Search results for: maximum pressure
Commenced in January 2007
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Paper Count: 7656

Search results for: maximum pressure

696 Microbiological Profile of UTI along with Their Antibiotic Sensitivity Pattern with Special Reference to Nitrofurantoin

Authors: Rupinder Bakshi, Geeta Walia, Anita Gupta

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Introduction: Urinary tract infections (UTI) are considered to be one of the most common bacterial infections with an estimated annual global incidence of 150 million. Antimicrobial drug resistance is one of the major threats due to widespread usage of uncontrolled antibiotics. Materials and Methods: A total number of 9149 urine samples were collected from R.H Patiala and processed in the Department of Microbiology G.M.C Patiala. Urine samples were inoculated on MacConkey’s and blood agar plates by using calibrated loop delivering 0.001 ml of sample and incubated at 37 °C for 24 hrs. The organisms were identified by colony characters, gram’s staining and biochemical reactions. Antimicrobial susceptibility of the isolates was determined against various antimicrobial agents (Hi – Media Mumbai India) by Kirby-Bauer disk diffusion method on Muller Hinton agar plates. Results: Maximum patients were in the age group of 21-30 yrs followed by 31-40 yrs. Males (34%) are less prone to urinary tract infections than females (66%). Out of 9149 urine sample, the culture was positive in 25% (2290) samples. Esch. coli was the most common isolate 60.3% (n = 1378) followed by Klebsiella pneumoniae 13.5% (n = 310), Proteus spp. 9% (n = 209), Staphylococcus aureus 7.6 % (n = 173), Pseudomonas aeruginosa 3.7% (n = 84), Citrobacter spp. 3.1 % (70), Staphylococcus saprophyticus 1.8 % (n = 142), Enterococcus faecalis 0.8%(n=19) and Acinetobacter spp. 0.2%(n=5). Gram negative isolates showed higher sensitivity towards, Piperacillin +Tazobactum (67%), Amikacin (80%), Nitrofurantoin (82%), Aztreonam (100%), Imipenem (100%) and Meropenam (100%) while gram positive showed good response towards Netilmicin (69%), Nitrofurantoin (79%), Linezolid (98%), Vancomycin (100%) and Teicoplanin (100%). 465 (23%) isolates were resistant to Penicillins, 1st generation and 2nd generation Cehalosporins which were further tested by double disk approximation test and combined disk method for ESBL production. Out of 465 isolates, 375 were ESBLs consisting of n 264 (70.6%) Esch.coli and 111 (29.4%) Klebsiella pneumoniae. Susceptibility of ESBL producers to Imipenem, Nitrofurantoin and Amikacin were found to be 100%, 76%, and 75% respectively. Conclusion: Uropathogens are increasingly showing resistance to many antibiotics making empiric management of outpatients UTIs challenging. Ampicillin, Cotrimoxazole, and Ciprofloxacin should not be used in empiric treatment. Nitrofurantoin could be used in lower urinary tract infection. Knowledge of uropathogens and their antimicrobial susceptibility pattern in a geographical region will help inappropriate and judicious antibiotic usage in a health care setup.

Keywords: Urinary Tract Infection, UTI, antibiotic susceptibility pattern, ESBL

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695 Sorghum Polyphenols Encapsulated by Spray Drying, Using Modified Starches as Wall Materials

Authors: Adriana Garcia G., Alberto A. Escobar P., Amira D. Calvo L., Gabriel Lizama U., Alejandro Zepeda P., Fernando Martínez B., Susana Rincón A.

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Different studies have recently been focused on the use of antioxidants such as polyphenols because of to its anticarcinogenic capacity. However, these compounds are highly sensible to environmental factors such as light and heat, so lose its long-term stability, besides possess an astringent and bitter taste. Nevertheless, the polyphenols can be protected by microcapsule formulation. In this sense, a rich source of polyphenols is sorghum, besides presenting a high starch content. Due to the above, the aim of this work was to obtain modified starches from sorghum by extrusion to encapsulate polyphenols the sorghum by spray drying. Polyphenols were extracted by ethanol solution from sorghum (Pajarero/red) and determined by the method of Folin-Ciocalteu, obtaining GAE at 30 mg/g. Moreover, was extracted starch of sorghum (Sinaloense/white) through wet milling (yield 32 %). The hydrolyzed starch was modified with three treatments: acetic anhydride (2.5g/100g), sodium tripolyphosphate (4g/100g), and sodium tripolyphosphate/ acetic anhydride (2g/1.25g by each 100 g) by extrusion. Processing conditions of extrusion were as follows: barrel temperatures were of 60, 130 and 170 °C at the feeding, transition, and high-pressure extrusion zones, respectively. Analysis of Fourier Transform Infrared spectroscopy (FTIR), showed bands exhibited of acetyl groups (1735 cm-1) and phosphates (1170 cm-1, 910 cm-1 and 525 cm-1), indicating the respective modification of starch. Besides, all modified starches not developed viscosity, which is a characteristic required for use in the encapsulation of polyphenols using the spray drying technique. As result of the modification starch, was obtained a water solubility index (WSI) from 33.8 to 44.8 %, and crystallinity from 8 to 11 %, indicating the destruction of the starch granule. Afterwards, microencapsulation of polyphenols was developed by spray drying, with a blend of 10 g of modified starch, 60 ml polyphenol extract and 30 ml of distilled water. Drying conditions were as follows: inlet air temperature 150 °C ± 1, outlet air temperature 80°C ± 5. As result of the microencapsulation: were obtained yields of 56.8 to 77.4 % and an efficiency of encapsulation from 84.6 to 91.4 %. The FTIR analysis showed evidence of microcapsules loaded with polyphenols in bands 1042 cm-1, 1038 cm-1 and 1148 cm-1. Analysis Differential scanning calorimetry (DSC) showed transition temperatures from 144.1 to 173.9 °C. For the order hand, analysis of Scanning Electron Microscopy (SEM), were observed rounded surfaces with concavities, typical feature of microcapsules produced by spray drying, how result of rapid evaporation of water. Finally, the modified starches were obtained by extrusion with good characteristics for use as cover materials by spray drying, where the phosphorylated starch was the best treatment in this work, according to the encapsulation yield, efficiency, and transition temperature.

Keywords: encapsulation, extrusion, modified starch, polyphenols, spray drying

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694 Compression-Extrusion Test to Assess Texture of Thickened Liquids for Dysphagia

Authors: Jesus Salmeron, Carmen De Vega, Maria Soledad Vicente, Mireia Olabarria, Olaia Martinez

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Dysphagia or difficulty in swallowing affects mostly elder people: 56-78% of the institutionalized and 44% of the hospitalized. Liquid food thickening is a necessary measure in this situation because it reduces the risk of penetration-aspiration. Until now, and as proposed by the American Dietetic Association in 2002, possible consistencies have been categorized in three groups attending to their viscosity: nectar (50-350 mPa•s), honey (350-1750 mPa•s) and pudding (>1750 mPa•s). The adequate viscosity level should be identified for every patient, according to her/his impairment. Nevertheless, a systematic review on dysphagia diet performed recently indicated that there is no evidence to suggest that there is any transition of clinical relevance between the three levels proposed. It was also stated that other physical properties of the bolus (slipperiness, density or cohesiveness, among others) could influence swallowing in affected patients and could contribute to the amount of remaining residue. Texture parameters need to be evaluated as possible alternative to viscosity. The aim of this study was to evaluate the instrumental extrusion-compression test as a possible tool to characterize changes along time in water thickened with various products and in the three theoretical consistencies. Six commercial thickeners were used: NM® (NM), Multi-thick® (M), Nutilis Powder® (Nut), Resource® (R), Thick&Easy® (TE) and Vegenat® (V). All of them with a modified starch base. Only one of them, Nut, also had a 6,4% of gum (guar, tara and xanthan). They were prepared as indicated in the instructions of each product and dispensing the correspondent amount for nectar, honey and pudding consistencies in 300 mL of tap water at 18ºC-20ºC. The mixture was stirred for about 30 s. Once it was homogeneously spread, it was dispensed in 30 mL plastic glasses; always to the same height. Each of these glasses was used as a measuring point. Viscosity was measured using a rotational viscometer (ST-2001, Selecta, Barcelona). Extrusion-compression test was performed using a TA.XT2i texture analyzer (Stable Micro Systems, UK) with a 25 mm diameter cylindrical probe (SMSP/25). Penetration distance was set at 10 mm and a speed of 3 mm/s. Measurements were made at 1, 5, 10, 20, 30, 40, 50 and 60 minutes from the moment samples were mixed. From the force (g)–time (s) curves obtained in the instrumental assays, maximum force peak (F) was chosen a reference parameter. Viscosity (mPa•s) and F (g) showed to be highly correlated and had similar development along time, following time-dependent quadratic models. It was possible to predict viscosity using F as an independent variable, as they were linearly correlated. In conclusion, compression-extrusion test could be an alternative and a useful tool to assess physical characteristics of thickened liquids.

