Search results for: coupled enzyme system of bioluminescence bacteria NAD(P)H:FMN-oxidoreductase–luciferase
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Search results for: coupled enzyme system of bioluminescence bacteria NAD(P)H:FMN-oxidoreductase–luciferase

19676 The Use of a Geographical Information System in the Field of Irrigation (Moyen-Chéliff)

Authors: Benhenni Abdellaziz

Abstract:

Irrigation is a limiting factor for agricultural production and socioeconomic development of many countries in the arid and semi-arid world. However, the sustainability of irrigation systems requires rational management of the water resource, which is becoming increasingly rare in these regions. The objective of this work is to apply a geographic information system (GIS) coupled with a model for calculating crop water requirements (CROPWATER) for the management of irrigation water in irrigated areas and offer managers an effective tool to better manage water resources in these areas. The application area of GIS is the irrigated perimeter of Western Middle Cheliff, which is located in a semi-arid region (Middle Cheliff). The scope in question is considerable agrarian dynamics and an increased need for irrigation of most crops.

Keywords: GIS, CROPWAT, irrigation, water management, middle cheliff

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19675 The Use of a Geographical Information System in the Field of Irrigation (Moyen-Chéliff)

Authors: Benhenni Abdellaziz

Abstract:

Irrigation is a limiting factor for agricultural production and socio-economic development of many countries in arid and semiarid in the world. However, the sustainability of irrigation systems requires a rational management of the water resource that is becoming increasingly rare in these regions. The objective of this work is to apply a geographic information system (GIS) coupled to a model for calculating crop water requirements (CROPWATER) for the management of irrigation water in irrigated area and offer managers with an effective tool to better manage water resources in these areas. The application area of GIS is the irrigated perimeter of Western Middle Cheliff which is located in a semi-arid region (Middle Cheliff). The scope in question is a considerable agrarian dynamics and an increased need for irrigation of most crops.

Keywords: geographical information, irrigation, economical, use rational

Procedia PDF Downloads 233
19674 Campylobacteriosis as a Zoonotic Disease

Authors: A. Jafarzadeh, G. R. Hashemi Tabar

Abstract:

Campylobacteriosis is caused by Campylobacter organisms. This is most commonly caused by C. jejuni, It is among the most common bacterial infections of humans, often a foodborne illness. It produces an inflammatory, sometimes bloody, diarrhea or dysentery syndrome, mostly including cramps, fever and pain. It is found in cattle, swine, and birds, where it is non-pathogenic. But the illness can also be caused by C. coli (also found in cattle, swine, and birds) C. upsaliensis (found in cats and dogs) and C. lari (present in seabirds in particular). Infection with a Campylobacter species is one of the most common causes of human bacterial gastroenteritis. For instance, an estimated 2 million cases of Campylobacter enteritis occur annually in the U.S., accounting for 5-7% of cases of gastroenteritis. Furthermore, in the United Kingdom during 2000 Campylobacter jejuni was involved in 77.3% in all cases of foodborne illness. 15 out of every 100,000 people are diagnosed with campylobacteriosis every year, and with many cases going unreported, up to 0.5% of the general population may unknowingly harbor Campylobacter in their gut annually. A large animal reservoir is present as well, with up to 100% of poultry, including chickens, turkeys, and waterfowl, having asymptomatic infections in their intestinal tracts. An infected chicken may contain up to 109 bacteria per 25 grams, and due to the installations, the bacteria is rapidly spread to other chicken. This vastly exceeds the infectious dose of 1000-10,000 bacteria for humans. In this article this disease is fully discussed in human and animals.

Keywords: campylobacteriosis, human, animal, zoonosis

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19673 What Are the Problems in the Case of Analysis of Selenium by Inductively Coupled Plasma Mass Spectrometry in Food and Food Raw Materials?

Authors: Béla Kovács, Éva Bódi, Farzaneh Garousi, Szilvia Várallyay, Dávid Andrási

Abstract:

For analysis of elements in different food, feed and food raw material samples generally a flame atomic absorption spectrometer (FAAS), a graphite furnace atomic absorption spectrometer (GF-AAS), an inductively coupled plasma optical emission spectrometer (ICP-OES) and an inductively coupled plasma mass spectrometer (ICP-MS) are applied. All the analytical instruments have different physical and chemical interfering effects analysing food and food raw material samples. The smaller the concentration of an analyte and the larger the concentration of the matrix the larger the interfering effects. Nowadays, it is very important to analyse growingly smaller concentrations of elements. From the above analytical instruments generally the inductively coupled plasma mass spectrometer is capable of analysing the smallest concentration of elements. The applied ICP-MS instrument has Collision Cell Technology (CCT) also. Using CCT mode certain elements have better detection limits with 1-3 magnitudes comparing to a normal ICP-MS analytical method. The CCT mode has better detection limits mainly for analysis of selenium (arsenic, germanium, vanadium, and chromium). To elaborate an analytical method for selenium with an inductively coupled plasma mass spectrometer the most important interfering effects (problems) were evaluated: 1) isobaric elemental, 2) isobaric molecular, and 3) physical interferences. Analysing food and food raw material samples an other (new) interfering effect emerged in ICP-MS, namely the effect of various matrixes having different evaporation and nebulization effectiveness, moreover having different quantity of carbon content of food, feed and food raw material samples. In our research work the effect of different water-soluble compounds furthermore the effect of various quantity of carbon content (as sample matrix) were examined on changes of intensity of selenium. So finally we could find “opportunities” to decrease the error of selenium analysis. To analyse selenium in food, feed and food raw material samples, the most appropriate inductively coupled plasma mass spectrometer is a quadrupole instrument applying a collision cell technique (CCT). The extent of interfering effect of carbon content depends on the type of compounds. The carbon content significantly affects the measured concentration (intensities) of Se, which can be corrected using internal standard (arsenic or tellurium).

