Search results for: rapid test activity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 16511

Search results for: rapid test activity

13721 2D Fingerprint Performance for PubChem Chemical Database

Authors: Fatimah Zawani Abdullah, Shereena Mohd Arif, Nurul Malim

Abstract:

The study of molecular similarity search in chemical database is increasingly widespread, especially in the area of drug discovery. Similarity search is an application in the field of Chemoinformatics to measure the similarity between the molecular structure which is known as the query and the structure of chemical compounds in the database. Similarity search is also one of the approaches in virtual screening which involves computational techniques and scoring the probabilities of activity. The main objective of this work is to determine the best fingerprint when compared to the other five fingerprints selected in this study using PubChem chemical dataset. This paper will discuss the similarity searching process conducted using 6 types of descriptors, which are ECFP4, ECFC4, FCFP4, FCFC4, SRECFC4 and SRFCFC4 on 15 activity classes of PubChem dataset using Tanimoto coefficient to calculate the similarity between the query structures and each of the database structure. The results suggest that ECFP4 performs the best to be used with Tanimoto coefficient in the PubChem dataset.

Keywords: 2D fingerprints, Tanimoto, PubChem, similarity searching, chemoinformatics

Procedia PDF Downloads 277
13720 Determination of the Volatile Organic Compounds, Antioxidant and Antimicrobial Properties of Microwave-Assisted Green Extracted Ficus Carica Linn Leaves

Authors: Pelin Yilmaz, Gizemnur Yildiz Uysal, Elcin Demirhan, Belma Ozbek

Abstract:

The edible fig plant, Ficus carica Linn, belongs to the Moraceae family, and the leaves are mainly considered agricultural waste after harvesting. It has been demonstrated in the literature that fig leaves contain appealing properties such as high vitamins, fiber, amino acids, organic acids, and phenolic or flavonoid content. The extraction of these valuable products has gained importance. Microwave-assisted extraction (MAE) is a method using microwave energy to heat the solvents, thereby transferring the bioactive compounds from the sample to the solvent. The main advantage of the MAE is the rapid extraction of bioactive compounds. In the present study, the MAE was applied to extract the bioactive compounds from Ficus carica L. leaves, and the effect of microwave power (180-900 W), extraction time (60-180 s), and solvent to sample amount (mL/g) (10-30) on the antioxidant property of the leaves. Then, the volatile organic component profile was determined at the specified extraction point. Additionally, antimicrobial studies were carried out to determine the minimum inhibitory concentration of the microwave-extracted leaves. As a result, according to the data obtained from the experimental studies, the highest antimicrobial properties were obtained under the process parameters such as 540 W, 180 s, and 20 mL/g concentration. The volatile organic compound profile showed that isobergapten, which belongs to the furanocoumarins family exhibiting anticancer, antioxidant, and antimicrobial activity besides promoting bone health, was the main compound. Acknowledgments: This work has been supported by Yildiz Technical University Scientific Research Projects Coordination Unit under project number FBA-2021-4409. The authors would like to acknowledge the financial support from Tubitak 1515 - Frontier R&D Laboratory Support Programme.

Keywords: Ficus carica Linn leaves, volatile organic component, GC-MS, microwave extraction, isobergapten, antimicrobial

Procedia PDF Downloads 55
13719 Photo-Degradation Black 19 Dye with Synthesized Nano-Sized ZnS

Authors: M. Tabatabaee, R. Mohebat, M. Baranian

Abstract:

Textile industries produce large volumes of colored dye effluents which are toxic and non-biodegradable. Earlier studies have shown that a wide range of organic substrates can be completely photo mineralized in the presence of photocatalysts and oxidant agents. ZnO and TiO2 are important photocatalysts with high catalytic activity that have attracted much research attention. Zinc sulfide is one of the semiconductor nanomaterials that can be used for the production of optical sensitizers, photocatalysts, electroluminescent materials, optical sensors and for solar energy conversion. The synthesis of ZnS nanoparticles has been tried by various methods and sulfide sources. Elementary sulfur powder, H2S or Na2S are used as sulfide sources for synthesis of ZnS nano particles. Recently, solar energy is has been successfully used for photocatalytic degradation of dye pollutant. Studies have shown that the use of metal oxides or sulfides with ZnO or TiO2 can significantly enhance the photocatalytic activity of them. In this research, Nano-sized zinc sulfide was synthesized successfully by a simple method using thioasetamide as sulfide source in the presence of polyethylene glycol (PEG 2000). X-ray diffraction (XRD) spectroscopy scanning electron microscope (SEM) was used to characterize the structure and morphology synthesized powder. The effect of photocatalytic activity of prepared ZnS and ZnS/ZnO, on degradation of direct Black19 under UV and sunlight irradiation was investigated. The effects of various parameters such as amount of photocatalyst, pH, initial dye concentration and irradiation time on decolorization rate were systematically investigated. Results show that more than 80% of 500 mgL-1 of dye decolorized in 60-min reaction time under UV and solar irradiation in the presence of ZnS nanoparticles. Whereas, mixed ZnS/ZnO (50%) can decolorize more than 80% of dye in the same conditions.

Keywords: zinc sulfide, nano articles, photodegradation, solar light

Procedia PDF Downloads 393
13718 Protective Effect of Levetiracetam on Aggravation of Memory Impairment in Temporal Lobe Epilepsy by Phenytoin

Authors: Asher John Mohan, Krishna K. L.

Abstract:

Objectives: (1) To assess the extent of memory impairment induced by Phenytoin (PHT) at normal and reduced dose on temporal lobe epileptic mice. (2) To evaluate the protective effect of Levetiracetam (LEV) on aggravation of memory impairment in temporal lobe epileptic mice by PHT. Materials and Methods: Albino mice of either sex (n=36) were used for the study for a period of 64 days. Convulsions were induced by intraperitoneal administration of pilocarpine 280 mg/kg on every 6th day. Radial arm maze (RAM) was employed to evaluate the memory impairment activity on every 7th day. The anticonvulsant and memory impairment activity were assessed in PHT normal and reduced doses both alone and in combination with LEV. RAM error scores and convulsive scores were the parameters considered for this study. Brain acetylcholine esterase and glutamate were determined along with histopathological studies of frontal cortex. Results: Administration of PHT for 64 days on mice has shown aggravation of memory impairment activity on temporal lobe epileptic mice. Although the reduction in PHT dose was found to decrease the degree of memory impairment the same decreased the anticonvulsant potency. The combination with LEV not only brought about the correction of impaired memory but also replaced the loss of potency due to the reduction of the dose of the antiepileptic drug employed. These findings were confirmed with enzyme and neurotransmitter levels in addition to histopathological studies. Conclusion: This study thus builds a foundation in combining a nootropic anticonvulsant with an antiepileptic drug to curb the adverse effect of memory impairment associated with temporal lobe epilepsy. However further extensive research is a must for the practical incorporation of this approach into disease therapy.