Keywords: compression-extrusion test, dysphagia, texture analyzer, thickener

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693 Photophysics of a Coumarin Molecule in Graphene Oxide Containing Reverse Micelle

Authors: Aloke Bapli, Debabrata Seth

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Graphene oxide (GO) is the two-dimensional (2D) nanoscale allotrope of carbon having several physiochemical properties such as high mechanical strength, high surface area, strong thermal and electrical conductivity makes it an important candidate in various modern applications such as drug delivery, supercapacitors, sensors etc. GO has been used in the photothermal treatment of cancers and Alzheimer’s disease etc. The main idea to choose GO in our work is that it is a surface active molecule, it has a large number of hydrophilic functional groups such as carboxylic acid, hydroxyl, epoxide on its surface and in basal plane. So it can easily interact with organic fluorophores through hydrogen bonding or any other kind of interaction and easily modulate the photophysics of the probe molecules. We have used different spectroscopic techniques for our work. The Ground-state absorption spectra and steady-state fluorescence emission spectra were measured by using UV-Vis spectrophotometer from Shimadzu (model-UV-2550) and spectrofluorometer from Horiba Jobin Yvon (model-Fluoromax 4P) respectively. All the fluorescence lifetime and anisotropy decays were collected by using time-correlated single photon counting (TCSPC) setup from Edinburgh instrument (model: LifeSpec-II, U.K.). Herein, we described the photophysics of a hydrophilic molecule 7-(n,n׀-diethylamino) coumarin-3-carboxylic acid (7-DCCA) in the reverse micelles containing GO. It was observed that photophysics of dye is modulated in the presence of GO compared to photophysics of dye in the absence of GO inside the reverse micelles. Here we have reported the solvent relaxation and rotational relaxation time in GO containing reverse micelle and compare our work with normal reverse micelle system by using 7-DCCA molecule. Normal reverse micelle means reverse micelle in the absence of GO. The absorption maxima of 7-DCCA were blue shifted and emission maxima were red shifted in GO containing reverse micelle compared to normal reverse micelle. The rotational relaxation time in GO containing reverse micelle is always faster compare to normal reverse micelle. Solvent relaxation time, at lower w₀ values, is always slower in GO containing reverse micelle compare to normal reverse micelle and at higher w₀ solvent relaxation time of GO containing reverse micelle becomes almost equal to normal reverse micelle. Here emission maximum of 7-DCCA exhibit bathochromic shift in GO containing reverse micelles compared to that in normal reverse micelles because in presence of GO the polarity of the system increases, as polarity increases the emission maxima was red shifted an average decay time of GO containing reverse micelle is less than that of the normal reverse micelle. In GO containing reverse micelle quantum yield, decay time, rotational relaxation time, solvent relaxation time at λₑₓ=375 nm is always higher than λₑₓ=405 nm, shows the excitation wavelength dependent photophysics of 7-DCCA in GO containing reverse micelles.

Keywords: photophysics, reverse micelle, rotational relaxation, solvent relaxation

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692 Neuroprotection against N-Methyl-D-Aspartate-Induced Optic Nerve and Retinal Degeneration Changes by Philanthotoxin-343 to Alleviate Visual Impairments Involve Reduced Nitrosative Stress

Authors: Izuddin Fahmy Abu, Mohamad Haiqal Nizar Mohamad, Muhammad Fattah Fazel, Renu Agarwal, Igor Iezhitsa, Nor Salmah Bakar, Henrik Franzyk, Ian Mellor

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Glaucoma is the global leading cause of irreversible blindness. Currently, the available treatment strategy only involves lowering intraocular pressure (IOP); however, the condition often progresses despite lowered or normal IOP in some patients. N-methyl-D-aspartate receptor (NMDAR) excitotoxicity often occurs in neurodegeneration-related glaucoma; thus it is a relevant target to develop a therapy based on neuroprotection approach. This study investigated the effects of Philanthotoxin-343 (PhTX-343), an NMDAR antagonist, on the neuroprotection of NMDA-induced glaucoma to alleviate visual impairments. Male Sprague-Dawley rats were equally divided: Groups 1 (control) and 2 (glaucoma) were intravitreally injected with phosphate buffer saline (PBS) and NMDA (160nM), respectively, while group 3 was pre-treated with PhTX-343 (160nM) 24 hours prior to NMDA injection. Seven days post-treatments, rats were subjected to visual behavior assessments and subsequently euthanized to harvest their retina and optic nerve tissues for histological analysis and determination of nitrosative stress level using 3-nitrotyrosine ELISA. Visual behavior assessments via open field, object, and color recognition tests demonstrated poor visual performance in glaucoma rats indicated by high exploratory behavior. PhTX-343 pre-treatment appeared to preserve visual abilities as all test results were significantly improved (p < 0.05). H&E staining of the retina showed a marked reduction of ganglion cell layer thickness in the glaucoma group; in contrast, PhTX-343 significantly increased the number by 1.28-folds (p < 0.05). PhTX-343 also increased the number of cell nuclei/100μm2 within inner retina by 1.82-folds compared to the glaucoma group (p < 0.05). Toluidine blue staining of optic nerve tissues showed that PhTX-343 reduced the degeneration changes compared to the glaucoma group which exhibited vacuolation overall sections. PhTX-343 also decreased retinal 3- nitrotyrosine concentration by 1.74-folds compared to the glaucoma group (p < 0.05). All results in PhTX-343 group were comparable to control (p > 0.05). We conclude that PhTX-343 protects against NMDA-induced changes and visual impairments in the rat model by reducing nitrosative stress levels.

Keywords: excitotoxicity, glaucoma, nitrosative stress , NMDA receptor , N-methyl-D-aspartate , philanthotoxin, visual behaviour

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691 Ground Improvement Using Deep Vibro Techniques at Madhepura E-Loco Project

Authors: A. Sekhar, N. Ramakrishna Raju

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This paper is a result of ground improvement using deep vibro techniques with combination of sand and stone columns performed on a highly liquefaction susceptible site (70 to 80% sand strata and balance silt) with low bearing capacities due to high settlements located (earth quake zone V as per IS code) at Madhepura, Bihar state in northern part of India. Initially, it was envisaged with bored cast in-situ/precast piles, stone/sand columns. However, after detail analysis to address both liquefaction and improve bearing capacities simultaneously, it was analyzed the deep vibro techniques with combination of sand and stone columns is excellent solution for given site condition which may be first time in India. First after detail soil investigation, pre eCPT test was conducted to evaluate the potential depth of liquefaction to densify silty sandy soils to improve factor of safety against liquefaction. Then trail test were being carried out at site by deep vibro compaction technique with sand and stone columns combination with different spacings of columns in triangular shape with different timings during each lift of vibro up to ground level. Different spacings and timing was done to obtain the most effective spacing and timing with vibro compaction technique to achieve maximum densification of saturated loose silty sandy soils uniformly for complete treated area. Then again, post eCPT test and plate load tests were conducted at all trail locations of different spacings and timing of sand and stone columns to evaluate the best results for obtaining the required factor of safety against liquefaction and the desired bearing capacities with reduced settlements for construction of industrial structures. After reviewing these results, it was noticed that the ground layers are densified more than the expected with improved factor of safety against liquefaction and achieved good bearing capacities for a given settlements as per IS codal provisions. It was also worked out for cost-effectiveness of lightly loaded single storied structures by using deep vibro technique with sand column avoiding stone. The results were observed satisfactory for resting the lightly loaded foundations. In this technique, the most important is to mitigating liquefaction with improved bearing capacities and reduced settlements to acceptable limits as per IS: 1904-1986 simultaneously up to a depth of 19M. To our best knowledge it was executed first time in India.

Keywords: ground improvement, deep vibro techniques, liquefaction, bearing capacity, settlement

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690 Making Beehives More 'Intelligent'- The Case of Capturing, Reducing, and Managing Bee Pest Infestation in Hives through Modification of Hive Entrance Holes and the Installation of Multiple In-Hive Bee Pest Traps

Authors: Prince Amartey

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Bees are clever creatures, thus, capturing bees implies that the hives are intelligent in the sense that they have all of the required circumstances to attract and trap the bees. If the hive goes above and beyond to keep the bees in the hive and to keep the activities of in-hive pests to a minimal in order for the bees to develop to their maximum potential, the hive is becoming or is more 'intelligent'. Some bee pests, such as tiny beehive beetles, are endemic to Africa; however, the way we now extract honey by cutting off the combs and pressing for honey prevents the spread of these bees' insect enemies. However, when we explore entering the commercialization. When freshly collected combs are returned to the hives following the adoption of the frame and other systems, there is a need to consider putting in strategies to manage the accompanying pest concerns that arise with unprotected combs.The techniques for making hives more'intelligent' are thus more important presently, given that the African apicultural business does not wish to encourage the use of pesticides in the hives. This include changing the hive's entrance holes in order to improve the bees' own mechanism for defending the entry sites, as well as collecting pests by setting exterior and in-hive traps to prevent pest infiltration into hives by any means feasible. Material and Methods: The following five (5) mechanisms are proposed to make the hives more 'intelligent.' i. The usage of modified frames with five (5) beetle traps positioned horizontally on the vertical 'legs' to catch the beetle along the combs' surfaces-multiple bee ii. Baited bioelectric frame traps, which has both vertical sections of frame covered with a 3mm mesh that allows pest entry but not bees. The pest is attracted by strips of combs of honey, open brood, pollen on metal plates inserted horizontally on the vertical ‘legs’ of the frames. An electrical ‘mine’ system in place that electrocutes the pests as they step on the wires in the trap to enter the frame trap iii. The ten rounded hive entry holes are adapted as the bees are able to police the entrance to prevent entry of pest. The holes are arranged in two rows, with one on top of the other What Are the Main Contributions of Your Research?-Results Discussions and Conclusions The techniques implemented decrease pest ingress, while in-hive traps capture those that escape entry into the hives. Furthermore, the stand alteration traps larvae and stops their growth into adults. As beekeeping commercialization grows throughout Africa, these initiatives will minimize insect infestation in hives and necessarily enhance honey output.

