Search results for: free radical scavenging activities

Authors: Zenaida M. De Guzman, Davison T. Baldos, Gilberto T. Diano, Jeff Darren G. Valdez, Levelyn Mitos Tolentino, Gina B. Abrera, Ma. Lucia Cobar, Cristina Gragasin

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One of the factors affecting the quality of brown rice is the free fatty acid produced from surface lipids. It is the purpose of the study to determine the effect of gamma radiation, packaging materials and age and variety of paddy on the surface free fatty acid content using two different brown rice variety, namely, RC-160 and SL-7, packed in two different packaging materials, namely, regular polyethylene bag and Super bag irradiated at 0.5 and 1.0 kGy. Brown rice was produced from 2-week old (Lot 1) and two months old paddy (Lot 2) and irradiated at the Co-60 Multipurpose Irradiation Facility, PNRI. The surface Free Fatty Acid (FFA) content was obtained following the AOCS Official Method (1982) with some modifications. The experiment was laid out using Split-Plot Randomized Control Block Design. Analysis of variance (ANOVA) showed that the effects of variety, age of paddy and interactions of both were both significant. The surface FFA of SL-7 variety was found to be significantly higher than the RC-160 variety for all radiation doses. Likewise, Lot 2 was observed to have higher surface FFA than Lot 1 regardless of packaging material and radiation dose. It was observed that the surface FFA of both varieties packed in both packaging materials increased significantly up to the 2nd or 3rd month of storage and remains the same until the 5th month. On the other hand, radiation dose did not significantly affect the surface free fatty acid content for all storage/sampling time while the packaging material significantly interacts with the type of variety and radiation dose. Gamma radiation was proven to have no significant effect on the surface free fatty acid at 0.5 and 1.0 kGy and further analyses are needed to determine the action of gamma radiation to the activity of enzyme (lipase-induced and microbial) responsible for the production of other lipolytic products and the effect of gamma radiation on the integrity of the packaging materials.

Keywords: brown rice, free fatty acid, gamma radiation, polyethylene bag

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Authors: Malika Yaici, Soraya Aloui, Sara Semchaoui

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Recognition of human activities from sensor data is an active research area, and the main objective is to obtain a high recognition rate. In this work, we propose a recognition system based on expert systems. The proposed system makes the recognition based on the objects, object states, and gestures, taking into account the context (the location of the objects and of the person performing the activity, the duration of the elementary actions, and the activity). This work focuses on complex activities which are decomposed into simple easy to recognize activities. The proposed method can be applied to any type of activity. The simulation results show the robustness of our system and its speed of decision.

Keywords: human activity recognition, ubiquitous computing, context-awareness, expert system

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Authors: V. Naga Sravan Kumar Varma, H. G. Shivakumar

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The aim of the study was to develop dual sensitive poly (N-isopropylacrylamide-co-acrylic acid) (PNA) nanogels(NGs) and studying its applications for Anti-Cancer therapy. NGs were fabricated by free radical polymerization using different amount of N-isopropylacrylamide and acrylic acid. A study for polymer composition over the effect on LCST in different pH was evaluated by measuring the absorbance at 500nm using UV spectrophotometer. Further selected NG’s were evaluated for change in hydrodynamic diameters in response to pH and temperature. NGs which could sharply respond to low pH value of cancer cells at body temperature were loaded with Fluorouracil (5-FU) using equilibrium swelling method and studied for drug release behaviour in different pH. A significant influence of NGs polymer composition over pH dependent LCST was observed. NGs which were spherical with an average particle size of 268nm at room temperature, shrinked forming an irregular shape when heated above to their respective LCST. 5FU loaded NGs did not intervene any difference in pH depended LCST behaviour of NGs. The in vitro drug release of NGs exhibited a pH and thermo-dependent control release. The cytoxicity study of blank carrier to MCF7 cell line showed no cytotoxicity. The results indicated that PNA NGs could be used as a potential drug carrier for anti-cancer therapy.

Keywords: pH and thermo-sensitive, nanogels, P(NIPAM-co-AAc), anti-cancer, 5-FU

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Authors: Kambiz Hassanzadeh, Seyedeh Shohreh Ebrahimi, Shahrbanoo Oryan, Arman Rahimmi, Esmael Izadpanah