Keywords: anti-epileptic drug, Phenytoin, memory impairment, Pilocarpine

Procedia PDF Downloads 298
13717 Retrospective Study of Positive Blood Cultures Carried out in the Microbiology Department of General Hospital of Ioannina in 2017

Authors: M. Gerasimou, S. Mantzoukis, P. Christodoulou, N. Varsamis, G. Kolliopoulou, N. Zotos

Abstract:

Purpose: Microbial infection of the blood is a serious condition where bacteria invade the bloodstream and cause systemic disease. In such cases, blood cultures are performed. Blood cultures are a key diagnostic test for intensive care unit (ICU) patients. Material and method: The BacT/Alert system, which measures the production of carbon dioxide with metabolic organisms, is used. The positive result in the BacT/Alert system is followed by culture in the following selective media: Blood, Mac Conkey No 2, Chocolate, Mueller Hinton, Chapman and Sabaureaud agar. Gram staining method was used to differentiate bacterial species. The microorganisms were identified by biochemical techniques in the automated Microscan (Siemens) system and followed by a sensitivity test on the same system using the minimum inhibitory concentration MIC technique. The sensitivity test is verified by a Kirby Bauer-based test. Results: In 2017 the Laboratory of Microbiology received 3347 blood cultures. Of these, 170 came from the ICU. 116 found positive. Of these S. epidermidis was identified in 42, A. baumannii in 27, K. pneumoniae in 12 (4 of these KPC ‘Klebsiella pneumoniae carbapenemase’), S. hominis in 8, E. faecium in 7, E. faecalis in 5, P. aeruginosa in 3, C. albicans in 3, S. capitis in 2, K. oxytoca in 2, P. mirabilis in 2, E. coli in 1, S. intermidius in 1 and S. lugdunensis in 1. Conclusions: The study of epidemiological data and microbial resistance phenotypes is essential for the choice of therapeutic regimen for the early treatment and limitation of multivalent strains, while it is a crucial factor to solve diagnostic problems.

Keywords: blood culture, bloodstream, infection, intensive care unit

Procedia PDF Downloads 135
13716 In vitro Effects of Berberine on the Vitality and Oxidative Profile of Bovine Spermatozoa

Authors: Eva Tvrdá, Hana Greifová, Peter Ivanič, Norbert Lukáč

Abstract:

The aim of this study was to evaluate the dose- and time-dependent in vitro effects of berberine (BER), a natural alkaloid with numerous biological properties on bovine spermatozoa during three time periods (0 h, 2 h, 24 h). Bovine semen samples were diluted and cultivated in physiological saline solution containing 0.5% DMSO together with 200, 100, 50, 10, 5, and 1 μmol/L BER. Spermatozoa motility was assessed using the computer assisted semen analyzer. The viability of spermatozoa was assessed by the metabolic (MTT) assay, production of superoxide radicals was quantified using the nitroblue tetrazolium (NBT) test, and chemiluminescence was used to evaluate the generation of reactive oxygen species (ROS). Cell lysates were prepared and the extent of lipid peroxidation (LPO) was evaluated using the TBARS assay. The results of the movement activity showed a significant increase in the motility during long term cultivation in case of concentrations ranging between 1 and 10 μmol/L BER (P < 0.01; P < 0.001; 24 h). At the same time, supplementation of 1, 5 and 10 μmol/L BER led to a significant preservation of the cell viability (P < 0.001; 24 h). BER addition at a range of 1-50 μmol/L also provided a significantly higher protection against superoxide (P < 0.05) and ROS (P < 0.001; P < 0.01) overgeneration as well as LPO (P < 0.01; P<0.05) after a 24 h cultivation. We may suggest that supplementation of BER to bovine spermatozoa, particularly at concentrations ranging between 1 and 50 μmol/L, may offer protection to the motility, viability and oxidative status of the spermatozoa, particularly notable at 24 h.

Keywords: berberine, bulls, motility, oxidative profile, spermatozoa, viability

Procedia PDF Downloads 113
13715 The Search for the Self in Psychotherapy: Findings from Relational Theory and Neuroanatomy

Authors: Harry G. Segal

Abstract:

The idea of the “self” has been essential ever since the early modern period in western culture, especially since the development of psychotherapy, but advances in neuroscience and cognitive theory challenge traditional notions of the self. More specifically, neuroanatomists have found no location of “the self” in the brain; instead, consciousness has been posited to be a rapid combination of perception, memory, anticipation of future events, and judgment. In this paper, a theoretical model is presented to address these neuroanatomical findings and to revise the historical understanding of “selfhood” in the practice of psychotherapy.

Keywords: the self, psychotherapy, the self and the brain

Procedia PDF Downloads 89
13714 Synergistic and Antagonistic Interactions between Garlic Extracts and Metformin in Diabetes Treatment

Authors: Ikram Elsiddig, Yacouba Djamila, Amna Hamad

Abstract:

Abstract—The worldwide increasing of using herbs in form of medicine with or without prescription medications potentiates the interactions between herbal products and conventional medicines; due to more research for herb-drug interactions are needed. for a long time hyperglycemia had been treated with several medicinal plants. A. sativum, belonging to the Liliaceae family is well known for its medicinal uses in African traditional medicine, it used for treating of many human diseases mainly diabetes, high cholesterol and high blood pressure. The purpose of this study is to determine the interaction effect between A. sativum bulb extracts and metformin drug used in diabetes treatment. The in vitro and in vivo evaluation were conducted by glucose reuptake using isolated rats hemidiaphgrams tissue and by estimate glucose tolerance in glucose-loaded wistar albino rats. The results showed that, petroleum ether, chloroform and ethyl acetate extracts were found to have activity of glucose uptake in isolated rats hemidiaphgrams of 24.11 mg/g, 19.07 mg/g and 15.66 mg/g compared to metformin drug of 17 mg/g. These activity were reducded to 17.8 mg/g, 13.59 mg/g and 14.46 mg/g after combination with metformin, metformin itself reduced to 13.59 mg/g, 14.46 mg/g and 12.71 mg/g in comination with chloroform and ethyl acetate. These decrease in activity could be due to herbal–drug interaction between the extracts of A. sativum bulb and metformin drug. The interaction between A. sativum extract and metformin was also shown by in vivo study on the induced hyperglycemic rats. The glucose level after administered of 200 mg/kg was found to be increase with 47.2 % and 17.7% at first and second hour compared to the increase of blood glucose in the control group of 82.6% and76.7%.. At fourth hour the glucose level was became less than normal with 3.4% compared to control which continue to increase with 68.2%. Dose of 400 mg/kg at first hour showed increase in blood glucose of 31.5 %, at second and fourth hours the glucose level was became less than normal with decrease of 3.2 % and 30.4%. After combination the activity was found to be less than that of extract at both high and low dose, whereas, at first and second hour, the glucose level was found to be increase with 50.4% and 21.2%, at fourth hour the glucose level was became less than normal with 14%. Therefore A. sativum could be a potential source for anti-diabetic when it used alone, and it is significant important to use the garlic extract alone instead of combined with Metformin drug in diabetes- treatment.