Keywords: selenium, ICP-MS, food, food raw material

Procedia PDF Downloads 495
19672 A Laser Instrument Rapid-E+ for Real-Time Measurements of Airborne Bioaerosols Such as Bacteria, Fungi, and Pollen

Authors: Minghui Zhang, Sirine Fkaier, Sabri Fernana, Svetlana Kiseleva, Denis Kiselev

Abstract:

The real-time identification of bacteria and fungi is difficult because they emit much weaker signals than pollen. In 2020, Plair developed Rapid-E+, which extends abilities of Rapid-E to detect smaller bioaerosols such as bacteria and fungal spores with diameters down to 0.3 µm, while keeping the similar or even better capability for measurements of large bioaerosols like pollen. Rapid-E+ enables simultaneous measurements of (1) time-resolved, polarization and angle dependent Mie scattering patterns, (2) fluorescence spectra resolved in 16 channels, and (3) fluorescence lifetime of individual particles. Moreover, (4) it provides 2D Mie scattering images which give the full information on particle morphology. The parameters of every single bioaerosol aspired into the instrument are subsequently analysed by machine learning. Firstly, pure species of microbes, e.g., Bacillus subtilis (a species of bacteria), and Penicillium chrysogenum (a species of fungal spores), were aerosolized in a bioaerosol chamber for Rapid-E+ training. Afterwards, we tested microbes under different concentrations. We used several steps of data analysis to classify and identify microbes. All single particles were analysed by the parameters of light scattering and fluorescence in the following steps. (1) They were treated with a smart filter block to get rid of non-microbes. (2) By classification algorithm, we verified the filtered particles were microbes based on the calibration data. (3) The probability threshold (defined by the user) step provides the probability of being microbes ranging from 0 to 100%. We demonstrate how Rapid-E+ identified simultaneously microbes based on the results of Bacillus subtilis (bacteria) and Penicillium chrysogenum (fungal spores). By using machine learning, Rapid-E+ achieved identification precision of 99% against the background. The further classification suggests the precision of 87% and 89% for Bacillus subtilis and Penicillium chrysogenum, respectively. The developed algorithm was subsequently used to evaluate the performance of microbe classification and quantification in real-time. The bacteria and fungi were aerosolized again in the chamber with different concentrations. Rapid-E+ can classify different types of microbes and then quantify them in real-time. Rapid-E+ enables classifying different types of microbes and quantifying them in real-time. Rapid-E+ can identify pollen down to species with similar or even better performance than the previous version (Rapid-E). Therefore, Rapid-E+ is an all-in-one instrument which classifies and quantifies not only pollen, but also bacteria and fungi. Based on the machine learning platform, the user can further develop proprietary algorithms for specific microbes (e.g., virus aerosols) and other aerosols (e.g., combustion-related particles that contain polycyclic aromatic hydrocarbons).

Keywords: bioaerosols, laser-induced fluorescence, Mie-scattering, microorganisms

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19671 Coupling Time-Domain Analysis for Dynamic Positioning during S-Lay Installation

Authors: Sun Li-Ping, Zhu Jian-Xun, Liu Sheng-Nan

Abstract:

In order to study the performance of dynamic positioning system during S-lay operations, dynamic positioning system is simulated with the hull-stinger-pipe coupling effect. The roller of stinger is simulated by the generalized elastic contact theory. The stinger is composed of Morrison members. Force on pipe is calculated by lumped mass method. Time domain of fully coupled barge model is analyzed combining with PID controller, Kalman filter and allocation of thrust using Sequential Quadratic Programming method. It is also analyzed that the effect of hull wave frequency motion on pipe-stinger coupling force and dynamic positioning system. Besides, it is studied that how S-lay operations affect the dynamic positioning accuracy. The simulation results are proved to be available by checking pipe stress with API criterion. The effect of heave and yaw motion cannot be ignored on hull-stinger-pipe coupling force and dynamic positioning system. It is important to decrease the barge’s pitch motion and lay pipe in head sea in order to improve safety of the S-lay installation and dynamic positioning.

Keywords: S-lay operation, dynamic positioning, coupling motion, time domain, allocation of thrust

Procedia PDF Downloads 449
19670 Extraction and Antibacterial Studies of Oil from Three Mango Kernel Obtained from Makurdi, Nigeria

Authors: K. Asemave, D. O. Abakpa, T. T. Ligom

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The ability of bacteria to develop resistance to many antibiotics cannot be undermined, given the multifaceted health challenges in the present times. For this reason, a lot of attention is on botanicals and their products in search of new antibacterial agents. On the other hand, mango kernel oils (MKO) can be heavily valorized by taking advantage of the myriads bioactive phytochemicals it contains. Herein, we validated the use of MKO as bioactive agent against bacteria. The MKOs for the study were extracted by soxhlet means with ethanol and hexane for 4 h from 3 different mango kernels, namely; 'local' (sample A), 'julie' (sample B), and 'john' (sample C). Prior to the extraction, ground fine particles of the kernels were obtained from the seed kernels dried in oven at 100 °C for 8 h. Hexane gave higher yield of the oils than ethanol. It was also qualitatively confirmed that the mango kernel oils contain some phytochemicals such as phenol, quinone, saponin, and terpenoid. The results of the antibacterial activities of the MKO against both gram positive (Staphylococcus aureus) and gram negative (Pseudomonas aeruginosa) at different concentrations showed that the oils extracted with ethanol gave better antibacterial properties than those of the hexane. More so, the bioactivities were best with the local mango kernel oil. Indeed this work has completely validated the previous claim that MKOs are effective antibacterial agents. Thus, these oils (especially the ethanol-derived ones) can be used as bacteriostatic and antibacterial agents in say food, cosmetics, and allied industries.

Keywords: bacteria, mango, kernel, oil, phytochemicals

Procedia PDF Downloads 140
19669 Regulation of Desaturation of Fatty Acid and Triglyceride Synthesis by Myostatin through Swine-Specific MEF2C/miR222/SCD5 Pathway

Authors: Wei Xiao, Gangzhi Cai, Xingliang Qin, Hongyan Ren, Zaidong Hua, Zhe Zhu, Hongwei Xiao, Ximin Zheng, Jie Yao, Yanzhen Bi

Abstract:

