Search results for: control unit
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 12360

Search results for: control unit

4110 Influence of Salicylic Acid on Yield and Some Physiological Parameters in Chickpea (Cicer arietinum L.)

Authors: Farid Shekari

Abstract:

Salicylic Acid (SA) is a plant hormone that improves some physiological responses of plants under stress conditions. Seeds of two desi type chickpea cultivars, viz., Kaka and Pirooz, primed with 250, 500, 750, and 1000 μM of SA and a group of seeds without any treating (as control) were evaluated under rain fed conditions. Seed priming in both cultivars led to higher efficiency compare to non-primed treatments. In general, seed priming with 500 and 750 μM of SA had appropriate effects; however the cultivars responses were different in this regard. Kaka showed better performance both in primed and non-primed seed than Pirooz. Results of this study revealed that not only yield quantity but also yield quality, as seed protein amounts, could positively affect by SA treatments. It seems that SA by enhancing of soluble sugars and proline amounts enhanced total water potential (ψ) and RWC. The increment in RWC led to rose of chlorophyll content of plants chlorophyll stability. In general, SA increased water use efficiency, both in biologic and seed yield base, and drought tolerance of chickpea plants. HI was a little decreased in SA treatments and it shows that SA more effective in biomass production than seed yield.

Keywords: chlorophyll, harvest index, proline, seed protein, soluble sugar, water use efficiency, yield component

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4109 Antioxidative Effect of Bauhinia acuminata Water Extract Consumption in Rat

Authors: Amornnat Thuppia, Pornrut Rabintossaporn, Suphaket Saenthaweesuk, Nuntiya Somparn

Abstract:

The aim of this present study was to determine the antioxidant effects and its mechanism of aqueous leaves extract of Bauhinia acuminata (BA) in rat. The extract was screened for its phytochemical contents and antioxidant activity in vitro. Moreover, the extract was studied in rats to evaluate its effects in vivo. Rats were orally administered with the extract at the dose of 50, 100 and 200 mg/kg for 28 days. Phytochemical screening of plant extracts showed the presence of saponin, alkaloid, cardiac glycosides, flavonoids, tannin and steroid compounds. The extract contained phenolic compounds 53.36 ± 1.01 mg of gallic acid equivalents per gram BA extract. The free radical scavenging activity assessed by DPPH assay gave IC50 of 44.47 ± 2.83 µg/mL, which is relatively lower than that of BHT with IC50 of 12.34 ± 1.14µg/mL. In the animals, the extract was well tolerated by the animals throughout the 28 days of study as shown by normal serum levels AST, ALP, ALT, BUN and Cr as well as normal histology of liver and pancreatic and kidney tissue. Significantly, reduction of serum oxidative stress markers malondialdehyde (MDA) was found in rat treated with BA extract compared with control. Taken together, this study provides evidence that Bauhinia acuminata (BA) exhibits direct antioxidant properties and induces cytoprotective enzyme in vivo.

Keywords: Bauhinia acuminata, antioxidant, malondialdehyde (MDA), oxidative marker

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4108 Study and Calibration of Autonomous UAV Systems with Thermal Sensing Allowing Screening of Environmental Concerns

Authors: Raahil Sheikh, Abhishek Maurya, Priya Gujjar, Himanshu Dwivedi, Prathamesh Minde

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UAVs have been an initial member of our environment since it's the first used by Austrian warfare in Venice. At that stage, they were just pilotless balloons equipped with bombs to be dropped on enemy territory. Over time, technological advancements allowed UAVs to be controlled remotely or autonomously. This study shall mainly focus on the intensification of pre-existing manual drones equipping them with a variety of sensors and making them autonomous, and capable, and purposing them for a variety of roles, including thermal sensing, data collection, tracking creatures, forest fires, volcano detection, hydrothermal studies, urban heat, Island measurement, and other environmental research. The system can also be used for reconnaissance, research, 3D mapping, and search and rescue missions. This study mainly focuses on automating tedious tasks and reducing human errors as much as possible, reducing deployment time, and increasing the overall efficiency, efficacy, and reliability of the UAVs. Creation of a comprehensive Ground Control System UI (GCS) enabling less trained professionals to be able to use the UAV with maximum potency. With the inclusion of such an autonomous system, artificially intelligent paths and environmental gusts and concerns can be avoided.

Keywords: UAV, drone, autonomous system, thermal imaging

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4107 Risky Driving Behavior among Bus Driver in Jakarta

Authors: Ratri A. Benedictus, Felicia M. Yolanda

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Public transport is a crucial issue for capital city in developing country, such as Jakarta. Inadequate number and low quality of public transport services resulting personal vehicles as the main option. As a result, traffic jams are getting worse in Jakarta. The low quality of public transport, particularly buses, compounded by the risk behavior of the driver. Traffic accidents involving public bus in Jakarta were often the case, even result in fatality. The purpose of this study is to get a description of risk behavior among the public bus drivers in Jakarta. 132 bus drivers become respondent of this study. Risky Driving Behavior scale of Dorn were used. Data were analyzed using descriptive statistics. 51.5% of respondents felt often showing risky behavior while on driving. The highest type of risky driving behavior is still using the unsafe bus (62%). Followed by trespass the bus line (30%), over speed (21%), violate the road signs (15%) and driving with unhealthy physical condition (4%). Results of this study suggested that high understanding of the bus drivers on their risk behaviors have not lead to the emergence of safe driving behavior. Therefore, together with technical engineering and instrumentation work intervention over this issue, psychological aspects also need to be considered, such as: risk perception, safety attitude,safety culture, locus of control and Fatalism.