Keywords: Antagonistic, Garlic, Metformin, Synergistic

Procedia PDF Downloads 162
13713 In-Vitro Assessment of Saponin’s Level and Hemolytic Activity of Five Medicinal Plants from Eritrea

Authors: Leah Ghebreberhan, Liya Abraham, John Issac, Atul Kaushik

Abstract:

Medicinal plants are used for various indications in Eritrea according to traditional systems of medicine. Safety concerns, however, are dubious since some medicinal plants have toxic effects indeed. The medicinal plants under study (Commicarpus pedunculosis, Steganotaenia araliaceae, Boscia angustifolia, Solanum incanum, and Calpurnia aurea) are used in the treatment of various diseases. Thus, safety studies must be performed prior to usage since they are rich in phytoconstituents like saponins. Saponns are natural glycosides with several pharmacologic activities including hemolysis. The study was done to assess the level of saponin and toxic effects (hemolysis) of medicinal plants used in folk medicine. The plant extracts were subject to phytochemical analysis, foam test, and hemolytic assay. Regarding the Fh value, Solanam incanum consisted highest Fh value (20mm), whereas Boscia angustifolia showed the lowest Fh value (10mm). The level of hemolysis of all the plant extracts ranged between 9.0 to 20.2 %. All the plant extracts were suitable for treatment with respect to saponin level since they exhibited minimal hemolytic effect against erythrocytes.

Keywords: Boscia angustifolia, Calpurnia aurea, Commicarpus pedunculosis, hemolysis, saponin, Solanum incanum, Steganotaenia araliaceae

Procedia PDF Downloads 231
13712 Comparison of Soil Test Extractants for Determination of Available Soil Phosphorus

Authors: Violina Angelova, Stefan Krustev

Abstract:

The aim of this work was to evaluate the effectiveness of different soil test extractants for the determination of available soil phosphorus in five internationally certified standard soils, sludge and clay (NCS DC 85104, NCS DC 85106, ISE 859, ISE 952, ISE 998). The certified samples were extracted with the following methods/extractants: CaCl₂, CaCl₂ and DTPA (CAT), double lactate (DL), ammonium lactate (AL), calcium acetate lactate (CAL), Olsen, Mehlich 3, Bray and Kurtz I, and Morgan, which are commonly used in soil testing laboratories. The phosphorus in soil extracts was measured colorimetrically using Spectroquant Pharo 100 spectrometer. The methods used in the study were evaluated according to the recovery of available phosphorus, facility of application and rapidity of performance. The relationships between methods are examined statistically. A good agreement of the results from different soil test was established for all certified samples. In general, the P values extracted by the nine extraction methods significantly correlated with each other. When grouping the soils according to pH, organic carbon content and clay content, weaker extraction methods showed analogous trends; also among the stronger extraction methods, common tendencies were found. Other factors influencing the extraction force of the different methods include soil: solution ratio, as well as the duration and power of shaking the samples. The mean extractable P in certified samples was found to be in the order of CaCl₂ < CAT < Morgan < Bray and Kurtz I < Olsen < CAL < DL < Mehlich 3 < AL. Although the nine methods extracted different amounts of P from the certified samples, values of P extracted by the different methods were strongly correlated among themselves. Acknowledgment: The financial support by the Bulgarian National Science Fund Projects DFNI Н04/9 and DFNI Н06/21 are greatly appreciated.

Keywords: available soil phosphorus, certified samples, determination, soil test extractants

Procedia PDF Downloads 134
13711 Telomerase, a Biomarker in Oral Cancer Cell Proliferation and Tool for Its Prevention at Initial Stage

Authors: Shaista Suhail

Abstract:

As cancer populations is increasing sharply, the incidence of oral squamous cell carcinoma (OSCC) has also been expected to increase. Oral carcinogenesis is a highly complex, multistep process which involves accumulation of genetic alterations that lead to the induction of proteins promoting cell growth (encoded by oncogenes), increased enzymatic (telomerase) activity promoting cancer cell proliferation. The global increase in frequency and mortality, as well as the poor prognosis of oral squamous cell carcinoma, has intensified current research efforts in the field of prevention and early detection of this disease. The advances in the understanding of the molecular basis of oral cancer should help in the identification of new markers. The study of the carcinogenic process of the oral cancer, including continued analysis of new genetic alterations, along with their temporal sequencing during initiation, promotion and progression, will allow us to identify new diagnostic and prognostic factors, which will provide a promising basis for the application of more rational and efficient treatments. Telomerase activity has been readily found in most cancer biopsies, in premalignant lesions or germ cells. Activity of telomerase is generally absent in normal tissues. It is known to be induced upon immortalization or malignant transformation of human cells such as in oral cancer cells. Maintenance of telomeres plays an essential role during transformation of precancer to malignant stage. Mammalian telomeres, a specialized nucleoprotein structures are composed of large conctamers of the guanine-rich sequence 5_-TTAGGG-3_. The roles of telomeres in regulating both stability of genome and replicative immortality seem to contribute in essential ways in cancer initiation and progression. It is concluded that activity of telomerase can be used as a biomarker for diagnosis of malignant oral cancer and a target for inactivation in chemotherapy or gene therapy. Its expression will also prove to be an important diagnostic tool as well as a novel target for cancer therapy. The activation of telomerase may be an important step in tumorgenesis which can be controlled by inactivating its activity during chemotherapy. The expression and activity of telomerase are indispensable for cancer development. There are no drugs which can effect extremely to treat oral cancers. There is a general call for new emerging drugs or methods that are highly effective towards cancer treatment, possess low toxicity, and have a minor environment impact. Some novel natural products also offer opportunities for innovation in drug discovery. Natural compounds isolated from medicinal plants, as rich sources of novel anticancer drugs, have been of increasing interest with some enzyme (telomerase) blockage property. The alarming reports of cancer cases increase the awareness amongst the clinicians and researchers pertaining to investigate newer drug with low toxicity.