Myostatin (MSTN) is the master regulator of double muscling phenotype with overgrown muscle and decreased fatness in animals, but its action mode to regulate fat deposition remains to be elucidated. In this study a swin-specific pathway through which MSTN acts to regulate the fat deposition was deciphered. Deep sequenincing of the mRNA and miRNA of fat tissues of MSTN knockout (KO) and wildtype (WT) pigs discovered the positive correlation of myocyte enhancer factor 2C (MEF2C) and fat-inhibiting miR222 expression, and the inverse correlation of miR222 and stearoyl-CoA desaturase 5 (SCD5) expression. SCD5 is rodent-absent and expressed only in pig, sheep and cattle. Fatty acid spectrum of fat tissues revealed a lower percentage of oleoyl-CoA (18:1) and palmitoleyl CoA (16:1) in MSTN KO pigs, which are the catalyzing products of SCD5-mediated desaturation of steroyl CoA (18:0) and palmitoyl CoA (16:0). Blood metrics demonstrated a 45% decline of triglyceride (TG) content in MSTN KO pigs. In light of these observations we hypothesized that MSTN might act through MEF2C/miR222/SCD5 pathway to regulate desaturation of fatty acid as well as triglyceride synthesis in pigs. To this end, real-time PCR and Western blotting were carried out to detect the expression of the three genes stated above. These experiments showed that MEF2C expression was up-regulated by nearly 2-fold, miR222 up-regulated by nearly 3-fold and SCD5 down-regulated by nearly 50% in MSTN KO pigs. These data were consistent with the expression change in deep sequencing analysis. Dual luciferase reporter was then used to confirm the regulation of MEF2C upon the promoter of miR222. Ecotopic expression of MEF2C in preadipocyte cells enhanced miR222 expression by 3.48-fold. CHIP-PCR identified a putative binding site of MEF2C on -2077 to -2066 region of miR222 promoter. Electrophoretic mobility shift assay (EMSA) demonstrated the interaction of MEF2C and miR222 promoter in vitro. These data indicated that MEF2C transcriptionally regulates the expression of miR222. Next, the regulation of miR222 on SCD5 mRNA as well as its physiological consequences were examined. Dual luciferase reporter testing revealed the translational inhibition of miR222 upon the 3´ UTR (untranslated region) of SCD5 in preadipocyte cells. Transfection of miR222 mimics and inhibitors resulted in the down-regulation and up-regulation of SCD5 in preadipocyte cells respectively, consistent with the results from reporter testing. RNA interference of SCD5 in preadipocyte cells caused 26.2% reduction of TG, in agreement with the results of TG content in MSTN KO pigs. In summary, the results above supported the existence of a molecular pathway that MSTN signals through MEF2C/miR222/SCD5 to regulate the fat deposition in pigs. This swine-specific pathway offers potential molecular markers for the development and breeding of a new pig line with optimised fatty acid composition. This would benefit human health by decreasing the takeup of saturated fatty acid.

Keywords: fat deposition, MEF2C, miR222, myostatin, SCD5, pig

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19668 Antioxidant Responses and Malondialdehyde Levels in African Cat Fish (Clarias gariepinus) from Eleyele River in Nigeria

Authors: Oluwatosin Adetola Arojojoye, Olajumoke Olufunlayo Alao, Philip Odigili

Abstract:

This study investigated the extent of pollution in Eleyele River in Oyo State, Nigeria by investigating the antioxidant status and malondialdehyde levels (index of lipid peroxidation) in the organs of African Catfish, Clarias gariepinus from the river. Clarias gariepinus weighing between 250g-400g were collected from Eleyele River (a suspected polluted river) and Clarias gariepinus from a clean fish farm (Durantee fisheries) were used as the control. Levels of malondialdehyde, glutathione concentration (GSH) and activities of antioxidant enzymes - superoxide dismutase, catalase and glutathione-S-transferase (GST) were evaluated in the post-mitochondrial fractions of the liver, kidney and gills of the fishes. From the results, there were increases in malondialdehyde level and GSH concentration in the liver, kidney and gills of Clarias gariepinus from Eleyele River when compared with control. Glutathione-S-transferase activity was induced in the liver and kidney of Clarias gariepinus from Eleyele River when compared with control. However, the activity of this enzyme was depleted in the gills of fishes from Eleyele River compared with control. Also there was an induction in SOD activity in the liver of Clarias gariepinus from Eleyele River when compared with control but there was a decrease in the activity of this enzyme in the kidney and gills of fishes from Eleyele River compared with control. Increase in lipid peroxidation and alterations in antioxidant system in Clarias gariepinus from Eleyele River show that the fishes were under oxidative stress. These suggest that the river is polluted probably as a result of industrial, domestic and agricultural wastes frequently discharged into the river. This could pose serious health risks to consumers of water and aquatic organisms from the river.

Keywords: antioxidant, lipid peroxidation, Clarias gariepinus, Eleyele River

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19667 Effect of Change in Angle of Slope and Height of an Embankment on Safety Factor during Rapid Drawdown

Authors: Seyed Abolhassan Naeini, Azam Kouhpeyma

Abstract:

Reduction of water level at which a slope is submerged with it is called drawdown. Draw down can took place rapidly or slowly and in both situations, it can affect slope stability. Using coupled analysis (seepage and stability analysis) causes more accurate results. In this study, the stability of homogeneous embankment is investigated numerically. Slope safety factor changes due to changes in three factors of height, slope and drawdown rate have been investigated and compared. It was found that with increasing height and slope, the safety factor decreases, and with increasing the discharge rate, the safety factor increases.

Keywords: drawdown, slope stability, coupled seepage and stability analysis

Procedia PDF Downloads 108
19666 Effects of Electric Field on Diffusion Coefficients and Share Viscosity in Dusty Plasmas

Authors: Muhammad Asif ShakoorI, Maogang He, Aamir Shahzad

Abstract:

Dusty (complex) plasmas contained micro-sized charged dust particles in addition to ions, electrons, and neutrals. It is typically low-temperature plasma and exists in a wide variety of physical systems. In this work, the effects of an external electric field on the diffusion coefficient and share viscosity are investigated through equilibrium molecular dynamics (EMD) simulations in three-dimensional (3D) strongly coupled (SC) dusty plasmas (DPs). The effects of constant and varying normalized electric field strength (E*) have been computed along with different combinations of plasma states on the diffusion of dust particles using EMD simulations. Diffusion coefficient (D) and share viscosity (η) along with varied system sizes, in the limit of varying E* values, is accounted for an appropriate range of plasma coupling (Γ) and screening strength (κ) parameters. At varying E* values, it is revealed that the 3D diffusion coefficient increases with increasing E* and κ; however, it decreases with an increase of Γ but within statistical limits. The share viscosity increases with increasing E*and Γ and decreases with increasing κ. New simulation results are outstanding that the combined effects of electric field and screening strengths give well-matched values of Dandη at low-intermediate to large Γ with varying small-intermediate to large N. The current EMD simulation outcomes under varying electric field strengths are in satisfactory well-matched with previous known simulation data of EMD simulations of the SC-DPs. It has been shown that the present EMD simulation data enlarged the range of E* strength up to 0.1 ≤ E*≤ 1.0 in order to find the linear range of the DPs system and to demonstrate the fundamental nature of electric field linearity of 3D SC-DPs.