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Parkinson’s disease is one of the most prevalent neurodegenerative diseases which occurs in elderly. There are convincing evidences that oxidative stress has an important role in both the initiation and progression of Parkinson’s disease. Thymoquinone (TQ) is shown to have antioxidant and anti-inflammatory properties in invitro and invivo studies. It is well documented that TQ acts as a free radical scavenger and prevents the cell damage. Therefore this study aimed to evaluate the effect of TQ on motor and non-motor symptoms in animal model of Parkinson’s disease. Male Wistar rats (10-12 months) received rotenone (1mg/kg/day, sc) to induce Parkinson’s disease model. Pretreatment with TQ (7.5 and 15 mg/kg/day, po) was administered one hour before the rotenone injection. Three motor tests (rotarod, rearing and bar tests) and two non-motor tests (forced swimming and elevated plus maze) were performed for behavioral assessment. Our results indicated that TQ significantly ameliorated the rotenone-induced motor dysfunction in rotarod and rearing tests also it could prevent the non-motor dysfunctions in forced swimming and elevated plus maze tests. In conclusion we found that TQ delayed the Parkinson's disease induction by rotenone and this effect might be related to its proved antioxidant effect.

Keywords: Parkinson's disease, thymoquinone, motor and non-motor symptoms, neurodegenerative disease

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Authors: P. Murugesan, G. Venkateswaran, V. A. Shanmuga Selvan

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Water used for brewing tea plays a major role in the quality of tea. Water with higher hardness gives very dark coloured brew. This study was conducted to determine the effect of water hardness and free residual chlorine on the quality of black tea liquor. Theaflavin (TF) and Thearubigin (TR) levels are lower in comparison with the tea brewed in distilled water. At the same time, there is an increase in High Polymerized Substance (HPS) and Total Liquor Colour (TLC). While water with higher hardness has a negative impact on tea brew, water with high concentration of free residual chlorine did not affect the quality of tea brew.

Keywords: Theaflavin, Thearubigin, high polymerised substance, total liquor colour, hardness, residual chlorine

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Authors: Abdelraheem M. Aly, Minh Tuan Nguyen, Sang-Wook Lee

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The incompressible smoothed particle hydrodynamics (ISPH) is used to simulate impact free surface flows. In the ISPH, pressure is evaluated by solving pressure Poisson equation using a semi-implicit algorithm based on the projection method. The current ISPH method is applied to simulate dam break flow over an inclined plane with different inclination angles. The effects of inclination angle in the velocity of wave front and pressure distribution is discussed. The impact of circular cylinder over water in tank has also been simulated using ISPH method. The computed pressures on the solid boundaries is studied and compared with the experimental results.

Keywords: incompressible smoothed particle hydrodynamics, free surface flow, inclined plane, water entry impact

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Authors: Khaing Yadana Swe, Lillie Dewan

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At present, the cascade PID control is widely used to control the super-heating temperature (main steam temperature). As the main steam temperature has the characteristics of large inertia, large time-delay, and time varying, etc., conventional PID control strategy can not achieve good control performance. In order to overcome the bad performance and deficiencies of main steam temperature control system, Model Free Adaptive Control (MFAC) P cascade control system is proposed in this paper. By substituting MFAC in PID of the main control loop of the main steam temperature control, it can overcome time delays, non-linearity, disturbance and time variation.

Keywords: model-free adaptive control, cascade control, adaptive control, PID

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Authors: M. Eskandarighadi, C. R. McGann

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It is observed from past experiences of earthquakes that local site conditions can significantly affect the strong ground motion characteristicssuch as frequency content, amplitude, and duration of seismic waves. The most common method for investigating site response is one-dimensional seismic site response analysis. The infinite horizontal length of the model and the homogeneous characteristic of the soil are crucial assumptions of this method. One boundary condition that can be used in the sides is tying the sides horizontally for vertical 1D wave propagation. However, 1D analysis cannot account for the 2D nature of wave propagation in the condition where the soil profile is not fully horizontal or has heterogeneity within layers. Therefore, 2D seismic site response analysis can be used to take all of these limitations into account for a better understanding of local site conditions. Different types of boundary conditions can be appliedin 2D site response models, such as tied boundary condition, massive columns, and free-field boundary condition. The tied boundary condition has been used in 1D analysis, which is useful for 1D wave propagation. Employing two massive columns at the sides is another approach for capturing the 2D nature of wave propagation. Free-field boundary condition can simulate the free-field motion that would exist far from the domain of interest. The goal for free-field boundary condition is to minimize the unwanted reflection from sides. This research focuses on the comparison between these methods with examples and discusses the details and limitations of each of these boundary conditions.