Keywords: oral carcinoma, telomere, telomerase, blockage

Procedia PDF Downloads 156
13710 Effect of Sedimentation on Torque Transmission in the Larger Radius Magnetorheological Clutch

Authors: Manish Kumar Thakur, Chiranjit Sarkar

Abstract:

Sedimentation of magnetorheological (MR) fluid affects its working. MR fluid is a smart fluid that has unique qualities such as quick responsiveness and easy controllability. It is used in the MR damper, MR brake, and MR clutch. In this work effect of sedimentation on torque transmission in the shear mode operated MR clutch is investigated. A test rig is developed to test the impact of sedimentation on torque transmission in the MR clutch. Torque transmission capability of MR clutch has been measured under two conditions to confirm the result of sedimentation. The first experiment is done just after filling and the other after one week. It has been observed that transmission torque is decreased after sedimentation. Hence sedimentation affects the working of the MR clutch.

Keywords: clutch, magnetorheological fluid, sedimentation, torque

Procedia PDF Downloads 170
13709 Alumina Supported Copper-manganese Catalysts for Combustion of Exhaust Gases: Catalysts Characterization

Authors: Krasimir I. Ivanov, Elitsa N. Kolentsova, Dimitar Y. Dimitrov, Georgi V. Avdeev, Tatyana T. Tabakova

Abstract:

In recent research copper and manganese systems were found to be the most active in CO and organic compounds oxidation among the base catalysts. The mixed copper manganese oxide has been widely studied in oxidation reactions because of their higher activity at low temperatures in comparison with single oxide catalysts. The results showed that the formation of spinel CuxMn3−xO4 in the oxidized catalyst is responsible for the activity even at room temperature. That is why most of the investigations are focused on the hopcalite catalyst (CuMn2O4) as the best copper-manganese catalyst. Now it’s known that this is true only for CO oxidation, but not for mixture of CO and VOCs. The purpose of this study is to investigate the alumina supported copper-manganese catalysts with different Cu/Mn molar ratio in terms of oxidation of CO, methanol and dimethyl ether. The catalysts were prepared by impregnation of γ-Al2O3 with copper and manganese nitrates and the catalytic activity measurements were carried out in continuous flow equipment with a four-channel isothermal stainless steel reactor. Gas mixtures on the input and output of the reactor were analyzed with a gas chromatograph, equipped with FID and TCD detectors. The texture characteristics were determined by low-temperature (- 196 oС) nitrogen adsorption in a Quantachrome Instruments NOVA 1200e (USA) specific surface area&pore analyzer. Thermal, XRD and TPR analyses were performed. It was established that the active component of the mixed Cu-Mn/γ–alumina catalysts strongly depends on the Cu/Mn molar ratio. Highly active alumina supported Cu-Mn catalysts for CO, methanol and DME oxidation were synthesized. While the hopcalite is the best catalyst for CO oxidation, the best compromise for simultaneous oxidation of all components is the catalyst with Cu/Mn molar ratio 1:5.

Keywords: supported copper-manganese catalysts, CO, VOCs oxidation, combustion of exhaust gases

Procedia PDF Downloads 273
13708 Estimation of Aquifer Properties Using Pumping Tests: Case Study of Pydibhimavaram Industrial Area, Srikakulam, India

Authors: G. Venkata Rao, P. Kalpana, R. Srinivasa Rao

Abstract:

Adequate and reliable estimates of aquifer parameters are of utmost importance for proper management of vital groundwater resources. At present scenario the ground water is polluted because of industrial waste disposed over the land and the contaminants are transported in the aquifer from one area to another area which is depending on the characteristics of the aquifer and contaminants. To know the contaminant transport, the accurate estimation of aquifer properties is highly needed. Conventionally, these properties are estimated through pumping tests carried out on water wells. The occurrence and movement of ground water in the aquifer are characteristically defined by the aquifer parameters. The pumping (aquifer) test is the standard technique for estimating various hydraulic properties of aquifer systems, viz, transmissivity (T), hydraulic conductivity (K), storage coefficient (S) etc., for which the graphical method is widely used. The study area for conducting pumping test is Pydibheemavaram Industrial area near the coastal belt of Srikulam, AP, India. The main objective of the present work is to estimate the aquifer properties for developing contaminant transport model for the study area.

Keywords: aquifer, contaminant transport, hydraulic conductivity, industrial waste, pumping test

Procedia PDF Downloads 428
13707 Quality of Life Assessment across the Cancer Continuum: Understanding the Role of an Exercise Rehabilitation Programme

Authors: Bernat-Carles Serdà Ferrer, Arantza Del Valle Gómez

Abstract:

The Quality of Life (QoL) paradigm is multidimensional, dynamic and modular and its definition differs across the cancer continuum. The challenge in the interpretation of QoL data in clinical research is that QoL is influenced by psychological phenomena such as adaptation to illness. This research aims to obtain a valid and sensitive assessment of QoL change over the continuum disease, and to evaluate a rehabilitation programme aimed at inverting the observed decrease in QoL when patients return to daily living activities. The sample comprised 66 men. Patients were first assessed to establish a baseline (P1-diagnosis). This was followed by a post-test (P2-discharge) and a then-test measurement (P3-retrospective evaluation) and after returning home patients were randomized in experimental and control groups. The experimental group attended a rehabilitation programme over 24 weeks (P4). Results show that from baseline to post-test, QoL decreased significantly. The recalibration then-test confirmed a low QoL in all periods evaluated. Significant differences between the experimental and control groups prove the positive effect of the Exercise Rehabilitation Programme (ERP) on QoL. Understanding the real dynamic of QoL over time would help to adapt rehabilitation programmes by improving sensitivity and efficacy and provide professionals with a more accurate perception of the impact of treatment and side effects on patients’ QoL. Our results underline the importance of changing the approach adopted by health professionals towards one of watchful waiting on patients’ QoL until their complete recovery in daily life.

