Search results for: systolic blood pressure
3828 Selective Oxidation of 6Mn-2Si Advanced High Strength Steels during Intercritical Annealing Treatment
Authors: Maedeh Pourmajidian, Joseph R. McDermid
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Advanced High Strength Steels are revolutionizing both the steel and automotive industries due to their high specific strength and ability to absorb energy during crash events. This allows manufacturers to design vehicles with significantly increased fuel efficiency without compromising passenger safety. To maintain the structural integrity of the fabricated parts, they must be protected from corrosion damage through continuous hot-dip galvanizing process, which is challenging due to selective oxidation of Mn and Si on the surface of this AHSSs. The effects of process atmosphere oxygen partial pressure and small additions of Sn on the selective oxidation of a medium-Mn C-6Mn-2Si advanced high strength steel was investigated. Intercritical annealing heat treatments were carried out at 690˚C in an N2-5%H2 process atmosphere under dew points ranging from –50˚C to +5˚C. Surface oxide chemistries, morphologies, and thicknesses were determined at a variety of length scales by several techniques, including SEM, TEM+EELS, and XPS. TEM observations of the sample cross-sections revealed the transition to internal oxidation at the +5˚C dew point. EELS results suggested that the internal oxides network was composed of a multi-layer oxide structure with varying chemistry from oxide core towards the outer part. The combined effect of employing a known surface active element as a function of process atmosphere on the surface structure development and the possible impact on reactive wetting of the steel substrates by the continuous galvanizing zinc bath will be discussed.Keywords: 3G AHSS, hot-dip galvanizing, oxygen partial pressure, selective oxidation
Procedia PDF Downloads 3983827 Numerical Investigation of Soft Clayey Soil Improved by Soil-Cement Columns under Harmonic Load
Authors: R. Ziaie Moayed, E. Ghanbari Alamouty
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Deep soil mixing is one of the improvement methods in geotechnical engineering which is widely used in soft soils. This article investigates the consolidation behavior of a soft clay soil which is improved by soil-cement column (SCC) by numerical modeling using Plaxis2D program. This behavior is simulated under vertical static and cyclic load which is applied on the soil surface. The static load problem is the simulation of a physical model test in an axisymmetric condition which uses a single SCC in the model center. The results of numerical modeling consist of settlement of soft soil composite, stress on soft soil and column, and excessive pore water pressure in the soil show a good correspondence with the test results. The response of soft soil composite to the cyclic load in vertical direction also compared with the static results. Also the effects of two variables namely the cement content used in a SCC and the area ratio (the ratio of the diameter of SCC to the diameter of composite soil model, a) is investigated. The results show that the stress on the column with the higher value of a, is lesser compared with the stress on other columns. Different rate of consolidation and excessive pore pressure distribution is observed in cyclic load problem. Also comparing the results of settlement of soil shows higher compressibility in the cyclic load problem.Keywords: area ratio, consolidation behavior, cyclic load, numerical modeling, soil-cement column
Procedia PDF Downloads 1513826 Rapid Atmospheric Pressure Photoionization-Mass Spectrometry (APPI-MS) Method for the Detection of Polychlorinated Dibenzo-P-Dioxins and Dibenzofurans in Real Environmental Samples Collected within the Vicinity of Industrial Incinerators
Authors: M. Amo, A. Alvaro, A. Astudillo, R. Mc Culloch, J. C. del Castillo, M. Gómez, J. M. Martín
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Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) of course comprise a range of highly toxic compounds that may exist as particulates within the air or accumulate within water supplies, soil, or vegetation. They may be created either ubiquitously or naturally within the environment as a product of forest fires or volcanic eruptions. It is only since the industrial revolution, however, that it has become necessary to closely monitor their generation as a byproduct of manufacturing/combustion processes, in an effort to mitigate widespread contamination events. Of course, the environmental concentrations of these toxins are expected to be extremely low, therefore highly sensitive and accurate methods are required for their determination. Since ionization of non-polar compounds through electrospray and APCI is difficult and inefficient, we evaluate the performance of a novel low-flow Atmospheric Pressure Photoionization (APPI) source for the trace detection of various dioxins and furans using rapid Mass Spectrometry workflows. Air, soil and biota (vegetable matter) samples were collected monthly during one year from various locations within the vicinity of an industrial incinerator in Spain. Analytes were extracted and concentrated using soxhlet extraction in toluene and concentrated by rotavapor and nitrogen flow. Various ionization methods as electrospray (ES) and atmospheric pressure chemical ionization (APCI) were evaluated, however, only the low-flow APPI source was capable of providing the necessary performance, in terms of sensitivity, required for detecting all targeted analytes. In total, 10 analytes including 2,3,7,8-tetrachlorodibenzodioxin (TCDD) were detected and characterized using the APPI-MS method. Both PCDDs and PCFDs were detected most efficiently in negative ionization mode. The most abundant ion always corresponded to the loss of a chlorine and addition of an oxygen, yielding [M-Cl+O]- ions. MRM methods were created in order to provide selectivity for each analyte. No chromatographic separation was employed; however, matrix effects were determined to have a negligible impact on analyte signals. Triple Quadrupole Mass Spectrometry was chosen because of its unique potential for high sensitivity and selectivity. The mass spectrometer used was a Sciex´s Qtrap3200 working in negative Multi Reacting Monitoring Mode (MRM). Typically mass detection limits were determined to be near the 1-pg level. The APPI-MS2 technology applied to the detection of PCDD/Fs allows fast and reliable atmospheric analysis, minimizing considerably operational times and costs, with respect other technologies available. In addition, the limit of detection can be easily improved using a more sensitive mass spectrometer since the background in the analysis channel is very low. The APPI developed by SEADM allows polar and non-polar compounds ionization with high efficiency and repeatability.Keywords: atmospheric pressure photoionization-mass spectrometry (APPI-MS), dioxin, furan, incinerator
Procedia PDF Downloads 2083825 Asymptotic Analysis of the Viscous Flow through a Pipe and the Derivation of the Darcy-Weisbach Law
Authors: Eduard Marusic-Paloka
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The Darcy-Weisbach formula is used to compute the pressure drop of the fluid in the pipe, due to the friction against the wall. Because of its simplicity, the Darcy-Weisbach formula became widely accepted by engineers and is used for laminar as well as the turbulent flows through pipes, once the method to compute the mysterious friction coefficient was derived. Particularly in the second half of the 20th century. Formula is empiric, and our goal is to derive it from the basic conservation law, via rigorous asymptotic analysis. We consider the case of the laminar flow but with significant Reynolds number. In case of the perfectly smooth pipe, the situation is trivial, as the Navier-Stokes system can be solved explicitly via the Poiseuille formula leading to the friction coefficient in the form 64/Re. For the rough pipe, the situation is more complicated and some effects of the roughness appear in the friction coefficient. We start from the Navier-Stokes system in the pipe with periodically corrugated wall and derive an asymptotic expansion for the pressure and for the velocity. We use the homogenization techniques and the boundary layer analysis. The approximation derived by formal analysis is then justified by rigorous error estimate in the norm of the appropriate Sobolev space, using the energy formulation and classical a priori estimates for the Navier-Stokes system. Our method leads to the formula for the friction coefficient. The formula involves resolution of the appropriate boundary layer problems, namely the boundary value problems for the Stokes system in an infinite band, that needs to be done numerically. However, theoretical analysis characterising their nature can be done without solving them.Keywords: Darcy-Weisbach law, pipe flow, rough boundary, Navier law