Keywords: boundary condition, free-field, massive columns, opensees, site response analysis, wave propagation

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Authors: Ramovatar, Neeraj Panwar

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Lead free Ba₀.₉₈Ca₀.₀₂SnxTi₁₋ₓO₃ (x = 0.01 and 0.05 mole %) ferroelectric ceramics have been synthesized by the solid-state reaction method with sintering at 1400 °C for 2 h. The room temperature x-ray diffraction (XRD) patterns identified the tetragonal phase for x = 0.01 composition whereas co-existence of tetragonal and orthorhombic phases for x =0.05 composition. Raman spectroscopy results corroborated with the XRD results at room temperature. The maximum dielectric properties (ɛm ~ 8591, tanδ ~ 0.018) were obtained for the compound with x = 0.01 at 5 kHz. Further, the tetragonal to cubic (TC) transition temperature was observed at 122 °C and 102 °C for the ceramics with x =0.01 and x = 0.05, respectively. The temperature dependent P-E loops also revealed the existence of TC at these particular temperature values. The energy storage density (Ed) of both compounds was calculated from room temperature P – E loops at an applied electric field of 20 kV/cm. The maximum Ed ~ 224 kJ/m³ was achieved for the sample with x = 0.01 as compared to 164 kJ/m³ for the x =0.05 composition. The value of Ed is comparable to other BaTiO₃ based lead free ferroelectric systems. Impedance spectroscopy analysis exhibited the bulk and grain boundary contributions above 300 °C under the frequency range 100 Hz to 1 MHz. The above properties make these ceramics suitable for energy storage devices.

Keywords: dielectric properties, energy storage properties, impedance spectroscopy, lead free ceramics

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Authors: Phakit Treesukol

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The purpose of this investigation is to ascertain Internet users’ behaviours towards companies’ public relations activities on social networking sites. In order to conduct a study of Internet users’ behaviour, data was collected using the quota sampling method from a total of 100 Internet users who are members of SNS and used the Internet during the period 10 December 2009 to 9 January 2010. An online self-administrated questionnaire was distributed through Facebook, Hi5 and Twitter to Internet users by using snowball sampling technique. Results of the study showed that the majority of the respondents were using social networking sites with the main purpose to contact their friends. Presently, most of the respondents were not regularly receiving companies’ public relations activities on social networking sites. The highest frequency of survey responses by the respondents was for hiding or deleting information introducing new products or services from companies on SNS also as well.

Keywords: media uses and gratification, online activities, public relations activities, social networking sites

Procedia PDF Downloads 253

Authors: Siti Sofo Ismail, Siti Noraina Wahida Mohd Alwi, Mohamad Hafiz Ameran, Masrudin M. Yusoff

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Locating clandestine cadaver is crucially important in forensic investigations. However, it requires a lot of man power, costly and time consuming. Therefore, the development of a new method to locate the clandestine graves is urgently needed as the cases involve burial of cadaver in different types of soils under tropical climates are still not well explored. This study focused on the burial in mangrove and oil palm plantation soils, comparing the fatty acid distributions in different soil acidities. A stimulated burial experiment was conducted using domestic pig (Sus scrofa) to substitute human tissues. Approximately 20g of pig fatty flesh was allowed to decompose in mangrove and oil palm plantation soils, mimicking burial in a shallow grave. The associated soils were collected at different designated sampling points, corresponding different decomposition stages. Modified Bligh-Dyer Extraction method was applied to extract the soil free fatty acids. Then, the obtained free fatty acids were analyzed with gas chromatography-flame ionization (GC-FID). A similar fatty acid distribution was observed for both mangrove and oil palm plantations soils. Palmitic acid (C₁₆) was the most abundance of free fatty acid, followed by stearic acid (C₁₈). However, the concentration of palmitic acid (C₁₆) higher in oil palm plantation compare to mangrove soils. Conclusion, the decomposition rate of cadaver can be affected by different type of soils.

Keywords: clandestine grave, burial, soils, free fatty acid

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Authors: Suparna Roy, P. Anantharaman

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The aim of this work is to estimate some in-vitro antioxidant activities and total phenols of various extracts such as aqueous, acetone, ethanol, methanol extract of seaweeds and pigments content by Spectrophotometric method. The seaweeds were collected during 2016 from Rameshwaram, southeast coast of India. Among four different extracts, aqueous extracts from all seaweeds had minimum activity than acetone, methanol and ethanol. The Rhodophyta and Phaeophyta had high antioxidant activity in comparing to Chlorophyta. The highest total antioxidant activity was found in acetone extract fromTurbinaria decurrens (98.97±0.00%), followed by its methanol extract (98.81±0.60%) and ethanol extract (98.58±0.53%). The highest reducing power and H2O2 scavenging activity were found in acetone extract of Caulerpa racemosa (383.25±1.04%), and methanol extract from Caulerpa racemosa var. macrophysa (24.91±0.49%). The methanol extract from Caulerpa scalpelliformis contained the highest total phenol (85.23±0.12%). The Chloro-a and Chloro-b contents were the highest in Gracilaria foliifera (13.69±0.38% mg/gm dry wt.) and Caulerpa racemosa var. macrophysa (9.12 ±0.12% mg/gm dry wt.) likewise carotenoid was also the highest in Gracilaria foliifera (0.054±0.0003% mg/gm dry wt.) and Caulerpa racemosa var. macrophysa (0.04 ±0.002% mg/gm dry wt.). It can be concluded from this study that some seaweed extract can be used for natural antioxidant production, after further characterization to negotiate the side effect of synthetic, market available antioxidants.