Keywords: strongly coupled dusty plasma, diffusion coefficient, share viscosity, molecular dynamics simulation, electric field strength

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19665 Influence of Long-Term Variability in Atmospheric Parameters on Ocean State over the Head Bay of Bengal

Authors: Anindita Patra, Prasad K. Bhaskaran

Abstract:

The atmosphere-ocean is a dynamically linked system that influences the exchange of energy, mass, and gas at the air-sea interface. The exchange of energy takes place in the form of sensible heat, latent heat, and momentum commonly referred to as fluxes along the atmosphere-ocean boundary. The large scale features such as El Nino and Southern Oscillation (ENSO) is a classic example on the interaction mechanism that occurs along the air-sea interface that deals with the inter-annual variability of the Earth’s Climate System. Most importantly the ocean and atmosphere as a coupled system acts in tandem thereby maintaining the energy balance of the climate system, a manifestation of the coupled air-sea interaction process. The present work is an attempt to understand the long-term variability in atmospheric parameters (from surface to upper levels) and investigate their role in influencing the surface ocean variables. More specifically the influence of atmospheric circulation and its variability influencing the mean Sea Level Pressure (SLP) has been explored. The study reports on a critical examination of both ocean-atmosphere parameters during a monsoon season over the head Bay of Bengal region. A trend analysis has been carried out for several atmospheric parameters such as the air temperature, geo-potential height, and omega (vertical velocity) for different vertical levels in the atmosphere (from surface to the troposphere) covering a period from 1992 to 2012. The Reanalysis 2 dataset from the National Centers for Environmental Prediction-Department of Energy (NCEP-DOE) was used in this study. The study signifies that the variability in air temperature and omega corroborates with the variation noticed in geo-potential height. Further, the study advocates that for the lower atmosphere the geo-potential heights depict a typical east-west contrast exhibiting a zonal dipole behavior over the study domain. In addition, the study clearly brings to light that the variations over different levels in the atmosphere plays a pivotal role in supporting the observed dipole pattern as clearly evidenced from the trends in SLP, associated surface wind speed and significant wave height over the study domain.

Keywords: air temperature, geopotential height, head Bay of Bengal, long-term variability, NCEP reanalysis 2, omega, wind-waves

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19664 Study of Nitrogen Species Fate and Transport in Subsurface: To Assess the Impact of Wastewater Irrigation

Authors: C. Mekala, Indumathi M. Nambi

Abstract:

Nitrogen pollution in groundwater arising from wastewater and fertilizer application through vadose zone is a major problem and it causes a prime risk to groundwater based drinking water supplies. Nitrogenous compounds namely ammonium, nitrate and nitrite fate and transport in soil subsurface were studied experimentally. The major process like sorption, leaching, biotransformation involving microbial growth kinetics, and biological clogging due to biomass growth were assessed and modeled with advection-dispersion reaction equations for ammonium, nitrate and acetate in a saturated, heterogeneous soil medium. The transport process was coupled with freundlich sorption and monod inhibition kinetics for immobile bacteria and permeability reduction due to biomass growth will be verified and validated with the numerical model. This proposed mathematical model will be very helpful in the development of a management model for a sustainable and safe wastewater reuse strategies such as irrigation and groundwater recharge.

Keywords: nitrogen species transport, transformation, biological clogging, biokinetic parameters, contaminant transport model, saturated soil

Procedia PDF Downloads 391
19663 Angiotensin Converting Enzyme (ACE) and Angiotensinogen (AGT) Gene Variants in Pakistani Patients of Diabetes Mellitus and Diabetic Nephropathy

Authors: Rozeena Shaikh, Syed M Shahid, Jamil Ahmad, Qaisar Mansoor, Muhammad Ismail, Abid Azhar

Abstract:

Introduction: Diabetes mellitus (DM) is a prevalent non-communicable disease worldwide. In most high-income countries as well as middle-income and low- income countries. DM is among the top causes of deaths. DM may lead to many vascular complications like hypertension, nephropathy, retinopathy, neuropathy, and foot. Diabetic nephropathy (DN) characterized by persistent albuminuria is a leading cause of end stage renal failure (ESRF). Pathogenesis of diabetic nephropathy is implicated by the polymorphisms in genes encoding the components of reninangiotensin- aldosteron system (RAAS) which include angiotensinogen (AGT), angiotensin-II receptor and particularly angiotensin converting enzyme (ACE) gene. Method: Study subjects include 110 control, 110 patients with DM without hypertension, 110 patients with DM with hypertension and 110 patients with DN. Blood samples were collected for Biochemical analysis and PCR and sequencing for the specific region of both genes. Results: The frequency of DD genotype and D allele of ACE (I/D) was significantly (p<0.05) high in DM normotensive, DM hypertensive and DN patients when compared to control. The ACE G2350A genotypes and allele frequencies were significantly different (p<0.05) in DM hypertensive patients as compared to control and DN, while no difference was observed between DM normotensive and DN when compared to control. The genotypes and alleles of AGT (M268T) polymorphism were significantly different (p<0.05) in DM normotensive, DM hypertensive and DN when compared to control. Conclusion: The DD genotype and D allele of ACE (I/D), GG genotype and G allele of ACE (G2350A) and the TT genotype and T allele of AGT (M268T) polymorphism have shown a significant difference in genotype and allele frequencies between controls and patients.

Keywords: genetic variations, ACE, AGT, diabetes mellitus, diabetic nephropathy, Pakistan

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19662 Formulation and in Vitro Characterization of Bioactives Loaded Polymeric Nanoparticle Incorporated into Multiphase Hydrogel System for the Treatment of Infected Burn Wound

Authors: Rajni Kant Panik, Deependra Singh, Manju Singh

Abstract:

Despite significant advances in the treatment of severe burn injury, infection and sepsis persist as frequent causes of morbidity and mortality for burn victims due to extensive compromise of the skin and contiguous tissue that serve as a protective barrier against microbial invasion. In the setting of a burn wound infection, Staphylococcus aureus is the most commonly isolated pathogens from bloodstream infections in burn care hospitals. We aimed to develop a biocompatible system of Poly vinyl alcohol (PVA)-sodium alginate hydrogel carrying multiple drugs- catalase and mupirocin in controlled manner for effective and complete burn wound healing. PLGA nanoparticles of Catalase and mupirocin were prepared by homogenization method and optimized system was incorporated in PVA-sodium alginate slurry. PVA-sodium alginate hydrogels were prepared by freeze thaw method. The prepared dispersion was casted into films to prepare multiphase hydrogel system and characterized by in vitro and in vivo studies. The study clearly showed the beneficial effect of antioxidant enzyme and antibiotic in the treatment of infected burn wound, as evidenced by the reduced incidence of wound infection and the shortening of healing time.