Keywords: exercise, prostate cancer, quality of life, rehabilitation programme, response shift

Procedia PDF Downloads 151
13706 Effect of Microfiltration on the Composition and Ripening of Iranian Fetta Cheese

Authors: M. Dezyani, R. Ezzati belvirdi, M. Shakerian, H. Mirzaei

Abstract:

The effect of Microfiltration (MF) on proteolysis, hardness, and flavor of Feta cheese during 6 mo of aging was determined. Raw skim milk was microfiltered two-fold in two cheese making trials. In trial 1, four vats of cheese were made in 1 d using unconcentrated milk (1X), 1.26X, 1.51X, and 1.82X Concentration Factors (CF). Casein-(CN)-to-fat ratio was constant among treatments. Proteolysis during cheese aging decreased with increasing CF due to either limitation of substrate availability for chymosin due to low moisture in the nonfat substance (MNFS), inhibition of chymosin activity by high molecular weight milk serum proteins, such as α2-macroglobulin, retained in the cheese or low residual chymosin in the cheese. Hardness of fresh cheese increased, and cheese flavor intensity decreased with increasing CF. In trial 2, the 1X and 1.8X CF were compared directly. Changes made in the cheese making procedure for the 1.8X CF (more chymosin and less cooking) increased the MNFS and made proteolysis during aging more comparable for the 1X and 1.8X cheeses. The significant difference in cheese hardness due to CF in trial 1 was eliminated in trial 2. In a triangle test, panelists could not differentiate between the 1X and 1.8X cheeses. Therefore, increasing chymosin and making the composition of the two cheeses more similar allowed production of aged Fetta cheese from milk concentrated up to 1.8X by MF that was not perceived as different from aged feta cheese produced without MF.

Keywords: feta cheese, microfiltration, concentration factor, proteolysis

Procedia PDF Downloads 399
13705 High Performance Wood Shear Walls and Dissipative Anchors for Damage Limitation

Authors: Vera Wilden, Benno Hoffmeister, Georgios Balaskas, Lukas Rauber, Burkhard Walter

Abstract:

Light-weight timber frame elements represent an efficient structural solution for wooden multistory buildings. The wall elements of such buildings – which act as shear diaphragms- provide lateral stiffness and resistance to wind and seismic loads. The tendency towards multi-story structures leads to challenges regarding the prediction of stiffness, strength and ductility of the buildings. Lightweight timber frame elements are built up of several structural parts (sheeting, fasteners, frame, support and anchorages); each of them contributing to the dynamic response of the structure. This contribution describes the experimental and numerical investigation and development of enhanced lightweight timber frame buildings. These developments comprise high-performance timber frame walls with the variable arrangements of sheathing planes and dissipative anchors at the base of the timber buildings, which reduce damages to the timber structure and can be exchanged after significant earthquakes. In order to prove the performance of the developed elements in the context of a real building a full-scale two-story building core was designed and erected in the laboratory and tested experimentally for its seismic performance. The results of the tests and a comparison of the test results to the predicted behavior are presented. Observation during the test also reveals some aspects of the design and details which need to consider in the application of the timber walls in the context of the complete building.

Keywords: dissipative anchoring, full scale test, push-over-test, wood shear walls

Procedia PDF Downloads 223
13704 Antibacterial Activity of Nisin: Comparison the Role of Free and Encapsulated Nisin to Control Staphylococcus Aureus Inoculated in Minced Beef

Authors: Zh. Ghasemi, S. Nouri Saeedlou, A. Ghasemi, SL. Nasiri, P. Ayremlou, P. Mahasti

Abstract:

The use of nisin is successfully used as antibacterial agent in various food products. Although the conclusions of the previous studies were that nisin is not very effective in meat environments. The reduced antimicrobial efficacy of nisin when applied in food has been frequently observed. The aim of this study is to evaluate the potential of free and encapsulated nisin to inhibit the growth of staphylococcus aureus in minced beef. The minimum inhibitory concentration (MIC) of nisin is determined against S. aureus using the agar dilution method. Nisin is encapsulated by spray drying, and encapsulation efficiency, mass yield and total solids content values are 47.79%, 61%, and 96.41 respectively. The study in vitro release kinetics shows highest release of nisin from zein capsules is obtained after 72 hour. This work shows that an appropriate delivery system is necessary to obtain desirable effect of nisin in meat and meat product.

Keywords: nisin, encapsulation, Staphylococcus aureus, minced beef, antibacterial activity

Procedia PDF Downloads 279
13703 The Effects of Country of Manufacture and Country of Brand on Purchase Intention: The Moderating Role of Brand Experience

Authors: Natinee Thanajaro

Abstract:

In the past few decades, international research on the country of origin of products has garnered significant interest, particularly in investigating the effects of consumers’ evaluation and perception. As globalization and market competition rise, international firms are seeking ways to control their labour costs and minimise taxes. Many products are outsourced and manufactured in countries with cheap labour. Consequently, the proliferation of ‘bi-national’ products has increased, raising important questions related to consumers’ perception. Moreover, the rapid growth in emerging markets, especially in Asia, has made these countries attractive options for international brands. Therefore, studying the country of origin allows firms and researchers to understand how customers perceive such information regarding the country of manufacture and the country of the brand. This study aims to investigate the influence of the country of manufacture (COM) and country of brand (COB) on Thai consumers’ perception of the brand. In addition, it embraces a different perspective on brand experience as a moderating factor. A sample of 403 Thai respondents was collected through face-to-face survey questionnaires in central Bangkok. This research employs an experiment using a factorial design to test the hypotheses. SPSS statistics software was adopted to analyse and validate the reliability of the testing of the constructs and model hypotheses. The results of this research show that the respondents positively respond to the COB more than the COM, and brand experience plays a moderating role in this research. This research provides a significant contribution to the existing literature and managerial practicality by using multi-dimensional information on the country and analyses the relationships between these dimensions.

Keywords: brand experience, country of brand, country of manufacture, purchase intention

Procedia PDF Downloads 115
13702 Reducing Power Consumption in Network on Chip Using Scramble Techniques

Authors: Vinayaga Jagadessh Raja, R. Ganesan, S. Ramesh Kumar

Abstract:

An ever more significant fraction of the overall power dissipation of a network-on-chip (NoC) based system on- chip (SoC) is due to the interconnection scheme. In information, as equipment shrinks, the power contributes of NoC links starts to compete with that of NoC routers. In this paper, we propose the use of clock gating in the data encoding techniques as a viable way to reduce both power dissipation and time consumption of NoC links. The projected scramble scheme exploits the wormhole switching techniques. That is, flits are scramble by the network interface (NI) before they are injected in the network and are decoded by the target NI. This makes the scheme transparent to the underlying network since the encoder and decoder logic is integrated in the NI and no modification of the routers structural design is required. We review the projected scramble scheme on a set of representative data streams (both synthetic and extracted from real applications) showing that it is possible to reduce the power contribution of both the self-switching activity and the coupling switching activity in inter-routers links.