Procedia PDF Downloads 3533824 Molecular Pathogenesis of NASH through the Dysregulation of Metabolic Organ Network in the NASH-HCC Model Mouse Treated with Streptozotocin-High Fat Diet
Authors: Bui Phuong Linh, Yuki Sakakibara, Ryuto Tanaka, Elizabeth H. Pigney, Taishi Hashiguchi
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NASH is an increasingly prevalent chronic liver disease that can progress to hepatocellular carcinoma and now is attracting interest worldwide. The STAM™ model is a clinically-correlated murine NASH model which shows the same pathological progression as NASH patients and has been widely used for pharmacological and basic research. The multiple parallel hits hypothesis suggests abnormalities in adipocytokines, intestinal microflora, and endotoxins are intertwined and could contribute to the development of NASH. In fact, NASH patients often exhibit gut dysbiosis and dysfunction in adipose tissue and metabolism. However, the analysis of the STAM™ model has only focused on the liver. To clarify whether the STAM™ model can also mimic multiple pathways of NASH progression, we analyzed the organ crosstalk interactions between the liver and the gut and the phenotype of adipose tissue in the STAM™ model. NASH was induced in male mice by a single subcutaneous injection of 200 µg streptozotocin 2 days after birth and feeding with high-fat diet after 4 weeks of age. The mice were sacrificed at NASH stage. Colon samples were snap-frozen in liquid nitrogen and stored at -80˚C for tight junction-related protein analysis. Adipose tissue was prepared into paraffin blocks for HE staining. Blood adiponectin was analyzed to confirm changes in the adipocytokine profile. Tight junction-related proteins in the intestine showed that expression of ZO-1 decreased with the progression of the disease. Increased expression of endotoxin in the blood and decreased expression of Adiponectin were also observed. HE staining revealed hypertrophy of adipocytes. Decreased expression of ZO-1 in the intestine of STAM™ mice suggests the occurrence of leaky gut, and abnormalities in adipocytokine secretion were also observed. Together with the liver, phenotypes in these organs are highly similar to human NASH patients and might be involved in the pathogenesis of NASH.Keywords: Non-alcoholic steatohepatitis, hepatocellular carcinoma, fibrosis, organ crosstalk, leaky gut
Procedia PDF Downloads 1593823 Investigation of Processing Conditions on Rheological Features of Emulsion Gels and Oleogels Stabilized by Biopolymers
Authors: M. Sarraf, J. E. Moros, M. C. Sánchez
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Oleogels are self-standing systems that are able to trap edible liquid oil into a tridimensional network and also help to use less fat by forming crystallization oleogelators. There are different ways to generate oleogelation and oil structuring, including direct dispersion, structured biphasic systems, oil sorption, and indirect method (emulsion-template). The selection of processing conditions as well as the composition of the oleogels is essential to obtain a stable oleogel with characteristics suitable for its purpose. In this sense, one of the ingredients widely used in food products to produce oleogels and emulsions is polysaccharides. Basil seed gum (BSG), with the scientific name Ocimum basilicum, is a new native polysaccharide with high viscosity and pseudoplastic behavior because of its high molecular weight in the food industry. Also, proteins can stabilize oil in water due to the presence of amino and carboxyl moieties that result in surface activity. Whey proteins are widely used in the food industry due to available, cheap ingredients, nutritional and functional characteristics such as emulsifier and a gelling agent, thickening, and water-binding capacity. In general, the interaction of protein and polysaccharides has a significant effect on the food structures and their stability, like the texture of dairy products, by controlling the interactions in macromolecular systems. Using edible oleogels as oil structuring helps for targeted delivery of a component trapped in a structural network. Therefore, the development of efficient oleogel is essential in the food industry. A complete understanding of the important points, such as the ratio oil phase, processing conditions, and concentrations of biopolymers that affect the formation and stability of the emulsion, can result in crucial information in the production of a suitable oleogel. In this research, the effects of oil concentration and pressure used in the manufacture of the emulsion prior to obtaining the oleogel have been evaluated through the analysis of droplet size and rheological properties of obtained emulsions and oleogels. The results show that the emulsion prepared in the high-pressure homogenizer (HPH) at higher pressure values has smaller droplet sizes and a higher uniformity in the size distribution curve. On the other hand, in relation to the rheological characteristics of the emulsions and oleogels obtained, the predominantly elastic character of the systems must be noted, as they present values of the storage modulus higher than those of losses, also showing an important plateau zone, typical of structured systems. In the same way, if steady-state viscous flow tests have been analyzed on both emulsions and oleogels, the result is that, once again, the pressure used in the homogenizer is an important factor for obtaining emulsions with adequate droplet size and the subsequent oleogel. Thus, various routes for trapping oil inside a biopolymer matrix with adjustable mechanical properties could be applied for the creation of the three-dimensional network in order to the oil absorption and creating oleogel.Keywords: basil seed gum, particle size, viscoelastic properties, whey protein
Procedia PDF Downloads 663822 IL-23, an Inflammatory Cytokine, Decreased by Shark Cartilage and Vitamin A Oral Treatment in Patient with Gastric Cancer
Authors: Razieh Zarei, Hassan zm, Abolghasem Ajami, Darush Moslemi, Narges Afsary, Amrollah Mostafa-zade
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Introduction: IL-23 is responsible for the differentiation and expansion of Th17/ThIL-17 cells from naive CD4+ T cells. Therefore, may be IL-23/IL17 axis involve in a variety of allergic and autoimmune diseases, such as RA, MS, inflammatory bowel disease (IBD), and asthma. TGF-β is also share for the differentiation Th17 producing IL-17 and CD4+CD25+Foxp3hiT regulatory cells from naïve CD4+ T cells which are involved in the regulation of immune response, maintaining immunological self-tolerance and immune homeostasis ,and the control of autoimmunity and cancer surveillance. Therefore, T regulatory cells play a key role in autoimmunity, allergy, cancer, infectious disease, and the induction of transplantation tolerance. Vitamin A and it's derivatives (retinoids) inhibit or reverse the carcinogenic process in some types of cancers in oral cavity,head and neck, breast, skin, liver, and blood cells. Shark is a murine organism and its cartilage has antitumor peptides to prevent angiogenesis, in vitro. Our purpose is whether simultaneous oral treatment vitamin A and shark cartilage can modulate IL-23/IL-17 and CD4CD25Foxp3 T regulatory cell/TGF-β pathways and Th1/Th2 immunity in patients with gastric cancer. Materials and Methods: First investigated an imbalanced supernatant of cytokines exist in patients with gastric cancer by ELISA. Associated with cytokines measuring such as IL-23,IL-17,TGF-β,IL-4 and γ-IFN, then flow cytometry was employed to determine whether the peripheral blood mononuclear cells such as CD4+CD25+Foxp3highT regulatory cells in patients with gastric cancer were changed correspondingly. Results: An imbalance between IL-17 secretion and TGF-β/Foxp3 t regulatory cell pathway and so, Th1 immunity (γ-IFN production) and TH2 immunity (IL-4 secretion) was not seen in patients with gastric cancer treated by vitamin A and shark cartilage. But, the simultaneously presented down-regulation of IL-23 indicated, at least cytokine level. Conclusion: Il-23, as a pro-angiogenesis cytokine, probably, help to tumor growth. Hence, suggested that down-regulation of IL-23, at least cytokine level, is useful for anti-tumor immune responses in patients with gastric cancer.Keywords: IL-23/IL17 axis, TGF-β/CD4CD25Foxp3 T regulatory pathway, γ-IFN, IL-4, shark cartilage and gastric cancer
Procedia PDF Downloads 3953821 Medication Side Effects: Implications on the Mental Health and Adherence Behaviour of Patients with Hypertension