Keywords: bus driver, psychological factors, public transportation, risky driving behavior

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4106 Effects of Delphinidin on Lipid Metabolism in HepG2 Cells and Diet-Induced Obese Mice

Authors: Marcela Parra-Vargas, Ana Sandoval-Rodriguez, Roberto Rodriguez-Echevarria, Jose Dominguez-Rosales, Juan Armendariz-Borunda

Abstract:

Non-alcoholic fatty liver disease (NAFLD) is characterized by an excess of hepatic lipids, and it is to author’s best knowledge, the most prevalent chronic liver disorder. Anthocyanin-rich food consumption is linked to health benefits in metabolic disorders associated with obesity and NAFLD, although the precise functional role of anthocyanidin delphinidin (Dp) has yet to be established. The aim of this study was to investigate the effect of the Dp in NAFLD metabolic alterations by evaluating prevention or amelioration of hepatic lipid accumulation, as well as molecular mechanisms in two experimental obesity-related models of NALFD. In vitro: HepG2 cells were incubated with sodium palmitate (PA, 1 mM) to induce lipotoxic damage, and concomitantly treated with Dp (180 uM) for 24 h. Subsequently, total lipid accumulation was measured by colorimetric staining with Oil Red O, and total intrahepatic triglycerides were determined by an enzymatic assay. To assess molecular mechanisms, cells were pre-treated with PA for 24 h and then exposed to Dp for 1 h. In vivo: four-week-old male C57BL/6Nhsd mice were allocated in two main groups. Mice were fed with standard diet (control) or high-fat and high-carbohydrate diet (45% fat, HFD) for 16 wk to induce NAFLD. Then HFD was divided into subgroups: one treated orally with Dp (15 mg/kg bw, HFD-Dp) every day for 4 wk, while HFD group treated with vehicle (DMSO). Weight and fasting glucose were recorded weekly, while dietary ingestion was measured daily. Insulin tolerance test was performed at the end of treatment. Liver histology was evaluated with H&E and Masson’s trichrome stain. RT-PCR was used to evaluate gene expression and Western Blot to determine levels of protein in both experimental models. Parametric data were analyzed with one-way ANOVA and Tukey’s post-hoc test. Kruskal-Wallis and Mann-Whitney U test for non-parametric data, and P < 0.5 were considered significant. Dp prevented hepatic lipid accumulation by PA in HepG2 hepatocytes. Furthermore, Dp down-regulated gene expression of SREBP1c, FAS, and CPT1a without modifying AMPK phosphorylation levels. In vivo, Dp oral administration did not ameliorate lipid metabolic alterations raised by HFD. Adiposity, dietary ingestion, fasting glucose, and insulin sensitivity after Dp treatment remained similar to HFD group. Histological analysis showed hepatic damage in HFD groups and no differences between HFD and HFD-Dp groups were found. Hepatic gene expression of ACC and FAS were not altered by HFD. SREBP1c was similar in both HFD and HFD-Dp groups. No significant changes were observed in SREBP1c, ACC, and FAS adipose tissue gene expression by HFD or Dp treatment. Additionally, immunoblotting analysis revealed no changes in pathway SIRT1-LKB-AMPK and PPAR alpha by both HFD groups compared to control. In conclusion, the antioxidant Dp may provoke beneficial effects in the prevention of hepatic lipid accumulation. Nevertheless, the oral dose administrated in mice that simulated the total intake of anthocyanins consumed daily by humans has no effect as a treatment on hepatic lipid metabolic alterations and histological abnormalities associated with exposure to chronic HFD. A healthy lifestyle with regular intake of antioxidants such as anthocyanins may prevent metabolic alterations in NAFLD.

Keywords: anthocyanins, antioxidants, delphinidin, non-alcoholic fatty liver disease, obesity

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4105 Epidemiological, Clinical, Histopathological Profile and Management of Breast Cancer at Kinshasa University Clinics

Authors: Eddy K. Mukadi

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This work is a documentary and descriptive study devoted to the epidemiological, clinical, histopathological and therapeutic profile of breast cancer deals with the department of gynecology and obstetrics of the university clinics of Kinshasa during the period from 1 January 2014 to 31 December 2014. We have identified 56 cases of breast cancer. These cancers accounted for 45.2% of gynecological mammary cancers. The youngest in our series was 18 years old while the oldest was 74 years old; And the mean age of these patients was 43.4 years and mostly multiparous (35.7%). Brides (60.7%) and bachelors (26.8%) were the most affected by breast cancer. The reasons for consultation were dominated by nodules in the breast (48.2%) followed by pain (35.7%) and nipple discharge (14.3%). In 89.2% of the cases, it was the advanced clinical stage (stage 3 and 4) and the infiltrating ductal carcinoma was the most frequent histological type (75%) The malignant tumor was mainly in the left breast (55.3%), and chemotherapy with hormone therapy and patey was the most convenient treatment (42.8%), while patey mastectomy was performed in 12.5% of patients. Because of the high incidence of breast cancer identified in our study, some preventive measures must be taken into account to address this public health problem, including breast autopalpation once a month, Early detection system development of a national breast cancer policy and the implementation of a national breast cancer control program.

Keywords: breast cancer, histopathological profile, epidemiological profile, Kinshasa

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4104 Noninvasive Brain-Machine Interface to Control Both Mecha TE Robotic Hands Using Emotiv EEG Neuroheadset

Authors: Adrienne Kline, Jaydip Desai

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Electroencephalogram (EEG) is a noninvasive technique that registers signals originating from the firing of neurons in the brain. The Emotiv EEG Neuroheadset is a consumer product comprised of 14 EEG channels and was used to record the reactions of the neurons within the brain to two forms of stimuli in 10 participants. These stimuli consisted of auditory and visual formats that provided directions of ‘right’ or ‘left.’ Participants were instructed to raise their right or left arm in accordance with the instruction given. A scenario in OpenViBE was generated to both stimulate the participants while recording their data. In OpenViBE, the Graz Motor BCI Stimulator algorithm was configured to govern the duration and number of visual stimuli. Utilizing EEGLAB under the cross platform MATLAB®, the electrodes most stimulated during the study were defined. Data outputs from EEGLAB were analyzed using IBM SPSS Statistics® Version 20. This aided in determining the electrodes to use in the development of a brain-machine interface (BMI) using real-time EEG signals from the Emotiv EEG Neuroheadset. Signal processing and feature extraction were accomplished via the Simulink® signal processing toolbox. An Arduino™ Duemilanove microcontroller was used to link the Emotiv EEG Neuroheadset and the right and left Mecha TE™ Hands.

Keywords: brain-machine interface, EEGLAB, emotiv EEG neuroheadset, OpenViBE, simulink

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4103 The Environmental Effects of Amalgam Tooth Fillings

Authors: Abdulsalam I. Rafida, Abdulhmid M. Alkout, Abdultif M. Alroba

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This study investigates the heavy metal content in the saliva of persons with amalgam tooth fillings. For this purpose, samples of saliva have been collected based on two factors i.e. the number of amalgam fillings in the mouth (one, two or three fillings), and the time factor i.e. the time since the fillings have been in place (less than a year and more than a year). Samples of saliva have also been collected from persons with no amalgam tooth fillings for control. The samples that have been collected so far, have been examined for the basic heavy metal content featuring amalgam, which include mercury (Hg) and silver (Ag). However, all the above mentioned elements have been detected in the samples of saliva of the persons with amalgam tooth fillings, though with varying amounts depending on the number of fillings. Thus, for persons with only one filling the average quantities were found to be 0.00061 ppm and 0.033 ppm for Hg and Ag respectively. On the other hand for persons with two fillings the average quantities were found to be 0.0012 ppm and 0.029 ppm for each of the two elements respectively. However, in order to understand the chemical reactions associated with amalgam tooth fillings in the mouth, the material have been treated outside the mouth using some nutrient media. Those media included drinking water, fizzy drinks and hot tea. All three media have been found to contain the three elements after amalgam treatment. Yet, the fizzy drink medium was found to contain the highest levels of those elements.