Keywords: seaweeds, antioxidant, total phenol, pigment, Olaikuda, Vadakkadu, Rameshwaram

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Authors: Mohammed Aljoma

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In this paper, a developed prototype for the scheduling of repetitive activities in height-rise buildings was presented. The activities that describe the behavior of the most of activities in multi-storey buildings are scheduled using the developed approach. The prototype combines three methods to attain the optimized planning. The methods include Critical Path Method (CPM), Gantt and Line of Balance (LOB). The developed prototype; POTER is used to schedule repetitive and non-repetitive activities with respect to all constraints that can be automatically generated using a generic database. The prototype uses the method of genetic algorithms for optimizing the planning process. As a result, this approach enables contracting organizations to evaluate various planning solutions that are calculated, tested and classified by POTER to attain an optimal time-cost equilibrium according to their own criteria of time or coast.

Keywords: planning scheduling, genetic algorithms, repetitive activity, construction management, planning, scheduling, risk management, project duration

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Authors: Azza H. El-Medany, Hanan H. Hagar, Jamila H. El-Medany

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Ulcerative colitis (UC) is one of chronic inflammatory diseases primarily affecting colon with unknown etiology. Some researches papers mentioned the possibility of the use of drugs that affect the angiotensin II in reducing the complication of ulcerative colitis. The aim of the present study is to evaluate the potential protective and therapeutic effects of captopril and valsartan on ulcerative colitis induced experimentally in rats using acetic acid. The results were assessed by histological assessment of colonic tissues and measurement of malondialdehyde (MDA), tumor necrosis factor (TNF-α), transforming growth factor (TGF-1B), angiotensin converting enzyme (ACE), reduced glutathione (GSH) and platelet activating factor (PAF) levels in colonic tissues. Oral pre-treatment with captopril or valsartan in a dose of 30 mgkg-1 body weight for 2 weeks before induction of colitis (prophylactic groups) and continuously for 2 weeks after induction (therapeutic groups) significantly reduce MDA, TNF-α, PAF, TGF-1B and ACE levels in colonic tissues as compared to acetic acid control group. Also, a significant increase in GSH level was observed in colonic tissues. Captopril and valsartan attenuated the macroscopic and microscopic colonic damage induced by acetic acid. These results suggest that either captopril or valsartan may be effective as prophylactic or treatment of UC through inhibition of ACE and scavenging effect on oxygen-derived free radicals.

Keywords: captopril, valsartan, angiotensin converting enzyme, reduced glutathione, tumor necrosis factor

Procedia PDF Downloads 264

Authors: Wongsakorn Charoenpanitseri

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The total chromatic number χ"(G) of a graph G is the minimum number of colors needed to color the elements (vertices and edges) of G such that no incident or adjacent pair of elements receive the same color Let G be a graph with maximum degree Δ(G). Considering a total coloring of G and focusing on a vertex with maximum degree. A vertex with maximum degree needs a color and all Δ(G) edges incident to this vertex need more Δ(G) + 1 distinct colors. To color all vertices and all edges of G, it requires at least Δ(G) + 1 colors. That is, χ"(G) is at least Δ(G) + 1. However, no one can find a graph G with the total chromatic number which is greater than Δ(G) + 2. The Total Coloring Conjecture states that for every graph G, χ"(G) is at most Δ(G) + 2. In this paper, we prove that the Total Coloring Conjectur for a Δ-claw-free 3-degenerated graph. That is, we prove that the total chromatic number of every Δ-claw-free 3-degenerated graph is at most Δ(G) + 2.

Keywords: total colorings, the total chromatic number, 3-degenerated, CLAW-FREE

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Authors: Aichun Feng, Zhi-Min Chen, Jing Tang Xing

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A two-dimensional linear wave-body interaction problem can be solved using a desingularized integral method by placing free surface Rankine sources over calm water surface and satisfying boundary conditions at prescribed collocation points on the calm water surface. A new free-surface Rankine source distribution scheme, determined by the intersection points of free surface and body surface, is developed to reduce numerical computation cost. Associated with this, a new treatment is given to the intersection point. The present scheme results are in good agreement with traditional numerical results and measurements.