Authors: Irene Kretchy, Frances Owusu-Daaku, Samuel Danquah
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Hypertension is the leading risk factor for cardiovascular diseases, and a major cause of death and disability worldwide. This study examined whether psychosocial variables influenced patients’ perception and experience of side effects of their medicines, how they coped with these experiences and the impact on mental health and medication adherence to conventional hypertension therapies. Methods: A hospital-based mixed methods study, using quantitative and qualitative approaches was conducted on hypertensive patients. Participants were asked about side effects, medication adherence, common psychological symptoms, and coping mechanisms with the aid of standard questionnaires. Information from the quantitative phase was analyzed with the Statistical Package for Social Sciences (SPSS) version 20. The interviews from the qualitative study were audio-taped with a digital audio recorder, manually transcribed and analyzed using thematic content analysis. The themes originated from participant interviews a posteriori. Results: The experiences of side effects – such as palpitations, frequent urination, recurrent bouts of hunger, erectile dysfunction, dizziness, cough, physical exhaustion - were categorized as no/low (39.75%), moderate (53.0%) and high (7.25%). Significant relationships between depression (x 2 = 24.21, P < 0.0001), anxiety (x 2 = 42.33, P < 0.0001), stress (x 2 = 39.73, P < 0.0001) and side effects were observed. A logistic regression model using the adjusted results for this association are reported – depression [OR = 1.9 (1.03 – 3.57), p = 0.04], anxiety [OR = 1.5 (1.22 – 1.77), p = < 0.001], and stress [OR = 1.3 (1.02 – 1.71), p = 0.04]. Side effects significantly increased the probability of individuals to be non-adherent [OR = 4.84 (95% CI 1.07 – 1.85), p = 0.04] with social factors, media influences and attitudes of primary caregivers further explaining this relationship. The personal adoption of medication modifying strategies, espousing the use of complementary and alternative treatments, and interventions made by clinicians were the main forms of coping with side effects. Conclusions: Results from this study show that contrary to a biomedical approach, the experience of side effects has biological, social and psychological interrelations. The result offers more support for the need for a multi-disciplinary approach to healthcare where all forms of expertise are incorporated into health provision and patient care. Additionally, medication side effects should be considered as a possible cause of non-adherence among hypertensive patients, thus addressing this problem from a Biopsychosocial perspective in any intervention may improve adherence and invariably control blood pressure.Keywords: biopsychosocial, hypertension, medication adherence, psychological disorders
Procedia PDF Downloads 3713820 From Private Bodies to a Shareable Body Politic. A Theological Solution to a Foundational Political Problem.
Authors: Patrick Downey
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The political problem besetting all nations, tribes, and families, as illuminated by Plato in the fifth book of his Republic, is the problem of our own private body with its own particular pleasures and pains. This problem we might label the “irrational love of one’s own.” The reasonable philosopher loves reality just because it is, but we love things only if we can convince ourselves that they are “ours” or an imaginative extension of “ours.” The resulting problem, that can only be medicated, but not cured, is that the “body private,” whether our own, our family, tribe, or nation, always lies underneath any level of “body politic” and threatens the bloodshed and disintegration of civil war. This is also the political problem the Bible deals with throughout, beginning with Adam and Eve’s fall from rationally shareable bodies (“the two were one flesh”) into unshareable bodies whose now shameful “privacy” must be hid behind a bloody rather than bloodless veil. The blood is the sign of always threatening civil war, whether murder between brothers, feuds within tribes, or later, war between nations. The scarlet thread of blood tying the entire Bible together, Old and New Testament, reminds us that however far our loves are pushed out beyond our private body to family, tribe or nation, they remain irrational because unshareable. Only by loving the creator God who first loved us, can we rationally love anything of our own, but it must be loved as gift rather than as a possession. Such a love renders all bodies and nations truly shareable, and achieving this shareability is the paradoxical plot of the Bible, wherein the Word becomes flesh in a particular body amidst a particular people and nation. Yet even with His own nation and His own Son, this Lord is not “partial” and demands justice towards widows, orphans, and sojourners, because the irrational love of only our own can become rational solely through the resurrection of this particular body, king of this particular nation and these particular people. His body, along with all other bodies, can thus now retain their particular wounds and history, while yet remaining shareable. Likewise, all nations will share in the nation of Israel, in the same way all distinct languages will share an understanding through the inner rational word that we see illustrated in Pentecost. Without the resurrection, however, this shareability of bodies and nations remains merely a useful fiction, as Plato saw, and the equally fictitious “rationality” of some sort of deductive universalism will not go away. Reading Scripture in terms of Plato’s “irrational love of one’s own” therefore raises questions for both a Protestant and Catholic understanding of nations, questions that neither can answer adequately without this philosophical and exegetical attention.Keywords: body private, nations, shareability, body politic
Procedia PDF Downloads 893819 Behavior of GRS Abutment Facing under Variable Cycles of Lateral Excitation through Physical Model Tests
Authors: Ashutosh Verma, Satyendra Mittal
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Numerous geosynthetic reinforced soil (GRS) abutment failures over the years have been attributed to the loss of strength at the facing-reinforcement interface due to seasonal thermal expansion/contraction of the bridge deck. This causes excessive settlement below the bridge seat, causing bridge bumps along the approach road which reduces the design life of any abutment. Before designers while choosing the type of facing, a broad range of facing configurations are undoubtedly available. Generally speaking, these configurations can be divided into three groups: modular (panels/block), continuous, and full height rigid (FHR). The purpose of the current study is to use 1g physical model tests under serviceable cyclic lateral displacements to experimentally investigate the behaviour of these three facing classifications. To simulate field behaviour, a field instrumented GRS abutment prototype was modeled into a N scaled down 1g physical model (N = 5) with adjustable facing arrangements to represent these three facing classifications. For cyclic lateral displacement (d/H) of top facing at loading rate of 1mm/min, the peak earth pressure coefficient (K) on the facing and vertical settlement of the footing (s/B) at 25, 50, 75 and 100 cycles have been measured. For a constant footing offset of x/H = 0.1, three forms of cyclic displacements have been performed to simulate active condition (CA), passive condition (CP), and active-passive condition (CAP). The findings showed that when reinforcements are integrated into the wall along with presence of gravel gabions i.e. FHR design, a rather substantial earth pressure occurs over the facing. Despite this, the FHR facing's continuous nature works in conjunction with the reinforcements' membrane resilience to reduce footing settlement. On the other hand, the pressure over the wall is released upon lateral excitation by the relative displacement between the panels in modular facing reducing the connection strength at the interface and leading to greater settlements below footing. On the contrary, continuous facing do not exhibit relative displacement along the depth of facing rather fails through rotation about the base, which extends the zone of active failure in the backfill leading to large depressions in the backfill region around the bridge seat. Conservatively, FHR facing shows relatively stable responses under lateral cyclic excitations as compared to modular or continuous type of abutment facing.Keywords: GRS abutments, 1g physical model, full height rigid, cyclic lateral displacement