Keywords: amalgam, mercury, silver, fizzy drinks, media

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4102 The Effect of Extremely Low Frequency Magnetic Field on Rats Brain

Authors: Omar Abdalla, Abdelfatah Ahmed, Ahmed Mustafa, Abdelazem Eldouma

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The purpose of this study is evaluating the effect of extremely low frequency magnetic field on Waster rats brain. The number of rats used in this study were 25, which were divided into five groups, each group containing five rats as follows: Group 1: The control group which was not exposed to energized field; Group 2: Rats were exposed to a magnetic field with an intensity of 0.6 mT (2 hours/day); Group 3: Rats were exposed to a magnetic field of 1.2 mT (2 hours/day); Group4: Rats were exposed to a magnetic field of 1.8 mT (2 hours/day); Group 5: Rats were exposed to a magnetic field of 2.4 mT (2 hours/day) and all groups were exposed for seven days, by designing a maze and calculating the time average for arriving to the decoy at special conditions. We found the time average before exposure for the all groups was G2=330 s, G3=172 s, G4=500 s and G5=174 s, respectively. We exposed all groups to ELF-MF and measured the time and we found: G2=465 s, G3=388 s, G4=501 s, and G5=442 s. It was observed that the time average increased directly with field strength. Histological samples of frontal lop of brain for all groups were taken and we found lesion, atrophy, empty vacuoles and disorder choroid plexus at frontal lope of brain. And finally we observed the disorder of choroid plexus in histological results and Alzheimer's symptoms increase when the magnetic field increases.

Keywords: nonionizing radiation, biophysics, magnetic field, shrinkage

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4101 Blogging vs Paper-and-Pencil Writing: Evidences from an Iranian Academic L2 Setting

Authors: Mehran Memari, Bita Asadi

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Second language (L2) classrooms in academic contexts usually consist of learners with diverse L2 proficiency levels. One solution for managing such heterogeneous classes and addressing individual needs of students is to improve learner autonomy by using technological innovations such as blogging. The focus of this study is on investigating the effects of blogging on improving the quality of Iranian university students' writings. For this aim, twenty-six Iranian university students participated in the study. Students in the experimental group (n=13) were required to blog daily while the students in the control group (n=13) were asked to write a daily schedule using paper and pencil. After a 3-month period of instruction, the five last writings of the students from both groups were rated by two experienced raters. Also, students' attitudes toward the traditional method and blogging were surveyed using a questionnaire and a semi-structured interview. The research results showed evidences in favor of the students who used blogging in their writing program. Also, although students in the experimental group found blogging more demanding than the traditional method, they showed an overall positive attitude toward the use of blogging as a way of improving their writing skills. The findings of the study have implications for the incorporation of computer-assisted learning in L2 academic contexts.

Keywords: blogging, computer-assisted learning, paper and pencil, writing

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4100 Sustainable Engineering: Synergy of BIM and Environmental Assessment Tools in Hong Kong Construction Industry

Authors: Kwok Tak Kit

Abstract:

The construction industry plays an important role in environmental and carbon emissions as it consumes a huge amount of natural resources and energy. Sustainable engineering involves the process of planning, design, procurement, construction and delivery in which the whole building and construction process resulting from building and construction can be effectively and sustainability managed to achieve the use of natural resources. Implementation of sustainable technology development and innovation, adoption of the advanced construction process and facilitate the facilities management to implement the energy and waste control more accurately and effectively. Study and research in the relationship of BIM and environment assessment tools lack a clear discussion. In this paper, we will focus on the synergy of BIM technology and sustainable engineering in the AEC industry and outline the key factors which enhance the use of advanced innovation, technology and method and define the role of stakeholders to achieve zero-carbon emission toward the Paris Agreement to limit global warming to well below 2ᵒC above pre-industrial levels. A case study of the adoption of Building Information Modeling (BIM) and environmental assessment tools in Hong Kong will be discussed in this paper.

Keywords: sustainability, sustainable engineering, BIM, LEED

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4099 Optimizing the Elevated Nitritation for Autotrophic/Heterotrophic Denitritation in CSTR by Treating Livestock Wastewater

Authors: Hammad Khan, Wookeun Bae

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The objective of this study was to optimize and control the highly loaded and efficient nitrite production having suitability for autotrophic and heterotrophic denitritation. A lab scale CSTR for partial and full nitritation was operated to treat the livestock manure digester liquor having an ammonium concentration of ~2000 mg-NH4+-N/L and biodegradable contents of ~0.8 g-COD/L. The experiments were performed at 30°C, pH: 8.0 DO: 1.5 mg/L and SRT ranging from 7-20 days. After 125 days operation, >95% nitrite buildup having the ammonium loading rate of ~3.2 kg-NH4+-N/m3-day was seen with almost complete ammonium conversion. On increasing the loading rate further (i.e. from 3.2-6.2 kg-NH4+-N/m3-day), stability of the system remained unaffected. On decreasing the pH from 8 to7.5 and further 7.2, removal rate can be easily controlled as 95%, 75% and even 50%. Results demonstrated that nitritation stability and desired removal rates are controlled by a balance of simultaneous inhibition by FA and FNA, pH affect and DO limitation. These parameters proved to be effective even to produce an appropriate influent for anammox. In addition, a mathematical model, identified through the occurring biological reactions, is proposed to optimize the full and partial nitritation process. The proposed model presents relationship between pH, ammonium and produced nitrite for full and partial nitritation under the varying concentrations of DO, and simultaneous inhibition by FA and FNA.

