Search results for: carriers of active substances
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4337

Search results for: carriers of active substances

3497 Refinement of Existing Benzthiazole lead Targeting Lysine Aminotransferase in Dormant Stage of Mycobacterium tuberculosis

Authors: R. Reshma srilakshmi, S. Shalini, P. Yogeeswari, D. Sriram

Abstract:

Lysine aminotransferase is a crucial enzyme for dormancy in M. tuberculosis. It is involved in persistence and antibiotic resistance. In present work, we attempted to develop benzthiazole derivatives as lysine aminotransferase inhibitors. In our attempts, we also unexpectedly arrived at an interesting compound 21 (E)-4-(5-(2-(benzo[d]thiazol-2-yl)-2-cyanovinyl)thiophen-2-yl)benzoic acid which even though has moderate activity against persistent phase of mycobacterium, it has significant potency against active phase. In the entire series compound 22 (E)-4-(5-(2-(benzo[d]thiazol-2-yl)-2-cyanovinyl)thiophen-2-yl)isophthalic acid emerged as potent molecule with LAT IC50 of 2.62 µM. It has a significant log reduction of 2.9 and 2.3 fold against nutrient starved and biofilm forming mycobacteria. It was found to be inactive in MABA assay and M.marinum induced zebra fish model. It is also devoid of cytotoxicity. Compound 22 was also found to possess bactericidal effect which is independent of concentration and time. It was found to be effective in combination with Rifampicin in 3D granuloma model. The results are very encouraging as the hit molecule shows activity against active as well as persistent forms of tuberculosis. The identified hit needs further more pharmacokinetic and dynamic screening for development as new drug candidate.

Keywords: benzothiazole, latent tuberculosis, LAT, nutrient starvation

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3496 Optimizing Logistics for Courier Organizations with Considerations of Congestions and Pickups: A Courier Delivery System in Amman as Case Study

Authors: Nader A. Al Theeb, Zaid Abu Manneh, Ibrahim Al-Qadi

Abstract:

Traveling salesman problem (TSP) is a combinatorial integer optimization problem that asks "What is the optimal route for a vehicle to traverse in order to deliver requests to a given set of customers?”. It is widely used by the package carrier companies’ distribution centers. The main goal of applying the TSP in courier organizations is to minimize the time that it takes for the courier in each trip to deliver or pick up the shipments during a day. In this article, an optimization model is constructed to create a new TSP variant to optimize the routing in a courier organization with a consideration of congestion in Amman, the capital of Jordan. Real data were collected by different methods and analyzed. Then, concert technology - CPLEX was used to solve the proposed model for some random generated data instances and for the real collected data. At the end, results have shown a great improvement in time compared with the current trip times, and an economic study was conducted afterwards to figure out the impact of using such models.

Keywords: travel salesman problem, congestions, pick-up, integer programming, package carriers, service engineering

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3495 Control Flow around NACA 4415 Airfoil Using Slot and Injection

Authors: Imine Zakaria, Meftah Sidi Mohamed El Amine

Abstract:

One of the most vital aerodynamic organs of a flying machine is the wing, which allows it to fly in the air efficiently. The flow around the wing is very sensitive to changes in the angle of attack. Beyond a value, there is a phenomenon of the boundary layer separation on the upper surface, which causes instability and total degradation of aerodynamic performance called a stall. However, controlling flow around an airfoil has become a researcher concern in the aeronautics field. There are two techniques for controlling flow around a wing to improve its aerodynamic performance: passive and active controls. Blowing and suction are among the active techniques that control the boundary layer separation around an airfoil. Their objective is to give energy to the air particles in the boundary layer separation zones and to create vortex structures that will homogenize the velocity near the wall and allow control. Blowing and suction have long been used as flow control actuators around obstacles. In 1904 Prandtl applied a permanent blowing to a cylinder to delay the boundary layer separation. In the present study, several numerical investigations have been developed to predict a turbulent flow around an aerodynamic profile. CFD code was used for several angles of attack in order to validate the present work with that of the literature in the case of a clean profile. The variation of the lift coefficient CL with the momentum coefficient

Keywords: CFD, control flow, lift, slot

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3494 Combined Influence of Charge Carrier Density and Temperature on Open-Circuit Voltage in Bulk Heterojunction Organic Solar Cells

Authors: Douglas Yeboah, Monishka Narayan, Jai Singh

Abstract:

One of the key parameters in determining the power conversion efficiency (PCE) of organic solar cells (OSCs) is the open-circuit voltage, however, it is still not well understood. In order to examine the performance of OSCs, it is necessary to understand the losses associated with the open-circuit voltage and how best it can be improved. Here, an analytical expression for the open-circuit voltage of bulk heterojunction (BHJ) OSCs is derived from the charge carrier densities without considering the drift-diffusion current. The open-circuit voltage thus obtained is dependent on the donor-acceptor band gap, the energy difference between the highest occupied molecular orbital (HOMO) and the hole quasi-Fermi level of the donor material, temperature, the carrier density (electrons), the generation rate of free charge carriers and the bimolecular recombination coefficient. It is found that open-circuit voltage increases when the carrier density increases and when the temperature decreases. The calculated results are discussed in view of experimental results and agree with them reasonably well. Overall, this work proposes an alternative pathway for improving the open-circuit voltage in BHJ OSCs.

Keywords: charge carrier density, open-circuit voltage, organic solar cells, temperature

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3493 The Therapeutic Potential, Functions, and Use of Ibogaine

Authors: João Pedro Zanella, Michel J. O. Fagundes

Abstract:

Introduction: Drug use has been practised by humans universally for millennia, not excluding any population from these habits, however, the rampant drug use is a global concern due to the harm that affects the health of the world population. In this sense, it is observed the reduction of lasting and effective public policies for the resolution, increasing the demand for treatment services. With this comes ibogaine, an alkaloid derived from the root of an African bush (Tabernanthe Iboga), found mostly in Gabon and used widely by the native Bwiti population in rituals, and also other social groups, which demonstrates efficacy against chemical dependence, psychic and emotional disorders, opioid withdrawal was first confirmed by a study in rats done by Michailo Dzoljic and associates in 1988 and again in 1994. Methods: A brief description of the plant, its neurohumoral potential and the effects caused by ingested doses, in a simplified and objective way, will be discussed in the course of this abstract. Results: Ibogaine is not registered or passed by Anvisa, regarding safety and efficacy, and cannot be sold in Brazil. Its illegal trade reaches R$ 5 thousand for a session with the proceeds of the root, and its effect can last up to 72 hours, attributing Iboga's psychoactive effects to the alkaloid called ibogaine. The shrub where Ibogaine is located has pink and yellow flowers, and its fruit produced does not have psychoactive substances, but its root bark contains 6 to 7% indolic alkaloids. Besides extraction from the iboga plant, ibogaine hydrochloride can be semisynthesized from voacangine, another plant alkaloid that acts as a precursor. Its potential has the ability to perform multiple interactions with the neurotransmitter system, which are closely associated with addiction, including nicotinic, opioid and serotoninergic systems. Studies carried out by Edwards found that the doses administered of Iboga should be determined by a health professional when its purpose is to treat individuals for dependence on other drugs. Its use in small doses may cause an increase in sensibility, impaired vision and motor alterations; in moderate quantities, hallucinations, motor and neurological alterations and impaired vision; in high quantities it may cause hallucinations with personal events at a deeper level lasting up to 24 hours or more, followed by motor and visual alterations. Conclusion: The product extracted from the Iboga plant is of great importance in controlling addiction, reducing the need for the use of narcotics by patients, thus gaining a space of extreme importance in the treatment of users of psychoactive substances. It is remarkable the progress of the latest’s research about the usefulness of Ibogaine, and its benefits for certain treatments, even with the restriction of its sale in Brazil. Besides this, Ibogaine has an additional benefit of helping the patient to gain self-control over their destructive behaviours.

Keywords: alkaloids, dependence, Gabon, ibogaine

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3492 Structural and Electrical Properties of VO₂/ZnO Nanostructures

Authors: Sang-Wook Han, Zhenlan Jin, In-Hui Hwang, Chang-In Park

Abstract:

We examined structural and electrical properties of uniformly-oriented VO₂/ZnO nanostructures. VO₂ was deposited on ZnO templates by using a direct current-sputtering deposition. Scanning electron microscope and transmission electron microscope measurements indicated that b-oriented VO₂ were uniformly crystallized on ZnO templates with different lengths. VO₂/ZnO formed nanorods on ZnO nanorods with length longer than 250 nm. X-ray absorption fine structure at V K edge of VO₂/ZnO showed M1 and R phases of VO₂ at 30 and 100 ℃, respectively, suggesting structural phase transition between temperatures. Temperature-dependent resistance measurements of VO₂/ZnO nanostructures revealed metal-to-insulator transition at 65 ℃ and 55 ℃ during heating and cooling, respectively, regardless of ZnO length. The bond lengths of V-O and V-V pairs in VO₂/ZnO nanorods were somewhat distorted, and a substantial amount of structural disorder existed in the atomic pairs, compared to those of VO₂ films without ZnO. Resistance from VO₂/ZnO nanorods revealed a sharp MIT near 65 ℃ during heating and a hysteresis behavior. The resistance results suggest that microchannel for charge carriers exist nearly room temperature during cooling. VO₂/ZnO nanorods are quite stable and reproducible so that they can be widely used for practical applications to electronic devices, gas sensors, and ultra-fast switches, as examples.

Keywords: metal-to-insulator transition, VO₂, ZnO, XAFS, structural-phase transition

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3491 Understanding Evidence Dispersal Caused by the Effects of Using Unmanned Aerial Vehicles in Active Indoor Crime Scenes

Authors: Elizabeth Parrott, Harry Pointon, Frederic Bezombes, Heather Panter

Abstract:

Unmanned aerial vehicles (UAV’s) are making a profound effect within policing, forensic and fire service procedures worldwide. These intelligent devices have already proven useful in photographing and recording large-scale outdoor and indoor sites using orthomosaic and three-dimensional (3D) modelling techniques, for the purpose of capturing and recording sites during and post-incident. UAV’s are becoming an established tool as they are extending the reach of the photographer and offering new perspectives without the expense and restrictions of deploying full-scale aircraft. 3D reconstruction quality is directly linked to the resolution of captured images; therefore, close proximity flights are required for more detailed models. As technology advances deployment of UAVs in confined spaces is becoming more common. With this in mind, this study investigates the effects of UAV operation within active crimes scenes with regard to the dispersal of particulate evidence. To date, there has been little consideration given to the potential effects of using UAV’s within active crime scenes aside from a legislation point of view. Although potentially the technology can reduce the likelihood of contamination by replacing some of the roles of investigating practitioners. There is the risk of evidence dispersal caused by the effect of the strong airflow beneath the UAV, from the downwash of the propellers. The initial results of this study are therefore presented to determine the height of least effect at which to fly, and the commercial propeller type to choose to generate the smallest amount of disturbance from the dataset tested. In this study, a range of commercially available 4-inch propellers were chosen as a starting point due to the common availability and their small size makes them well suited for operation within confined spaces. To perform the testing, a rig was configured to support a single motor and propeller powered with a standalone mains power supply and controlled via a microcontroller. This was to mimic a complete throttle cycle and control the device to ensure repeatability. By removing the variances of battery packs and complex UAV structures to allow for a more robust setup. Therefore, the only changing factors were the propeller and operating height. The results were calculated via computer vision analysis of the recorded dispersal of the sample particles placed below the arm-mounted propeller. The aim of this initial study is to give practitioners an insight into the technology to use when operating within confined spaces as well as recognizing some of the issues caused by UAV’s within active crime scenes.

Keywords: dispersal, evidence, propeller, UAV

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3490 User Perceptions Deviation from the Producers’ Intended Meaning of a Healthcare Innovation

Authors: Helle Nissen

Abstract:

Physical objects surrounding people in healthcare environments are carriers of institutional logics materialized into the objects by its producers. However, institutional logics research lacks to inform us how logics become materialized and are perceived by producers vs. users of an object. The study is based on a 3-year longitudinal case study of a Danish Public Private Innovation project aiming to co-create an innovative healthcare bed commercialized to public psychiatric hospitals. The producers are a private metal firm and industrial designers from two Danish regions. The findings demonstrate that the metal firm and designers, as producers, negotiate about materializing different logics into the bed throughout the innovation process. An aesthetic logic is prioritized most, and the producers encode it with the intention to develop a bed that looks homely and less hospital-like compared to previous and existing healthcare beds. After the bed is put into use, the aesthetic logic is decoded by the users. Their perception of it differs significantly from the producers’ intended meaning, as the healthcare bed is perceived as sterile. The study has theoretical implications: It demonstrates how logics become materialized ‘here and now’, and it reveals logics as less governed by stable and clear meanings but rather as subject to changeable perceptions.