Keywords: source point distribution, panel method, Rankine source, desingularized algorithm

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Authors: Assia Amri, Naima Layachi, Ali Ladjama

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The characterization of some Algerian honey was carried out on the basis of their physico-chemical properties: moisture,hydroxy methyl furfural, diastase activity, pH,free, total and lactonic acidity, electrical conductivity, minerals and proline content. Studied samples are found to be low in moisture and therefore safe from fermentation, low in HMF level and high in diastase activity. Additionally the diastase activity and the HMF content are widely recognized parameters indicating the freshness of honey. Phenolic compounds present in honey are classified into two groups - simple phenols and polyphenols. The simple phenols in honey are various phenol acids, but polyphenols are various flavonoids and flavonides. The aim of our work was to determine antioxidant properties of various Algerian honey samples–the total phenol content, total flavonoids content, as well as honey anti radical activity.The quality of honey samples differs on account of various factors such as season, packaging and processing conditions, floral source, geographical origin and storage period. It is important that precautions should be taken to ensure standardization and rationalization of beekeeping techniques, manufacturing procedures and storing processes to improve honey quality.

Keywords: honey, physico-chemical characterization, phenolic coumpound, HMF, diastase activity

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Authors: Niloofar Zebarjad

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This research aims at finding a tool to provide basketball players with real-time audio feedback on their shooting form in free throw shots. Free throws played a pivotal role in taking the lead in fierce competitions. The major problem in performing an accurate free throw seems to be improper training. Since the arm movement during the free throw shot is complex, the coach or the athlete might miss the movement details during practice. Hence, there is a necessity to create a system that measures arm movements' critical characteristics and control for improper kinematics. The proposed setup in this study quantifies arm kinematics and provides real-time feedback as an audio signal consisting of a gyroscope sensor. Spatial shoulder angle data are transmitted in a mobile application in real-time and can be saved and processed for statistical and analysis purposes. The proposed system is easy to use, inexpensive, portable, and real-time applicable. Objectives: This research aims to modify and control the free throw using audio feedback and determine if and to what extent the new setup reduces errors in arm formations during throws and finally assesses the successful throw rate. Methods: One group of elite basketball athletes and two novice athletes (control and study group) participated in this study. Each group contains 5 participants being studied in three separate sessions over a week. Results: Empirical results showed enhancements in the free throw shooting style, shot pocket (SP), and locked position (LP). The mean values of shoulder angle were controlled on 25° and 45° for SP and LP, respectively, recommended by valid FIBA references. Conclusion: Throughout the experiments, the system helped correct and control the shoulder angles toward the targeted pattern of shot pocket (SP) and locked position (LP). According to the desired results for arm motion, adding another sensor to measure and control the elbow angle is recommended.

Keywords: audio-feedback, basketball, free-throw, locked-position, motor-control, shot-pocket

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Authors: Win-Jin Chang, Haw-Long Lee, Yu-Ching Yang

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In this study, we use the atomic-scale finite element method to investigate the mechanical behavior of the armchair- and zigzag-structured nanoporous graphene sheets with the clamped-free-free-free boundary condition under tension and shear loadings. The effect of porosity on Young’s modulus and shear modulus of nanoporous graphene sheets is obvious. For the armchair- and zigzag-structured nanoporous graphene sheets, Young’s modulus and shear modulus decreases with increasing porosity. Young’s modulus and shear modulus of zigzag graphene are larger than that of armchair one for the same porosity. The results are useful for application in the design of nanoporous graphene sheets.

Keywords: graphene, nanoporous, Young's modulus, shear modulus

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Authors: Stanislav Perepechko

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Industrial companies - one of the major sources of harmful substances to the atmosphere. The main cause of pollution on the concrete plants are cement dust emissions. All the cement silos, pneumatic transport, and ventilation systems equipped with filters, to avoid this. Today, many Russian companies have to decide on replacement morally and physically outdated filters and guided back to the electrostatic filters as usual equipment. The offered way of a cleaning of waste-free filtering of air differs in the fact that a filtering medium of the filter is used in concrete manufacture. Basalt is widespread and pollution-free material. In the course of cleaning, one part of basalt fiber and cement immediately goes to the mixer through flow-control units of initial basalt fiber and cement. Another part of basalt fiber goes to filters for purification of the air used in systems of an air lift, and ventilating emissions passes through them, and with trapped particles also goes to the mixer through flow-control units of the basalt fiber fulfilled in filters. At the same time, regulators are adjusted in such a way that total supply of basalt fiber and cement into the mixer remains invariable and corresponds to a given technological mode.