Keywords: stable nitritation, high loading, autrophic denitritation, hetrotrophic denitritation

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4098 Preharvest and Postharvest Factors Influencing Resveratrol, Myricetin and Quercetin Content of Wine

Authors: Mariam Khomasuridze, Nino Chkhartishvili, Irma Chanturia

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The influence of preharvest and postharvest factors on resveratrol, myricetin and quercetin content of wine was studied during the experiment. The content of cis and trans resveratrol, myricetin and quercetin were analyzed by HPLC. In frame of experiment, the various factors affecting on wine composition were researched: variety, climate, viticulture practices, grape maturity, harvesting methods and wine making techniques. The results have shown that varietal potential and amount of yield play the most important role in formation of antioxidant compounds. Based on achieved results, the usage of medium roast oak chips protects resveratrol, myricetin, and quercetin from coagulation and precipitation. Compared to the control samples, the wines, produced by addition of oak chips were approximately four times richer with these antioxidant compounds. The retention of resveratrol was lowered with 45 % in wines, producing in Qvevri by Georgian traditional technology without controlling temperature during fermentation. The opposite effects in case of myricetin, quercetin and total phenolics content were determined. Their concentrations were higher with 56-78%, then in the fermented tank at 22 -25 °C. As the result of the experiment, the optimal technology scheme of wine was worked out, reached by biologically active compounds: resveratrol, myricetin, and quercetin.

Keywords: resveratrol, miricetin, quercetin, wine

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4097 Geochemical Evaluation of Metal Content and Fluorescent Characterization of Dissolved Organic Matter in Lake Sediments

Authors: Fani Sakellariadou, Danae Antivachis

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Purpose of this paper is to evaluate the environmental status of a coastal Mediterranean lake, named Koumoundourou, located in the northeastern coast of Elefsis Bay, in the western region of Attiki in Greece, 15 km far from Athens. It is preserved from ancient times having an important archaeological interest. Koumoundourou lake is also considered as a valuable wetland accommodating an abundant flora and fauna, with a variety of bird species including a few world’s threatened ones. Furthermore, it is a heavily modified lake, affected by various anthropogenic pollutant sources which provide industrial, urban and agricultural contaminants. The adjacent oil refineries and the military depot are the major pollution providers furnishing with crude oil spills and leaks. Moreover, the lake accepts a quantity of groundwater leachates from the major landfill of Athens. The environmental status of the lake results from the intensive land uses combined with the permeable lithology of the surrounding area and the existence of karstic springs which discharge calcareous mountains. Sediment samples were collected along the shoreline of the lake using a Van Veen grab stainless steel sampler. They were studied for the determination of the total metal content and the metal fractionation in geochemical phases as well as the characterization of the dissolved organic matter (DOM). These constituents have a significant role in the ecological consideration of the lake. Metals may be responsible for harmful environmental impacts. The metal partitioning offers comprehensive information for the origin, mode of occurrence, biological and physicochemical availability, mobilization and transport of metals. Moreover, DOM has a multifunctional importance interacting with inorganic and organic contaminants leading to biogeochemical and ecological effects. The samples were digested using microwave heating with a suitable laboratory microwave unit. For the total metal content, the samples were treated with a mixture of strong acids. Then, a sequential extraction procedure was applied for the removal of exchangeable, carbonate hosted, reducible, organic/sulphides and residual fractions. Metal content was determined by an ICP-MS (Perkin Elmer, ICP MASS Spectrophotometer NexION 350D). Furthermore, the DOM was removed via a gentle extraction procedure and then it was characterized by fluorescence spectroscopy using a Perkin-Elmer LS 55 luminescence spectrophotometer equipped with the WinLab 4.00.02 software for data processing (Agilent, Cary Eclipse Fluorescence). Mono dimensional emission, excitation, synchronous-scan excitation and total luminescence spectra were recorded for the classification of chromophoric units present in the aqueous extracts. Total metal concentrations were determined and compared with those of the Elefsis gulf sediments. Element partitioning showed the anthropogenic sources and the contaminant bioavailability. All fluorescence spectra, as well as humification indices, were evaluated in detail to find out the nature and origin of DOM. All the results were compared and interpreted to evaluate the environmental quality of Koumoundourou lake and the need for environmental management and protection.

Keywords: anthropogenic contaminant, dissolved organic matter, lake, metal, pollution

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4096 Klotho Level as a Marker of Low Bone Mineral Density in Egyptian Sickle Cell Disease Patients

Authors: Mona Hamdy, Iman Shaheen, Hadeel Seif Eldin, Basma Ali, Omnia Abdeldayem

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Summary: Bone involvement of sickle cell disease (SCD) patients varies from acute clinical manifestations of painful vaso-occlusive crises or osteomyelitis to more chronic affection of bone mineral density (BMD) and debilitating osteonecrosis and osteoporosis. Secreted klotho protein is involved in calcium (Ca) reabsorption in the kidney. This study aimed to measure serum klotho levels in children with SCD to determine the possibility of using it as a marker of low BMD in children with SCD in correlation with a dual-energy radiograph absorptiometry scan. This study included 60 sickle disease patients and 30 age-matched and sex-matched control participants without SCD. A highly statistically significant difference was found between patients with normal BMD and those with low BMD, with serum Ca and klotho levels being lower in the latter group. Klotho serum level correlated positively with both serum Ca and BMD. Serum klotho level showed 94.9% sensitivity and 95.2% specificity in the detection of low BMD. Both serum Ca and klotho serum levels may be useful markers for detection of low BMD related to SCD with high sensitivity and specificity; however, klotho may be a better indicator as it is less affected by the nutritional and endocrinal status of patients or by intake of Ca supplements.

Keywords: sickle cell disease, BMD, osteoporosis, DEXA, klotho

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4095 Genetic Diversity of Exon-20 of the IIS6 of the Voltage Gated Sodium Channel Gene from Pyrethroid Resistant Anopheles Mosquitoes in Sudan Savannah Region of Jigawa State

Authors: Asma'u Mahe, Abdullahi A. Imam, Adamu J. Alhassan, Nasiru Abdullahi, Sadiya A. Bichi, Nura Lawal, Kamaluddeen Babagana

Abstract:

Malaria is a disease with global health significance. It is caused by parasites and transmitted by Anopheles mosquitoes. Increase in insecticide resistance threatens the disease vector control. The strength of selection pressure acting on a mosquito population in relation to insecticide resistance can be assess by determining the genetic diversity of a fragment spanning exon- 20 of IIS6 of the voltage gated sodium channel (VGSC). Larval samples reared to adulthood were identified and kdr (knock down resistance) profile was determined. The DNA sequences were used to assess the patterns of genetic differentiation by determining the levels of genetic variability between the Anopheles mosquitoes. Genetic differentiation of the Anopheles mosquitoes based on a portion of the voltage gated sodium channel gene was obtained. Polymorphisms were detected; sequence variation and analysis were presented as a phylogenetic tree. Phylogenetic tree of VGSC haplotypes was constructed for samples of the Anopheles mosquitoes using the maximum likelihood method in MEGA 6.0 software. DNA sequences were edited using BioEdit sequence editor. The edited sequences were aligned with reference sequence (Kisumu strain). Analyses were performed as contained in dnaSP 5.10. Results of genetic parameters of polymorphism and haplotype reconstruction were presented in count. Twenty sequences were used for the analysis. Regions selected were 1- 576, invariable (monomorphic) sites were 460 while variable (polymorphic) sites were 5 giving the number of total mutations observed in this study. Mutations obtained from the study were at codon 105: TTC- Phenylalanine replaces TCC- Serine, codon 513: TAG- Termination replaces TTG- Leucine, codon 153, 300 and 553 mutations were non-synonymous. From the constructed phylogenetic tree, some groups were shown to be closer with Exon20Gambiae Kisumu (Reference strain) having some genetic distance, while 5-Exon20Gambiae-F I13.ab1, 18-Exon20Gambiae-F C17.ab1, and 2-Exon20Gambiae-F C13.ab1 clustered together genetically differentiated away from others. Mutations observed in this study can be attributed to the high insecticide resistance profile recorded in the study areas. Haplotype networks of pattern of genetic variability and polymorphism for the fragment of the VGSC sequences of sampled Anopheles mosquitoes revealed low haplotypes for the present study. Haplotypes are set of closely linked DNA variation on X-chromosome. Haplotypes were scaled accordingly to reflect their respective frequencies. Low haplotype number, four VGSC-1014F haplotypes were observed in this study. A positive association was previously established between low haplotype number of VGSC diversity and pyrethroid resistance through kdr mechanism. Significant values at (P < 0.05) of Tajima D and Fu and Li D’ were observed for some of the results indicating possible signature of positive selection on the fragment of VGSC in the study. This is the first report of VGSC-1014F in the study site. Based on the results, the mutation was present in low frequencies. However, the roles played by the observed mutations need further investigation. Mutations, environmental factors among others can affect genetic diversity. The study area has recorded increase in insecticide resistance that can affect vector control in the area. This finding might affect the efforts made against malaria. Sequences were deposited in GenBank for Accession Number.

Keywords: anopheles mosquitoes, insecticide resistance, kdr, malaria, voltage gated sodium channel

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4094 Solar and Galactic Cosmic Ray Impacts on Ambient Dose Equivalent Considering a Flight Path Statistic Representative to World-Traffic

Authors: G. Hubert, S. Aubry

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The earth is constantly bombarded by cosmic rays that can be of either galactic or solar origin. Thus, humans are exposed to high levels of galactic radiation due to altitude aircraft. The typical total ambient dose equivalent for a transatlantic flight is about 50 μSv during quiet solar activity. On the contrary, estimations differ by one order of magnitude for the contribution induced by certain solar particle events. Indeed, during Ground Level Enhancements (GLE) event, the Sun can emit particles of sufficient energy and intensity to raise radiation levels on Earth's surface. Analyses of GLE characteristics occurring since 1942 showed that for the worst of them, the dose level is of the order of 1 mSv and more. The largest of these events was observed on February 1956 for which the ambient dose equivalent rate is in the orders of 10 mSv/hr. The extra dose at aircraft altitudes for a flight during this event might have been about 20 mSv, i.e. comparable with the annual limit for aircrew. The most recent GLE, occurred on September 2017 resulting from an X-class solar flare, and it was measured on the surface of both the Earth and Mars using the Radiation Assessment Detector on the Mars Science Laboratory's Curiosity Rover. Recently, Hubert et al. proposed a GLE model included in a particle transport platform (named ATMORAD) describing the extensive air shower characteristics and allowing to assess the ambient dose equivalent. In this approach, the GCR is based on the Force-Field approximation model. The physical description of the Solar Cosmic Ray (i.e. SCR) considers the primary differential rigidity spectrum and the distribution of primary particles at the top of the atmosphere. ATMORAD allows to determine the spectral fluence rate of secondary particles induced by extensive showers, considering altitude range from ground to 45 km. Ambient dose equivalent can be determined using fluence-to-ambient dose equivalent conversion coefficients. The objective of this paper is to analyze the GCR and SCR impacts on ambient dose equivalent considering a high number statistic of world-flight paths. Flight trajectories are based on the Eurocontrol Demand Data Repository (DDR) and consider realistic flight plan with and without regulations or updated with Radar Data from CFMU (Central Flow Management Unit). The final paper will present exhaustive analyses implying solar impacts on ambient dose equivalent level and will propose detailed analyses considering route and airplane characteristics (departure, arrival, continent, airplane type etc.), and the phasing of the solar event. Preliminary results show an important impact of the flight path, particularly the latitude which drives the cutoff rigidity variations. Moreover, dose values vary drastically during GLE events, on the one hand with the route path (latitude, longitude altitude), on the other hand with the phasing of the solar event. Considering the GLE occurred on 23 February 1956, the average ambient dose equivalent evaluated for a flight Paris - New York is around 1.6 mSv, which is relevant to previous works This point highlights the importance of monitoring these solar events and of developing semi-empirical and particle transport method to obtain a reliable calculation of dose levels.

Keywords: cosmic ray, human dose, solar flare, aviation

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4093 Platooning Method Using Dynamic Correlation of Destination Vectors in Urban Areas

Authors: Yuya Tanigami, Naoaki Yamanaka, Satoru Okamoto

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Economic losses due to delays in traffic congestion regarding urban transportation networks have become a more serious social problem as traffic volume increases. Platooning has recently been attracting attention from many researchers to alleviate traffic jams, especially on the highway. On highways, platooning can have positive effects, such as reducing inter-vehicular distance and reducing air resistance. However, the impacts of platooning on urban roads have not been addressed in detail since traffic lights may break the platoons. In this study, we propose a platooning method using L2 norm and cosine similarity to form a platoon with highly similar routes. Also, we investigate the sorting method within a platoon according to each vehicle’s straightness. Our proposed sorting platoon method, which uses two lanes, eliminates Head of Line Blocking at the intersection and improves throughput at intersections. This paper proposes a cyber-physical system (CPS) approach to collaborative urban platoon control. We conduct simulations using the traffic simulator SUMO and the road network, which imitates Manhattan Island. Results from the SUMO confirmed that our method shortens the average travel time by 10-20%. This paper shows the validity of forming a platoon based on destination vectors and sorting vehicles within a platoon.