Keywords: co-creation, healthcare innovation, commercialization, institutional logics

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3489 Development of a Forecast-Supported Approach for the Continuous Pre-Planning of Mandatory Transportation Capacity for the Design of Sustainable Transport Chains: A Literature Review

Authors: Georg Brunnthaller, Sandra Stein, Wilfried Sihn

Abstract:

Transportation service providers are facing increasing volatility concerning future transport demand. Short-term planning horizons and planning uncertainties lead to reduced capacity utilization and increasing empty mileage. To overcome these challenges, a model is proposed to continuously pre-plan future transportation capacity in order to redesign and adjust the intermodal fleet accordingly. It is expected that the model will enable logistics service providers to organize more economically and ecologically sustainable transport chains in a more flexible way. To further describe these planning aspects, this paper gives an overview on transportation planning problems in a structured way. The focus is on strategic and tactical planning levels, comprising relevant fleet-sizing, service-network-design and choice-of-carriers-problems. Models and their developed solution techniques are presented, and the literature review is concluded with an outlook to our future research directions.

Keywords: freight transportation planning, multimodal, fleet-sizing, service network design, choice of transportation mode, review

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3488 Association of Lipoprotein Lipase Gene (HindIII rs320) Polymorphisms with Moderate Hypertriglyceridemia Secondary to Metabolic Syndrome

Authors: Meryem Abi-Ayad, Biagio Arcidiacono, Eusebio Chiefari, Daniela Foti, Mohamed Benyoucef, Antonio Brunetti

Abstract:

Lipoprotein Lipase (LPL) is a key enzyme for lipid metabolism; its genetic polymorphism can be a candidate for modulating lipids parameters in metabolic syndrome. The objective of the present study was to determine whether lipoproteins lipase polymorphisMetS (LPL-HindIII) could be associated with moderate hypertriglyceridemia (secondary to metabolism syndrome). The polymorphism Hind III (rs320) was assessed by PCR-RFLP in 51 MetS patients and 17 healthy controls from the hospital in Tlemcen. The logistic regression analyses showed no significant association with Hind III genotype and hypertriglyceridemia (TG ≥ 1,5g/l or TG lower treatment) (P=0,455), metabolic syndrome (P=0,455), hypertension (P=0,802) and type 2 diabetes (P=0,144). In terms of plasma biomarkers, although not statistically significant, there was a difference in TG levels (P > 0,05), which was lowest among carriers of the homogenous mutant allele (H-). In this study, there was no association between the rare allele (H-) and disease protection, and between the frequent allele (H+) and disease prevalence (hypertriglyceridemia, metabolic syndrome, hypertension, type 2 diabetes).

Keywords: moderate secondary hypertriglyceridemia, metabolic syndrome, lipids, polymorphism lipoprotein lipase, HindIII(rs320)

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3487 Study of Functional Relevant Conformational Mobility of β-2 Adrenoreceptor by Means of Molecular Dynamics Simulation

Authors: G. V. Novikov, V. S. Sivozhelezov, S. S. Kolesnikov, K. V. Shaitan

Abstract:

The study reports about the influence of binding of orthosteric ligands as well as point mutations on the conformational dynamics of β-2-adrenoreceptor. Using molecular dynamics simulation we found that there was a little fraction of active states of the receptor in its apo (ligand free) ensemble corresponded to its constitutive activity. Analysis of MD trajectories indicated that such spontaneous activation of the receptor is accompanied by the motion in intracellular part of its alpha-helices. Thus receptor’s constitutive activity directly results from its conformational dynamics. On the other hand the binding of a full agonist resulted in a significant shift of the initial equilibrium towards its active state. Finally, the binding of the inverse agonist stabilized the receptor in its inactive state. It is likely that the binding of inverse agonists might be a universal way of constitutive activity inhibition in vivo. Our results indicate that ligand binding redistribute pre-existing conformational degrees of freedom (in accordance to the Monod-Wyman-Changeux-Model) of the receptor rather than cause induced fit in it. Therefore, the ensemble of biologically relevant receptor conformations is encoded in its spatial structure, and individual conformations from that ensemble might be used by the cell in conformity with the physiological behaviour.

Keywords: seven-transmembrane receptors, constitutive activity, activation, x-ray crystallography, principal component analysis, molecular dynamics simulation

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3486 Analyzing Concrete Structures by Using Laser Induced Breakdown Spectroscopy

Authors: Nina Sankat, Gerd Wilsch, Cassian Gottlieb, Steven Millar, Tobias Guenther

Abstract:

Laser-Induced Breakdown Spectroscopy (LIBS) is a combination of laser ablation and optical emission spectroscopy, which in principle can simultaneously analyze all elements on the periodic table. Materials can be analyzed in terms of chemical composition in a two-dimensional, time efficient and minor destructive manner. These advantages predestine LIBS as a monitoring technique in the field of civil engineering. The decreasing service life of concrete infrastructures is a continuously growing problematic. A variety of intruding, harmful substances can damage the reinforcement or the concrete itself. To insure a sufficient service life a regular monitoring of the structure is necessary. LIBS offers many applications to accomplish a successful examination of the conditions of concrete structures. A selection of those applications are the 2D-evaluation of chlorine-, sodium- and sulfur-concentration, the identification of carbonation depths and the representation of the heterogeneity of concrete. LIBS obtains this information by using a pulsed laser with a short pulse length (some mJ), which is focused on the surfaces of the analyzed specimen, for this only an optical access is needed. Because of the high power density (some GW/cm²) a minimal amount of material is vaporized and transformed into a plasma. This plasma emits light depending on the chemical composition of the vaporized material. By analyzing the emitted light, information for every measurement point is gained. The chemical composition of the scanned area is visualized in a 2D-map with spatial resolutions up to 0.1 mm x 0.1 mm. Those 2D-maps can be converted into classic depth profiles, as typically seen for the results of chloride concentration provided by chemical analysis like potentiometric titration. However, the 2D-visualization offers many advantages like illustrating chlorine carrying cracks, direct imaging of the carbonation depth and in general allowing the separation of the aggregates from the cement paste. By calibrating the LIBS-System, not only qualitative but quantitative results can be obtained. Those quantitative results can also be based on the cement paste, while excluding the aggregates. An additional advantage of LIBS is its mobility. By using the mobile system, located at BAM, onsite measurements are feasible. The mobile LIBS-system was already used to obtain chloride, sodium and sulfur concentrations onsite of parking decks, bridges and sewage treatment plants even under hard conditions like ongoing construction work or rough weather. All those prospects make LIBS a promising method to secure the integrity of infrastructures in a sustainable manner.