Keywords: waste-free air filtration, concrete, basalt fiber, building automation

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Authors: Salwa A. H. Hamdi, Maha A. M. El-Shazly, Mona Fathi Fol, Hanan S. Mossalem, Mosad A. Ghareeb, Amina M. Ibrahim

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One of the most distinctive and defining features of cephalopods squid, cuttlefish, and Octopus is their inking behavior. Their ink, which is blackened by melanin but also contains other constituents, has been used by humans in various ways for millennia. The present study aims to investigate the chemical profiling of the Octopus vulgaris ink extract and to evaluate its antioxidant, antimicrobial, and anti-schistosomal activities. The present results showed that GC-MS examination of Octopus vulgaris ink comprises 21 compounds. The main detected compounds are (E)-1, 2, 3, 4-Tetra (4-phenylphenyl)-2-butene-1,4-dione, Lipo-3-episapelin A, and 5,10-Dihexyltetrabenzoporphyrin. Results showed that the octopus ink had antioxidant capacity and the capability to mask DPPH free radicals in comparison with ascorbic acid. Octopus Vulgaris ink extract had inhibitory action against three gram-positive bacteria, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis, and three gram-negative bacteria, Neisseria gonorrhoeae, Escherichia coli, and Pseudomonas aeuroginosa. Additionally, the extracted ink revealed antifungal activity against Aspergillus flavus and yeast as Candida albicans. The obtained data indicated the effectiveness of ink extract in pharmaceutical industries as an antioxidant, antimicrobial and antischistosomicidal

Keywords: antimicrobial, antioxidant, ink, octopus vulgaris

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Authors: Saeid Sahmani

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Due to size-dependent behavior of nanostrustures, the classical continuum models are not applicable for the analyses at this submicrion size. Surface stress effect is one of the most important matters which make the nanoscale structures to have different properties compared to the conventional structures due to high surface to volume ratio. In the present study, free vibration characteristics of nanoplates are investigated including surface stress effects. To this end, non-classical plate model based on Gurtin-Murdoch elasticity theory is proposed to evaluate the surface stress effects on the vibrational behavior of nanoplates subjected to different boundary conditions. Generalized differential quadrature (GDQ) method is employed to discretize the governing non-classical differential equations along with various edge supports. Selected numerical results are given to demonstrate the distinction between the behavior of nanoplates predicted by the classical and present non-classical plate models that leads to illustrate the great influence of surface stress effect. It is observed that this influence quite depends on the magnitude of the surface elastic constants which are relevant to the selected material.

Keywords: nanomechanics, surface stress, free vibration, GDQ method, small scale effect

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Authors: Ayodele Odularu, Peter Ajibade, Albert Bolhuis

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This study aimed at assessing the antibacterial activities of four zinc (II) complexes. Zinc (II) complexes of nitrogen, oxygen and sulfur coordination modes were synthesized using direct substitution reaction. The characterization techniques involved physicochemical properties (molar conductivity) and spectroscopic techniques. The molar conductivity gave the non-electrolytic nature of zinc (II) complexes. The spectral studies of zinc (II) complexes were done using electronic spectra (UV-Vis) and Fourier Transform Infra-red Spectroscopy (FT-IR). Spectral data from the spectroscopic studies confirmed the coordination of the mixed ligands with zinc (II) ion. The antibacterial activities of zinc(II) complexes of were all in supportive of Overtone’s concept and Tweedy’s theory of chelation for bacterial strains of S. aureus MRSA252 and E coli MC4100 because the zones of inhibition were greater than the corresponding ligands. In summary, all zinc (II) complexes of ZEPY, ZE1PH, ZE1PY and ZE135PY all have potentials for antibacterial activities.

Keywords: antibacterial activities, spectral studies, syntheses, zinc(II) complexes

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Authors: O. A. Babalola, A. F Adekunle, F. Oladeji, A. T. Osungbade, O. A. Akinlaja

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Optimizing microbiological activities in an organic crop production system is crucial to the realization of optimum growth and development of the crops. Field and pot experiments were conducted to assess soil microbial activities, growth and yield of tomato varieties in response to 4 rates of composted plant and animal residues. The compost rates were 0, 5, 10 and 20 t ha-1, and improved Ibadan and Ibadan local constituted the varieties. Fungi population, microbial biomass nitrogen, cellulase and proteinase activities were significantly higher (P≤ 0.05) at the rhizosphere of the local variety than that of improved variety. This led to a significantly higher number of branches, plant height, leaf area, number of fruits and less days to maturity in the local variety. Furthermore, compost-amended soil had significantly higher microbial populations, microbial biomass N, P and C, enzyme activities, soil N, P and organic carbon than control, but amendment of 20 t ha-1 gave significantly higher values than other compost rates. Consequently, growth parameters and tissue N significantly increased in all compost treatments while dry matter yield and weight of fruits were significantly higher in soil amended with 20 t ha-1. Correlation analysis showed that microbial activities at 6 weeks after transplanting (6 WAT) were more consistently and highly correlated with growth and yield parameters. It was concluded that microbial activities could be optimized to improve the yield of the two tomato varieties in an organic production system, through the application of compost, particularly at 20 t ha-1.