Keywords: burn wound, catalase, mupirocin, wound healing

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19661 Growth Performance and Meat Quality of Cobb 500 Broilers Fed Phytase and Tannase Treated Sorghum-Based Diets

Authors: Magaya Rutendo P., Mutibvu Tonderai, Nyahangare emmanuel T., Ncube Sharai

Abstract:

This study aimed to evaluate the effects of phytase and tannase addition in broiler diets on growth performance and meat quality of broilers fed sorghum-based diets. Twelve experimental diets were formulated at three sorghum levels, which include 0, 50, and 100%, and 4 enzyme levels: No enzyme, 5000FTU phytase, 25TU tannase, and a combination of 5000FTU phytase plus 25TU tannase. Data on voluntary feed intake, average weekly weight gain and feed conversion ratio were recorded and used to assess growth performance. Meat technical and nutritional parameters were used to determine meat quality. Broilers fed total sorghum diets with phytase and tannase enzyme combination had the highest feed intake in the first (24.4 ± 0.04g/bird/day) and second weeks of life (23.0 ± 1.06g/bird/day), respectively. Complete sorghum diets with phytase (83.0 ± 0.88g/bird/day) and tannase (122.0 ± 0.88g/bird/day) showed the highest feed intake in the third and fourth weeks, respectively. Broilers fed 50% sorghum diets with tannase (135.3 ± 0.05g/bird/day) and complete maize diets with phytase (158.1 ± 0.88g/bird/day) had the highest feed intake during weeks five and six, respectively. Broilers fed a 50% sorghum diet without enzymes had the highest weight gain in the final week (606.5 ± 32.39g). Comparable feed conversion was observed in birds fed complete maize and 50% sorghum diets. Dietary treatment significantly influences the live body, carcass, liver, kidneys, abdominal fat pad weight, and intestinal length. However, it did not affect Pectoralis major meat nutritional and technical parameters.

Keywords: feed efficiency, sorghum, carcass, exogenous enzymes

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19660 Effects of Bile Acids and Lipase Supplementation in Low-Energy Diets on Growth Performance and Meat Quality in Broiler Chickens

Authors: Muhammad Adeel Arshad, Shaukat Ali Bhatti

Abstract:

The study aimed to investigate the effect of bile acids and lipase supplementation in low-energy diets on growth performance and meat quality of broilers. Seven hundred day-old Cobb-500 broiler chicks with an average initial body weight of 45.9 ± 0.3 g were assigned to 5 dietary treatments, with five replications of 28 birds each in a completely randomized design. The five treatments were as follows: (i) HE: broilers received a diet with high energy content; (ii) LE: broilers received a diet with low energy content and energy content reduced by 100 kcal/kg as compared to HE; (iii) LEB: broilers received a diet similar to the LE group supplemented with 300 g/ton bile acids; (iv) LEL: broilers received a diet similar to the LE group supplemented with 180 g/ton lipase enzyme and (v) LEBL: broilers received a diet similar to the LE group supplemented with both 300 g/ton bile acids and 180 g/ton lipase enzyme. The experimental period lasted for 35 days. Broilers fed HE had a lower (P < 0.05) body weight (BW) gain and lower feed intake (1-35 d), but during finisher period (21-35 d), BW gain was similar with other treatments. Feed conversion ratio (FCR) was lower in HE and higher in LEBL group (P < 0.05), while the LE, LEB, and LEL had intermediate values. At 35 d no difference occurred between treatment for water holding capacity and pH of breast and thigh muscles (P > 0.05). The relative weight of pancreas was higher (P < 0.05) in LEB treatment but lower (P < 0.05) in LEL treatment. In conclusion, bile acids and lipase supplementation at 300 g/ton and 150g/ton of feed in low-energy diets respectively had no effect on broiler performance and meat quality. However, FCR was improved in HE treatment.

Keywords: bile acids, energy, enzyme, growth

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19659 A Two-Phase Flow Interface Tracking Algorithm Using a Fully Coupled Pressure-Based Finite Volume Method

Authors: Shidvash Vakilipour, Scott Ormiston, Masoud Mohammadi, Rouzbeh Riazi, Kimia Amiri, Sahar Barati

Abstract:

Two-phase and multi-phase flows are common flow types in fluid mechanics engineering. Among the basic and applied problems of these flow types, two-phase parallel flow is the one that two immiscible fluids flow in the vicinity of each other. In this type of flow, fluid properties (e.g. density, viscosity, and temperature) are different at the two sides of the interface of the two fluids. The most challenging part of the numerical simulation of two-phase flow is to determine the location of interface accurately. In the present work, a coupled interface tracking algorithm is developed based on Arbitrary Lagrangian-Eulerian (ALE) approach using a cell-centered, pressure-based, coupled solver. To validate this algorithm, an analytical solution for fully developed two-phase flow in presence of gravity is derived, and then, the results of the numerical simulation of this flow are compared with analytical solution at various flow conditions. The results of the simulations show good accuracy of the algorithm despite using a nearly coarse and uniform grid. Temporal variations of interface profile toward the steady-state solution show that a greater difference between fluids properties (especially dynamic viscosity) will result in larger traveling waves. Gravity effect studies also show that favorable gravity will result in a reduction of heavier fluid thickness and adverse gravity leads to increasing it with respect to the zero gravity condition. However, the magnitude of variation in favorable gravity is much more than adverse gravity.

Keywords: coupled solver, gravitational force, interface tracking, Reynolds number to Froude number, two-phase flow

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19658 Numerical Investigation of Multiphase Flow in Pipelines

Authors: Gozel Judakova, Markus Bause

Abstract:

We present and analyze reliable numerical techniques for simulating complex flow and transport phenomena related to natural gas transportation in pipelines. Such kind of problems are of high interest in the field of petroleum and environmental engineering. Modeling and understanding natural gas flow and transformation processes during transportation is important for the sake of physical realism and the design and operation of pipeline systems. In our approach a two fluid flow model based on a system of coupled hyperbolic conservation laws is considered for describing natural gas flow undergoing hydratization. The accurate numerical approximation of two-phase gas flow remains subject of strong interest in the scientific community. Such hyperbolic problems are characterized by solutions with steep gradients or discontinuities, and their approximation by standard finite element techniques typically gives rise to spurious oscillations and numerical artefacts. Recently, stabilized and discontinuous Galerkin finite element techniques have attracted researchers’ interest. They are highly adapted to the hyperbolic nature of our two-phase flow model. In the presentation a streamline upwind Petrov-Galerkin approach and a discontinuous Galerkin finite element method for the numerical approximation of our flow model of two coupled systems of Euler equations are presented. Then the efficiency and reliability of stabilized continuous and discontinous finite element methods for the approximation is carefully analyzed and the potential of the either classes of numerical schemes is investigated. In particular, standard benchmark problems of two-phase flow like the shock tube problem are used for the comparative numerical study.