Keywords: concrete, damage assessment, harmful substances, LIBS

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3485 Valorization of Natural Vegetable Substances from Tunisia: Purification of Two Food Additives, Anthocyanins and Locust Bean Gum

Authors: N. Bouzouita, A. Snoussi , H. Ben Haj Koubaier, I. Essaidi, M. M. Chaabouni, S. Zgoulli, P. Thonart

Abstract:

Color is one of the most important quality attributes for the food industry. Grape marc, a complex lignocellulosic material is one of the most abundant and worth less byproduct, generated after the pressing process. The development of the process of purification by micro filtration, ultra filtration, nano filtration and drying by atomization of the anthocyanins of Tunisian origin is the aim of this work. Locust bean gum is the ground endosperm of the seeds of carob fruit; owing to its remarkable water-binding properties, it is widely used to improve the texture of food and largely employed in food industry. The purification of LGB causes drastically reduced ash and proteins contents but important increase for galactomannan.

Keywords: Carob, food additives, grape pomace, locust bean gum, natural colorant, nano filtration, thickener, ultra filtration

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3484 The Effect of Metal-Organic Framework Pore Size to Hydrogen Generation of Ammonia Borane via Nanoconfinement

Authors: Jing-Yang Chung, Chi-Wei Liao, Jing Li, Bor Kae Chang, Cheng-Yu Wang

Abstract:

Chemical hydride ammonia borane (AB, NH3BH3) draws attentions to hydrogen energy researches for its high theoretical gravimetrical capacity (19.6 wt%). Nevertheless, the elevated AB decomposition temperatures (Td) and unwanted byproducts are main hurdles in practical application. It was reported that the byproducts and Td can be reduced with nanoconfinement technique, in which AB molecules are confined in porous materials, such as porous carbon, zeolite, metal-organic frameworks (MOFs), etc. Although nanoconfinement empirically shows effectiveness on hydrogen generation temperature reduction in AB, the theoretical mechanism is debatable. Low Td was reported in AB@IRMOF-1 (Zn4O(BDC)3, BDC = benzenedicarboxylate), where Zn atoms form closed metal clusters secondary building unit (SBU) with no exposed active sites. Other than nanosized hydride, it was also observed that catalyst addition facilitates AB decomposition in the composite of Li-catalyzed carbon CMK-3, MOF JUC-32-Y with exposed Y3+, etc. It is believed that nanosized AB is critical for lowering Td, while active sites eliminate byproducts. Nonetheless, some researchers claimed that it is the catalytic sites that are the critical factor to reduce Td, instead of the hydride size. The group physically ground AB with ZIF-8 (zeolitic imidazolate frameworks, (Zn(2-methylimidazolate)2)), and found similar reduced Td phenomenon, even though AB molecules were not ‘confined’ or forming nanoparticles by physical hand grinding. It shows the catalytic reaction, not nanoconfinement, leads to AB dehydrogenation promotion. In this research, we explored the possible criteria of hydrogen production temperature from nanoconfined AB in MOFs with different pore sizes and active sites. MOFs with metal SBU such as Zn (IRMOF), Zr (UiO), and Al (MIL-53), accompanying with various organic ligands (BDC and BPDC; BPDC = biphenyldicarboxylate) were modified with AB. Excess MOFs were used for AB size constrained in micropores estimated by revisiting Horvath-Kawazoe model. AB dissolved in methanol was added to MOFs crystalline with MOF pore volume to AB ratio 4:1, and the slurry was dried under vacuum to collect AB@MOF powders. With TPD-MS (temperature programmed desorption with mass spectroscopy), we observed Td was reduced with smaller MOF pores. For example, it was reduced from 100°C to 64°C when MOF micropore ~1 nm, while ~90°C with pore size up to 5 nm. The behavior of Td as a function of AB crystalline radius obeys thermodynamics when the Gibbs free energy of AB decomposition is zero, and no obvious correlation with metal type was observed. In conclusion, we discovered Td of AB is proportional to the reciprocal of MOF pore size, possibly stronger than the effect of active sites.

Keywords: ammonia borane, chemical hydride, metal-organic framework, nanoconfinement

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3483 Myanmar Consonants Recognition System Based on Lip Movements Using Active Contour Model

Authors: T. Thein, S. Kalyar Myo

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Human uses visual information for understanding the speech contents in noisy conditions or in situations where the audio signal is not available. The primary advantage of visual information is that it is not affected by the acoustic noise and cross talk among speakers. Using visual information from the lip movements can improve the accuracy and robustness of automatic speech recognition. However, a major challenge with most automatic lip reading system is to find a robust and efficient method for extracting the linguistically relevant speech information from a lip image sequence. This is a difficult task due to variation caused by different speakers, illumination, camera setting and the inherent low luminance and chrominance contrast between lip and non-lip region. Several researchers have been developing methods to overcome these problems; the one is lip reading. Moreover, it is well known that visual information about speech through lip reading is very useful for human speech recognition system. Lip reading is the technique of a comprehensive understanding of underlying speech by processing on the movement of lips. Therefore, lip reading system is one of the different supportive technologies for hearing impaired or elderly people, and it is an active research area. The need for lip reading system is ever increasing for every language. This research aims to develop a visual teaching method system for the hearing impaired persons in Myanmar, how to pronounce words precisely by identifying the features of lip movement. The proposed research will work a lip reading system for Myanmar Consonants, one syllable consonants (င (Nga)၊ ည (Nya)၊ မ (Ma)၊ လ (La)၊ ၀ (Wa)၊ သ (Tha)၊ ဟ (Ha)၊ အ (Ah) ) and two syllable consonants ( က(Ka Gyi)၊ ခ (Kha Gway)၊ ဂ (Ga Nge)၊ ဃ (Ga Gyi)၊ စ (Sa Lone)၊ ဆ (Sa Lain)၊ ဇ (Za Gwe) ၊ ဒ (Da Dway)၊ ဏ (Na Gyi)၊ န (Na Nge)၊ ပ (Pa Saug)၊ ဘ (Ba Gone)၊ ရ (Ya Gaug)၊ ဠ (La Gyi) ). In the proposed system, there are three subsystems, the first one is the lip localization system, which localizes the lips in the digital inputs. The next one is the feature extraction system, which extracts features of lip movement suitable for visual speech recognition. And the final one is the classification system. In the proposed research, Two Dimensional Discrete Cosine Transform (2D-DCT) and Linear Discriminant Analysis (LDA) with Active Contour Model (ACM) will be used for lip movement features extraction. Support Vector Machine (SVM) classifier is used for finding class parameter and class number in training set and testing set. Then, experiments will be carried out for the recognition accuracy of Myanmar consonants using the only visual information on lip movements which are useful for visual speech of Myanmar languages. The result will show the effectiveness of the lip movement recognition for Myanmar Consonants. This system will help the hearing impaired persons to use as the language learning application. This system can also be useful for normal hearing persons in noisy environments or conditions where they can find out what was said by other people without hearing voice.

