxide-zeolite concept (OX-ZEO) is a promising way to get rid of this limit. ZnCrO_x was prepared by co-precipitation method and (NH₄)₂CO₃ was used as precipitant. SAPO-34 was prepared by hydrothermal synthesis, and Tetraethylammonium hydroxide (TEAOH) was used as template, while silica sol, pseudo-boehmite, and phosphoric acid were Al, Si and P source, respectively. The bifunctional catalyst was prepared by mechanical mixing of ZnCrO_x and SAPO-34. Catalytic reactions were carried out under H₂/CO=2, 380 ℃, 1 MPa and 6000 mL·g_cat^-1·h^-1 in a fixed-bed reactor with a quartz lining. Catalysts were characterized by XRD, N₂ adsorption-desorption, NH₃-TPD, H₂-TPR, and CO-TPD. The addition of Al as structure promoter enhances CO conversion and selectivity to light olefins. Zn/Cr ratio, which decides the active component content and chemisorption property of the catalyst, influences CO conversion and selectivity to light olefins at the same time. C_2-4⁼ distribution of 86% among hydrocarbons at CO conversion of 14% was reached when Zn/Cr=1.5.

Keywords: light olefins, OX-ZEO, Syngas, ZnCrOₓ

Procedia PDF Downloads 166

Authors: Jared Beard, Ali Baheri

Abstract:

As autonomous systems become more prominent in society, ensuring their safe application becomes increasingly important. This is clearly demonstrated with autonomous cars traveling through a crowded city or robots traversing a warehouse with heavy equipment. Human environments can be complex, having high dimensional state and action spaces. This gives rise to two problems. One being that analytic solutions may not be possible. The other is that in simulation based approaches, searching the entirety of the problem space could be computationally intractable, ruling out formal methods. To overcome this, approximate solutions may seek to find failures or estimate their likelihood of occurrence. One such approach is adaptive stress testing (AST) which uses reinforcement learning to induce failures in the system. The premise of which is that a learned model can be used to help find new failure scenarios, making better use of simulations. In spite of these failures AST fails to find particularly sparse failures and can be inclined to find similar solutions to those found previously. To help overcome this, multi-fidelity learning can be used to alleviate this overuse of information. That is, information in lower fidelity can simulations can be used to build up samples less expensively, and more effectively cover the solution space to find a broader set of failures. Recent work in multi-fidelity learning has passed information bidirectionally using “knows what it knows” (KWIK) reinforcement learners to minimize the number of samples in high fidelity simulators (thereby reducing computation time and load). The contribution of this work, then, is development of the bidirectional multi-fidelity AST framework. Such an algorithm, uses multi-fidelity KWIK learners in an adversarial context to find failure modes. Thus far, a KWIK learner has been used to train an adversary in a grid world to prevent an agent from reaching its goal; thus demonstrating the utility of KWIK learners in an AST framework. The next step is implementation of the bidirectional multi-fidelity AST framework described. Testing will be conducted in a grid world containing an agent attempting to reach a goal position and adversary tasked with intercepting the agent as demonstrated previously. Fidelities will be modified by adjusting the size of a time-step, with higher-fidelity effectively allowing for more responsive closed loop feedback. Results will compare the single KWIK AST learner with the multi-fidelity algorithm with respect to number of samples, distinct failure modes found, and relative effect of learning after a number of trials.

Keywords: multi-fidelity reinforcement learning, multi-fidelity simulation, safety validation, falsification

Procedia PDF Downloads 140

Authors: Mahdi Almaky, Reda Hassanin, Benjamin Horrocks, Andrew Houlton

Abstract:

DNA-templated poly(N-substituted pyrrole)bipyridinium nanowires were synthesised at room temperature using the chemical oxidation method. The resulting CPs/DNA hybrids have been characterised using electronic and vibrational spectroscopic methods especially Ultraviolet-Visible (UV-Vis) spectroscopy and FTIR spectroscpy. The nanowires morphology was characterised using Atomic Force Microscopy (AFM). The electrical properties of the prepared nanowires were characterised using Electrostatic Force Microscopy (EFM), and measured using conductive AFM (c-AFM) and two terminal I/V technique, where the temperature dependence of the conductivity was probed. The conductivities of the prepared CPs/DNA nanowires are generally lower than PPy/DNA nanowires showingthe large effect on N-alkylation in decreasing the conductivity of the polymer, butthese are higher than the conductivity of their corresponding bulk films.This enhancement in conductivity could be attributed to the ordering of the polymer chains on DNA during the templating process. The prepared CPs/DNA nanowires were used as templates for the growth of copper nanowires at room temperature using aqueous solution of Cu(NO3)2as a source of Cu2+ and ascorbic acid as reducing agent. AFM images showed that these nanowires were uniform and continuous compared to copper nanowires prepared using the templating method directly onto DNA. Electrical characterization of the nanowires by c AFM revealed slight improvement in conductivity of these nanowires (Cu-CPs/DNA) compared to CPs/DNA nanowires before metallisation.

Keywords: templating, copper nanowires, polymer/DNA hybrid, chemical oxidation method

Procedia PDF Downloads 350

Authors: Ramin Mansouri

Abstract:

Due to the contrast of rivers discharge regime with water demands, one of the best ways to use water resources is to regulate the natural flow of the rivers and supplying water needs to construct dams. Optimal utilization of reservoirs, consideration of multiple important goals together at the same is of very high importance. To study about analyzing this method, statistical data of Bakhtiari and Roudbar dam over 46 years (1955 until 2001) is used. Initially an appropriate objective function was specified and using DE algorithm, the rule curve was developed. In continue, operation policy using rule curves was compared to standard comparative operation policy. The proposed method distributed the lack to the whole year and lowest damage was inflicted to the system. The standard deviation of monthly shortfall of each year with the proposed algorithm was less deviated than the other two methods. The Results show that median values for the coefficients of F and Cr provide the optimum situation and cause DE algorithm not to be trapped in local optimum. The most optimal answer for coefficients are 0.6 and 0.5 for F and Cr coefficients, respectively. After finding the best combination of coefficients values F and CR, algorithms for solving the independent populations were examined. For this purpose, the population of 4, 25, 50, 100, 500 and 1000 members were studied in two generations (G=50 and 100). result indicates that the generation number 200 is suitable for optimizing. The increase in time per the number of population has almost a linear trend, which indicates the effect of population in the runtime algorithm. Hence specifying suitable population to obtain an optimal results is very important. Standard operation policy had better reversibility percentage, but inflicts severe vulnerability to the system. The results obtained in years of low rainfall had very good results compared to other comparative methods.

Keywords: reservoirs, differential evolution, dam, Optimal operation

Procedia PDF Downloads 66

Authors: Sunil Kumar, Sandip Dhole, Deepak Salunke, Chung-ming Sun

Abstract:

Heterocycles bearing nitrogen, oxygen, and selenium are present in innumerable biologically active compounds. For instance, coumarin containing dicoumarol acts as naturally occurring anticoagulant. 2-Acylamido selenazole works as Store-Operated Calcium (SOC) channel regulator. Therefore, due to biologically significance of selenazole and coumarin and our quest to develop efficient methodologies for the synthesis of complex heterocycles, the trisubstituted angular isocoumarinoselenazole synthesis was proposed and achieved by starting from nitrobenzoic acid derivative, available commercially. Synthetic procedure involves three steps: i) the construction of 2-aminobenzoselenazoles, ii) their regioselective N-alkylation at position-2 and iii) alkyne insertion via Ru catalyzed C-H activation. Transition metal free synthesis of benzoselenazoles was successfully brought about by the addition/elimination reaction via intramolecular C-Se bond formation. In the next step, N-alkylation of selenazole furnished two regioisomers. Both the isomers exhibited different reactivity towards [4+2] alkyne annulation reaction. The fusion of α-pyrone ring on the benzo[1,3-d]selenazole skeleton was achieved via Ru(II)-catalyzed C-H activation and alkyne insertion. As evident from mechanism, the selenazole 'N' plays an important role for the experiential selectivity.