Keywords: discontinuous Galerkin method, Euler system, inviscid two-fluid model, streamline upwind Petrov-Galerkin method, twophase flow

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19657 Assessment of Microbiological Status of Branded and Street Vended Ice-Cream Offered for Public Consumption: A Comparative Study in Tangail Municipality, Bangladesh

Authors: Afroza Khatun, Masuma, Md. Younus Mia, Kamal Kanta Das

Abstract:

Analysis of the microbial status and physicochemical parameters of some branded and street vended ice cream showed that total viable bacteria in branded ice cream ranged from 4.8×10³ to 1.10×10⁵ cfu/ml, and in street vended ice-cream ranged from 7.5×10⁴ to 1.6×10⁸ cfu/ml. Total coliform bacteria present up to 9.20×10³ cfu/ml in branded ice cream and 5.3×10³ to 9.6×10⁶ cfu/ml observed in street vended ice cream. Total E. coli were found to be present within a range from 0 to 4.5×10³ cfu/ml in branded and 4.1×10² to 7.5×10⁴ cfu/ml in street ice cream. The ranges of Staphylococcus aureus count were 1.8×10² to 2.9×10⁴ cfu/ml (branded) and 3.9×10⁴ to 7.9×10⁶ cfu/ml (street). The pH of both types of ice cream showed acidic to neutral conditions where the concentration of pH for branded ice cream was 5.5 to 6.9, as well as the value of pH in street ice cream, was 6.2 to 7.0. The range of Total soluble solids in several branded ice creams was 26 to 29%, and the value of TSS obtained in street-vended ice-creams ranged from 5 to 10%. The overall results of this research demonstrated that the microbial quality in all street ice creams exceeded the BSTI standard and exhibited lower quality than the industrially produced branded ice creams due to comparatively faulty manufacturing processes and poor hygiene practices. The presence of pathogenic microbes was also observed in branded ice creams which was quite alarming for public health. So it is suggested that the government authorized organization should conduct the proper monitoring system to ensure that both branded and street vended ice-creams are microbiologically safe to prevent public health hazards.

Keywords: food safety, microbiological analysis, physicochemical, ice-cream, E. coli, Staphylococcus aureus

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19656 Bacterial Recovery of Copper Ores

Authors: Zh. Karaulova, D. Baizhigitov

Abstract:

At the Aktogay deposit, the oxidized ore section has been developed since 2015; by now, the reserves of easily enriched ore are decreasing, and a large number of copper-poor, difficult-to-enrich ores has been accumulated in the dumps of the KAZ Minerals Aktogay deposit, which is unprofitable to mine using the traditional mining methods. Hence, another technology needs to be implemented, which will significantly expand the raw material base of copper production in Kazakhstan and ensure the efficient use of natural resources. Heap and dump bacterial recovery are the most acceptable technologies for processing low-grade secondary copper sulfide ores. Test objects were the copper ores of Aktogay deposit and chemolithotrophic bacteria Leptospirillum ferrooxidans (L.f.), Acidithiobacillus caldus (A.c.), Sulfobacillus Acidophilus (S.a.), which are mixed cultures were both used in bacterial oxidation systems. They can stay active in the 20-400C temperature range. These bacteria were the most extensively studied and widely used in sulfide mineral recovery technology. Biocatalytic acceleration was achieved as a result of bacteria oxidizing iron sulfides to form iron sulfate, which subsequently underwent chemical oxidation to become sulfate oxide. The following results have been achieved at the initial stage: the goal was to grow and maintain the life activity of bacterial cultures under laboratory conditions. These bacteria grew the best within the pH 1,2-1,8 range with light stirring and in an aerated environment. The optimal growth temperature was 30-33оC. The growth rate decreased by one-half for each 4-5°C fall in temperature from 30°C. At best, the number of bacteria doubled every 24 hours. Typically, the maximum concentration of cells that can be grown in ferrous solution is about 107/ml. A further step researched in this case was the adaptation of microorganisms to the environment of certain metals. This was followed by mass production of inoculum and maintenance for their further cultivation on a factory scale. This was done by adding sulfide concentrate, allowing the bacteria to convert the ferrous sulfate as indicated by the Eh (>600 mV), then diluting to double the volume and adding concentrate to achieve the same metal level. This process was repeated until the desired metal level and volumes were achieved. The final stage of bacterial recovery was the transportation and irrigation of secondary sulfide copper ores of the oxidized ore section. In conclusion, the project was implemented at the Aktogay mine since the bioleaching process was prolonged. Besides, the method of bacterial recovery might compete well with existing non-biological methods of extraction of metals from ores.

Keywords: bacterial recovery, copper ore, bioleaching, bacterial inoculum

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19655 Enhanced Production of Endo-β-1,4-Xylanase from a Newly Isolated Thermophile Geobacillus stearothermophilus KIBGE-IB29 for Prospective Industrial Applications

Authors: Zainab Bibi, Afsheen Aman, Shah Ali Ul Qader

Abstract:

Endo-β-1,4-xylanases [EC 3.2.1.8] are one of the major groups of enzymes that are involved in degradation process of xylan and have several applications in food, textile and paper processing industries. Due to broad utility of endo-β-1,4-xylanase, researchers are focusing to increase the productivity of this hydrolase from various microbial species. Harsh industrial condition, faster reaction rate and efficient hydrolysis of xylan with low risk of contamination are critical requirements of industry that can be fulfilled by synthesizing the enzyme with efficient properties. In the current study, a newly isolated thermophile Geobacillus stearothermophilus KIBGE-IB29 was used in order to attain the maximum production of endo-1,4-β-xylanase. Bacterial culture was isolated from soil, collected around the blast furnace site of a steel processing mill, Karachi. Optimization of various nutritional and physical factors resulted the maximum synthesis of endo-1,4-β-xylanase from a thermophile. High production yield was achieved at 60°C and pH-6.0 after 24 hours of incubation period. Various nitrogen sources viz. peptone, yeast extract and meat extract improved the enzyme synthesis with 0.5%, 0.2% and 0.1% optimum concentrations. Dipotassium hydrogen phosphate (0.25%), potassium dihydrogen phosphate (0.05%), ammonium sulfate (0.05%) and calcium chloride (0.01%) were noticed as valuable salts to improve the production of enzyme. The thermophilic nature of isolate, with its broad pH stability profile and reduced fermentation time indicates its importance for effective xylan saccharification and for large scale production of endo-1,4-β-xylanase.

Keywords: geobacillus, optimization, production, xylanase

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19654 Numerical Solution to Coupled Heat and Moisture Diffusion in Bio-Sourced Composite Materials

Authors: Mnasri Faiza, El Ganaoui Mohammed, Khelifa Mourad, Gabsi Slimane

Abstract:

The main objective of this paper is to describe the hydrothermal behavior through porous material of construction due to temperature gradient. The construction proposed a bi-layer structure which composed of two different materials. The first is a bio-sourced panel named IBS-AKU (inertia system building), the second is the Neopor material. This system (IBS-AKU Neopor) is developed by a Belgium company (Isohabitat). The study suggests a multi-layer structure of the IBS-AKU panel in one dimension. A numerical method was proposed afterwards, by using the finite element method and a refined mesh area to strong gradients. The evolution of temperature fields and the moisture content has been processed.