Keywords: Xilinx 12.1, power consumption, Encoder, NOC

Procedia PDF Downloads 388
13701 Measuring the Effect of Continuous Performance Test-3 Administration on Regional Cerebral Blood Flow with Single-Photon Emission Computed Tomography in Adult ADHD

Authors: Claire Stafford, Charles Golden, Daniel Amen, Kristen Willeumier

Abstract:

The aim of this study is to investigate the effect of the administration of the Conners Continuous Performance Test (CPT-3) on cerebral blood flow (CBF) in adults with ADHD. The data for this study was derived from a large SPECT database. Participants in the ADHD group (n=81, Mage=37.97) were similar to those in the healthy control group (n=8503, Mage=41.86). All participants were assessed for cerebral blood flow levels before and after CPT-3 administration. Both age and gender were considered covariates. Multiple 2-by-2 ANCOVAs with repeated measures were conducted with sphericity assumed. The main effects of CPT-3 administration on CBF levels were significant in the left and right side of the frontal and occipital, and right temporal lobe. The main effects of ADHD diagnosis were significant in all brain areas assessed. The interaction between CPT-3 administration and ADHD diagnosis was significant in the left and right side of the limbic system, basal ganglia, the frontal lobe, and occipital lobe. Post hoc tests with a Bonferroni adjustment revealed that CBF levels increased following CPT-3 administration but less so in the ADHD group. Individuals had higher levels of CBF following the administration of CPT-3. Due to a significant interaction, we can infer that ADHD diagnosis changes the effect of CPT-3 administration on CBF levels. This is consistent with our hypothesis considering that CPT-3 is a test of sustained attention, a common challenge for children with ADHD. The aforementioned interaction was not found to be significant in the parietal lobe. This may be due to the nature of CPT- 3 which does not require an integration of sensory information.

Keywords: SPECT, ADHD, conners continuous performance test, cerebral blood flow

Procedia PDF Downloads 88
13700 Calibration of Contact Model Parameters and Analysis of Microscopic Behaviors of Cuxhaven Sand Using The Discrete Element Method

Authors: Anjali Uday, Yuting Wang, Andres Alfonso Pena Olare

Abstract:

The Discrete Element Method is a promising approach to modeling microscopic behaviors of granular materials. The quality of the simulations however depends on the model parameters utilized. The present study focuses on calibration and validation of the discrete element parameters for Cuxhaven sand based on the experimental data from triaxial and oedometer tests. A sensitivity analysis was conducted during the sample preparation stage and the shear stage of the triaxial tests. The influence of parameters like rolling resistance, inter-particle friction coefficient, confining pressure and effective modulus were investigated on the void ratio of the sample generated. During the shear stage, the effect of parameters like inter-particle friction coefficient, effective modulus, rolling resistance friction coefficient and normal-to-shear stiffness ratio are examined. The calibration of the parameters is carried out such that the simulations reproduce the macro mechanical characteristics like dilation angle, peak stress, and stiffness. The above-mentioned calibrated parameters are then validated by simulating an oedometer test on the sand. The oedometer test results are in good agreement with experiments, which proves the suitability of the calibrated parameters. In the next step, the calibrated and validated model parameters are applied to forecast the micromechanical behavior including the evolution of contact force chains, buckling of columns of particles, observation of non-coaxiality, and sample inhomogeneity during a simple shear test. The evolution of contact force chains vividly shows the distribution, and alignment of strong contact forces. The changes in coordination number are in good agreement with the volumetric strain exhibited during the simple shear test. The vertical inhomogeneity of void ratios is documented throughout the shearing phase, which shows looser structures in the top and bottom layers. Buckling of columns is not observed due to the small rolling resistance coefficient adopted for simulations. The non-coaxiality of principal stress and strain rate is also well captured. Thus the micromechanical behaviors are well described using the calibrated and validated material parameters.

Keywords: discrete element model, parameter calibration, triaxial test, oedometer test, simple shear test

Procedia PDF Downloads 106
13699 The Effect of Online Self-Assessment Diaries on Academic Achievement

Authors: Zi Yan

Abstract:

The pedagogical value of self-assessment is widely recognized. However, identifying effective methods to help students develop productive SA practices poses a significant challenge. Since most students do not acquire self-assessment skills intuitively, they need instruction and guidance. This study is a randomized controlled trial aiming to test the effect of online self-assessment diaries on students’ achievement scores compared to a control group. Two groups of secondary school students (N=59), recruited through convenience sampling, participated in the study. The two groups were randomly designated to one of two conditions: control (n = 31) and online self-assessment diary (n = 28). The participants completed a curriculum-specific pre-test and a baseline survey on the first week of the 10-week study, as well as completed a post-test and survey by the tenth week. The results showed that the SA diary intervention had a significantly positive effect on post-intervention language learning scores after controlling for baseline scores. The findings highlight the potential of self-assessment to enhance educational outcomes, emphasizing its significant implications for educational policies that promote the integration of SA strategies into pedagogical practices.