Keywords: bee pests, modified frames, multiple beetle trap, Baited bioelectric frame traps

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689 Flow-Induced Vibration Marine Current Energy Harvesting Using a Symmetrical Balanced Pair of Pivoted Cylinders

Authors: Brad Stappenbelt

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The phenomenon of vortex-induced vibration (VIV) for elastically restrained cylindrical structures in cross-flows is relatively well investigated. The utility of this mechanism in harvesting energy from marine current and tidal flows is however arguably still in its infancy. With relatively few moving components, a flow-induced vibration-based energy conversion device augers low complexity compared to the commonly employed turbine design. Despite the interest in this concept, a practical device has yet to emerge. It is desirable for optimal system performance to design for a very low mass or mass moment of inertia ratio. The device operating range, in particular, is maximized below the vortex-induced vibration critical point where an infinite resonant response region is realized. An unfortunate consequence of this requirement is large buoyancy forces that need to be mitigated by gravity-based, suction-caisson or anchor mooring systems. The focus of this paper is the testing of a novel VIV marine current energy harvesting configuration that utilizes a symmetrical and balanced pair of horizontal pivoted cylinders. The results of several years of experimental investigation, utilizing the University of Wollongong fluid mechanics laboratory towing tank, are analyzed and presented. A reduced velocity test range of 0 to 60 was covered across a large array of device configurations. In particular, power take-off damping ratios spanning from 0.044 to critical damping were examined in order to determine the optimal conditions and hence the maximum device energy conversion efficiency. The experiments conducted revealed acceptable energy conversion efficiencies of around 16% and desirable low flow-speed operating ranges when compared to traditional turbine technology. The potentially out-of-phase spanwise VIV cells on each arm of the device synchronized naturally as no decrease in amplitude response and comparable energy conversion efficiencies to the single cylinder arrangement were observed. In addition to the spatial design benefits related to the horizontal device orientation, the main advantage demonstrated by the current symmetrical horizontal configuration is to allow large velocity range resonant response conditions without the excessive buoyancy. The novel configuration proposed shows clear promise in overcoming many of the practical implementation issues related to flow-induced vibration marine current energy harvesting.

Keywords: flow-induced vibration, vortex-induced vibration, energy harvesting, tidal energy

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688 Impact of Youth Corners and Knowledge about Human Sexuality among Young Adults and Adolescents of Nigerian Population in the Prevention of Sexually Transmitted Diseases

Authors: Gabriel I. Oke, Faremi O. Ayodeji

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Background: Access to youth Friendly Health Corners is vital for ensuring sexual reproductive health and total well being of young Adults since human sexuality has been widely misunderstood. Meanwhile, behavior of young people towards it remains at variance with the alarm. This study attempt to access the impact of youth corners also called Adolescent Friendly Health Corners on manifestation of human sexual behavior among Nigerian adolescent and young adults. Description: Hundred young adults and adolescents of both sex between the Age range of 12-25years were randomly selected from 5 secondary schools and 3 prominent universities in Southwestern Nigeria and focal group discussions (FGD) were conducted among them. Fifty secondary and primary health facilities were visited between February and June 2017 to conduct interviews for health workers and to ascertain the presence or absence of youth corners. Results: 95% of the health facilities visited lack Youth Corners section neither are they willing to make provision for it due to lack of workmanship and sponsorship. However, 5% with Youth corners does not have well-trained Counselors or a Health Educator but health professionals from nursing profession. 90% of the respondents of which 16-17 years of Age is the mean age had their first sexual exposure with no use of protection even before been introduced to what Sexuality is all about. Virtually, none of the respondents had ever visited a Youth Corner before or heard the term before. 86% have heard about the term STI before of which 60% are using protection, 10% care less about any information attached to the term STI, 4% have not heard of the term STI before even when translated to their local dialect. 20% are abstaining as at the time the study was conducted and they attribute their sexual decision to religion and parental influence. Of the age group 20-25, 45% claimed they have had symptoms of one STI or the other and 40% claimed they have been tested positive for an STI before of which 12% have positive HIV status. Promiscuous behaviors were found among them before they reach the age 16years with pornography ranking the highest, followed by masturbation. Respondents blame this on peer pressure, the lack of Youth Friendly Centers in their locality and lack of proper Sexual Orientation on time. About half of the respondents make use of contraceptives while others have varying views. We found out that inability to access Youth Friendly Centers amongst the respondents might be one of the singular reasons of their early experimentation of their sex life and lack of healthy sexual lifestyle. (95% CI, P=0.922) Conclusion: The study reveals that a connection between youth Friendly Centers and Prevention of Sexually Transmitted Diseases, therefore more sustainable Friendly Youth Corners with well-trained educators are needed in various Health facilities to checkmate the numerous risks of Young People along the path of adulthood.

Keywords: adolescents, sexually transmitted infections, reproductive health, youth corners

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687 A Comparison between Five Indices of Overweight and Their Association with Myocardial Infarction and Death, 28-Year Follow-Up of 1000 Middle-Aged Swedish Employed Men

Authors: Lennart Dimberg, Lala Joulha Ian

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Introduction: Overweight (BMI 25-30) and obesity (BMI 30+) have consistently been associated with cardiovascular (CV) risk and death since the Framingham heart study in 1948, and BMI was included in the original Framingham risk score (FRS). Background: Myocardial infarction (MI) poses a serious threat to the patient's life. In addition to BMI, several other indices of overweight have been presented and argued to replace FRS as more relevant measures of CV risk. These indices include waist circumference (WC), waist/hip ratio (WHR), sagittal abdominal diameter (SAD), and sagittal abdominal diameter to height (SADHtR). Specific research question: The research question of this study is to evaluate the interrelationship between the various body measurements, BMI, WC, WHR, SAD, and SADHtR, and which measurement is strongly associated with MI and death. Methods: In 1993, 1,000 middle-aged Caucasian, randomly selected working men of the Swedish Volvo-Renault cohort were surveyed at a nurse-led health examination with a questionnaire, EKG, laboratory tests, blood pressure, height, weight, waist, and sagittal abdominal diameter measurements. Outcome data of myocardial infarction over 28 years come from Swedeheart (the Swedish national myocardial infarction registry) and the Swedish death registry. The Aalen-Johansen and Kaplan–Meier methods were used to estimate the cumulative incidences of MI and death. Multiple logistic regression analyses were conducted to compare BMI with the other four body measurements. The risk for the various measures of obesity was calculated with outcomes of accumulated first-time myocardial infarction and death as odds ratios (OR) in quartiles. The ORs between the 4th and the 1st quartile of each measure were calculated to estimate the association between the body measurement variables and the probability of cumulative incidences of myocardial infarction (MI) over time. Double-sided P values below 0.05 will be considered statistically significant. Unadjusted odds ratios were calculated for obesity indicators, MI, and death. Adjustments for age, diabetes, SBP, and the ratio of total cholesterol/HDL-C and blue/white collar status were performed. Results: Out of 1000 people, 959 subjects had full information about the five different body measurements. Of those, 90 participants had a first MI, and 194 persons died. The study showed that there was a high and significant correlation between the five different body measurements, and they were all associated with CVD risk factors. All body measurements were significantly associated with MI, with the highest (OR=3.6) seen for SADHtR and WC. After adjustment, all but SADHtR remained significant with weaker ORs. As for all-cause mortality, WHR (OR=1.7), SAD (OR=1.9), and SADHtR (OR=1.6) were significantly associated, but not WC and BMI. However, after adjustment, only WHR and SAD were significantly associated with death, but with attenuated ORs.

Keywords: BMI, death, epidemiology, myocardial infarction, risk factor, sagittal abdominal diameter, sagittal abdominal diameter to height, waist circumference, waist-hip ratio

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686 Identification of Phenolic Compounds and Study the Antimicrobial Property of Eleaocarpus Ganitrus Fruits

Authors: Velvizhi Dharmalingam, Rajalaksmi Ramalingam, Rekha Prabhu, Ilavarasan Raju

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Background: The use of herbal products for various therapeutic regimens has increased tremendously in the developing countries. Elaeocarpus ganitrus(Rudraksha) is a broad-leaved tree, belonging to the family Elaeocarpaceae found in tropical and subtropical areas. It is popular in an indigenous system of medicine like Ayurveda, Siddha, and Unani. According to Ayurvedic medicine, Rudraksha is used in the managing of blood pressure, asthma, mental disorders, diabetes, gynaecological disorders, neurological disorders such as epilepsy and liver diseases. Objectives: The present study aimed to study the physicochemical parameters of Elaeocarpus ganitrus(fruits) and identify the phenolic compounds (gallic acid, ellagic acid, and chebulinic acid). To estimate the microbial load and the antibacterial activity of extract of Elaeocarpus ganitrus for selective pathogens. Methodology: The dried powdered fruit of Elaeocarpus ganitrus was performed the physicochemical parameters (such as Loss on drying, Alcohol soluble extractive, Water soluble extractive, Total ash and Acid insoluble ash) and pH was measured. The dried coarse powdered fruit of Elaeocarpus ganitrus was extracted successively with hexane, chloroform, ethylacetate and aqueous alcohol by cold percolation method. Identification of phenolic compounds (gallic acid, ellagic acid, chebulinic acid) was done by HPTLC method and confirmed by co-TLC using different solvent system.The successive extracts of Elaeocarpus ganitrus and standards (like gallic acid, ellagic acid, and chebulinic acid) was approximately weighed and made up with alcohol. HPTLC (CAMAG) analysis was performed on a TLC over silica gel 60F254 precoated aluminium plate, layer thickness 0.2 mm (E.Merck, Germany) by using ATS4, Visualizer and Scanner with wavelength at 254 nm, 366 nm and derivatized with different reagents. The microbial load such as total bacterial count, total fungal count, Enterobacteria, Escherichia coli, Salmonella species, Staphylococcus aureus and Pseudomonas aeruginosa by serial dilution method and antibacterial activity of was measured by Kirby bauer method for selective pathogens. Results: The physicochemical parameter of Elaeocarpus ganitrus was studied for standardization of crude drug. Among all the successive extracts were identified with phenolic compounds and Elaeocarpus ganitrus extract having potent antibacterial activity against gram-positive and gram-negative bacteria.