Keywords: CPS, platooning, connected car, vector correlation

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4092 Aphrodisiac Activity of Ethanolic Extract of Ionidium Suffruticosum in Male Rats

Authors: D. Satheesh Kumar, K. S. Lakshmi, V. J. Vishnu Varthan

Abstract:

Background: Aphrodisiacs are the substances which are used to increase sexual activity and help in fertility. Infertility is a worldwide medical and social problem. Ionidium suffruticosum has an extensive ethnomedical history of use as a traditional remedy for reproductive impairments. Hence, this study was conducted to study the aphrodisiac properties of Ionidium suffruticosum by observing the sexual behavior of male rats. Methods: The ethanolic extract of whole plant of Ionidium suffruticosum (EEIS) at the dose of 200 mg/kg and sildenafil citrate at the dose of 5 mg/kg were administered to the male rats. Mount latency (ML), intromission latency (IL), ejaculation latency (EL), mounting frequency (MF), intromission frequency (IF), ejaculation frequency (EF) and post-ejaculatory interval (PEI) were the parameters observed before and during the sexual behaviour study at days 0, 10, 20, 30, and 40. Results: The ethanolic extract of roots of Ionidium suffruticosum reduced significantly ML, IL, EL and PEI (p<0.05). There was statistically increase in MF, IF and EF (p<0.05) compared to control following treatment with ethanolic extract of Ionidium suffruticosum. These effects were observed in sexually active and inactive male rats. Conclusion: Present findings provide experimental evidence that the crude extract of Ionidium suffruticosum, used as a traditional remedy, possesses aphrodisiac properties.

Keywords: Ionidium suffruticosum, aphrodisiac, sexual behavior, ethanolic extract

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4091 Development of Geo-computational Model for Analysis of Lassa Fever Dynamics and Lassa Fever Outbreak Prediction

Authors: Adekunle Taiwo Adenike, I. K. Ogundoyin

Abstract:

Lassa fever is a neglected tropical virus that has become a significant public health issue in Nigeria, with the country having the greatest burden in Africa. This paper presents a Geo-Computational Model for Analysis and Prediction of Lassa Fever Dynamics and Outbreaks in Nigeria. The model investigates the dynamics of the virus with respect to environmental factors and human populations. It confirms the role of the rodent host in virus transmission and identifies how climate and human population are affected. The proposed methodology is carried out on a Linux operating system using the OSGeoLive virtual machine for geographical computing, which serves as a base for spatial ecology computing. The model design uses Unified Modeling Language (UML), and the performance evaluation uses machine learning algorithms such as random forest, fuzzy logic, and neural networks. The study aims to contribute to the control of Lassa fever, which is achievable through the combined efforts of public health professionals and geocomputational and machine learning tools. The research findings will potentially be more readily accepted and utilized by decision-makers for the attainment of Lassa fever elimination.

Keywords: geo-computational model, lassa fever dynamics, lassa fever, outbreak prediction, nigeria

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4090 Effect of Citric Acid and Clove on Cured Smoked Meat: A Traditional Meat Product

Authors: Esther Eduzor, Charles A. Negbenebor, Helen O. Agu

Abstract:

Smoking of meat enhances the taste and look of meat, it also increases its longevity, and helps preserve the meat by slowing down the spoilage of fat and growth of bacteria. The Lean meat from the forequarter of beef carcass was obtained from the Maiduguri abattoir. The meat was cut into four portions with weight ranging from 525-545 g. The meat was cut into bits measuring about 8 cm in length, 3.5 cm in thickness and weighed 64.5 g. Meat samples were washed, cured with various concentration of sodium chloride, sodium nitrate, citric acid and clove for 30 min, drained and smoked in a smoking kiln at a temperature range of 55-600°C, for 8 hr a day for 3 days. The products were stored at ambient temperature and evaluated microbiologically and organoleptically. In terms of processing and storage there were increases in pH, free fatty acid content, a decrease in water holding capacity and microbial count of the cured smoked meat. The panelists rated control samples significantly (p < 0.05) higher in terms of colour, texture, taste and overall acceptability. The following organisms were isolated and identified during storage: Bacillus specie, Bacillus subtilis, streptococcus, Pseudomonas, Aspergillus niger, Candida and Penicillium specie. The study forms a basis for new product development for meat industry.

Keywords: citric acid, cloves, smoked meat, bioengineering

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4089 Study and Calibration of Autonomous UAV Systems With Thermal Sensing With Multi-purpose Roles

Authors: Raahil Sheikh, Prathamesh Minde, Priya Gujjar, Himanshu Dwivedi, Abhishek Maurya

Abstract:

UAVs have been an initial member of our environment since it's the first used by Austrian warfare in Venice. At that stage, they were just pilotless balloons equipped with bombs to be dropped on enemy territory. Over time, technological advancements allowed UAVs to be controlled remotely or autonomously. This study shall mainly focus on the intensification of pre-existing manual drones equipping them with a variety of sensors and making them autonomous, and capable, and purposing them for a variety of roles, including thermal sensing, data collection, tracking creatures, forest fires, volcano detection, hydrothermal studies, urban heat, Island measurement, and other environmental research. The system can also be used for reconnaissance, research, 3D mapping, and search and rescue missions. This study mainly focuses on automating tedious tasks and reducing human errors as much as possible, reducing deployment time, and increasing the overall efficiency, efficacy, and reliability of the UAVs. Creation of a comprehensive Ground Control System UI (GCS) enabling less trained professionals to be able to use the UAV with maximum potency. With the inclusion of such an autonomous system, artificially intelligent paths and environmental gusts and concerns can be avoided

Keywords: UAV, autonomous systems, drones, geo thermal imaging

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4088 Robot Navigation and Localization Based on the Rat’s Brain Signals

Authors: Endri Rama, Genci Capi, Shigenori Kawahara

Abstract:

The mobile robot ability to navigate autonomously in its environment is very important. Even though the advances in technology, robot self-localization and goal directed navigation in complex environments are still challenging tasks. In this article, we propose a novel method for robot navigation based on rat’s brain signals (Local Field Potentials). It has been well known that rats accurately and rapidly navigate in a complex space by localizing themselves in reference to the surrounding environmental cues. As the first step to incorporate the rat’s navigation strategy into the robot control, we analyzed the rats’ strategies while it navigates in a multiple Y-maze, and recorded Local Field Potentials (LFPs) simultaneously from three brain regions. Next, we processed the LFPs, and the extracted features were used as an input in the artificial neural network to predict the rat’s next location, especially in the decision-making moment, in Y-junctions. We developed an algorithm by which the robot learned to imitate the rat’s decision-making by mapping the rat’s brain signals into its own actions. Finally, the robot learned to integrate the internal states as well as external sensors in order to localize and navigate in the complex environment.