Keywords: heat transfer, moisture diffusion, porous media, composite IBS-AKU, simulation

Procedia PDF Downloads 495
19653 Computational Aerodynamic Shape Optimisation Using a Concept of Control Nodes and Modified Cuckoo Search

Authors: D. S. Naumann, B. J. Evans, O. Hassan

Abstract:

This paper outlines the development of an automated aerodynamic optimisation algorithm using a novel method of parameterising a computational mesh by employing user–defined control nodes. The shape boundary movement is coupled to the movement of the novel concept of the control nodes via a quasi-1D-linear deformation. Additionally, a second order smoothing step has been integrated to act on the boundary during the mesh movement based on the change in its second derivative. This allows for both linear and non-linear shape transformations dependent on the preference of the user. The domain mesh movement is then coupled to the shape boundary movement via a Delaunay graph mapping. A Modified Cuckoo Search (MCS) algorithm is used for optimisation within the prescribed design space defined by the allowed range of control node displacement. A finite volume compressible NavierStokes solver is used for aerodynamic modelling to predict aerodynamic design fitness. The resulting coupled algorithm is applied to a range of test cases in two dimensions including the design of a subsonic, transonic and supersonic intake and the optimisation approach is compared with more conventional optimisation strategies. Ultimately, the algorithm is tested on a three dimensional wing optimisation case.

Keywords: mesh movement, aerodynamic shape optimization, cuckoo search, shape parameterisation

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19652 Rechargable N-Halamine Nanoparticles for Antibacterial and Antifouling Applications

Authors: Michal Natan, Ori Gutman, Shlomo Margel, Ehud Banin

Abstract:

Biofilm formation is a serious problem in medical and industrial settings due to the increased resistance of these communities to killing compared to free-living bacteria. This has prompted the search for agents that can inhibit both bacterial growth and biofilm formation. In this study, N-halamine rechargeable nanoparticles (NPs) were synthesized by co-polymerization of the monomer methacryl amide and the cross-linker monomer N,N-methylene bisacryl amide, and were subsequently loaded with Cl+, using bleach. The chlorinated NPs exhibited remarkable stability to organic reagents. The antibacterial mechanism of the P(MAA-MBAA)-Cl NPs involved generation of reactive oxygen species (ROS) only upon exposure to organic media, but not upon incubation in water, suggesting a specific activation. Moreover, a unique interaction of the P(MAA-MBAA)-Cl NPs with Staphylococcus aureus bacteria but not with human cells was discovered, whereby these microorganisms were all specifically targeted and marked for destruction. Finally, in collaboration with Netafim Ltd. irrigation drippers containing the P(MAA-MBAA)-Cl were incubated in the field and were shown to prevent fouling on them for 5 months as opposed to the control drippers that exhibited substantial fouling. Further, the NPs offer recharging to the surface, thus providing long-lasting protection that does not exist in the products available today. Taken together, the results demonstrate the great potential of implementing the charged NPs in devices and surfaces to prevent bacterial growth.

Keywords: bacteria, biofilm, fouling, nanoparticles

Procedia PDF Downloads 188
19651 Role of Fish Hepatic Aldehyde Oxidase in Oxidative In Vitro Metabolism of Phenanthridine Heterocyclic Aromatic Compound

Authors: Khaled S. Al Salhen

Abstract:

Aldehyde oxidase is molybdo-flavoenzyme involved in the oxidation of hundreds of endogenous and exogenous and N-heterocyclic compounds and environmental pollutants. Uncharged N-heterocyclic aromatic compounds such phenanthridine are commonly distributed pollutants in soil, air, sediments, surface water and groundwater, and in animal and plant tissues. Phenanthridine as uncharged N-heterocyclic aromatic compound was incubated with partially purified aldehyde oxidase from rainbow trout fish liver. Reversed-phase HLPC method was used to separate the oxidation products from phenanthridine and the metabolite was identified. The 6(5H)-phenanthridinone was identified the major metabolite by partially purified aldehyde oxidase from fish liver. Kinetic constant for the oxidation reactions were determined spectrophotometrically and showed that this substrate has a good affinity (Km = 78 ± 7.6 µM) for hepatic aldehyde oxidase, coupled with a relatively high oxidation rate (0.77± 0.03 nmol/min/mg protein). In addition, the kinetic parameters of hepatic fish aldehyde oxidase towards the phenanthridine substrate indicate that in vitro biotransformation by hepatic fish aldehyde oxidase will be a significant pathway. This study confirms that partially purified aldehyde oxidase from fish liver is indeed the enzyme responsible for the in vitro production 6(5H)-phenanthridinone metabolite as it is a major metabolite by mammalian aldehyde oxidase.

Keywords: aldehyde oxidase, fish, phenanthridine, specificity

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19650 Antidiabetic Effect of Methanolic Leaves Extract and Isolated Constituents from Saraca Asoca

Authors: Sunil Kumar

Abstract:

Background: The present study was performed to investigate the antidiabetic effect of the constituents isolated from Sarca asoca by enzyme inhibitory activity. Methods: The dried leaves of Sarca asoca were defatted with petroleum ether and further the same amount plant materials were extracted with methanol. The dried methanol extract was subjected to fractionation and chromatographic separation, which led to the isolation of kaemferol, β-sitosterol and quercetin stigmasterol. Their structures were elucidated on the basis of spectroscopic studies as well as by comparison with the data available in the literature. The compounds were evaluated for in vitro enzyme inhibition effect. Results: The isolated compounds kaemferol, β-sitosterol and stigmasterol showed 45.32, 40.5 and 41.23% α-amylase inhibition respectively and 43.45, 39.29 and 32.43% α-glucosidase inhibition respectively at the conc. of 50 µg/kg. Conclusion: The compounds isolated from Sarca asoca showed in vitro and in vivo antidiabetic activity. So, Euphorbia hirta is a beneficial plant for management of diabetic disorders.