Keywords: antimicrobial activity, Elaeocarpus ganitrus, HPTLC, phenolic compounds

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685 Antimicrobial Activity of 2-Nitro-1-Propanol and Lauric Acid against Gram-Positive Bacteria

Authors: Robin Anderson, Elizabeth Latham, David Nisbet

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Propagation and dissemination of antimicrobial resistant and pathogenic microbes from spoiled silages and composts represents a serious public health threat to humans and animals. In the present study, the antimicrobial activity of the short chain nitro-compound, 2-nitro-1-propanol (9 mM) as well as the medium chain fatty acid, lauric acid, and its glycerol monoester, monolaurin, (each at 25 and 17 µmol/mL, respectfully) were investigated against select pathogenic and multi-drug resistant antimicrobial resistant Gram-positive bacteria common to spoiled silages and composts. In an initial study, we found that growth rates of a multi-resistant Enterococcus faecalis (expressing resistance against erythromycin, quinupristin/dalfopristin and tetracycline) and Staphylococcus aureus strain 12600 (expressing resistance against erythromycin, linezolid, penicillin, quinupristin/dalfopristin and vancomycin) were more than 78% slower (P < 0.05) by 2-nitro-1-propanol treatment during culture (n = 3/treatment) in anaerobically prepared ½ strength Brain Heart Infusion broth at 37oC when compared to untreated controls (0.332 ± 0.04 and 0.108 ± 0.03 h-1, respectively). The growth rate of 2-nitro-1-propanol-treated Listeria monocytogenes was also decreased by 96% (P < 0.05) when compared to untreated controls cultured similarly (0.171 ± 0.01 h-1). Maximum optical densities measured at 600 nm were lower (P < 0.05) in 2-nitro-1-propanol-treated cultures (0.053 ± 0.01, 0.205 ± 0.02 and 0.041 ± 0.01, respectively) than in untreated controls (0.483 ± 0.02, 0.523 ± 0.01 and 0.427 ± 0.01, respectively) for E. faecalis, S. aureus and L. monocytogenes, respectively. When tested against mixed microbial populations during anaerobic 24 h incubation of spoiled silage, significant effects of treatment with 1 mg 2-nitro-1-propanol (approximately 9.5 µmol/g) or 5 mg lauric acid/g (approximately 25 µmol/g) on populations of wildtype Enterococcus and Listeria were not observed. Mixed populations treated with 5 mg monolaurin/g (approximately 17 µmol/g) had lower (P < 0.05) viable cell counts of wildtype enterococci than untreated controls after 6 h incubation (2.87 ± 1.03 versus 5.20 ± 0.25 log10 colony forming units/g, respectively) but otherwise significant effects of monolaurin were not observed. These results reveal differential susceptibility of multi-drug resistant enterococci and staphylococci as well as L. monocytogenes to the inhibitory activity of 2-nitro-1-propanol and the medium chain fatty acid, lauric acid and its glycerol monoester, monolaurin. Ultimately, these results may lead to improved treatment technologies to preserve the microbiological safety of silages and composts.

Keywords: 2-nitro-1-propanol, lauric acid, monolaurin, gram positive bacteria

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684 Using Fractal Architectures for Enhancing the Thermal-Fluid Transport

Authors: Surupa Shaw, Debjyoti Banerjee

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Enhancing heat transfer in compact volumes is a challenge when constrained by cost issues, especially those associated with requirements for minimizing pumping power consumption. This is particularly acute for electronic chip cooling applications. Technological advancements in microelectronics have led to development of chip architectures that involve increased power consumption. As a consequence packaging, technologies are saddled with needs for higher rates of power dissipation in smaller form factors. The increasing circuit density, higher heat flux values for dissipation and the significant decrease in the size of the electronic devices are posing thermal management challenges that need to be addressed with a better design of the cooling system. Maximizing surface area for heat exchanging surfaces (e.g., extended surfaces or “fins”) can enable dissipation of higher levels of heat flux. Fractal structures have been shown to maximize surface area in compact volumes. Self-replicating structures at multiple length scales are called “Fractals” (i.e., objects with fractional dimensions; unlike regular geometric objects, such as spheres or cubes whose volumes and surface area values scale as integer values of the length scale dimensions). Fractal structures are expected to provide an appropriate technology solution to meet these challenges for enhanced heat transfer in the microelectronic devices by maximizing surface area available for heat exchanging fluids within compact volumes. In this study, the effect of different fractal micro-channel architectures and flow structures on the enhancement of transport phenomena in heat exchangers is explored by parametric variation of fractal dimension. This study proposes a model that would enable cost-effective solutions for thermal-fluid transport for energy applications. The objective of this study is to ascertain the sensitivity of various parameters (such as heat flux and pressure gradient as well as pumping power) to variation in fractal dimension. The role of the fractal parameters will be instrumental in establishing the most effective design for the optimum cooling of microelectronic devices. This can help establish the requirement of minimal pumping power for enhancement of heat transfer during cooling. Results obtained in this study show that the proposed models for fractal architectures of microchannels significantly enhanced heat transfer due to augmentation of surface area in the branching networks of varying length-scales.

Keywords: fractals, microelectronics, constructal theory, heat transfer enhancement, pumping power enhancement

Procedia PDF Downloads 303
683 Assessment of Physical Activity Patterns in Patients with Cardiopulmonary Diseases

Authors: Ledi Neçaj

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Objectives: The target of this paper is (1) to explain objectively physical activity model throughout three chronic cardiopulmonary conditions, and (2) to study the connection among physical activity dimensions with disease severity, self-reported physical and emotional functioning, and exercise performance. Material and Methods: This is a cross-sectional study of patients in their domestic environment. Patients with cardiopulmonary diseases were: chronic obstructive pulmonary disease (COPD), (n-63), coronary heart failure (n=60), and patients with implantable cardioverter defibrillator (n=60). Main results measures: Seven ambulatory physical activity dimensions (total steps, percentage time active, percentage time ambulating at low, medium, and hard intensity, maximum cadence for 30 non-stop minutes, and peak performance) have been measured with an accelerometer. Results: Subjects with COPD had the lowest amount of ambulatory physical activity compared with topics with coronary heart failure and cardiac dysrhythmias (all 7 interest dimensions, P<.05); total step counts have been: 5319 as opposed to 7464 as opposed to 9570, respectively. Six-minute walk distance becomes correlated (r=.44-.65, P<.01) with all physical activity dimensions inside the COPD pattern, the most powerful correlations being with total steps and peak performance. In topics with cardiac impairment, maximal oxygen intake had the most effective small to slight correlations with five of the physical activity dimensions (r=.22-.40, P<.05). In contrast, correlations among 6-minute walk test distance and physical activity have been higher (r=.48-.61, P<.01) albeit in a smaller pattern of most effective patients with coronary heart failure. For all three samples, self-reported physical and mental health functioning, age, frame mass index, airflow obstruction, and ejection fraction had both exceptionally small and no significant correlations with physical activity. Conclusions: Findings from this study present a profitable benchmark of physical activity patterns in individuals with cardiopulmonary diseases for comparison with future studies. All seven dimensions of ambulatory physical activity have disfavor between subjects with COPD, heart failure, and cardiac dysrhythmias. Depending on the research or clinical goal, the use of one dimension, such as total steps, may be sufficient. Although physical activity had high correlations with performance on a six-minute walk test relative to other variables, accelerometers-based physical activity monitoring provides unique, important information about real-world behavior in patients with cardiopulmonary not already captured with existing measures.

Keywords: ambulatory physical activity, walking, monitoring, COPD, heart failure, implantable defibrillator, exercise performance

Procedia PDF Downloads 74
682 Bioefficacy of Ocimum sanctum on Reproductive Performance of Red Cotton Bug, Dysdercus koenigii (Heteroptera: Pyrrhocoriedae)

Authors: Kamal Kumar Gupta, Sunil Kayesth

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Dysdercus koenigii is serious pest of cotton and other malvaceous crop. Present research work aimed at ecofriendly approach for management of pest by plant extracts. The impact of Ocimum sanctum was studied on reproductive performance of Dysdercus koenigii. The hexane extract of Ocimum leaves was prepared by ‘cold extraction method’. The newly emerged fifth instar nymphs were exposed to the extract of concentrations ranging from 0.1% to 0.00625% by ‘thin film residual method’ for a period of 24h. Reproductive fitness of the adults emerged from the treated nymphs was evaluated by assessing their courtship behaviour, oviposition behaviour, and fertility. The studies indicated that treatment of Dysdercus with the hexane extract of Ocimum altered their courtship behaviour. Consequently, the treated males exhibited less sexual activity, performed fewer mounting attempts, increased time to mate and showed decreased percent successful mating. The females often rejected courting treated male by shaking the abdomen. Similarly, the treated females in many cases remained non-receptive to the courting male. Premature termination of mating in the mating pairs prior to insemination further decreased the mating success of the treated adults. Maximum abbreviation of courtship behaviour was observed in the experimental set up where both the males and the females were treated. Only females which mate successfully were observed for study of oviposition behaviour. The treated females laid lesser number of egg batches and eggs in their life span. The eggs laid by these females were fertile indicating insemination of the female. However, percent hatchability was lesser than control. The effects of hexane extract were dose dependent. Treatment with 0.1% and 0.05% extract altered courtship behaviour. Doses of concentrations less than 0.05% did not affect courtship behaviour but altered the oviposition behaviour and fertility. Significant reduction in the fecundity and fertility was observed in the treatments at concentration as low as 0.00625%. The GCMS analysis of the extract revealed a plethora of phytochemicals including juvenile hormone mimics, and the intermediates of juvenile hormone biosynthesis. Therefore, some of these compounds individually or synergistically impair reproductive behaviour of Dysdercus. Alteration of courtship behaviour and suppression of fecundity and fertility with the help of plant extracts has wide potentials in suppression of pest population and ‘integrated pest management’.