Keywords: alkylation, alkyne insertion, coumarin, selenazole

Procedia PDF Downloads 109

Authors: T. S. Olugbemi, T. S. Friday, O. O. Olusola

Abstract:

This experiment was carried out to assess the effect of different stocking densities and vitamin C supplementation on the performance of Japanese quails. Five hundred and twenty (520) unsexed quail birds of two (2) weeks of age were allotted randomly into nine (9) groups with 3 replicates each in a 3x3 factorial arrangement (3 stocking density levels and 3 graded vitamin C levels) with densities of 150, 120, 90 cm2/bird(11, 16, 21 birds). During the five weeks growing trial (2- 6 weeks), results showed that stocking density had significant effects on final weight (131.59g compared to 111.10g for the lowest), total and daily weight gain. No significance difference was observed for feed conversion ratio, age at first lay and first egg weight. Observations on haematological parameters (packed cell volume (PCV), total protein (TP), haemoglobin, red blood cell (RBC), lymphocyte, heterophil) on stocking density showed no significant differences. Vitamin C supplementation at 50mg/kg and 100mg/kg did not have any significant effect on the growth performance parameters of growing quails. Stocking density at 150cm2/bird had a better performance with or without vitamin C supplementation hence it is recommended that stocking rates of quails between the ages of 2 – 6 weeks should not be below 150cm2/bird.

Keywords: anti-oxidants, performance, stress, stocking density

Procedia PDF Downloads 632

Authors: Philippa C. Ojimelukwe, Felix C. Okpalanma, Emmanuel A. Mazi

Abstract:

The carotenoid content, vitamins (ascorbic acid, riboflavin, thiamin, niacin and vitamin K) and mineral contents (K, Ca, Mg, Zn and Fe) of raw, cooked (moist heat treatment) and stored Gnetum africanum and Pterocarpus mildbraedii leaves were investigated in the present research. Raw G. africanum contained higher total carotenoids (246.93µg/g edible portion) than P. mildbraedii (83.53µg/g edible portion) However, moist heat treatment significantly improved the total carotenoid content of P. mildbraedii. The carotenoid profiles of P. mildbraedii and G. africanum showed improved contents of beta cryptoxanthin , 9-cis, 11-cis and 13 cis beta carotenes due to moist heat treatment. Lutein contents of the two green leafy vegetables were quite high in raw, heat treated and stored samples. The two green leafy vegetables were good sources of vitamin K (118-120 µg). Moist heat treatment significantly (p < 0.05) increased the mineral contents of P.mildbraedii and G. africanum. The vitamin contents were reduced. Storage at ambient temperature (30oC) in the dark led to good retention of the minerals but not the vitamins.

Keywords: Gnetum africanum, Pterocarpus mildbraedii, carotenoid profile, vitamins, minerals

Procedia PDF Downloads 469

Authors: Stella O. Olubodun, George E. Eriyamremu

Abstract:

The study assessed the effect of crude oil applied at rates, 0, 2, 5, and 10% on the fractional chemical forms and availability of some metals in soils from Usen, Edo State, with no known crude oil contamination and soil from a crude oil spill site in Ubeji, Delta State, Nigeria. Three methods were used to determine the bioavailability of metals in the soils: maize (Zea mays) plant, EDTA and BCR sequential extraction. The sequential extract acid soluble fraction of the BCR extraction (most labile fraction of the soils, normally associated with bioavailability) were compared with total metal concentration in maize seedlings as a means to compare the chemical and biological measures of bioavailability. Total Fe was higher in comparison to other metals for the crude oil contaminated soils. The metal concentrations were below the limits of 4.7% Fe, 190mg/kg Cu and 720mg/kg Zn intervention values and 36mg/kg Cu and 140mg/kg Zn target values for soils provided by the Department of Petroleum Resources (DPR) guidelines. The concentration of the metals in maize seedlings increased with increasing rates of crude oil contamination. Comparison of the metal concentrations in maize seedlings with EDTA extractable concentrations showed that EDTA extracted more metals than maize plant.