Keywords: brain-machine interface, decision-making, mobile robot, neural network

Procedia PDF Downloads 283
4087 Effect of Peppermint Essential Oil versus a Mixture of Formic and Propionic Acids on Corn Silage Volatile Fatty Acid Score

Authors: Mohsen Danesh Mesgaran, Ali Hodjatpanah Montazeri, Alireza Vakili, Mansoor Tahmasbei

Abstract:

To compare peppermint essential oil versus a mixture of formic and propionic acids a study was conducted to their effects on volatile fatty acid proportion and VFA score of corn silage. Chopped whole crop corn (control) was treated with peppermint essential oil (240 mg kg-1 DM) or a mixture of formic and propionic acids (2:1) at 0.4% of fresh forage weight, and ensiled for 30 days. Then, silage extract was provided and the concentration of each VFA was determined using gas chromatography. The VFA score was calculated according to the patented formula proposed by Dairy One Scientific Committee. The score is calculated based on the positive impact of lactic and acetic acids versus the negative effect of butyric acid to achieve a single value for evaluating silage quality. The essential oil declined pH and increased the concentration of lactic and acetic acids in the silage extract. All corn silages evaluated in this study had a VFA score between 6 through 8. However, silage with peppermint essential oils had lower volatile fatty acids score than those of the other treatments. Both of applied additives caused a significant improvement in silage aerobic stability.

Keywords: peppermint, essential oil, corn silage, VFA (volatile fatty acids)

Procedia PDF Downloads 378
4086 Preparation of Polylactide Nanoparticles by Supercritical Fluid Technology

Authors: Jakub Zágora, Daniela Plachá, Karla Čech Barabaszová, Sylva Holešová, Roman Gábor, Alexandra Muñoz Bonilla, Marta Fernández García

Abstract:

The development of new antimicrobial materials that are not toxic to higher living organisms is a major challenge today. Newly developed materials can have high application potential in biomedicine, coatings, packaging, etc. A combination of commonly used biopolymer polylactide with cationic polymers seems to be very successful in the fight against antimicrobial resistance [1].PLA will play a key role in fulfilling the intention set out in the New Deal announced by the EU commission, as it is a bioplastic that is easily degradable, recyclable, and mass-produced. Also, the development of 3D printing in the context of this initiative, and the actual use of PLA as one of the main materials used for this printing, make the technology around the preparation and modification of PLA quite logical. Moreover, theenvironmentally friendly and energy saving technology like supercritical fluid process (SFP) will be used for their preparation. In a first approach, polylactide nano- and microparticles and structures were prepared by supercritical fluid extraction. The RESS (rapid expansion supercritical fluid solution) method is easier to optimize and shows better particle size control. On the contrary, a highly porous structure was obtained using the SAS (supercritical antisolvent) method. In a second part, the antimicrobial biobased polymer was introduced by SFP.

Keywords: polylactide, antimicrobial polymers, supercritical fluid technology, micronization

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4085 The Effect of Substitution of CaO/MgO and CaO/SrO on in vitro Bioactivity of Sol-Gel Derived Bioactive Glass

Authors: Zeinab Hajifathali, Moghan Amirhosseinian

Abstract:

This study had two main aims: firstly, to determine how the individual substitution of CaO/MgO and CaO/SrO can affect the in vitro bioactivity of sol-gel derived substituted 58S bioactive glass (BG) and secondly to introduce a composition in the 60SiO2–(36-x)CaO–4P2O5–(x)MgO and 60SiO2–(36-x)CaO–4P2O5–(x)SrO quaternary systems (where x= 0, 5, 10 mol.%) with enhanced biocompatibility, alkaline phosphatase (ALP) activity, and more efficient antibacterial activity against MRSA bacteria. Results showed that both magnesium-substituted bioactive glasses (M-BGs) and strontium- substituted bioactive glasses (S-BGs) retarded the Hydroxyapatite (HA) formation. Meanwhile, magnesium had more pronounced effect. The 3-(4, 5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and ALP assays revealed that the presence of moderate amount (5 mol%) of Mg and Sr had a stimulating effect on increasing of both proliferation and differentiation of MC3T3-E1 cells. Live dead and Dapi/actin staining revealed both substitution of CaO/MgO and CaO/SrO resulted in more biocompatibility and stimulation potential of the MC3T3 cells compared with control. Taken together, among all of the synthesized magnesium substituted (MBGs) and strontium substituted (SBGs), the sample 58- BG with 5 mol% CaO/MgO substitution (BG-5M) was considered as a multifunctional biomaterial in bone tissue regeneration field with enhanced biocompatibility, ALP activity as well as the highest antibacterial efficiency against methicillin-resistant Staphylococcus aureus (MRSA) bacteria.

Keywords: apatite, alkaline earth, bioactivity, biomedical applications, Sol-gel

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4084 Ulnar Nerve Changes Associated with Carpal Tunnel Syndrome Not Affecting Median versus Ulnar Comparative Studies

Authors: Emmanuel Kamal Aziz Saba, Sarah Sayed El-Tawab

Abstract:

The present study was conducted to assess the involvement of ulnar sensory and/or motor nerve fibers in patients with carpal tunnel syndrome (CTS) and whether this affects the accuracy of the median versus ulnar comparative tests. The present study included 145 CTS hands and 71 asymptomatic control hands. Clinical examination was done. The following tests were done: Sensory conduction studies: median, ulnar and dorsal ulnar cutaneous nerves; and median versus ulnar digit (D) four sensory comparative study; and motor conduction studies: median nerve, ulnar nerve and median versus ulnar motor comparative study. It was found that 17 CTS hands (11.7%) had ulnar sensory abnormalities in 17 different patients. The median versus ulnar sensory and motor comparative studies were abnormal among all these 17 CTS hands. There were significant negative correlations between median motor latency and both ulnar sensory amplitudes recording D5 and D4. In conclusion, there is ulnar sensory nerve abnormality among CTS patients. This abnormality affects the amplitude of ulnar sensory nerve action potential. This does not affect the median versus ulnar sensory and motor comparative tests accuracy for use in CTS.