Keywords: courtship behaviour, Dysdercus koenigii, Ocimum sanctum, oviposition behaviour

Procedia PDF Downloads 243
681 Liquid Food Sterilization Using Pulsed Electric Field

Authors: Tanmaya Pradhan, K. Midhun, M. Joy Thomas

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Increasing the shelf life and improving the quality are important objectives for the success of packaged liquid food industry. One of the methods by which this can be achieved is by deactivating the micro-organisms present in the liquid food through pasteurization. Pasteurization is done by heating, but some serious disadvantages such as the reduction in food quality, flavour, taste, colour, etc. were observed because of heat treatment, which leads to the development of newer methods instead of pasteurization such as treatment using UV radiation, high pressure, nuclear irradiation, pulsed electric field, etc. In recent years the use of the pulsed electric field (PEF) for inactivation of the microbial content in the food is gaining popularity. PEF uses a very high electric field for a short time for the inactivation of microorganisms, for which we require a high voltage pulsed power source. Pulsed power sources used for PEF treatments are usually in the range of 5kV to 50kV. Different pulse shapes are used, such as exponentially decaying and square wave pulses. Exponentially decaying pulses are generated by high power switches with only turn-on capacity and, therefore, discharge the total energy stored in the capacitor bank. These pulses have a sudden onset and, therefore, a high rate of rising but have a very slow decay, which yields extra heat, which is ineffective in microbial inactivation. Square pulses can be produced by an incomplete discharge of a capacitor with the help of a switch having both on/off control or by using a pulse forming network. In this work, a pulsed power-based system is designed with the help of high voltage capacitors and solid-state switches (IGBT) for the inactivation of pathogenic micro-organism in liquid food such as fruit juices. The high voltage generator is based on the Marx generator topology, which can produce variable amplitude, frequency, and pulse width according to the requirements. Liquid food is treated in a chamber where pulsed electric field is produced between stainless steel electrodes using the pulsed output voltage of the supply. Preliminary bacterial inactivation tests were performed by subjecting orange juice inoculated with Escherichia Coli bacteria. With the help of the developed pulsed power source and the chamber, the inoculated orange has been PEF treated. The voltage was varied to get a peak electric field up to 15kV/cm. For a total treatment time of 200µs, a 30% reduction in the bacterial count has been observed. The detailed results and analysis will be presented in the final paper.

Keywords: Escherichia coli bacteria, high voltage generator, microbial inactivation, pulsed electric field, pulsed forming line, solid-state switch

Procedia PDF Downloads 160
680 Assessment of Agricultural Intervention on Ecosystem Services in the Central-South Zone of Chile

Authors: Steven Hidalgo, Patricio Neumann

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The growth of societies has increased the consumption of raw materials and food obtained from nature. This has influenced the services offered by ecosystems to humans, mainly supply and regulation services. One of the indicators used to evaluate these services is Net Primary Productivity (NPP), which is understood as the energy stored in the form of biomass by primary organisms through the process of photosynthesis and respiration. The variation of NPP by defined area produces changes in the properties of terrestrial and aquatic ecosystems, which alter factors such as biodiversity, nutrient cycling, carbon storage and water quality. The analysis of NPP to evaluate variations in ecosystem services includes harvested NPP (understood as provisioning services), which is the raw material from agricultural systems used by humans as a source of energy and food, and the remaining NPP (expressed as a regulating service) or the amount of biomass that remains in ecosystems after the harvesting process, which is mainly related to factors such as biodiversity. Given that agriculture is a fundamental pillar of Chile's integral development, the purpose of this study is to evaluate provisioning and regulating ecosystem services in the agricultural sector, specifically in cereal production, in the communes of the central-southern regions of Chile through a conceptual framework based on the quantification of the fraction of Human Appropriation of Net Primary Productivity (HANPP) and the fraction remaining in the ecosystems (NPP remaining). A total of 161 communes were analyzed in the regions of O'Higgins, Maule, Ñuble, Bio-Bío, La Araucanía and Los Lagos, which are characterized by having the largest areas planted with cereals. It was observed that the region of La Araucanía produces the greatest amount of dry matter, understood as provisioning service, where Victoria is the commune with the highest cereal production in the country. In addition, the maximum value of HANPP was in the O'Higgins region, highlighting the communes of Coltauco, Quinta de Tilcoco, Placilla and Rengo. On the other hand, the communes of Futrono, Pinto, Lago Ranco and Pemuco, whose cereal production was important during the study, had the highest values of remaining NPP as a regulating service. Finally, an inverse correlation was observed between the provisioning and regulating ecosystem services, i.e., the higher the cereal or dry matter production in a defined area, the lower the net primary production remaining in the ecosystems. Based on this study, future research will focus on the evaluation of ecosystem services associated with other crops, such as forestry plantations, whose activity is an important part of the country's productive sector.

Keywords: provisioning services, regulating services, net primary productivity, agriculture

Procedia PDF Downloads 81
679 Ex-vivo Bio-distribution Studies of a Potential Lung Perfusion Agent

Authors: Shabnam Sarwar, Franck Lacoeuille, Nadia Withofs, Roland Hustinx

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After the development of a potential surrogate of MAA, and its successful application for the diagnosis of pulmonary embolism in artificially embolized rats’ lungs, this microparticulate system were radiolabelled with gallium-68 to synthesize 68Ga-SBMP with high radiochemical purity >99%. As a prerequisite step of clinical trials, 68Ga- labelled starch based microparticles (SBMP) were analysed for their in-vivo behavior in small animals. The purpose of the presented work includes the ex-vivo biodistribution studies of 68Ga-SBMP in order to assess the activity uptake in target organs with respect to time, excretion pathways of the radiopharmaceutical, %ID/g in major organs, T/NT ratios, in-vivo stability of the radiotracer and subsequently the microparticles in the target organs. Radiolabelling of starch based microparticles was performed by incubating it with 68Ga generator eluate (430±26 MBq) at room temperature and pressure without using any harsh reaction condition. For Ex-vivo biodistribution studies healthy White Wistar rats weighing between 345-460 g were injected intravenously 68Ga-SBMP 20±8 MBq, containing about 2,00,000-6,00,000 SBMP particles in a volume of 700µL. The rats were euthanized at predefined time intervals (5min, 30min, 60min and 120min) and their organ parts were cut, washed, and put in the pre-weighed tubes and measured for radioactivity counts through automatic Gamma counter. The 68Ga-SBMP produced >99% RCP just after 10-20 min incubation through a simple and robust procedure. Biodistribution of 68Ga-SBMP showed that initially just after 5 min post injection major uptake was observed in the lungs following by blood, heart, liver, kidneys, bladder, urine, spleen, stomach, small intestine, colon, skin and skeleton, thymus and at last the smallest activity was found in brain. Radioactivity counts stayed stable in lungs with gradual decrease with the passage of time, and after 2h post injection, almost half of the activity were seen in lungs. This is a sufficient time to perform PET/CT lungs scanning in humans while activity in the liver, spleen, gut and urinary system decreased with time. The results showed that urinary system is the excretion pathways instead of hepatobiliary excretion. There was a high value of T/NT ratios which suggest fine tune images for PET/CT lung perfusion studies henceforth further pre-clinical studies and then clinical trials should be planned in order to utilize this potential lung perfusion agent.

Keywords: starch based microparticles, gallium-68, biodistribution, target organs, excretion pathways

Procedia PDF Downloads 153
678 Integrating Computational Modeling and Analysis with in Vivo Observations for Enhanced Hemodynamics Diagnostics and Prognosis

Authors: Shreyas S. Hegde, Anindya Deb, Suresh Nagesh

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Computational bio-mechanics is developing rapidly as a non-invasive tool to assist the medical fraternity to help in both diagnosis and prognosis of human body related issues such as injuries, cardio-vascular dysfunction, atherosclerotic plaque etc. Any system that would help either properly diagnose such problems or assist prognosis would be a boon to the doctors and medical society in general. Recently a lot of work is being focused in this direction which includes but not limited to various finite element analysis related to dental implants, skull injuries, orthopedic problems involving bones and joints etc. Such numerical solutions are helping medical practitioners to come up with alternate solutions for such problems and in most cases have also reduced the trauma on the patients. Some work also has been done in the area related to the use of computational fluid mechanics to understand the flow of blood through the human body, an area of hemodynamics. Since cardio-vascular diseases are one of the main causes of loss of human life, understanding of the blood flow with and without constraints (such as blockages), providing alternate methods of prognosis and further solutions to take care of issues related to blood flow would help save valuable life of such patients. This project is an attempt to use computational fluid dynamics (CFD) to solve specific problems related to hemodynamics. The hemodynamics simulation is used to gain a better understanding of functional, diagnostic and theoretical aspects of the blood flow. Due to the fact that many fundamental issues of the blood flow, like phenomena associated with pressure and viscous forces fields, are still not fully understood or entirely described through mathematical formulations the characterization of blood flow is still a challenging task. The computational modeling of the blood flow and mechanical interactions that strongly affect the blood flow patterns, based on medical data and imaging represent the most accurate analysis of the blood flow complex behavior. In this project the mathematical modeling of the blood flow in the arteries in the presence of successive blockages has been analyzed using CFD technique. Different cases of blockages in terms of percentages have been modeled using commercial software CATIA V5R20 and simulated using commercial software ANSYS 15.0 to study the effect of varying wall shear stress (WSS) values and also other parameters like the effect of increase in Reynolds number. The concept of fluid structure interaction (FSI) has been used to solve such problems. The model simulation results were validated using in vivo measurement data from existing literature