Procedia PDF Downloads 833818 Accelerated Carbonation of Construction Materials by Using Slag from Steel and Metal Production as Substitute for Conventional Raw Materials
Authors: Karen Fuchs, Michael Prokein, Nils Mölders, Manfred Renner, Eckhard Weidner
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Due to the high CO₂ emissions, the energy consumption for the production of sand-lime bricks is of great concern. Especially the production of quicklime from limestone and the energy consumption for hydrothermal curing contribute to high CO₂ emissions. Hydrothermal curing is carried out under a saturated steam atmosphere at about 15 bar and 200°C for 12 hours. Therefore, we are investigating the opportunity to replace quicklime and sand in the production of building materials with different types of slag as calcium-rich waste from steel production. We are also investigating the possibility of substituting conventional hydrothermal curing with CO₂ curing. Six different slags (Linz-Donawitz (LD), ferrochrome (FeCr), ladle (LS), stainless steel (SS), ladle furnace (LF), electric arc furnace (EAF)) provided by "thyssenkrupp MillServices & Systems GmbH" were ground at "Loesche GmbH". Cylindrical blocks with a diameter of 100 mm were pressed at 12 MPa. The composition of the blocks varied between pure slag and mixtures of slag and sand. The effects of pressure, temperature, and time on the CO₂ curing process were studied in a 2-liter high-pressure autoclave. Pressures between 0.1 and 5 MPa, temperatures between 25 and 140°C, and curing times between 1 and 100 hours were considered. The quality of the CO₂-cured blocks was determined by measuring the compressive strength by "Ruhrbaustoffwerke GmbH & Co. KG." The degree of carbonation was determined by total inorganic carbon (TIC) and X-ray diffraction (XRD) measurements. The pH trends in the cross-section of the blocks were monitored using phenolphthalein as a liquid pH indicator. The parameter set that yielded the best performing material was tested on all slag types. In addition, the method was scaled to steel slag-based building blocks (240 mm x 115 mm x 60 mm) provided by "Ruhrbaustoffwerke GmbH & Co. KG" and CO₂-cured in a 20-liter high-pressure autoclave. The results show that CO₂ curing of building blocks consisting of pure wetted LD slag leads to severe cracking of the cylindrical specimens. The high CO₂ uptake leads to an expansion of the specimens. However, if LD slag is used only proportionally to replace quicklime completely and sand proportionally, dimensionally stable bricks with high compressive strength are produced. The tests to determine the optimum pressure and temperature show 2 MPa and 50°C as promising parameters for the CO₂ curing process. At these parameters and after 3 h, the compressive strength of LD slag blocks reaches the highest average value of almost 50 N/mm². This is more than double that of conventional sand-lime bricks. Longer CO₂ curing times do not result in higher compressive strengths. XRD and TIC measurements confirmed the formation of carbonates. All tested slag-based bricks show higher compressive strengths compared to conventional sand-lime bricks. However, the type of slag has a significant influence on the compressive strength values. The results of the tests in the 20-liter plant agreed well with the results of the 2-liter tests. With its comparatively moderate operating conditions, the CO₂ curing process has a high potential for saving CO₂ emissions.Keywords: CO₂ curing, carbonation, CCU, steel slag
Procedia PDF Downloads 1043817 Effects of Organic Chromium and Propylene Glycol on Milk Yield and Some Serum Biochemical Parameters of Early Lactation Dairy Cows
Authors: Cangir Uyarlar, Ismail Bayram, Ibrahim Sadi Cetingul, Mustafa Kabu, Eyup Eren Gultepe
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This study was conducted to determine the effects of organic chromium and organic chromium+propylene glycol on milk yield and some blood parameters related with liver fatty acid metabolism in early lactation dairy cows. Thirty multiparous Holstein dairy cows were used as study material. Cows assigned to three groups as control (C), chromium (Cr) and chromium+propylene glycol (CP). Live weight, parity and body condition score were used as covariates for statistical analyses. The study began at calving and finished at 3 weeks after calving. All cows were consumed same diet. Organic chromium and organic chromium+propylene glycol were orally administrated to cows in treatment groups shortly after the morning milking. Blood samples were collected from all cows on 0 (calving), 3rd, 6th, 9th, 12th, 15th, 18th, 21th days after calving. Then, samples were analyzed for BHBA (Betahydroxybutiric acids), NEFA (Non Esterified Fatty Acids), urea, total protein (TP) and glucose concentrations. Weekly milk yields were calculated from daily milk data on farm. Organic chromium treatment had no significant differences on serum biochemical parameters and milk yields. However, administration of organic chromium and propylene glycol combination decreased serum urea and total protein concentration, helped to protection from subclinical metabolic diseases via decreasing serum NEFA and BHBA concentrations. Also, this combination decreased serum glucose levels of cows. Neither only chromium nor chromium and propylene glycol combination did not affect milk yield throughout the study. These findings were suggested that orally administrations of chromium and propylene glycol combination improved liver glucose and fatty acid metabolism, decreased serum parameters which are representing subclinical diseases in early lactation dairy cows.Keywords: chromium, early lactation dairy cows, propylene glycol, milk yield
Procedia PDF Downloads 4923816 Revealing the Sustainable Development Mechanism of Guilin Tourism Based on Driving Force/Pressure/State/Impact/Response Framework
Authors: Xiujing Chen, Thammananya Sakcharoen, Wilailuk Niyommaneerat
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China's tourism industry is in a state of shock and recovery, although COVID-19 has brought great impact and challenges to the tourism industry. The theory of sustainable development originates from the contradiction of increasing awareness of environmental protection and the pursuit of economic interests. The sustainable development of tourism should consider social, economic, and environmental factors and develop tourism in a planned and targeted way from the overall situation. Guilin is one of the popular tourist cities in China. However, there exist several problems in Guilin tourism, such as low quality of scenic spot construction and low efficiency of tourism resource development. Due to its unwell-managed, Guilin's tourism industry is facing problems such as supply and demand crowding pressure for tourists. According to the data from 2009 to 2019, there is a change in the degree of sustainable development of Guilin tourism. This research aimed to evaluate the sustainable development state of Guilin tourism using the DPSIR (driving force/pressure/state/impact/response) framework and to provide suggestions and recommendations for sustainable development in Guilin. An improved TOPSIS (technology for order preference by similarity to an ideal solution) model based on the entropy weights relationship is applied to the quantitative analysis and to analyze the mechanisms of sustainable development of tourism in Guilin. The DPSIR framework organizes indicators into sub-five categories: of which twenty-eight indicators related to sustainable aspects of Guilin tourism are classified. The study analyzed and summarized the economic, social, and ecological effects generated by tourism development in Guilin from 2009-2019. The results show that the conversion rate of tourism development in Guilin into regional economic benefits is more efficient than that into social benefits. Thus, tourism development is an important driving force of Guilin's economic growth. In addition, the study also analyzed the static weights of 28 relevant indicators of sustainable development of tourism in Guilin and ranked them from largest to smallest. Then it was found that the economic and social factors related to tourism revenue occupy the highest weight, which means that the economic and social development of Guilin can influence the sustainable development of Guilin tourism to a greater extent. Therefore, there is a two-way causal relationship between tourism development and economic growth in Guilin. At the same time, ecological development-related indicators also have relatively large weights, so ecological and environmental resources also have a great influence on the sustainable development of Guilin tourism.Keywords: DPSIR framework, entropy weights analysis, sustainable development of tourism, TOPSIS analysis