Keywords: compost, microbial activities, microbial contribution, tomato growth and yield

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Authors: Emmanuel Omokhuale

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A mathematical model is presented to study free convective boundary layer flow in a semi-infinite vertical cylinder with heat sink effect in a porous medium. The governing dimensional governing partial differential equations (PDEs) with corresponding initial and boundary conditions are approximated and solved numerically employing finite difference method (FDM) the implicit type. Stability and convergence of the scheme are also established. Furthermore, the influence of significant physical parameters on the flow characteristics was analysed and shown graphically. The obtained results are benchmarked with previously published works in order to access the accuracy of the numerical method and found to be in good agreement.

Keywords: free convection flow, vertical cylinder, implicit finite difference method, heat sink and porous medium

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Authors: Thilivhali Emmanuel Tshikalange, Phiwokuhle Mamba

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Ten medicinal plants used traditionally in the treatment of sexually transmitted diseases (STDs) and urinary tract infections (UTIs) were selected from an ethnobotanical database developed in Mpumalanga. The plants were investigated for their antimicrobial activity against five bacterial strains (Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Neisseria gonorrhoeae and Staphylococcus aureus) and one fungal strain (Candida albicans). Eight of the plants inhibited the growth of all microorganisms at a concentration range of 0.4 mg/ml to 12.5 mg/ml. Acacia karroo showed the most promising antimicrobial activity, with a minimum inhibitory concentration (MIC) of 0.4 mg/ml on Staphylococcus aureus and 0.8 mg/ml on Neisseria gonorrhoeae. All ten plants were further investigated for their antioxidant activities using the DPPH scavenging method. Acacia karroo and Rhoicissus tridentata subsp. cuneifolia showed good antioxidant activity with IC50 values of 0.83 mg/ml and 0.06 mg/ml, respectively. The toxicity of plants was determined using the XTT reduction method against Vero cells. None of the ten plants showed toxicity on the cells. The obtained results confirmed that Acacia karroo and possibly Rhoicissus tridentata subsp. cuneifolia have the potential of being used as antimicrobial agents in the treatment of STDs and UTIs. These results support and validate traditional use of medicinal plants studied.

Keywords: antimicrobial, antioxidant, Neisseria gonorrhoeae, sexually transmitted diseases

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Authors: Ting-I Lin

Abstract:

Purpose: This article explores the care experience of a 34-year-old female breast cancer patient who was admitted to the intensive care unit after undergoing a modified radical mastectomy. The patient discovered a lump in her right breast during a self-examination and, after mammography and ultrasound-guided biopsy, was diagnosed with a malignant tumor in the right breast. The tumor measured 1.5 x 1.4 x 2 cm, and the patient underwent a modified radical mastectomy. Postoperatively, she exhibited feelings of inferiority due to changes in her appearance. Method: During the care period, we engaged in conversations, observations, and active listening, using Gordon's Eleven Functional Health Patterns for a comprehensive assessment. In collaboration with the critical care team, a psychologist, and an oncology case manager, we conducted an interdisciplinary discussion and reached a consensus on key nursing issues. These included pain related to postoperative tumor excision and disturbed body image due to changes in appearance after surgery. Result: During the care period, a private space was provided to encourage the patient to express her feelings about her altered body image. Communication was conducted through active listening and a non-judgmental approach. The patient's anxiety level, as measured by the depression and anxiety scale, decreased from moderate to mild, and she was able to sleep for 6-8 hours at night. The oncology case manager was invited to provide education on breast reconstruction using breast models and videos to both the patient and her husband. This helped rebuild the patient's confidence. With the patient's consent, a support group was arranged where a peer with a similar experience shared her journey, offering emotional support and encouragement. This helped alleviate the psychological stress and shock caused by the cancer diagnosis. Additionally, pain management was achieved through adjusting the dosage of analgesics, administering Ultracet 37.5 mg/325 mg 1# Q6H PO, along with distraction techniques and acupressure therapy. These interventions helped the patient relax and alleviate discomfort, maintaining her pain score at a manageable level of 3, indicating mild pain. Conclusion: Disturbance in body image can cause significant psychological stress for patients. Through support group discussions, encouraging patients to express their feelings, and providing appropriate education on breast reconstruction and dressing techniques, the patient's self-concept was positively reinforced, and her emotions were stabilized. This led to renewed self-worth and confidence.