Keywords: computational fluid dynamics, hemodynamics, blood flow, results validation, arteries

Procedia PDF Downloads 389
677 Numerical and Experimental Investigation of Air Distribution System of Larder Type Refrigerator

Authors: Funda Erdem Şahnali, Ş. Özgür Atayılmaz, Tolga N. Aynur

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Almost all of the domestic refrigerators operate on the principle of the vapor compression refrigeration cycle and removal of heat from the refrigerator cabinets is done via one of the two methods: natural convection or forced convection. In this study, airflow and temperature distributions inside a 375L no-frost type larder cabinet, in which cooling is provided by forced convection, are evaluated both experimentally and numerically. Airflow rate, compressor capacity and temperature distribution in the cooling chamber are known to be some of the most important factors that affect the cooling performance and energy consumption of a refrigerator. The objective of this study is to evaluate the original temperature distribution in the larder cabinet, and investigate for better temperature distribution solutions throughout the refrigerator domain via system optimizations that could provide uniform temperature distribution. The flow visualization and airflow velocity measurements inside the original refrigerator are performed via Stereoscopic Particle Image Velocimetry (SPIV). In addition, airflow and temperature distributions are investigated numerically with Ansys Fluent. In order to study the heat transfer inside the aforementioned refrigerator, forced convection theories covering the following cases are applied: closed rectangular cavity representing heat transfer inside the refrigerating compartment. The cavity volume has been represented with finite volume elements and is solved computationally with appropriate momentum and energy equations (Navier-Stokes equations). The 3D model is analyzed as transient, with k-ε turbulence model and SIMPLE pressure-velocity coupling for turbulent flow situation. The results obtained with the 3D numerical simulations are in quite good agreement with the experimental airflow measurements using the SPIV technique. After Computational Fluid Dynamics (CFD) analysis of the baseline case, the effects of three parameters: compressor capacity, fan rotational speed and type of shelf (glass or wire) are studied on the energy consumption; pull down time, temperature distributions in the cabinet. For each case, energy consumption based on experimental results is calculated. After the analysis, the main effective parameters for temperature distribution inside a cabin and energy consumption based on CFD simulation are determined and simulation results are supplied for Design of Experiments (DOE) as input data for optimization. The best configuration with minimum energy consumption that provides minimum temperature difference between the shelves inside the cabinet is determined.

Keywords: air distribution, CFD, DOE, energy consumption, experimental, larder cabinet, refrigeration, uniform temperature

Procedia PDF Downloads 87
676 The Language of Science in Higher Education: Related Topics and Discussions

Authors: Gurjeet Singh, Harinder Singh

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In this paper, we present "The Language of Science in Higher Education: Related Questions and Discussions". Linguists have written and researched in depth the role of language in science. On this basis, it is clear that language is not just a medium or vehicle for communicating knowledge and ideas. Nor are there mere signs of language knowledge and conversion of ideas into code. In the process of reading and writing, everyone thinks deeply and struggles to understand concepts and make sense. Linguistics play an important role in achieving concepts. In the context of such linguistic diversity, there is no straightforward and simple answer to the question of which language should be the language of advanced science and technology. Many important topics related to this issue are as follows: Involvement in practical or Deep theoretical issues. Languages for the study of science and other subjects. Language issues of science to be considered separate from the development of science, capitalism, colonial history, the worldview of the common man. The democratization of science and technology education in India is possible only by providing maximum reading/resource material in regional languages. The scientific research should be increase to chances of understanding the subject. Multilingual instead or monolingual. As far as deepening the understanding of the subject is concerned, we can shed light on it based on two or three experiences. An attempt was made to make the famous sociological journal Economic and Political Weekly Hindi almost three decades ago. There were many obstacles in this work. The original articles written in Hindi were not found, and the papers and articles of the English Journal were translated into Hindi, and a journal called Sancha was taken out. Equally important is the democratization of knowledge and the deepening of understanding of the subject. However, the question is that if higher education in science is in Hindi or other languages, then it would be a problem to get job. In fact, since independence, English has been dominant in almost every field except literature. There are historical reasons for this, which cannot be reversed. As mentioned above, due to colonial rule, even before independence, English was established as a language of communication, the language of power/status, the language of higher education, the language of administration, and the language of scholarly discourse. After independence, attempts to make Hindi or Hindustani the national language in India were unsuccessful. Given this history and current reality, higher education should be multilingual or at least bilingual. Translation limits should also be increased for those who choose the material for translation. Writing in regional languages on science, making knowledge of various international languages available in Indian languages, etc., is equally important for all to have opportunities to learn English.

Keywords: language, linguistics, literature, culture, ethnography, punjabi, gurmukhi, higher education

Procedia PDF Downloads 74
675 The Relationship between Anthropometric Obesity Indices and Insulin in Children with Metabolic Syndrome

Authors: Mustafa M. Donma, Orkide Donma

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The number of indices developed for the evaluation of obesity both in adults and pediatric population is ever increasing. These indices are also used in cases with metabolic syndrome (MetS), mostly the ultimate form of morbid obesity. Aside from anthropometric measurements, formulas constituted using these parameters also find clinical use. These formulas can be listed as two groups; being weight-dependent and –independent. Some are extremely sophisticated equations and their clinical utility is questionable in routine clinical practice. The aim of this study is to compare presently available obesity indices and find the most practical one. Their associations with MetS components were also investigated to determine their capacities in differential diagnosis of morbid obesity with and without MetS. Children with normal body mass index (N-BMI) and morbid obesity were recruited for this study. Three groups were constituted. Age- and sex- dependent BMI percentiles for morbid obese (MO) children were above 99 according to World Health Organization tables. Of them, those with MetS findings were evaluated as MetS group. Children, whose values were between 85 and 15 were included in N-BMI group. The study protocol was approved by the Ethics Committee of the Institution. Parents filled out informed consent forms to participate in the study. Anthropometric measurements and blood pressure values were recorded. Body mass index, hip index (HI), conicity index (CI), triponderal mass index (TPMI), body adiposity index (BAI), body shape index (ABSI), body roundness index (BRI), abdominal volume index (AVI), waist-to-hip ratio (WHR) and waist circumference+hip circumference/2 ((WC+HC)/2) were the formulas examined within the scope of this study. Routine biochemical tests including fasting blood glucose (FBG), insulin (INS), triglycerides (TRG), high density lipoprotein-cholesterol (HDL-C) were performed. Statistical package program SPSS was used for the evaluation of study data. p<0.05 was accepted as the statistical significance degree. Hip index did not differ among the groups. A statistically significant difference was noted between N-BMI and MetS groups in terms of ABSI. All the other indices were capable of making discrimination between N-BMI-MO, N-BMI- MetS and MO-MetS groups. No correlation was found between FBG and any obesity indices in any groups. The same was true for INS in N-BMI group. Insulin was correlated with BAI, TPMI, CI, BRI, AVI and (WC+HC)/2 in MO group without MetS findings. In MetS group, the only index, which was correlated with INS was (WC+HC)/2. These findings have pointed out that complicated formulas may not be required for the evaluation of the alterations among N-BMI and various obesity groups including MetS. The simple easily computable weight-independent index, (WC+HC)/2, was unique, because it was the only index, which exhibits a valuable association with INS in MetS group. It did not exhibit any correlation with other obesity indices showing associations with INS in MO group. It was concluded that (WC+HC)/2 was pretty valuable practicable index for the discrimination of MO children with and without MetS findings.

Keywords: children, insulin, metabolic syndrome, obesity indices

Procedia PDF Downloads 58
674 Conserving Naubad Karez Cultural Landscape – a Multi-Criteria Approach to Urban Planning

Authors: Valliyil Govindankutty

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Human civilizations across the globe stand testimony to water being one of the major interaction points with nature. The interactions with nature especially in drier areas revolve around water, be it harnessing, transporting, usage and management. Many ingenious ideas were born, nurtured and developed for harnessing, transporting, storing and distributing water through the areas in the drier parts of the world. Many methods of water extraction, collection and management could be found throughout the world, some of which are associated with efficient, sustained use of surface water, ground water and rain water. Karez is one such ingenious method of collection, transportation, storage and distribution of ground water. Most of the Karez systems in India were developed during reign of Muslim dynasties with ruling class descending from Persia or having influential connections and inviting expert engineers from there. Karez have strongly influenced the village socio-economic organisations due to multitude of uses they were brought into. These are masterpiece engineering structures to collect groundwater and direct it, through a subsurface gallery with a gradual slope, to surface canals that provide water to settlements and agricultural fields. This ingenious technology, karez was result of need for harnessing groundwater in arid areas like that of Bidar. The study views this traditional technology in historical perspective linked to sustainable utilization and management of groundwater and above all the immediate environment. The karez system is one of the best available demonstration of human ingenuity and adaptability to situations and locations of water scarcity. Bidar, capital of erstwhile Bahmani sultanate with a history of more than 700 years or more is one of the heritage cities of present Karnataka State. The unique water systems of Bidar along with other historic entities have been listed under World Heritage Watch List by World Monument Fund. The Historical or cultural landscape in Bidar is very closely associated to the natural resources of the region, Karez systems being one of the best examples. The Karez systems were the lifeline of Bidar’s historical period providing potable water, fulfilling domestic and irrigation needs, both within and outside the fort enclosures. These systems are still functional, but under great pressure and threat of rapid and unplanned urbanisation. The change in land use and fragmentation of land are already paving way for irreversible modification of the karez cultural and geographic landscape. The Paper discusses the significance of character defining elements of Naubad Karez Landscape, highlights the importance of conserving cultural heritage and presents a geographical approach to its revival.