Keywords: median nerve, motor comparative study, sensory comparative study, ulnar nerve

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4083 Understanding Nanocarrier Efficacy in Drug Delivery Systems Using Molecular Dynamics

Authors: Maedeh Rahimnejad, Bahman Vahidi, Bahman Ebrahimi Hoseinzadeh, Fatemeh Yazdian, Puria Motamed Fath, Roghieh Jamjah

Abstract:

Introduction: The intensive labor and high cost of developing new vehicles for controlled drug delivery highlights the need for a change in their discovery process. Computational models can be used to accelerate experimental steps and control the high cost of experiments. Methods: In this work, to better understand the interaction of anti-cancer drug and the nanocarrier with the cell membrane, we have done molecular dynamics simulation using NAMD. We have chosen paclitaxel for the drug molecule and dipalmitoylphosphatidylcholine (DPPC) as a natural phospholipid nanocarrier. Results: Next, center of mass (COM) between molecules and the van der Waals interaction energy close to the cell membrane has been analyzed. Furthermore, the simulation results of the paclitaxel interaction with the cell membrane and the interaction of DPPC as a nanocarrier loaded by the drug with the cell membrane have been compared. Discussion: Analysis by molecular dynamics (MD) showed that not only the energy between the nanocarrier and the cell membrane is low, but also the center of mass amount decreases in the nanocarrier and the cell membrane system during the interaction; therefore they show significantly better interaction in comparison to the individual drug with the cell membrane.

Keywords: anti-cancer drug, center of mass, interaction energy, molecular dynamics simulation, nanocarrier

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4082 Failure and Stress Analysis of Super Heater Tubes of a 67 TPH Coke Dry Quenching Boiler

Authors: Subodh N. Patel, Abhijit Pusty, Manashi Adhikary, Sandip Bhattacharyya

Abstract:

The steam superheater (SH) is a coil type heat exchanger which is used to produce superheated steam or to convert the wet steam to dry steam (69.6 kg/cm² and 495°C), generated by a boiler. There were two superheaters in the system, SH I and SH II. SH II is a set of tubes that faces the initial interaction with flue gas at high temperature followed by SH I tubes. After a service life of 2100 hours, a tube in the SH II found to be punctured. Dye penetrant test revealed that out of 50 such tubes, 14 more tubes had severe cracks at a similar location. The failure was investigated in detail. The materials and scale were characterized by optical microscope and advance characterization technique. Scale, observed on fracture surface, was characterized under scanning electron microscope and Raman spectroscopy. Stresses acting on the tubes in working condition were analyzed by finite element method software, ANSYS. Cyclic stresses were observed in the simulation at the same prone location due to restriction in expansion of tubes. Based on scale characterization and stress analysis, it was concluded that the tube failed in thermo-mechanical fatigue. Finally, prevention and control measures were taken to avoid such failure in the future.

Keywords: finite element analysis, oxide scale, superheater tube, thermomechanical fatigue

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4081 Impact of Simulated Brain Interstitial Fluid Flow on the Chemokine CXC-Chemokine-Ligand-12 Release From an Alginate-Based Hydrogel

Authors: Wiam El Kheir, Anais Dumais, Maude Beaudoin, Bernard Marcos, Nick Virgilio, Benoit Paquette, Nathalie Faucheux, Marc-Antoine Lauzon

Abstract:

The high infiltrative pattern of glioblastoma multiforme cells (GBM) is the main cause responsible for the actual standard treatments failure. The tumor high heterogeneity, the interstitial fluid flow (IFF) and chemokines guides GBM cells migration in the brain parenchyma resulting in tumor recurrence. Drug delivery systems emerged as an alternative approach to develop effective treatments for the disease. Some recent studies have proposed to harness the effect CXC-lchemokine-ligand-12 to direct and control the cancer cell migration through delivery system. However, the dynamics of the brain environment on the delivery system remains poorly understood. Nanoparticles (NPs) and hydrogels are known as good carriers for the encapsulation of different agents and control their release. We studied the release of CXCL12 (free or loaded into NPs) from an alginate-based hydrogel under static and indirect perfusion (IP) conditions. Under static conditions, the main phenomena driving CXCL12 release from the hydrogel was diffusion with the presence of strong interactions between the positively charged CXCL12 and the negatively charge alginate. CXCL12 release profiles were independent from the initial mass loadings. Afterwards, we demonstrated that the release could tuned by loading CXCL12 into Alginate/Chitosan-Nanoparticles (Alg/Chit-NPs) and embedded them into alginate-hydrogel. The initial burst release was substantially attenuated and the overall cumulative release percentages of 21%, 16% and 7% were observed for initial mass loadings of 0.07, 0.13 and 0.26 µg, respectively, suggesting stronger electrostatic interactions. Results were mathematically modeled based on Fick’s second law of diffusion framework developed previously to estimate the effective diffusion coefficient (Deff) and the mass transfer coefficient. Embedding the CXCL12 into NPs decreased the Deff an order of magnitude, which was coherent with experimental data. Thereafter, we developed an in-vitro 3D model that takes into consideration the convective contribution of the brain IFF to study CXCL12 release in an in-vitro microenvironment that mimics as faithfully as possible the human brain. From is unique design, the model also allowed us to understand the effect of IP on CXCL12 release in respect to time and space. Four flow rates (0.5, 3, 6.5 and 10 µL/min) which may increase CXCL12 release in-vivo depending on the tumor location were assessed. Under IP, cumulative percentages varying between 4.5-7.3%, 23-58.5%, 77.8-92.5% and 89.2-95.9% were released for the three initial mass loadings of 0.08, 0.16 and 0.33 µg, respectively. As the flow rate increase, IP culture conditions resulted in a higher release of CXCL12 compared to static conditions as the convection contribution became the main driving mass transport phenomena. Further, depending on the flow rate, IP had a direct impact on CXCL12 distribution within the simulated brain tissue, which illustrates the importance of developing such 3D in-vitro models to assess the efficiency of a delivery system targeting the brain. In future work, using this very model, we aim to understand the impact of the different phenomenon occurring on GBM cell behaviors in response to the resulting chemokine gradient subjected to various flow while allowing them to express their invasive characteristics in an in-vitro microenvironment that mimics the in-vivo brain parenchyma.

Keywords: 3D culture system, chemokines gradient, glioblastoma multiforme, kinetic release, mathematical modeling

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