Procedia PDF Downloads 983815 Model Evaluation of Action Potential Block in Whole-Animal Nerves Induced by Ultrashort, High-Intensity Electric Pulses
Authors: Jiahui Song
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There have been decades of research into the action potential block in nerves. To our best knowledge electrical voltages can reversibly block the conduction of action potentials across whole animal nerves. Blocking biological electrical signaling pathways can have a variety of applications in muscular and sensory incapacitation and clinical research, including urethral pressure reduction and relieving chronic pain relief from a peripheral nerve injury. The cessation ability has been used in muscle activation and fatigue reduction. Ultrashort, high-intensity electric pulses modulate the membrane conductivity to block nerve conduction through the electroporation process. Nanopore formation on the membrane surface would increase the local membrane conductivity and effectively "short-out" the trans-membrane potential of a nerve that inhibits action potential propagation. This block would be similar in concept to stopping the propagation of an air-pressure wave down a "leaky" pipe. This research focuses on a distributed electrical model with an additional time-dependent membrane conductance to calculate the poration induced by the ultrashort, high-intensity electric pulses. The changes in membrane conductivity are used to predict changes in action potential transmission. A "strength-duration (SD)" curve is generated for action potential blockage and would be used as a design guide for benchmarking safety thresholds or setting the pulse voltage and/or durations necessary for neuro-muscular incapacitation.Keywords: action potential, ultrashort, high-intensity, nerve, strength-duration
Procedia PDF Downloads 183814 Improving Depression, Anxiety and Distress Symptoms in Type 2 Diabetes Patients
Authors: Seyed Reza Alvani, Norzarina Mohd Zaharim
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Diabetes mellitus is one of the chronic, progressive illnesses that has reached a widespread level all over the world and considered an extreme life-threatening condition in South East Asian countries region include Malaysia. Co-morbid psychological factors like diabetes-related distress and low level of psychological well-being are related to high levels of blood sugar and hypo/hyperglycemia complications. As a result, the implementation of any effective psychological interventions among diabetes patients is necessary. One such intervention is cognitive behavioural therapy (CBT) that is approved and suggested by many professionals as an empirically-supported technique of treatment for people how are suffering from diabetes around the world where there is no clear evidence of using this technique in Malaysia. The target of this study was to see whether or not participation in group CBT would end in an improvement of psychological well-being (by decreasing the levels of depression and anxiety) and diabetes-related distress followed by lower level of blood sugar level. The sample of the present study was 60 type 2 diabetes adults (ages 20-65) with HbA1c ≥ 7 from Universiti Sains Malaysia (USM) clinic. All participants were selected by the convenience sampling technique. Participants completed Well-Being Questionaire (W-BQ) and Distress Scale (DDS-17) after signing written consent form. Those participants who were interested to join CBT groups were placed to the experimental groups, and people who were not interested were assigned to the control group. The experimental groups (n = 30) received group CBT, whereas participants in the control group (n = 30) did not receive any kind of psychological intervention. For testing the effect of intervention, mixed between-within ANOVA used. The entire intervention program took three months, and a significant improvement in the level of psychological well-being and decline in the level of diabetes distress observed among participants from experimental group, but not for those in the control group. Additionally, the result of the study suggested that group CBT could help participants in experimental group achieve more acceptable HbA1c levels in comparison with those in the control group. Malaysian Ministry of Health, researcher and governors should give due interest and commitment to psychological care as a pathway to diabetes mitigation among Malaysian adults.Keywords: cognitive behavioral therapy, diabetes related distress, diabetes type 2, Malaysia, well-being
Procedia PDF Downloads 1313813 Experimental Study on Performance of a Planar Membrane Humidifier for a Proton Exchange Membrane Fuel Cell Stack
Authors: Chen-Yu Chen, Wei-Mon Yan, Chi-Nan Lai, Jian-Hao Su
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The proton exchange membrane fuel cell (PEMFC) becomes more important as an alternative energy source recently. Maintaining proper water content in the membrane is one of the key requirements for optimizing the PEMFC performance. The planar membrane humidifier has the advantages of simple structure, low cost, low-pressure drop, light weight, reliable performance and good gas separability. Thus, it is a common external humidifier for PEMFCs. In this work, a planar membrane humidifier for kW-scale PEMFCs is developed successfully. The heat and mass transfer of humidifier is discussed, and its performance is analyzed in term of dew point approach temperature (DPAT), water vapor transfer rate (WVTR) and water recovery ratio (WRR). The DPAT of the humidifier with the counter flow approach reaches about 6°C under inlet dry air of 50°C and 60% RH and inlet humid air of 70°C and 100% RH. The rate of pressure loss of the humidifier is 5.0×10² Pa/min at the torque of 7 N-m, which reaches the standard of commercial planar membrane humidifiers. From the tests, it is found that increasing the air flow rate increases the WVTR. However, the DPAT and the WRR are not improved by increasing the WVTR as the air flow rate is higher than the optimal value. In addition, increasing the inlet temperature or the humidity of dry air decreases the WVTR and the WRR. Nevertheless, the DPAT is improved at elevated inlet temperatures or humidities of dry air. Furthermore, the performance of the humidifier with the counter flow approach is better than that with the parallel flow approach. The DPAT difference between the two flow approaches reaches up to 8 °C.Keywords: heat and mass transfer, humidifier performance, PEM fuel cell, planar membrane humidifier
Procedia PDF Downloads 3073812 qPCR Method for Detection of Halal Food Adulteration
Authors: Gabriela Borilova, Monika Petrakova, Petr Kralik
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Nowadays, European producers are increasingly interested in the production of halal meat products. Halal meat has been increasingly appearing in the EU's market network and meat products from European producers are being exported to Islamic countries. Halal criteria are mainly related to the origin of muscle used in production, and also to the way products are obtained and processed. Although the EU has legislatively addressed the question of food authenticity, the circumstances of previous years when products with undeclared horse or poultry meat content appeared on EU markets raised the question of the effectiveness of control mechanisms. Replacement of expensive or not-available types of meat for low-priced meat has been on a global scale for a long time. Likewise, halal products may be contaminated (falsified) by pork or food components obtained from pigs. These components include collagen, offal, pork fat, mechanically separated pork, emulsifier, blood, dried blood, dried blood plasma, gelatin, and others. These substances can influence sensory properties of the meat products - color, aroma, flavor, consistency and texture or they are added for preservation and stabilization. Food manufacturers sometimes access these substances mainly due to their dense availability and low prices. However, the use of these substances is not always declared on the product packaging. Verification of the presence of declared ingredients, including the detection of undeclared ingredients, are among the basic control procedures for determining the authenticity of food. Molecular biology methods, based on DNA analysis, offer rapid and sensitive testing. The PCR method and its modification can be successfully used to identify animal species in single- and multi-ingredient raw and processed foods and qPCR is the first choice for food analysis. Like all PCR-based methods, it is simple to implement and its greatest advantage is the absence of post-PCR visualization by electrophoresis. qPCR allows detection of trace amounts of nucleic acids, and by comparing an unknown sample with a calibration curve, it can also provide information on the absolute quantity of individual components in the sample. Our study addresses a problem that is related to the fact that the molecular biological approach of most of the work associated with the identification and quantification of animal species is based on the construction of specific primers amplifying the selected section of the mitochondrial genome. In addition, the sections amplified in conventional PCR are relatively long (hundreds of bp) and unsuitable for use in qPCR, because in DNA fragmentation, amplification of long target sequences is quite limited. Our study focuses on finding a suitable genomic DNA target and optimizing qPCR to reduce variability and distortion of results, which is necessary for the correct interpretation of quantification results. In halal products, the impact of falsification of meat products by the addition of components derived from pigs is all the greater that it is not just about the economic aspect but above all about the religious and social aspect. This work was supported by the Ministry of Agriculture of the Czech Republic (QJ1530107).Keywords: food fraud, halal food, pork, qPCR