Keywords: availability, crude oil contamination, EDTA, maize, metals

Procedia PDF Downloads 205

Authors: Jaomai Tungsiripat, Patompong Satapornpong

Abstract:

Allopurinol have been used to treat diseases that relating with the reduction of uric acid and be a treatment preventing the severity of, including gout, chronic kidney disease, chronic heart failure, and diabetes mellitus (type 2). However, allopurinol metabolites can cause a severe cutaneous adverse reaction (SCARs) consist of Drug Rash with Eosinophilia and Systemic Symptoms (DRESS) and Stevens-Johnson Syndrome(SJS)/Toxic Epidermal Necrolysis (TEN). Previous studies, we found only HLA-B*58:01 allele has a strongly association with allopurinol-induced SCARs in many populations: Han Chinese [P value = 4.7 x 10−24], European [P value <10−6], and Thai [P value <0.001].However, there was no update the frequency of HLA-B alleles and pharmacogenetics markers distribution in healthy Thais and support for screening before the initiation of treatment. The aim of this study was to investigate the prevalence of HLA-B*58:01 allele associated with allopurinol-induced SCARs in healthy Thai population. A retrospective study of 260 individual healthy subjects who living in Thailand. HLA-B were genotyped using sequence-specific oligonucleotides (PCR-SSOs).In this study, we identified the prevalence of HLA-B alleles consist ofHLA-B*46:01 (12.69%), HLA-B*15:02 (8.85%), HLA-B*13:01 (6.35%), HLA-B*40:01 (6.35%), HLA-B*38:02 (5.00%), HLA-B*51:01 (5.00%), HLA-B*58:01 (4.81%), HLA-B*44:03 (4.62%), HLA-B*18:01 (3.85%) and HLA-B*15:25 (3.08%). Therefore, the distribution of HLA-B*58:01 will support the clinical implementation and screening usage of allopurinol in Thai population.

Keywords: allopurinol, HLA-B*58: 01, Thai population, SCARs

Procedia PDF Downloads 125

Authors: Kingsley Izuagbe Ikeke, Abayomi O. Adetuyi

Abstract:

The study investigated the removal efficiency of crystal violet from aqueous solution using chitosan-charcoal composite as adsorbent. Deproteination was carried out by placing 200g of powdered snail shell in 4% w/v NaOH for 2hours. The sample was then placed in 1% HCl for 24 hours to remove CaCO3. Deacetylation was done by boiling in 50% NaOH for 2hours. 10% Oxalic acid was used to dissolve the chitosan before mixing with charcoal at 55°C to form the composite. The composite was characterized by Fourier Transform Infra-Red and Scanning Electron Microscopy measurements. The efficiency of adsorption was evaluated by varying pH of the solution, contact time, initial concentration and adsorbent dose. Maximum removal of crystal violet by composite and activated charcoal was attained at pH10 while maximum removal of crystal violet by chitosan was achieved at pH 8. The results showed that adsorption of both dyes followed the pseudo-second-order rate equation and fit the Langmuir and Freundlich isotherms. The data showed that composite was best suited for crystal violet removal and also did relatively well in the removal of alizarin red. Thermodynamic parameters such as enthalpy change (ΔHº), free energy change (ΔGº) and entropy change (ΔSº) indicate that adsorption process of Crystal Violet was endothermic, spontaneous and feasible respectively.

Keywords: crystal violet, chitosan−charcoal composite, extraction process, sorption

Procedia PDF Downloads 418

Authors: Philna Coetzee, Clara Msiza

Abstract:

In modern society, audit committees are seen as the custodians of accountability and the conscience of management and the board. But who holds the audit committee accountable for their actions or non-actions and how do we know what they are supposed to be doing and what they are doing? The purpose of this article is to provide greater insight into the latter part of this problem, namely, determine what best practises for audit committees and the disclosure of what is the realities are. In countries where governance is well established, the roles and responsibilities of the audit committee are mostly clearly guided by legislation and/or guidance documents, with countries increasingly providing guidance on this topic. With high cost involved to adhere to governance guidelines, the public (for public organisations) and shareholders (for private organisations) expect to see the value of their ‘investment’. For audit committees, the dividends on the investment should reflect in less fraudulent activities, less corruption, higher efficiency and effectiveness, improved social and environmental impact, and increased profits, to name a few. If this is not the case (which is reflected in the number of fraudulent activities in both the private and the public sector), stakeholders have the right to ask: where was the audit committee? Therefore, the objective of this article is to contribute to the body of knowledge by comparing the adherence of audit committee to best practices guidelines as stipulated in the King Report across public listed companies, national and provincial government departments, state-owned enterprises and local municipalities. After constructs were formed, based on the literature, factor analyses were conducted to reduce the number of variables in each construct. Thereafter, cluster analyses, which is an explorative analysis technique that classifies a set of objects in such a way that objects that are more similar are grouped into the same group, were conducted. The SPSS TwoStep Clustering Component was used, being capable of handling both continuous and categorical variables. In the first step, a pre-clustering procedure clusters the objects into small sub-clusters, after which it clusters these sub-clusters into the desired number of clusters. The cluster analyses were conducted for each construct and the measure, namely the audit opinion as listed in the external audit report, were included. Analysing 228 organisations' information, the results indicate that there is a clear distinction between the four spheres of business that has been included in the analyses, indicating certain strengths and certain weaknesses within each sphere. The results may provide the overseers of audit committees’ insight into where a specific sector’s strengths and weaknesses lie. Audit committee chairs will be able to improve the areas where their audit committee is lacking behind. The strengthening of audit committees should result in an improvement of the accountability of boards, leading to less fraud and corruption.

Keywords: audit committee disclosure, cluster analyses, governance best practices, strengths and weaknesses

Procedia PDF Downloads 149

Authors: Ying Qi Chan, Chunyu Li, Xu Rou Yoyo Ma, Yaya Li, Saber Khederzadeh

Abstract:

In the ever-evolving landscape of genome extraction protocols, the existing methodologies grapple with issues ranging from sub-optimal yields and compromised quality to time-intensive procedures and reliance on hazardous reagents, often necessitating substantial tissue quantities. This predicament is particularly challenging for scientists in developing countries, where resources are limited. Our investigation presents a protocol for the efficient extraction of high-yield RNA from various tissues such as muscle, insect, and plant samples. Noteworthy for its advantages, our protocol stands out as the safest, swiftest (completed in just 38 minutes), most cost-effective (coming in at a mere US$0.017), and highly efficient method in comparison to existing protocols. Notably, our method avoids the use of hazardous or toxic chemicals such as chloroform and phenol and enzymatic agents like RNase and Proteinase K. Our RNA extraction protocol has demonstrated clear advantages over other methods, including commercial kits, in terms of yield. This nucleic acid extraction protocol is more environmentally and research-friendly, suitable for a range of tissues, even in tiny volumes, hence facilitating various genetic diagnosis and researches across the globe.

Keywords: RNA extraction, rapid protocol, universal method, diverse tissues

Procedia PDF Downloads 61

Authors: Yogesh Bacchaw, Ashish Dabade

Abstract:

Nowadays oral health is raising concern in society. Acid producing microorganisms changes the oral pH and creates a favorable environment for microbial growth. This growth not only promotes dental decay but also bad breath. Generally Recognized As Safe (GRAS) listed component was incorporated in chewing gum as an antimicrobial agent. The chewing gum produced exhibited up to 9 hours of antimicrobial activity against oral microflora. The toxicity of GRAS component per RACC value of chewing gum was negligible as compared to actual toxicity level of GRAS component. The antibacterial efficiency of chewing gum was tested by using total plate count (TPC) and colony forming unit (CFU). Nine hours were required to microflora to reach TPC/CFU of before chewing gum consumption. This chewing gum not only provides mouth freshening activity but also helps in lowering dental decay, bad breath, and enamel whitening.

Keywords: colony forming unit (CFU), chewing gum, generally recognized as safe (GRAS), microbial growth, microorganisms, oral health, RACC, total plate count (TPC), antimicrobial agent, enamel whitening, oral pH

Procedia PDF Downloads 296