Keywords: feature extraction, lip reading, lip localization, Active Contour Model (ACM), Linear Discriminant Analysis (LDA), Support Vector Machine (SVM), Two Dimensional Discrete Cosine Transform (2D-DCT)

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3482 Anti-Obesity Effects of Pteryxin in Peucedanum japonicum Thunb Leaves through Different Pathways of Adipogenesis In-Vitro

Authors: Ruwani N. Nugara, Masashi Inafuku, Kensaku Takara, Hironori Iwasaki, Hirosuke Oku

Abstract:

Pteryxin from the partially purified hexane phase (HP) of Peucedanum japonicum Thunb (PJT) was identified as the active compound related to anti-obesity. Thus, in this study we investigated the mechanisms related to anti-obesity activity in-vitro. The HP was fractionated, and effect on the triglyceride (TG) content was evaluated in 3T3-L1 and HepG2 cells. Comprehensive spectroscopic analyses were used to identify the structure of the active compound. The dose dependent effect of active constituent on the TG content, and the gene expressions related to adipogenesis, fatty acid catabolism, energy expenditure, lipolysis and lipogenesis (20 μg/mL) were examined in-vitro. Furthermore, higher dosage of pteryxin (50μg/mL) was tested against 20μg/mL in 3T3-L1 adipocytes. The mRNA were subjected to SOLiD next generation sequencer and the obtained data were analyzed by Ingenuity Pathway Analysis (IPA). The active constituent was identified as pteryxin, a known compound in PJT. However, its biological activities against obesity have not been reported previously. Pteryxin dose dependently suppressed TG content in both 3T3-L1 adipocytes and HepG2 hepatocytes (P < 0.05). Sterol regulatory element-binding protein-1 (SREBP1 c), Fatty acid synthase (FASN), and acetyl-CoA carboxylase-1 (ACC1) were downregulated in pteryxin-treated adipocytes (by 18.0, 36.1 and 38.2%; P < 0.05, respectively) and hepatocytes (by 72.3, 62.9 and 38.8%, respectively; P < 0.05) indicating its suppressive effects on fatty acid synthesis. The hormone-sensitive lipase (HSL), a lipid catabolising gene was upregulated (by 15.1%; P < 0.05) in pteryxin-treated adipocytes suggesting improved lipolysis. Concordantly, the adipocyte size marker gene, paternally expressed gene1/mesoderm specific transcript (MEST) was downregulated (by 42.8%; P < 0.05), further accelerating the lipolytic activity. The upregulated trend of uncoupling protein 2 (UCP2; by 77.5%; P < 0.05) reflected the improved energy expenditure due to pteryxin. The 50μg/mL dosage of pteryxin completely suppressed PPARγ, MEST, SREBP 1C, HSL, Adiponectin, Fatty Acid Binding Protein (FABP) 4, and UCP’s in 3T3-L1 adipocytes. The IPA suggested that pteryxin at 20μg/mL and 50μg/mL suppress obesity in two different pathways, whereas the WNT signaling pathway play a key role in the higher dose of pteryxin in preadipocyte stage. Pteryxin in PJT play the key role in regulating lipid metabolism related gene network and improving energy production in vitro. Thus, the results suggests pteryxin as a new natural compound to be used as an anti-obesity drug in pharmaceutical industry.

Keywords: obesity, peucedanum japonicum thunb, pteryxin, food science

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3481 Chipless RFID Capacity Enhancement Using the E-pulse Technique

Authors: Haythem H. Abdullah, Hesham Elkady

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With the fast increase in radio frequency identification (RFID) applications such as medical recording, library management, etc., the limitation of active tags stems from its need to external batteries as well as passive or active chips. The chipless RFID tag reduces the cost to a large extent but at the expense of utilizing the spectrum. The reduction of the cost of chipless RFID is due to the absence of the chip itself. The identification is done by utilizing the spectrum in such a way that the frequency response of the tags consists of some resonance frequencies that represent the bits. The system capacity is decided by the number of resonators within the pre-specified band. It is important to find a solution to enhance the spectrum utilization when using chipless RFID. Target identification is a process that results in a decision that a specific target is present or not. Several target identification schemes are present, but one of the most successful techniques in radar target identification in the oscillatory region is the extinction pulse technique (E-Pulse). The E-Pulse technique is used to identify targets via its characteristics (natural) modes. By introducing an innovative solution for chipless RFID reader and tag designs, the spectrum utilization goes to the optimum case. In this paper, a novel capacity enhancement scheme based on the E-pulse technique is introduced to improve the performance of the chipless RFID system.

Keywords: chipless RFID, E-pulse, natural modes, resonators

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3480 CFD Analysis of Multi-Phase Reacting Transport Phenomena in Discharge Process of Non-Aqueous Lithium-Air Battery

Authors: Jinliang Yuan, Jong-Sung Yu, Bengt Sundén

Abstract:

A computational fluid dynamics (CFD) model is developed for rechargeable non-aqueous electrolyte lithium-air batteries with a partial opening for oxygen supply to the cathode. Multi-phase transport phenomena occurred in the battery are considered, including dissolved lithium ions and oxygen gas in the liquid electrolyte, solid-phase electron transfer in the porous functional materials and liquid-phase charge transport in the electrolyte. These transport processes are coupled with the electrochemical reactions at the active surfaces, and effects of discharge reaction-generated solid Li2O2 on the transport properties and the electrochemical reaction rate are evaluated and implemented in the model. The predicted results are discussed and analyzed in terms of the spatial and transient distribution of various parameters, such as local oxygen concentration, reaction rate, variable solid Li2O2 volume fraction and porosity, as well as the effective diffusion coefficients. It is found that the effect of the solid Li2O2 product deposited at the solid active surfaces is significant on the transport phenomena and the overall battery performance.