Procedia PDF Downloads 2473811 Chronic Aflatoxin Exposure During Pregnancy Is Associated With Lower Fetal Growth Trajectories: A Prospective Cohort Study in Rural Ethiopia
Authors: K. Tesfamariam, S. Gebreyesus, C. Lachat, P. Kolsteren, S. De Saeger, M. De Boevre, A. Argaw
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Aflatoxins are toxic secondary metabolites produced by Aspergillus fungi, which are ubiquitously present in the food supplies of low- and middle-income countries. Studies of maternal aflatoxin exposure and fetal outcomes are mainly focused on size at birth and the effect on intrauterine fetal growth has not been assessed using repeated longitudinal fetal biometry across gestation. Therefore, this study intends to assess the association between chronic aflatoxin exposure during pregnancy and fetal growth trajectories in a rural Ethiopian setting. In a prospective cohort study, we enrolled 492 pregnant women. A phlebotomist collected 5 mL of a venous blood sample from eligible women before 28 completed weeks of gestation and aflatoxin B1-lysine concentration was determined using liquid chromatography-tandem mass spectrometry. The mean (±SD) gestational age was 19.1 (3.71) weeks at enrollment, and 28.5 (3.51) and 34.5 (2.44) weeks of gestation at the second and third rounds of ultrasound measurements, respectively. Estimated fetal weight was expressed in centiles using the INTERGROWTH-21st reference. We fitted a multivariable linear mixed-effects model to estimate the rate of fetal growth between aflatoxin-exposed (i.e., aflatoxin B1-lysine concentration above or equal to the limit of detection) and non-exposed mothers in the study. Mothers had a mean (±SD) age of 26.0 (4.58) years. The median (P25, P75) serum AFB1-lysine concentration was 12.6 (0.93, 96.9) pg/mg albumin, and aflatoxin exposure was observed in 86.6% of maternal blood samples. Eighty-five percent of the women enrolled provided at least two ultrasound measurements for analysis. On average, the aflatoxin-exposed group had a significantly lower change over time in fetal weight-for-gestational age centile than the unexposed group (ß = -1.01 centiles/week, 95% CI: -1.87, -0.15, p = 0.02). Chronic maternal AF exposure is associated with lower fetal weight gain over time. Our findings emphasize the importance of nutrition-sensitive strategies to mitigate dietary aflatoxin exposure as well as adopting food safety measures in low-income settings, particularly during the fetal period of development.Keywords: aflatoxin, fetal growth, low-income setting, mycotoxins
Procedia PDF Downloads 1423810 Relocating Migration for Higher Education: Analytical Account of Students' Perspective
Authors: Sumit Kumar
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The present study aims to identify the factors responsible for the internal migration of students other than push & pull factors; associated with the source region and destination region, respectively, as classified in classical geography. But in this classification of factors responsible for the migration of students, an agency of individual and the family he/she belongs to, have not been recognized which has later become the centre of the argument for describing and analyzing migration in New Economic theory of migration and New Economics of labour migration respectively. In this backdrop, the present study aims to understand the agency of an individual and the family members regarding one’s migration for higher education. Therefore, this study draws upon New Economic theory of migration and New Economics of labour migration for identifying the agency of individual or family in the context of migration. Further, migration for higher education consists not only the decision to migrate but also where to migrate (location), which university, which college and which course to pursue, also. In order to understand the role of various individuals at various stage of student migration, present study seeks help from the social networking approach for migration which identifies the individuals who facilitate the process of migration by reducing negative externalities of migration through sharing information and various other sorts of help to the migrant. Furthermore, this study also aims to rank those individuals who have helped migrants at various stages of migration for higher education in taking a decision, along with the factors responsible for their migration on the basis of their perception. In order to fulfill the above mentioned objectives of this study, quantification of qualitative data (perception of respondents) has been done employing through frequency distribution analysis. Qualitative data has been collected at two levels but questionnaire survey was the tool for data collection at both the occasions. Twenty five students who have migrated to other state for the purpose of higher education have been approached for pre-questionnaire survey consisting open-ended questions while one hundred students belonging to the same clientele have been approached for questionnaire survey consisting close-ended questions. This study has identified social pressure, peer group pressure and parental pressure; variables not constituting push & pull factors, very important for students’ migration. They have been even assigned better ranked by the respondents than push factors. Further, self (migrant themselves) have been ranked followed by parents by the respondents when it comes to take various decisions attached with the process of migration. Therefore, it can be said without sounding cynical that there are other factors other than push & pull factors which do facilitate the process of migration for higher education not only at the level to migrate but also at other levels intrinsic to the process of migration for higher education.Keywords: agency, migration for higher education, perception, push and pull factors
Procedia PDF Downloads 2443809 Post-Exercise Recovery Tracking Based on Electrocardiography-Derived Features
Authors: Pavel Bulai, Taras Pitlik, Tatsiana Kulahava, Timofei Lipski
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The method of Electrocardiography (ECG) interpretation for post-exercise recovery tracking was developed. Metabolic indices (aerobic and anaerobic) were designed using ECG-derived features. This study reports the associations between aerobic and anaerobic indices and classical parameters of the person’s physiological state, including blood biochemistry, glycogen concentration and VO2max changes. During the study 9 participants, healthy, physically active medium trained men and women, which trained 2-4 times per week for at least 9 weeks, fulfilled (i) ECG monitoring using Apple Watch Series 4 (AWS4); (ii) blood biochemical analysis; (iii) maximal oxygen consumption (VO2max) test, (iv) bioimpedance analysis (BIA). ECG signals from a single-lead wrist-wearable device were processed with detection of QRS-complex. Aerobic index (AI) was derived as the normalized slope of QR segment. Anaerobic index (ANI) was derived as the normalized slope of SJ segment. Biochemical parameters, glycogen content and VO2max were evaluated eight times within 3-60 hours after training. ECGs were recorded 5 times per day, plus before and after training, cycloergometry and BIA. The negative correlation between AI and blood markers of the muscles functional status including creatine phosphokinase (r=-0.238, p < 0.008), aspartate aminotransferase (r=-0.249, p < 0.004) and uric acid (r = -0.293, p<0.004) were observed. ANI was also correlated with