Keywords: Karez, groundwater, traditional water harvesting, cultural heritage landscape, urban planning

Procedia PDF Downloads 478
673 Lessons from Patients Expired due to Severe Head Injuries Treated in Intensive Care Unit of Lady Reading Hospital Peshawar

Authors: Mumtaz Ali, Hamzullah Khan, Khalid Khanzada, Shahid Ayub, Aurangzeb Wazir

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Objective: To analyse the death of patients treated in neuro-surgical ICU for severe head injuries from different perspectives. The evaluation of the data so obtained to help improve the health care delivery to this group of patients in ICU. Study Design: It is a descriptive study based on retrospective analysis of patients presenting to neuro-surgical ICU in Lady Reading Hospital, Peshawar. Study Duration: It covered the period between 1st January 2009 to 31st December 2009. Material and Methods: The Clinical record of all the patients presenting with the clinical radiological and surgical features of severe head injuries, who expired in neuro-surgical ICU was collected. A separate proforma which mentioned age, sex, time of arrival and death, causes of head injuries, the radiological features, the clinical parameters, the surgical and non surgical treatment given was used. The average duration of stay and the demographic and domiciliary representation of these patients was noted. The record was analyzed accordingly for discussion and recommendations. Results: Out of the total 112 (n-112) patients who expired in one year in the neuro-surgical ICU the young adults made up the majority 64 (57.14%) followed by children, 34 (30.35%) and then the elderly age group: 10 (8.92%). Road traffic accidents were the major cause of presentation, 75 (66.96%) followed by history of fall; 23 (20.53%) and then the fire arm injuries; 13 (11.60%). The predominant CT scan features of these patients on presentation was cerebral edema, and midline shift (diffuse neuronal injuries). 46 (41.07%) followed by cerebral contusions. 28 (25%). The correctable surgical causes were present only in 18 patients (16.07%) and the majority 94 (83.92%) were given conservative management. Of the 69 (n=69) patients in which CT scan was repeated; 62 (89.85%) showed worsening of the initial CT scan abnormalities while in 7 cases (10.14%) the features were static. Among the non surgical cases both ventilatory therapy in 7 (6.25%) and tracheostomy in 39 (34.82%) failed to change the outcome. The maximum stay in the neuro ICU leading upto the death was 48 hours in 35 (31.25%) cases followed by 31 (27.67%) cases in 24 hours; 24 (21.42%) in one week and 16 (14.28%) in 72 hours. Only 6 (5.35%) patients survived more than a week. Patients were received from almost all the districts of NWFP except. The Hazara division. There were some Afghan refugees as well. Conclusion: Mortality following the head injuries is alarmingly high despite repeated claims about the professional and administrative improvement. Even places like ICU could not change the out come according to the desired aims and objectives in the present set up. A rethinking is needed both at the individual and institutional level among the concerned quarters with a clear aim at the more scientific grounds. Only then one can achieve the desired results.

Keywords: Glasgow Coma Scale, pediatrics, geriatrics, Peshawar

Procedia PDF Downloads 334
672 The Awareness of Cardiovascular Diseases among General Population in Western Regions of Saudi Arabia

Authors: Ali Saeed Alghamdi, Basel Mazen Alsolami, Basel Saeed Alghamdi, Muhanad Saleh Alzahrani Alamri, Salman Anwar Thabet, Abdulhalim J. Kinsara

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Objectives: This study measures the knowledge of the cardiovascular disease among the general population in western regions of Saudi Arabia, and it aimed to increase the level of awareness about cardiovascular diseases among the general population by providing an awareness lecture that included information about the risk factors, major symptoms, and prevention of cardiovascular diseases. The lecture has been attached at the end of the questionnaire. Setting: This study was conducted through an online questionnaire that included our aim and main objectives that targeted the general population in the Western regions of Saudi Arabia (Makkah and Madinah regions). Participants: This study participants were 460 collected through an online questionnaire. Methods: All Saudi citizens and residents who live in the western region of Saudi Arabia aged 18 years and above will be invited to participate voluntarily. A pre-structured questionnaire was designed to collect data on age, gender, marital status, education level, occupation, lifestyle habits, and history of heart diseases, with cardiac symptoms and risk factors sections. Results: The majority of respondents were females (74.8%) and Saudis. The knowledge about cardiovascular disease risk factors was weak. Only (18.5%) scores an excellent response regarding risk factors awareness. Lack of exercise, stress, and obesity were the most known risk factors. Regarding cardiovascular disease symptoms, chest pain scores the highest symptom (87.6%) among other symptoms like dyspnea, syncope, and excessive sweating. Participants revealed a poor awareness regarding cardiovascular disease symptoms also (0.9%). However, preventable factors for cardiovascular diseases were more knowledgeable than others categories in this study (60% fall into excellent knowledge). Smoking cessation, normal cholesterol level, and normal blood pressure score the highest preventable methods (92.2%), (88.6%), and (78.7%) respectively. 83.7% of the participant have attended the awareness lecture, and 99 of the attendees reported that the lecture increased their knowledge about cardiovascular disease. Conclusion: This study discussed the level of community awareness of cardiovascular disease in terms of symptoms, risk factors, and protective factors. We found a huge lack of the participant's level of knowledge about the disease and how to prevent it. Moreover, we measure the prevalence of the comorbidities among our participants (diabetes, hypertension, hypercholesterolemia/ hypertriglyceridemia) and their extent of adherence to their medication. In conclusion, this study not only demonstrates awareness of cardiovascular disease risk factors, symptoms, management, and the association between each domain but also provides educational material. Further educational material and campaigns are required to increase awareness and knowledge about cardiovascular diseases.

Keywords: awareness, cardiovascular diseases, education, prevention, risk factors

Procedia PDF Downloads 110
671 Community Perception towards the Major Drivers for Deforestation and Land Degradation of Choke Afro-alpine and Sub-afro alpine Ecosystem, Northwest Ethiopia

Authors: Zelalem Teshager

Abstract:

The Choke Mountains have several endangered and endemic wildlife species and provide important ecosystem services. Despite their environmental importance, the Choke Mountains are found in dangerous conditions. This raised the need for an evaluation of the community's perception of deforestation and its major drivers and suggested possible solutions in the Choke Mountains of northwestern Ethiopia. For this purpose, household surveys, key informant interviews, and focus group discussions were used. A total sample of 102 informants was used for this survey. A purposive sampling technique was applied to select the participants for in-depth interviews and focus group discussions. Both qualitative and quantitative data analyses were used. Computation of descriptive statistics such as mean, percentages, frequency, tables, figures, and graphs was applied to organize, analyze, and interpret the study. This study assessed smallholder agricultural land expansion, Fuel wood collection, population growth; encroachment, free grazing, high demand of construction wood, unplanned resettlement, unemployment, border conflict, lack of a strong forest protecting system, and drought were the serious causes of forest depletion reported by local communities. Loss of land productivity, Soil erosion, soil fertility decline, increasing wind velocity, rising temperature, and frequency of drought were the most perceived impacts of deforestation. Most of the farmers have a holistic understanding of forest cover change. Strengthening forest protection, improving soil and water conservation, enrichment planting, awareness creation, payment for ecosystem services, and zero grazing campaigns were mentioned as possible solutions to the current state of deforestation. Applications of Intervention measures, such as animal fattening, beekeeping, and fruit production can contribute to decreasing the deforestation causes and improve communities’ livelihood. In addition, concerted efforts of conservation will ensure that the forests’ ecosystems contribute to increased ecosystem services. The major drivers of deforestation should be addressed with government intervention to change dependency on forest resources, income sources of the people, and institutional set-up of the forestry sector. Overall, further reduction in anthropogenic pressure is urgent and crucial for the recovery of the afro-alpine vegetation and the interrelated endangered wildlife in the Choke Mountains.