Keywords: diabetes, quercetin, sitosterol, stigmasterol

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19649 Changes of pH and Pseudomonas Aeruginosa Growth in Liquid Media

Authors: Sayaka Ono, Ryutaro Imai, Tomoko Ehara, Tetsuya Matsumoto, Hajime Matsumura

Abstract:

Background: Wound pH affects a number of important factors in wound healing. We previously measured the pH value of the exudates collected from second-degree burns and found that the increase in pH was observed in the burn wounds in which colonized by Staphylococcus spp., and the increase in pH was evident prior to the clinical findings of local infection. To investigate the relationship between the changes of pH value and bacterial growth, we performed in vitro study using Pseudomonas aeruginosa and liquid medium as a locally infected wound equivalent model. Methods: Pseudomonas aeruginosa standard strain (ATCCR 10145TM) was cultured at 37 °C environment in Luria Broth Miller medium. The absorbance rate which means the amount of bacteria was measured by a microplate reader 2300EnSpireTM). The pH was measured using pH-indicator strips (MColorpHastTM). The statistical analysis was performed using the product-moment correlation coefficient of Pearson's. Results: The absorbance rate and pH value were increased along with culture period. There was a positive correlation between pH value and absorbance rate (n = 27, Pearson's r = 0.985). Moreover, there was a positive correlation between pH value and the culture period (n = 18, Pearson's r = 0.901). The bacteria was well growth in the media from pH 6.6 to pH 8.0 and the pH of culture media converged at 8 -9 along with the bacterial growth. Conclusion: From these results, we conclude that pH value of the wound is correlated with the number of viable bacteria and bacterial growth periods.

Keywords: colonization, potential of hydrogen, Pseudomonas aeruginosa, wound

Procedia PDF Downloads 261
19648 Cluster-Based Exploration of System Readiness Levels: Mathematical Properties of Interfaces

Authors: Justin Fu, Thomas Mazzuchi, Shahram Sarkani

Abstract:

A key factor in technological immaturity in defense weapons acquisition is lack of understanding critical integrations at the subsystem and component level. To address this shortfall, recent research in integration readiness level (IRL) combines with technology readiness level (TRL) to form a system readiness level (SRL). SRL can be enriched with more robust quantitative methods to provide the program manager a useful tool prior to committing to major weapons acquisition programs. This research harnesses previous mathematical models based on graph theory, Petri nets, and tropical algebra and proposes a modification of the desirable SRL mathematical properties such that a tightly integrated (multitude of interfaces) subsystem can display a lower SRL than an inherently less coupled subsystem. The synthesis of these methods informs an improved decision tool for the program manager to commit to expensive technology development. This research ties the separately developed manufacturing readiness level (MRL) into the network representation of the system and addresses shortfalls in previous frameworks, including the lack of integration weighting and the over-importance of a single extremely immature component. Tropical algebra (based on the minimum of a set of TRLs or IRLs) allows one low IRL or TRL value to diminish the SRL of the entire system, which may not be reflective of actuality if that component is not critical or tightly coupled. Integration connections can be weighted according to importance and readiness levels are modified to be a cardinal scale (based on an analytic hierarchy process). Integration arcs’ importance are dependent on the connected nodes and the additional integrations arcs connected to those nodes. Lack of integration is not represented by zero, but by a perfect integration maturity value. Naturally, the importance (or weight) of such an arc would be zero. To further explore the impact of grouping subsystems, a multi-objective genetic algorithm is then used to find various clusters or communities that can be optimized for the most representative subsystem SRL. This novel calculation is then benchmarked through simulation and using past defense acquisition program data, focusing on the newly introduced Middle Tier of Acquisition (rapidly field prototypes). The model remains a relatively simple, accessible tool, but at higher fidelity and validated with past data for the program manager to decide major defense acquisition program milestones.

Keywords: readiness, maturity, system, integration

Procedia PDF Downloads 73
19647 Selective Immobilization of Fructosyltransferase onto Glutaraldehyde Modified Support and Its Application in the Production of Fructo-Oligosaccharides

Authors: Milica B. Veljković, Milica B. Simović, Marija M. Ćorović, Ana D. Milivojević, Anja I. Petrov, Katarina M. Banjanac, Dejan I. Bezbradica

Abstract:

In recent decades, the scientific community has recognized the growing importance of prebiotics, and therefore, numerous studies are focused on their economic production due to their low presence in natural resources. It has been confirmed that prebiotics is a source of energy for probiotics in the gastrointestinal tract (GIT) and enable their proliferation, consequently leading to the normal functioning of the intestinal microbiota. Also, products of their fermentation are short-chain fatty acids (SCFA), which play a key role in maintaining and improving the health not only of the GIT but also of the whole organism. Among several confirmed prebiotics, fructooligosaccharides (FOS) are considered interesting candidates for use in a wide range of products in the food industry. They are characterized as low-calorie and non-cariogenic substances that represent an adequate sugar substitute and can be considered suitable for use in products intended for diabetics. The subject of this research will be the production of FOS by transforming sucrose using a fructosyltransferase (FTase) present in commercial preparation Pectinex® Ultra SP-L, with special emphasis on the development of adequate FTase immobilization method that would enable selective isolation of the enzyme responsible for the synthesis of FOS from the complex enzymatic mixture. This would lead to considerable enzyme purification and allow its direct incorporation into different sucrose-based products without the fear that the action of the other hydrolytic enzymes may adversely affect the products' functional characteristics. Accordingly, the possibility of selective immobilization of the enzyme using support with primary amino groups, Purolite® A109, which was previously activated and modified using glutaraldehyde (GA), was investigated. In the initial phase of the research, the effects of individual immobilization parameters such as pH, enzyme concentration, and immobilization time were investigated to optimize the process using support chemically activated with 15% and 0.5% GA to form dimers and monomers, respectively. It was determined that highly active immobilized preparations (371.8 IU/g of support - dimer and 213.8 IU/g of support – monomer) were achieved under acidic conditions (pH 4) provided that an enzyme concentration was 50 mg/g of support after 7 h and 3 h, respectively. Bearing in mind the obtained results of the expressed activity, it is noticeable that the formation of dimers showed higher reactivity compared to the form of monomers. Also, in the case of support modification using 15% GA, the value of the ratio of FTase and pectinase (as dominant enzyme mixture component) activity immobilization yields was 16.45, indicating the high feasibility of selective immobilization of FTase on modified polystyrene resin. After obtaining immobilized preparations of satisfactory features, they were tested in a reaction of FOS synthesis under determined optimal conditions. The maximum FOS yields of approximately 50% of total carbohydrates in the reaction mixture were recorded after 21 h. Finally, it can be concluded that the examined immobilization method yielded highly active, stable and, more importantly, refined enzyme preparation that can be further utilized on a larger scale for the development of continual processes for FOS synthesis, as well as for modification of different sucrose-based mediums.

Keywords: chemical modification, fructooligosaccharides, glutaraldehyde, immobilization of fructosyltransferase

Procedia PDF Downloads 171