creatine phosphokinase (r= -0.265, p < 0.003), aspartate aminotransferase (r = -0.292, p < 0.001), lactate dehydrogenase (LDH) (r = -0.190, p < 0.050). So, when the level of muscular enzymes increases during post-exercise fatigue, AI and ANI decrease. During recovery, the level of metabolites is restored, and metabolic indices rising is registered. It can be concluded that AI and ANI adequately reflect the physiology of the muscles during recovery. One of the markers of an athlete’s physiological state is the ratio between testosterone and cortisol (TCR). TCR provides a relative indication of anabolic-catabolic balance and is considered to be more sensitive to training stress than measuring testosterone and cortisol separately. AI shows a strong negative correlation with TCR (r=-0.437, p < 0.001) and correctly represents post-exercise physiology. In order to reveal the relation between the ECG-derived metabolic indices and the state of the cardiorespiratory system, direct measurements of VO2max were carried out at various time points after training sessions. The negative correlation between AI and VO2max (r = -0.342, p < 0.001) was obtained. These data testifying VO2max rising during fatigue are controversial. However, some studies have revealed increased stroke volume after training, that agrees with findings. It is important to note that post-exercise increase in VO2max does not mean an athlete’s readiness for the next training session, because the recovery of the cardiovascular system occurs over a substantially longer period. Negative correlations registered for ANI with glycogen (r = -0.303, p < 0.001), albumin (r = -0.205, p < 0.021) and creatinine (r = -0.268, p < 0.002) reflect the dehydration status of participants after training. Correlations between designed metabolic indices and physiological parameters revealed in this study can be considered as the sufficient evidence to use these indices for assessing the state of person’s aerobic and anaerobic metabolic systems after training during fatigue, recovery and supercompensation.Keywords: aerobic index, anaerobic index, electrocardiography, supercompensation
Procedia PDF Downloads 1153808 Assessment of the Effect of Orally Administered Itopride on Gall Bladder Ejection Fraction by a Fatty Meal Cholescintigraphy in Patients with Diabetes
Authors: Avani Jain, Hasmukh Jain, S. Shelley, M. Indirani, Shilpa Kalal, Jayakanth Amalachandran
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Aim of the Study: To assess the effect of orally administered Itopride on gall bladder ejection fraction by fatty meal cholescintigraphy in patients with diabetes. Materials and Methods: Thirty patients (20 males, 10 females, mean age 46+10 yrs) with history of diabetes mellitus (mean duration 4.8+4.1 yrs, fasting blood glucose level 130+35 mg/dl and 2-hours post-prandial blood glucose level 196+76 mg/dl) and found to have gall bladder dysfunction on fatty-meal stimulated cholescintigraphy were selected for this study. These patients underwent a repeat cholescintigraphy similar to baseline study, with 50 mg of Itopride orally along with fatty meal. Pre- and post-Itopride GBEF were then compared to assess the effect of Itopride on gall bladder contraction. Results: Out of these 30 patients, 2 had dyskinetic, 4 had akinetic, 22 had moderately hypokinetic and the remaining 2 had hypokinetic gall bladder function in the baseline study with > 60% GBEF being taken as the normal value. Mean percentage of GBEF in the baseline study was 32%+13% and the mean percentage of GBEF in the post-Itopride study was 57%+17% with change in mean percentage of GBEF being 24%+21%. GBEF of the “baseline study” was significantly lower as compared to GBEF in the “post-Itopride study” (p < 0.05). Conclusion: Diabetic patients with biliary-type pain often tend to have impaired gallbladder function. Cholescintigraphy with fatty meal-stimulation is a simple, cheap and useful investigation for assessment of gallbladder dysfunction in these patients, before any structural changes occur within the lumen or wall of the gall bladder. Improvement in gallbladder ejection fraction after oral administration of a single dose of Itopride, a newer prokinetic drug with fewer side effects, as assessed by cholescintigraphy, provides enough evidence of future therapeutic response. Administration of Itopride, in therapeutic dosage, therefore may be expected to cause significant improvement in gallbladder ejection fraction and hence prolong stone formation within the gall bladder and also prevent the associated long term complications. Hence, based on scintigraphic evidence, Itopride may be recommended, by clinicians, for management of symptomatic diabetic patients having gallbladder dysfunction.Keywords: itopride, gall bladder ejection fraction, fatty meal, cholescintigraphy, diabetes
Procedia PDF Downloads 4253807 Numerical Simulation of the Dynamic Behavior of a LaNi5 Water Pumping System
Authors: Miled Amel, Ben Maad Hatem, Askri Faouzi, Ben Nasrallah Sassi
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Metal hydride water pumping system uses hydrogen as working fluid to pump water for low head and high discharge. The principal operation of this pump is based on the desorption of hydrogen at high pressure and its absorption at low pressure by a metal hydride. This work is devoted to study a concept of the dynamic behavior of a metal hydride pump using unsteady model and LaNi5 as hydriding alloy. This study shows that with MHP, it is possible to pump 340l/kg-cycle of water in 15 000s using 1 Kg of LaNi5 at a desorption temperature of 360 K, a pumping head equal to 5 m and a desorption gear ratio equal to 33. This study reveals also that the error given by the steady model, using LaNi5 is about 2%.A dimensional mathematical model and the governing equations of the pump were presented to predict the coupled heat and mass transfer within the MHP. Then, a numerical simulation is carried out to present the time evolution of the specific water discharge and to test the effect of different parameters (desorption temperature, absorption temperature, desorption gear ratio) on the performance of the water pumping system (specific water discharge, pumping efficiency and pumping time). In addition, a comparison between results obtained with steady and unsteady model is performed with different hydride mass. Finally, a geometric configuration of the reactor is simulated to optimize the pumping time.Keywords: dynamic behavior, LaNi5, performance of water pumping system, unsteady model
Procedia PDF Downloads 2053806 A Transient Coupled Numerical Analysis of the Flow of Magnetorheological Fluids in Closed Domains
Authors: Wael Elsaady, S. Olutunde Oyadiji, Adel Nasser
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The non-linear flow characteristics of magnetorheological (MR) fluids in MR dampers are studied via a coupled numerical approach that incorporates a two-phase flow model. The approach couples the Finite Element (FE) modelling of the damper magnetic circuit, with the Computational Fluid Dynamics (CFD) analysis of the flow field in the damper. The two-phase flow CFD model accounts for the effect of fluid compressibility due to the presence of liquid and gas in the closed domain of the damper. The dynamic mesh model included in ANSYS/Fluent CFD solver is used to simulate the movement of the MR damper piston in order to perform the fluid excitation. The two-phase flow analysis is studied by both Volume-Of-Fluid (VOF) model and mixture model that are included in ANSYS/Fluent. The CFD models show that the hysteretic behaviour of MR dampers is due to the effect of fluid compressibility. The flow field shows the distributions of pressure, velocity, and viscosity contours. In particular, it shows the high non-Newtonian viscosity in the affected fluid regions by the magnetic field and the low Newtonian viscosity elsewhere. Moreover, the dependence of gas volume fraction on the liquid pressure inside the damper is predicted by the mixture model. The presented approach targets a better understanding of the complicated flow characteristics of viscoplastic fluids that could be applied in different applications.Keywords: viscoplastic fluid, magnetic FE analysis, computational fluid dynamics, two-phase flow, dynamic mesh, user-defined functions
Procedia PDF Downloads 1743805 Effects of Exercise in the Cold on Glycolipid Metabolism and Insulin Sensitivity in Obese Rats
Authors: Chaoge Wang, Xiquan Weng, Yan Meng, Wentao Lin