Keywords: Computational Fluid Dynamics (CFD), modeling, multi-phase, transport phenomena, lithium-air battery

Procedia PDF Downloads 433
3479 Isolation and Characterization of Anti-melanoma (Skin Cancer) Compounds from Corchorus olitorius .L

Authors: Peramachi Sathiyamoorthy, Jacop Gopas, Avi Golan Goldhirsh

Abstract:

Corchorus olitorius is a leafy vegetable and an industrial crop. The herb has antioxidant, anti inflammatory, and anti-cancer properties. To assay the pharmaceutical properties, aqueous extracts of leaves and seeds from C. olitorius were tested against drug resistant melanoma cell line. The test showed LC50 of the extract was 0.08µg/ml. Aqueous seed extract exhibited higher melanoma inhibiting activity than leaf extract. Dialysis of seed extract showed that the active compound is less than 12 KDa. The compound with <3 KDa MW separated by microconcentration of seed extract showed 70.5 % inhibition of melanoma cell growth. Among the two fractions obtained by Gel filtration with G10 column, the first fraction at 1:2000 dilutions exhibited 100% inhibition of melanoma growth. The compound with Rf value 0.86 (MA4) isolated by TLC separation showed about 98% cytotoxicity against melanoma at 1: 1000 dilutions. Furthermore, HPLC separation of MA4 compound with Superdex 75 column resulted in 4 compounds. Out of 4, one compound showed melanoma inhibition. The active compound is identified by reagent methods as Strophanthidin. Further toxicological and clinical studies will lead to the development of a potential drug to treat drug resistant melanoma.

Keywords: corchorus olitorius, melanoma, drug development, strophanthidin

Procedia PDF Downloads 115
3478 Investigations on the Cytotoxicity and Antimicrobial Activities of Terezine E and 14-Hydroxyterezine D

Authors: Mariam Mojally, Randa Abdou, Wisal Bokhari, Sultan Sab, Mohammed Dawoud, Amjad Albohy

Abstract:

Secondary metabolites produced by endophytes are an excellent source of biologically active compounds. In our current study, we evaluated terezine E and 14-hydroxyterezine D for binding to the active site of histone deacetylase (PDB ID: 4CBT) and matrix metalloproteinase 9 (PDB ID: 4H3X) by molecular docking using AutoDock Vina software after having tested their cytotoxic activities on three cell lines (human ductal breast epithelial tumor cells (T47D)-HCC1937), human hepatocarcinoma cell line (HepG2)-HB8065), and human colorectal carcinoma cells (HCT-116)-TCP1006, purchased from ATCC, USA)). Additionally, their antimicrobial activities were investigated, and their minimum inhibitory concentration (MIC) values were determined against P. notatum and S. aureus by the broth microdilution method. Higher cytotoxicity was observed for terezine E against all tested cell lines compared to 14-hydroxyterezine D. Molecular docking results supported the high cytotoxicity of terezine E and showed higher binding affinity with 4CBT with an energy score of 9 kcal/mol. Terezine E showed higher antibacterial and antifungal activities than 14-hydroxyrerezine D: MIC values were 15.45 and 21.73 mg/mL against S. aureus and 8.61 and 11.54 mg/mL against P. notatum, respectively

Keywords: Terezine E, 14-Hydroxyterezine D, cytotoxicity, antimicrobial activity, molecular docking

Procedia PDF Downloads 49
3477 Physical Activity Patterns and Status of Adolescent Learners from Low and Middle Socio-Economic Status Communities in Kwazulu-Natal Province

Authors: Patrick Mkhanyiseli Zimu

Abstract:

A sedentary lifestyle and insufficient physical activity (PA) increases the risk of developing chronic non-communicable diseases (NCDs). Knowing the PA levels and patterns of adolescents from different socio-economic backgrounds is important to direct programs at schools and in communities to prevent NCDs risk factors, which can have long-term effects on the health of the adolescents. The study aimed to investigate adolescent PA levels, patterns, and influencing factors (age, gender, socio-economic status). The 353 participants (203 females and 150 males) from eight low socio-economic (LSES) and middle socio-economic (MSES) public secondary schools completed a Physical Activity Questionnaire for Adolescents (PAQ-A). The PAQ-A is a seven day recall instrument that assesses general estimates of PA levels and patterns for high school learners in Grades 9-12 and provides a summary of physical activity scores derived from seven items, each scored on a 5-point Likert scale. The seven items were PA during spare time and five domains (during physical education, lunch break, after school, in the evenings, on the weekend) and selecting one statement that described participant’s physical activity behaviour. The PA Levels (x̄=2.61, SD=.74) were below the international PA cut-off points of x̄=2.75. Physical education (PE) showed the highest PA score (x̄=3.05, SD=1.21) and lunch break showed the lowest PA score (x̄=2.09, SD=1.14). Positive correlations occurred between PA levels and SES (r=.122, p=0.022), and PA and gender (r=.223, p= 0.0001). LSES participant’s PA score was significantly lower (x̄=2.52; SD=.73) than those from MSES (x̄=2.70; SD=.74, p=0.022). Adolescents from low and middle socio-economic status communities are not sufficiently active. Their average PA score of 2.61 is below the PAQ-A global criterion referenced cut-off points of 2.75, which is considered sufficiently physically active for adolescents to ensure both short- and long-term health benefits. As adolescents are not sufficiently active, collaborative school and community PA programs need to be implemented to supplement physical education in order to prevent short- and long-term health problems.