Keywords: breast cancer, modified radical mastectomy, acupressure therapy, Gordon's 11 functional health patterns

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Authors: Ana Beltran Sanahuja, A. Valdés García, Saray Lopez De Pablo Gallego, Maria Soledad Prats Moya

Abstract:

Tomato consumption has greatly increased worldwide in the last few years, mostly due to a growing demand for products like sofrito. In this sense, regular consumption of tomato-based products has been consistently associated with a reduction in the incidence of chronic degenerative diseases. The sofrito is a homemade tomato sauce typical of the Mediterranean area, which contains as main ingredients: tomato, onion, garlic and olive oil. There are also sofrito’s variations by adding other spices which bring at the same time not only color, flavor, smell and or aroma; they also provide medicinal properties, due to their antioxidant power. This protective effect has mainly been attributed to the predominant bioactive compounds present in sofrito, such as lycopene and other carotenoids as well as more than 40 different polyphenols. Regarding the cooking process, it is known that it can modify the properties and the availability of nutrients in sofrito; however, there is not enough information regarding this issue. For this reason, the aim of the present work is to evaluate the cooking effect on the antioxidant capacity of different variants of tomato-based sofrito combined with other spices, through the analysis of total phenols content (TPC) and to evaluate the antioxidant capacity by using the method of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). Based on the results obtained, it can be confirmed that the basic sofrito composed of tomato, onion, garlic and olive oil and the sofrito with 1 g of rosemary added, are the ones with the highest content of phenols presenting greater antioxidant power than other industrial sofrito, and that of other variables of sofrito with added thyme or higher amounts of garlic. Moreover, it has been observed that in the elaboration of the tomato-based sofrito, it is possible to cook until 60 minutes, since the cooking process increases the bioavailability of the carotenoids when breaking the cell walls, which weakens the binding forces between the carotenoids and increases the levels of antioxidants present, confirmed both with the TPC and DPPH methods. It can be concluded that the cooking process of different variants of tomato-based sofrito, including spices, can improve the antioxidant capacity. The synergistic effects of different antioxidants may have a greater protective effect; increasing, also, the digestibility of proteins. In addition, the antioxidants help to deactivate the free radicals of diseases such as atherosclerosis, aging, immune suppression, cancer, and diabetes.

Keywords: antioxidants, cooking process, phenols sofrito

Procedia PDF Downloads 138

Authors: Ahmed F. Ghanem, Marwa I. Wahba, Asmaa N. El-Dein, Mohamed A. EL-Raey, Ghada E.A. Awad

Abstract:

Numerous attempts are being performed in order to formulate suitable packaging materials for meat products. However, to the best of our knowledge, the incorporation of free hibiscus extract or its microcapsules in the pure polyvinyl alcohol (PVA) matrix as packaging materials for meats is seldom reported. Therefore, this study aims at protection of the aqueous crude extract of hibiscus flowers utilizing spry drying encapsulation technique. Fourier transform infrared (FTIR), scanning electron microscope (SEM), and zetasizer results confirmed the successful formation of assembled capsules via strong interactions, spherical rough microparticles, and ~ 235 nm of particle size, respectively. Also, the obtained microcapsules enjoy high thermal stability, unlike the free extract. Then, the obtained spray-dried particles were incorporated into the casting solution of the pure PVA film with a concentration 10 wt. %. The segregated free-standing composite films were investigated, compared to the neat matrix, with several characterization techniques such as FTIR, SEM, thermal gravimetric analysis (TGA), mechanical tester, contact angle, water vapor permeability, and oxygen transmission. The results demonstrated variations in the physicochemical properties of the PVA film after the inclusion of the free and the extract microcapsules. Moreover, biological studies emphasized the biocidal potential of the hybrid films against microorganisms contaminating the meat. Specifically, the microcapsules imparted not only antimicrobial but also antioxidant activities to PVA. Application of the prepared films on the real meat samples displayed low bacterial growth with a slight increase in the pH over the storage time up to 10 days at 4 oC which further proved the meat safety. Moreover, the colors of the films did not significantly changed except after 21 days indicating the spoilage of the meat samples. No doubt, the dual-functional of prepared composite films pave the way towards combined active/smart food packaging applications. This would play a vital role in the food hygiene, including also quality control and assurance.

Keywords: PVA, hibiscus, extraction, encapsulation, active packaging, smart and intelligent packaging, meat spoilage

Procedia PDF Downloads 81

Authors: Zubi Sadiq, Ghazala Yaqub, Almas Hamid

Abstract:

We wish to report herein a very stimulating variation in Fischer indole reaction by adopting solvent and catalyst free conditions. A concise synthesis of dinitro tetrahydrocarbazole derivative 3 was introduced without the use of any accelerating agent at ambient temperature with fairly good yield. Product was fully corroborated by UV, FTIR, 1H NMR, 13C NMR, MS, and CHN analysis.

Keywords: fischer indole reaction, neutral medium, solvent free synthesis, tetrahydrocarbazole

Procedia PDF Downloads 356