Keywords: self-assessment, online diary, academic achievement, experimenal study

Procedia PDF Downloads 33
13698 Interactive Lecture Demonstration and Inquiry-Based Instruction in Addressing Students' Misconceptions in Electric Circuits

Authors: Mark Anthony Casimiro, Ivan Culaba, Cornelia Soto

Abstract:

Misconceptions are the wrong concepts understood by the students which may come up based on what they experience and observe around their environment. This seemed to hinder students’ learning. In this study, six different misconceptions were determined by the researcher from the previous researches. Teachers play a vital role in the classroom. The use of appropriate strategies can contribute a lot in the success of teaching and learning Physics. The current study aimed to compare two strategies- Interactive Lecture Demonstration (ILD) and Inquiry-Based Instruction (IBI) in addressing students’ misconceptions in electric circuits. These two strategies are both interactive learning activities and student-centered. In ILD, the teacher demonstrates the activity and the students have their predictions while in IBI, students perform the experiments. The study used the mixed method in which quantitative and qualitative researches were combined. The main data of this study were the test scores of the students from the pretest and posttest. Likewise, an interview with the teacher, observer and students was done before, during and after the execution of the activities. Determining and Interpreting Resistive Electric Circuits Test version 2 (DIRECT v.2) was the instrument used in the study. Two sections of Grade 9 students from Kalumpang National High School were the respondents of the study. The two strategies were executed to each section; one class was assigned as the ILD group and the other class was the IBI group. The Physics teacher of the said school was the one who taught and executed the activities. The researcher taught the teacher the steps in doing the two strategies. The Department of Education level of proficiency in the Philippines was adopted in scoring and interpretation. The students’ level of proficiency was used in assessing students’ knowledge on electric circuits. The pretest result of the two groups had a p-value of 0.493 which was greater than the level of significance 0.05 (p >0.05) and it implied that the students’ level of understanding in the topic was the same before the execution of the strategies. The posttest results showed that the p-value (0.228) obtained was greater than the level of significance which is 0.05 (p> 0.05). This implied that the students from the ILD and IBI groups had the same level of understanding after the execution of the two strategies. This could be inferred that either of the two strategies- Interactive Lecture Demonstration and Inquiry-Based Instruction could be used in addressing students’ misconception in electric circuit as both had similar effect on the students’ level of understanding in the topic. The result of this study may greatly help teachers, administration, school heads think of appropriate strategies that can address misconceptions depending on the availability of their materials of their school.

Keywords: inquiry- based instruction, interactive lecture demonstration, misconceptions, mixed method

Procedia PDF Downloads 206
13697 Comparative Study of Outcomes of Nonfixation of Mesh versus Fixation in Laparoscopic Total Extra Peritoneal (TEP) Repair of Inguinal Hernia: A Prospective Randomized Controlled Trial

Authors: Raman Sharma, S. K. Jain

Abstract:

Aims and Objectives: Fixation of the mesh during laparoscopic total extraperitoneal (TEP) repair of inguinal hernia is thought to be necessary to prevent recurrence. However, mesh fixation may increase surgical complications and postoperative pain. Our objective was to compare the outcomes of nonfixation with fixation of polypropylene mesh by metal tacks during TEP repair of inguinal hernia. Methods: Forty patients aged 18 to72 years with inguinal hernia were included who underwent laparoscopic TEP repair of inguinal hernia with (n=20) or without (n=20) fixation of the mesh. The outcomes were operative duration, postoperative pain score, cost, in-hospital stay, time to return to normal activity, and complications. Results: Patients in whom the mesh was not fixed had shorter mean operating time (p < 0.05). We found no difference between groups in the postoperative pain score, incidence of recurrence, in-hospital stay, time to return to normal activity and complications (P > 0.05). Moreover, a net cost savings was realized for each hernia repair performed without stapled mesh. Conclusions: TEP repair without mesh fixation resulted in the shorter operating time and lower operative cost with no difference between groups in the postoperative pain score, incidence of recurrence, in-hospital stay, time to return to normal activity and complications. All this contribute to make TEP repair without mesh fixation a better choice for repair of uncomplicated inguinal hernia, especially in developing nations with scarce resources.

Keywords: postoperative pain score, inguinal hernia, nonfixation of mesh, total extra peritoneal (TEP)

Procedia PDF Downloads 323
13696 Evaluation of Phytochemical and Antidiarrhoeal Activity of Butanol Fraction of Terminalia avicennioides Leaf in Swiss Albino Rats

Authors: Fatima Mohammed Musa, J. B. Ameh, S. A. Ado, O. S. Olonitola

Abstract:

The study was undertaken to evaluate the phytochemical constituents of extracts of Terminalia avicennioides leaf and the antidiarrhoeal effect of n-butanol fraction of the leaf extract in Swiss albino rats infected with Salmonella Typhimurium and Escherichia coli. Ethanol crude extract of Terminalia avicennioides leaf was dissolved in 1.5 liters of sterile distilled water. The extract solution was partitioned with 250 ml each of chloroform, ethyl acetate and n-butanol solvents (1:1v/v) to obtain soluble fractions from the extract. The leaf extract and its fractions were screened for the presence of phytocompounds using standard analytical methods. The antidirrhoeal activity of n-butanol fraction was evaluated in Swiss albino rats using standard methods. The results of phytochemical screening of extract of Terminalia avicennioides leaf and its fractions, revealed the presence of carbohydrates, alkaloids, tannins, flavonoids, saponins, steroids, triterpens, glycosides and phenols. The results of in vivo activity showed that 60 % of each group of rats infected with 2.0 x 108 cfu/ml viable cells of S. Typhimurium and 2.0 x109 cfu/ml viable cells of E. coli manifested the symptoms of diarrhoea, 72 hours after the rats were challenged with bacteria. Other symptoms observed among the infected animals included, loss of appetite, loss of weight, general body weakness and 40 % mortality in S. Typhimurium infected non treated group of rats. Similarly, 60 %, and 20 % mortality was observed among E. coli infected none treated and E. coli infected antibiotic (metronidazole) treated groups of rats respectively. However, there was a reduction in the number of infected rats defecating watery stools over time among all the infected rats that were treated with n-butanol fraction of the leaf extract and mortality was also not observed in the group, indicating high efficacy of n-butanol fraction of T. avicennioides leaf. The results also indicated that n-butanol can be used as alternative source of antidiarrhoeal agent in the treatment of diarrhoea caused by Salmonella Typhimurium and Escherichia coli. In the light of this, there is a need for further research on the mechanism of action of the candidate fraction of T. avicennioides leaf which could be responsible for the observed in vivo antibacterial activity.