Keywords: adolescents, health promotion, physical activity, physical education

Procedia PDF Downloads 79
3476 Sustainable Design Criteria for Beach Resorts to Enhance Physical Activity That Helps Improve Health and Well-being for Adults in Saudi Arabia

Authors: Noorh Albadi, Salha Khayyat

Abstract:

People's moods and well-being are affected by their environment. The built environment impacts one's level of activity and health. In order to enhance users' physical health, sustainable design strategies have been developed for the physical environment to improve users' health. This study aimed to determine whether adult resorts in Saudi Arabia meet standards that ensure physical wellness to identify the needed requirements. It will be significant to the Ministry of Tourism, Sports, developers, and designers. Physical activity affects human health physically and mentally. In Saudi Arabia, the percentage of people who practiced sports in the Kingdom in 2019 was 20.04% - males and females older than 15. On the other hand, there is a lack of physical activity in Saudi Arabia; 90% of the Kingdom's population spends more than two hours sitting down without moving, which puts them at risk of contracting a non-communicable disease. The lack of physical activity and movement led to an increase in the rate of obesity among Saudis by 59% in 2020 and consequently could cause chronic diseases or death. The literature generally endorses that leading an active lifestyle improves physical health and affects mental health. Therefore, the United Nations has set 17 sustainable development goals (SDGs) to ensure healthy lives and promote well-being for all ages. One of SDG3's targets is reducing mortality, which can be achieved by raising physical activity. In order to support sustainable design, many rating systems and strategies have been developed, such as WELL building, Leadership in Energy and Environmental Design, (LEED), Active design strategies, and RIPA plan of work. The survey was used to gather qualitative and quantitative information. It was designed based on the Active Design and WELL building theories targeting beach resorts visitors, professional and beginner athletes, and non-athletics to ask them about the beach resorts they visited in the Kingdom and whether they met the criteria of sports resorts and healthy and active design theories, in addition to gathering information about the preferences of physical activities in the Saudi society in terms of the type of activities that young people prefer, where they prefer to engage in and under any thermal and light conditions. The final section asks about the design of residential units in beach sports resorts, the data collected from 127 participants. Findings revealed that participants prefer outdoor activities in moderate weather and sunlight or the evening with moderate and sufficient lighting and that no beach sports resorts in the country are constructed to support sustainable design criteria for physical activity. Participants agreed that several measures that lessen tension at beach resorts and enhance movement and activity are needed by Saudi society. The study recommends designing resorts that meet the sustainable design criteria regarding physical activity in Saudi Arabia to increase physical activity to achieve psychological and physical benefits and avoid psychological and physical diseases related to physical inactivity.

Keywords: sustainable design, SDGs, active design strategies, well building, beach resort design

Procedia PDF Downloads 100
3475 Online Graduate Students’ Perspective on Engagement in Active Learning in the United States

Authors: Ehi E. Aimiuwu

Abstract:

As of 2017, many researchers in educational journals are still wondering if students are effectively and efficiently engaged in active learning in the online learning environment. The goal of this qualitative single case study and narrative research is to explore if students are actively engaged in their online learning. Seven online students in the United States from LinkedIn and residencies were interviewed for this study. Eleven online learning techniques from research were used as a framework.  Data collection tools were used for the study that included a digital audiotape, observation sheet, interview protocol, transcription, and NVivo 12 Plus qualitative software.  Data analysis process, member checking, and key themes were used to reach saturation. About 85.7% of students preferred individual grading. About 71.4% of students valued professor’s interacting 2-3 times weekly, participating through posts and responses, having good internet access, and using email.  Also, about 57.1% said students log in 2-3 times weekly to daily, professor’s social presence helps, regular punctuality in work submission, and prefer assessments style of research, essay, and case study.  About 42.9% appreciated syllabus usefulness and professor’s expertise.

Keywords: class facilitation, course management, online teaching, online education, student engagement

Procedia PDF Downloads 118
3474 Assessment of Exploitation Vulnerability of Quantum Communication Systems with Phase Encryption

Authors: Vladimir V. Nikulin, Bekmurza H. Aitchanov, Olimzhon A. Baimuratov

Abstract:

Quantum communication technology takes advantage of the intrinsic properties of laser carriers, such as very high data rates and low power requirements, to offer unprecedented data security. Quantum processes at the physical layer of encryption are used for signal encryption with very competitive performance characteristics. The ultimate range of applications for QC systems spans from fiber-based to free-space links and from secure banking operations to mobile airborne and space-borne networking where they are subjected to channel distortions. Under practical conditions, the channel can alter the optical wave front characteristics, including its phase. In addition, phase noise of the communication source and photo-detection noises alter the signal to bring additional ambiguity into the measurement process. If quantized values of photons are used to encrypt the signal, exploitation of quantum communication links becomes extremely difficult. In this paper, we present the results of analysis and simulation studies of the effects of noise on phase estimation for quantum systems with different number of encryption bases and operating at different power levels.

Keywords: encryption, phase distortion, quantum communication, quantum noise

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3473 Mid-Temperature Methane-Based Chemical Looping Reforming for Hydrogen Production via Iron-Based Oxygen Carrier Particles

Authors: Yang Li, Mingkai Liu, Qiong Rao, Zhongrui Gai, Ying Pan, Hongguang Jin

Abstract:

Hydrogen is an ideal and potential energy carrier due to its high energy efficiency and low pollution. An alternative and promising approach to hydrogen generation is the chemical looping steam reforming of methane (CL-SRM) over iron-based oxygen carriers. However, the process faces challenges such as high reaction temperature (>850 ℃) and low methane conversion. We demonstrate that Ni-mixed Fe-based oxygen carrier particles have significantly improved the methane conversion and hydrogen production rate in the range of 450-600 ℃ under atmospheric pressure. The effect on the reaction reactivity of oxygen carrier particles mixed with different Ni-based particle mass ratios has been determined in the continuous unit. More than 85% of methane conversion has been achieved at 600 ℃, and hydrogen can be produced in both reduction and oxidation steps. Moreover, the iron-based oxygen carrier particles exhibited good cyclic performance during 150 consecutive redox cycles at 600 ℃. The mid-temperature iron-based oxygen carrier particles, integrated with a moving-bed chemical looping system, might provide a powerful approach toward more efficient and scalable hydrogen production.

Keywords: chemical looping, hydrogen production, mid-temperature, oxygen carrier particles

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3472 Antifungal Activity of Commiphora myrrha L. against Some Air Fungi

Authors: Ahmed E. Al-Sabri, Mohamed A. Moslem, Sarfaraz Hadi

Abstract:

To avoid the harmful effects of the chemical fungicides on the human and minimize the environmental pollution, an alternative eco-friendly control strategies should be developed. The extract of Commiphora myhrra L. was tested against twenty fungal genera isolated from the indoor air collected from different rooms in King Saud University, Kingdom of Saudi Arabia. Disc diffusion test was modified for use in this study and the collected data was statistically analyzed. Variable antifungal efficacy of different myrrh extract was recorded against the investigated fungal genera. The efficacy of the extract was increased as the concentration increased. The highest growth inhibition (74.6%) was against Acremonium strictum followed by Trichoderma psuedokoningii (70.6%). On contrast, the lowest efficacy (12.7%) was against Ulocladium consortiale. It could be concluded that myrrh extract is promised as a source of substances from which of safer and eco-friendly could be used as antimicrobial agents against a number of pathogenic fungi.