Keywords: choke afro-alpine, deforestation, drivers, intervention measures, perceptions

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670 Upper Jurassic Foraminiferal Assemblages and Palaeoceanographical Changes in the Central Part of the East European Platform

Authors: Clementine Colpaert, Boris L. Nikitenko

Abstract:

The Upper Jurassic foraminiferal assemblages of the East European Platform have been strongly investigated through the 20th century with biostratigraphical and in smaller degree palaeoecological and palaeobiogeographical purposes. Over the Late Jurassic, the platform was a shallow epicontinental sea that extended from Tethys to the Artic through the Pechora Sea and further toward the northeast in the West Siberian Sea. Foraminiferal assemblages of the Russian Sea were strongly affected by sea-level changes and were controlled by alternated Boreal to Peritethyan influences. The central part of the East European Platform displays very rich and diverse foraminiferal assemblages. Two sections have been analyzed; the Makar'yev Section in the Moscow Depression and the Gorodishi Section in the Yl'yanovsk Depression. Based on the evolution of foraminiferal assemblages, palaeoenvironment has been reconstructed, and sea-level changes have been refined. The aim of this study is to understand palaeoceanographical changes throughout the Oxfordian – Kimmeridgian of the central part of the Russian Sea. The Oxfordian was characterized by a general transgressive event with intermittency of small regressive phases. The platform was connected toward the south with Tethys and Peritethys. During the Middle Oxfordian, opening of a pathway of warmer water from the North-Tethys region to the Boreal Realm favoured the migration of planktonic foraminifera and the appearance of new benthic taxa. It is associated with increased temperature and primary production. During the Late Oxfordian, colder water inputs associated with the microbenthic community crisis may be a response to the closure of this warm-water corridor and the disappearance of planktonic foraminifera. The microbenthic community crisis is probably due to the increased sedimentation rate in the transition from the maximum flooding surface to a second-order regressive event, increasing productivity and inputs of organic matter along with sharp decrease of oxygen into the sediment. It is following during the Early Kimmeridgian by a replacement of foraminiferal assemblages. The almost all Kimmeridgian is characterized by the abundance of many common with Boreal and Subboreal Realm. Connections toward the South began again dominant after a small regressive event recorded during the Late Kimmeridgian and associated with the abundance of many common taxa with Subboreal Realm and Peritethys such as Crimea and Caucasus taxa. Foraminiferal assemblages of the East European Platform are strongly affected by palaeoecological changes and may display a very good model for biofacies typification under Boreal and Subboreal environments. The East European Platform appears to be a key area for the understanding of Upper Jurassic big scale palaeoceanographical changes, being connected with Boreal to Peritethyan basins.

Keywords: foraminifera, palaeoceanography, palaeoecology, upper jurassic

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669 Vagal Nerve Stimulator as a Treatment Approach in CHARGE Syndrome: A Case Report

Authors: Roya Vakili, Lekaa Elhajjmoussa, Barzin Omidi-Shal, Kim Blake

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Objective: The purpose of this case report is to highlight the successful treatment of a patient with Coloboma, Heart defect, Atresia choanae, Retarded growth and development, Genital hypoplasia, Ear anomalies/deafness, (CHARGE syndrome) using a vagal nerve stimulator (VNS). Background: This is the first documented case report, to the authors' best knowledge, for a patient with CHARGE syndrome, epilepsy, autism, and postural orthostatic tachycardia syndrome (POTS) that was successfully treated with an implanted VNS therapeutic device. Methodology: The study is a case report. Results: This is the case of a 24-year-old female patient with CHARGE syndrome (non-random association of anomalies Coloboma, Heart defect, Atresia choanae, Retarded growth and development, Genital hypoplasia, Ear anomalies/deafness) and several other comorbidities including refractory epilepsy, Patent Ductus Arteriosus (PDA) and POTS who had significant improvement of her symptoms after VNS implantation. She was a VNS candidate given her longstanding history of drug-resistant epilepsy and current disposition secondary to CHARGE syndrome. Prior to VNS implantation, she experienced three generalized seizures a year and daily POTS-related symptoms. She was having frequent lightheadedness and syncope spells due to a rapid heart rate and low blood pressure. The VNS device was set to detect a rapid heart rate and send appropriate stimulation anytime the heart rate exceeded 20% of the patient’s normal baseline. The VNS device demonstrated frequent elevated heart rates and concurrent VNS release every 8 minutes in addition to the programmed events. Following VNS installation, the patient became more active, alert, and communicative and was able to verbally communicate with words she was unable to say prior. Her GI symptoms also improved, as she was able to tolerate food better orally in addition to her G and J tube, likely another result of the vagal nerve stimulation. Additionally, the patient’s seizures and POTS-related cardiac events appeared to be well controlled. She had prolonged electroencephalogram (EEG) testing, showing no significant change in epileptiform activity. Improvements in the patient’s disposition are believed to be secondary to parasympathetic stimulation, adequate heart rate control, and GI stimulation, in addition to behavioral changes and other benefits via her implanted VNS. Conclusion: VNS showed promising results in improving the patient's quality of life and managing her diverse symptoms, including dysautonomia, POTs, gastrointestinal mobility, cognitive functioning as well seizure control.

Keywords: autism, POTs, CHARGE, VNS

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668 Raman Tweezers Spectroscopy Study of Size Dependent Silver Nanoparticles Toxicity on Erythrocytes

Authors: Surekha Barkur, Aseefhali Bankapur, Santhosh Chidangil

Abstract:

Raman Tweezers technique has become prevalent in single cell studies. This technique combines Raman spectroscopy which gives information about molecular vibrations, with optical tweezers which use a tightly focused laser beam for trapping the single cells. Thus Raman Tweezers enabled researchers analyze single cells and explore different applications. The applications of Raman Tweezers include studying blood cells, monitoring blood-related disorders, silver nanoparticle-induced stress, etc. There is increased interest in the toxic effect of nanoparticles with an increase in the various applications of nanoparticles. The interaction of these nanoparticles with the cells may vary with their size. We have studied the effect of silver nanoparticles of sizes 10nm, 40nm, and 100nm on erythrocytes using Raman Tweezers technique. Our aim was to investigate the size dependence of the nanoparticle effect on RBCs. We used 785nm laser (Starbright Diode Laser, Torsana Laser Tech, Denmark) for both trapping and Raman spectroscopic studies. 100 x oil immersion objectives with high numerical aperture (NA 1.3) is used to focus the laser beam into a sample cell. The back-scattered light is collected using the same microscope objective and focused into the spectrometer (Horiba Jobin Vyon iHR320 with 1200grooves/mm grating blazed at 750nm). Liquid nitrogen cooled CCD (Symphony CCD-1024x256-OPEN-1LS) was used for signal detection. Blood was drawn from healthy volunteers in vacutainer tubes and centrifuged to separate the blood components. 1.5 ml of silver nanoparticles was washed twice with distilled water leaving 0.1 ml silver nanoparticles in the bottom of the vial. The concentration of silver nanoparticles is 0.02mg/ml so the 0.03mg of nanoparticles will be present in the 0.1 ml nanoparticles obtained. The 25 ul of RBCs were diluted in 2 ml of PBS solution and then treated with 50 ul (0.015mg) of nanoparticles and incubated in CO2 incubator. Raman spectroscopic measurements were done after 24 hours and 48 hours of incubation. All the spectra were recorded with 10mW laser power (785nm diode laser), 60s of accumulation time and 2 accumulations. Major changes were observed in the peaks 565 cm-1, 1211 cm-1, 1224 cm-1, 1371 cm-1, 1638 cm-1. A decrease in intensity of 565 cm-1, increase in 1211 cm-1 with a reduction in 1224 cm-1, increase in intensity of 1371 cm-1 also peak disappearing at 1635 cm-1 indicates deoxygenation of hemoglobin. Nanoparticles with higher size were showing maximum spectral changes. Lesser changes observed in case of 10nm nanoparticle-treated erythrocyte spectra.

Keywords: erythrocytes, nanoparticle-induced toxicity, Raman tweezers, silver nanoparticles

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667 Fabrication of Aluminum Nitride Thick Layers by Modified Reactive Plasma Spraying

Authors: Cécile Dufloux, Klaus Böttcher, Heike Oppermann, Jürgen Wollweber

Abstract:

Hexagonal aluminum nitride (AlN) is a promising candidate for several wide band gap semiconductor compound applications such as deep UV light emitting diodes (UVC LED) and fast power transistors (HEMTs). To date, bulk AlN single crystals are still commonly grown from the physical vapor transport (PVT). Single crystalline AlN wafers obtained from this process could offer suitable substrates for a defect-free growth of ultimately active AlGaN layers, however, these wafers still lack from small sizes, limited delivery quantities and high prices so far.Although there is already an increasing interest in the commercial availability of AlN wafers, comparatively cheap Si, SiC or sapphire are still predominantly used as substrate material for the deposition of active AlGaN layers. Nevertheless, due to a lattice mismatch up to 20%, the obtained material shows high defect densities and is, therefore, less suitable for high power devices as described above. Therefore, the use of AlN with specially adapted properties for optical and sensor applications could be promising for mass market products which seem to fulfill fewer requirements. To respond to the demand of suitable AlN target material for the growth of AlGaN layers, we have designed an innovative technology based on reactive plasma spraying. The goal is to produce coarse grained AlN boules with N-terminated columnar structure and high purity. In this process, aluminum is injected into a microwave stimulated nitrogen plasma. AlN, as the product of the reaction between aluminum powder and the plasma activated N2, is deposited onto the target. We used an aluminum filament as the initial material to minimize oxygen contamination during the process. The material was guided through the nitrogen plasma so that the mass turnover was 10g/h. To avoid any impurity contamination by an erosion of the electrodes, an electrode-less discharge was used for the plasma ignition. The pressure was maintained at 600-700 mbar, so the plasma reached a temperature high enough to vaporize the aluminum which subsequently was reacting with the surrounding plasma. The obtained products consist of thick polycrystalline AlN layers with a diameter of 2-3 cm. The crystallinity was determined by X-ray crystallography. The grain structure was systematically investigated by optical and scanning electron microscopy. Furthermore, we performed a Raman spectroscopy to provide evidence of stress in the layers. This paper will discuss the effects of process parameters such as microwave power and deposition geometry (specimen holder, radiation shields, ...) on the topography, crystallinity, and stress distribution of AlN.

Keywords: aluminum nitride, polycrystal, reactive plasma spraying, semiconductor

Procedia PDF Downloads 268