Keywords: antidirrhoeal effect, phytochemical constituents, swiss albino rats, terminalia avicennioides

Procedia PDF Downloads 360
13695 Development of 4-Allylpyrocatechol Loaded Self-Nanoemulsifying Drug Delivery System for Enhancing Water Solubility and Antibacterial Activity against Oral Pathogenic Bacteria

Authors: Pimpak Phumat, Sakornrat Khongkhunthian, Thomas Rades, Anette Müllertz, Siriporn Okonogi

Abstract:

Self-nanoemulsifying drug delivery systems (SNEDDS) containing 4-allylpyrocatechol (AP) extracted from Piper betle were developed to enhance water solubility of AP by using modeling and design (MODDE) program. The amount of AP in each SNEDDS formulation was determined by using high-performance liquid chromatography. The formulation consisted of 20% Miglyol®812N, 40 % Kolliphor®RH40, 30 % Maisine®35-1 and 10 % ethanol was found to be the best SNEDDS that provided the highest loading capacity of AP. (141.48±15.64 mg/g SNEDDS). The system also showed miscibility with water. The particle shape and size of the AP-SNEDDS after dispersing in water was investigated by using a transmission electron microscope and photon correlation spectrophotometer, respectively. The results showed that they were a spherical shape, having a particle size of 34.27 ± 1.14 nm with a narrow size distribution of 0.17 ± 0.04. The particles showed negative zeta potential with a value of -21.66 ± 2.09 mV. Antibacterial activity of AP-SNEDDS containing 1.5 mg/mL of AP was investigated against Streptococcus intermedius. The effect of this system on S. intermedius cells was observed by a scanning electron microscope (SEM). The results from SEM revealed that the bacterial cells were obviously destroyed. Killing kinetic study of AP-SNEDDS was carried out. It was found that the killing rate of AP-SNEDDS against S. intermedius was dose-dependent and the bacterial reduction was 79.86 ± 0.45 % within 30 min. In comparison with chlorhexidine (CHX), AP-SNEDDS showed similar antibacterial effects against S. intermedius. It is concluded that SNEDDS is a potential system for enhancing water solubility of AP. The antibacterial study reveals that AP-SNEDDS can be a promising system to treat bacterial infection caused by S. intermedius.

Keywords: SNEDDS, 4-allylpyrocathecol, solubility, antibacterial activity, Streptococcus intermedius

Procedia PDF Downloads 101
13694 Assessment of the Psychoemotional State and Quality of Life at Women Teachers of the Senior Age Group

Authors: Meruyert Burumbayeva, Aiman Mussina, Gulnoza Aldabekova, Aiymtory Abildaeva, Gulshat Yerdenova, Aigul Kairgeldina

Abstract:

this article introduces results of a research which purpose is evaluation the quality of life, the psychophysiological status, expressiveness of uneasiness at women teachers of the senior age group. At a research of quality of life of teachers the lowest values have been received from the indicators of the general state of health, vital activity, role emotional functioning and mental health. Every second woman-teacher noted high personal uneasiness; every third woman-teacher noted moderate situational uneasiness, confirming the existence of a professional stress. Revealed the interrelation between alarming conditions and a decrease in a mental component of health. Moreover, there was revealed exhaustion signs at low activity values that indicate a high tension of labor process.

Keywords: expressiveness of uneasiness, quality of life, psychophysiological status, component of health

Procedia PDF Downloads 274
13693 Accelerator Mass Spectrometry Analysis of Isotopes of Plutonium in PM₂.₅

Authors: C. G. Mendez-Garcia, E. T. Romero-Guzman, H. Hernandez-Mendoza, C. Solis, E. Chavez-Lomeli, E. Chamizo, R. Garcia-Tenorio

Abstract:

Plutonium is present in different concentrations in the environment and biological samples related to nuclear weapons testing, nuclear waste recycling and accidental discharges of nuclear plants. This radioisotope is considered the most radiotoxic substance, particularly when it enters the human body through inhalation of powders insoluble or aerosols. This is the main reason of the determination of the concentration of this radioisotope in the atmosphere. Besides that, the isotopic ratio of ²⁴⁰Pu/²³⁹Pu provides information about the origin of the source. PM₂.₅ sampling was carried out in the Metropolitan Zone of the Valley of Mexico (MZVM) from February 18th to March 17th in 2015 on quartz filter. There have been significant developments recently due to the establishment of new methods for sample preparation and accurate measurement to detect ultra trace levels as the plutonium is found in the environment. The accelerator mass spectrometry (AMS) is a technique that allows measuring levels of detection around of femtograms (10-15 g). The AMS determinations include the chemical isolation of Pu. The Pu separation involved an acidic digestion and a radiochemical purification using an anion exchange resin. Finally, the source is prepared, when Pu is pressed in the corresponding cathodes. According to the author's knowledge on these aerosols showed variations on the ²³⁵U/²³⁸U ratio of the natural value, suggesting that could be an anthropogenic source altering it. The determination of the concentration of the isotopes of Pu can be a useful tool in order the clarify this presence in the atmosphere. The first results showed a mean value of activity concentration of ²³⁹Pu of 280 nBq m⁻³ thus the ²⁴⁰Pu/²³⁹Pu was 0.025 corresponding to the weapon production source; these results corroborate that there is an anthropogenic influence that is increasing the concentration of radioactive material in PM₂.₅. According to the author's knowledge in Total Suspended Particles (TSP) have been reported activity concentrations of ²³⁹⁺²⁴⁰Pu around few tens of nBq m⁻³ and 0.17 of ²⁴⁰Pu/²³⁹Pu ratios. The preliminary results in MZVM show high activity concentrations of isotopes of Pu (40 and 700 nBq m⁻³) and low ²⁴⁰Pu/²³⁹Pu ratio than reported. These results are in the order of the activity concentrations of Pu in weapons-grade of high purity.

Keywords: aerosols, fallout, mass spectrometry, radiochemistry, tracer, ²⁴⁰Pu/²³⁹Pu ratio

Procedia PDF Downloads 154
13692 Comparison of Johnson-Cook and Barlat Material Model for 316L Stainless Steel

Authors: Yiğit Gürler, İbrahim Şimşek, Müge Savaştaer, Ayberk Karakuş, Alper Taşdemirci

Abstract:

316L steel is frequently used in the industry due to its easy formability and accessibility in sheet metal forming processes. Numerical and experimental studies are frequently encountered in the literature to examine the mechanical behavior of 316L stainless steel during the forming process. 316L stainless steel is the most common material used in the production of plate heat exchangers and plate heat exchangers are produced by plastic deformation of the stainless steel. The motivation in this study is to determine the appropriate material model during the simulation of the sheet metal forming process. For this reason, two different material models were examined and Ls-Dyna material cards were created using material test data. These are MAT133_BARLAT_YLD2000 and MAT093_SIMPLIFIED_JOHNSON_COOK. In order to compare results of the tensile test & hydraulic bulge test performed both numerically and experimentally. The obtained results were evaluated comparatively and the most suitable material model was selected for the forming simulation. In future studies, this material model will be used in the numerical modeling of the sheet metal forming process.

Keywords: 316L, mechanical characterization, metal forming, Ls-Dyna

Procedia PDF Downloads 305