Keywords: antifungal, myrrh, antimicrobial, medicinal plant

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3471 An Innovative Approach to Improve Skills of Students in Qatar University Spending in Virtual Class though LMS

Authors: Mohammad Shahid Jamil

Abstract:

In this study we have investigated students’ learning and satisfaction in one of the course offered in the Foundation Program at Qatar University. We implied innovative teaching methodology that emphasizes on enhancing students’ thinking skills, decision making, and problem solving skills. Some interesting results were found which can be used to further improve the teaching methodology. To make sure the full use of technology in Foundation Program at Qatar University has started implementing new ways of teaching Math course by using Blackboard as an innovative interactive tool to support standard teaching such as Discussion board, Virtual class, and Study plan in My Math Lab “MML”. In MML Study Plan is designed in such a way that the student can improve their skills wherever they face difficulties with in their Homework, Quiz or Test. Discussion board and Virtual Class are collaborative learning tools encourages students to engage outside of class time. These tools are useful to share students’ knowledge and learning experiences, promote independent and active learning and they helps students to improve their critical thinking skills through the learning process.

Keywords: blackboard, discussion board, critical thinking, active learning, independent learning, problem solving

Procedia PDF Downloads 412
3470 Development of Ferrous-Aluminum Alloys from Recyclable Material by High Energy Milling

Authors: Arnold S. Freitas Neto, Rodrigo E. Coelho, Erick S. Mendonça

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This study aimed to obtain an alloy of Iron and Aluminum in the proportion of 50% of atomicity for each constituent. Alloys were obtained by processing recycled aluminum and chips of 1200 series carbon steel in a high-energy mill. For the experiment, raw materials were processed thorough high energy milling before mixing the substances. Subsequently, the mixture of 1200 series carbon steel and Aluminum powder was carried out a milling process. Thereafter, hot compression was performed in a closed die in order to obtain the samples. The pieces underwent heat treatments, sintering and aging. Lastly, the composition and the mechanical properties of their hardness were analyzed. In this paper, results are compared with previous studies, which used iron powder of high purity instead of Carbon steel in the composition.

Keywords: Fe-Al alloys, high energy milling, metallography characterization, powder metallurgy

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3469 Isolation, Characterization and Screening of Antimicrobial Producing Actinomycetes from Sediments of Persian Gulf

Authors: H. Alijani, M. Jabari, S. Matroodi, H. Zolqarnein, A. Sharafi, I. Zamani

Abstract:

Actinomycetes, Gram-positive bacteria, are interesting as a main producer of secondary metabolites and are important industrially and pharmaceutically. The marine environment is a potential source for new actinomycetes, which can provide novel bioactive compounds and industrially important enzymes. The aims of this study were to isolate and identify novel actinomycetes from Persian Gulf sediments and screen these isolates for the production of secondary metabolites, especially antibiotics, Using phylogenetic (16S rRNA gene sequence), morphological and biochemical analyses. 15 different actinomycete strains from Persian Gulf sediments at a depth of 5-10 m were identified. DNA extraction was done using Cinnapure DNA Kit. PCR amplification of 16S rDNA gene was performed using F27 and R1492 primers. Phylogenetic tree analysis was performed using the MEGA 6 software. Most of the isolated strains belong to the genus namely Streptomyces (14), followed by Nocardiopsis (1). Antibacterial assay of the isolates supernatant was performed using a standard disc diffusion assay with replication (n=3). The results of disk diffusion assay showed that most active strain against Proteus volgaris and Bacillus cereus was AMJ1 (16.46±0.2mm and 13.78±0.2mm, respectively), against Salmonella sp. AMJ7 was the most effective strain (10.13±0.2mm), and AMJ1 and AHA5 showed more inhibitory activity against Escherichia coli (8.04±0.02 mm and 8.2±0.03 ). The AMJ6 strain showed best antibacterial activity against Klebsiella sp. (8.03±0.02mm). Antifungal activity of AMJ2 showed that it was most active strain against complex (16.05±0.02mm) and against Aspergillus flavus strain AMJ1 was most active strain (16.4±0.2mm) and highest antifungal activity against Trichophyton mentagrophytes, Microsporum gyp serum and Candida albicans, were shown by AHA1 (21.03±0.02mm), AHA3 and AHA7 (18±0.03mm), AMJ6 (21.03±0.2mm) respectively. Our results revealed that the marine actinomycetes of Persian Gulf sediments were potent source of novel antibiotics and bioactive compounds and indicated that the antimicrobial metabolites were extracellular. Most of the secondary metabolites and antibiotics are extracellular in nature and extracellular products of actinomycetes show potent antimicrobial activities.

Keywords: antibacterial activity, antifungal activity, marine actinomycetes, Persian Gulf

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3468 Attenuation of Homocysteine-Induced Cyclooxygenase-2 Expression in Human Monocytes by Fulvic Acid

Authors: Shao-Ju Chien, Yi-Chien Wu, Ting-Ying Huang, Li-Tsen Li, You-Jin Chen, Cheng-Nan Chen

Abstract:

Homocysteine and pro-inflammatory mediators such as cyclooxygenase-2 (COX-2) have been linked to vascular dysfunction and risks of cardiovascular diseases. Fulvic acid (FA) is class of compounds of humic substances and possesses various pharmacological properties. However, the effect of FA on inflammatory responses of the monocytes remains unclear. We investigated the regulatory effect of FA on homocysteine-induced COX-2 expression in human monocytes. Peripheral blood monocytes and U937 cells were kept as controls or pre-treated with FA, and then stimulated with homocysteine. The results show that pretreating monocytes with FA inhibited the homocysteine-induced COX-2 expression in a dose-dependent manner. The inhibitor for nuclear factor-kB (NF-kB) attenuated homocysteine-induced COX-2 expression. Our findings provide a molecular mechanism by which FA inhibit homocysteine-induced COX-2 expression in monocytes, and a basis for using FA in pharmaceutical therapy against inflammation.

Keywords: homocysteine, monocytes, cyclooxygenase-2, fulvic acid, anti-inflammation

Procedia PDF Downloads 576