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Objective: Cold exposure and exercise serve as two physiological stimuli to glycolipid metabolism and insulin sensitivity. So far, it remains to be elucidated whether exercise plus cold exposure can produce an addictive effect on promoting glycolipid metabolism and insulin sensitivity. Methods: 64 SD rats were subjected to high-fat and high-sugar diets for 9-week and sucessfully to establish an obesity model. They were randomly divided into 8 groups: normal control group (NC), normal exercise group (NE), continuous cold control group (CC), continuous cold exercise group (CE), acute clod control group (AC), acute cold exercise group (AE), intermittent cold control group (IC) and intermittent cold exercise group (IE). For continuous cold exposure, the rats stayed in a cold environment all day; for acute cold exposure, the rats were exposed to cold for only 4h before the end of the experiment; for intermittent cold exposure, the rats were exposed to cold for 4h per day. The protocol for treadmill runnings were as follows: 25m/min (speed), 0°C (slope), 30 mins each time, an interval for 10 mins between two runnings, twice/two days, lasting for 5 weeks. Sampling were conducted on the 5th weekend. Blood lipids, free fatty acids, blood glucose (FBG), and serum insulin (FINS) were examined, and the insulin resistance index (HOMA-IR = FBG (mmol/L)×FINS(mIU/L)/22.5) was calculated. SPSS 22.0 was used for statistical analysis of the experimental results, and the ANOVA analysis was performed between groups (p < 0.05 was significant). Results: (1) Compared with the NC group, the FBG of the rats was significantly declined in the NE, CE, AC, AE, and IE groups (p < 0.05), the FINS of the rats was significantly declined in the AE group (p < 0.05), the HOMA-IR of the rats was significantly declined in the NE, CE, AC, AE and IE groups (p < 0.05). Compared with the NE group, the FBG of the rats was significantly declined in the CE, AE, and IE groups (p < 0.05), the FINS and HOMA-IR of the rats were significantly declined in the AE group (p < 0.05). (2) Compared with the NC group, the CHO, TG, LDL-C, and FFA of the rats were significantly declined in CE and IE groups (p < 0.05), the HDL-C of the rats was significantly higher in NE, CC, CE, AE, and IE groups (p < 0.05). Compared with the NE group, the HDL-C of the rats was significantly higher in the CE and IE groups (p < 0.05). Conclusions: Sedentariness or exercise in the acute cold doesn't make sense in the treatment of type 2 diabetes, which led to one-off increases of the body's insulin sensitivity. Exercise in the continuous and intermittent cold can effectively decline the FBG, TC, TG, LDL-C, and FFA levels and increase the HDL-C level and insulin sensitivity in obese rats. These results can impact the prevention and treatment of type 2 diabetes.Keywords: cold, exercise, insulin sensitivity, obesity
Procedia PDF Downloads 1443804 Optimization Based Design of Decelerating Duct for Pumpjets
Authors: Mustafa Sengul, Enes Sahin, Sertac Arslan
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Pumpjets are one of the marine propulsion systems frequently used in underwater vehicles nowadays. The reasons for frequent use of pumpjet as a propulsion system are that it has higher relative efficiency at high speeds, better cavitation, and acoustic performance than its rivals. Pumpjets are composed of rotor, stator, and duct, and there are two different types of pumpjet configurations depending on the desired hydrodynamic characteristic, which are with accelerating and decelerating duct. Pumpjet with an accelerating channel is used at cargo ships where it works at low speeds and high loading conditions. The working principle of this type of pumpjet is to maximize the thrust by reducing the pressure of the fluid through the channel and throwing the fluid out from the channel with high momentum. On the other hand, for decelerating ducted pumpjets, the main consideration is to prevent the occurrence of the cavitation phenomenon by increasing the pressure of the fluid about the rotor region. By postponing the cavitation, acoustic noise naturally falls down, so decelerating ducted systems are used at noise-sensitive vehicle systems where acoustic performance is vital. Therefore, duct design becomes a crucial step during pumpjet design. This study, it is aimed to optimize the duct geometry of a decelerating ducted pumpjet for a highly speed underwater vehicle by using proper optimization tools. The target output of this optimization process is to obtain a duct design that maximizes fluid pressure around the rotor region to prevent from cavitation and minimizes drag force. There are two main optimization techniques that could be utilized for this process which are parameter-based optimization and gradient-based optimization. While parameter-based algorithm offers more major changes in interested geometry, which makes user to get close desired geometry, gradient-based algorithm deals with minor local changes in geometry. In parameter-based optimization, the geometry should be parameterized first. Then, by defining upper and lower limits for these parameters, design space is created. Finally, by proper optimization code and analysis, optimum geometry is obtained from this design space. For this duct optimization study, a commercial codedparameter-based optimization algorithm is used. To parameterize the geometry, duct is represented with b-spline curves and control points. These control points have x and y coordinates limits. By regarding these limits, design space is generated.Keywords: pumpjet, decelerating duct design, optimization, underwater vehicles, cavitation, drag minimization
Procedia PDF Downloads 2093803 Sickle Cell Disease: Review of Managements in Pregnancy and the Outcome in Ampang Hospital, Selangor
Authors: Z. Nurzaireena, K. Azalea, T. Azirawaty, S. Jameela, G. Muralitharan
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The aim of this study is the review of the management practices of sickle cell disease patients during pregnancy, as well as the maternal and neonatal outcome at Ampang Hospital, Selangor. The study consisted of a review of pregnant patients with sickle cell disease under follow up at the Hematology Clinic, Ampang Hospital over the last seven years to assess their management and maternal-fetal outcome. The results of the review show that Ampang Hospital is considered the public hematology centre for sickle cell disease and had successfully managed three pregnancies throughout the last seven years. Patients’ presentations, managements and maternal-fetal outcome were compared and reviewed for academic improvements. All three patients were seen very early in their pregnancy and had been given a regime of folic acid, antibiotics and thrombo-prophylactic drugs. Close monitoring of maternal and fetal well being was done by the hematologists and obstetricians. Among the patients, there were multiple admissions during the pregnancy for either a painful sickle cell bone crisis, haemolysis following an infection and anemia requiring phenotype- matched blood and exchange transfusions. Broad spectrum antibiotics coverage during and infection, hydration, pain management and venous-thrombolism prophylaxis were mandatory. The pregnancies managed to reach near term in the third trimester but all required emergency caesarean section for obstetric indications. All pregnancies resulted in live births with good fetal outcome. During post partum all were nursed closely in the high dependency units for further complications and were discharged well. Post partum follow up and contraception counseling was comprehensively given for future pregnancies. Sickle cell disease is uncommonly seen in the East, especially in the South East Asian region, yet more cases are seen in the current decade due to improved medical expertise and advance medical laboratory technologies. Pregnancy itself is a risk factor for sickle cell patients as increased thrombosis event and risk of infections can lead to multiple crisis, haemolysis, anemia and vaso-occlusive complications including eclampsia, cerebrovasular accidents and acute bone pain. Patients mostly require multiple blood product transfusions thus phenotype-matched blood is required to reduce the risk of alloimmunozation. Emphasizing the risks and complications in preconception counseling and establishing an ultimate pregnancy plan would probably reduce the risk of morbidity and mortality to the mother and unborn child. Early management for risk of infection, thromboembolic events and adequate hydration is mandatory. A holistic approach involving multidisciplinary team care between the hematologist, obstetricians, anesthetist, neonatologist and close nursing care for both mother and baby would ensure the best outcome. In conclusion, sickle cell disease by itself is a high risk medical condition and pregnancy would further amplify the risk. Thus, close monitoring with combine multidisciplinary care, counseling and educating the patients are crucial in achieving the safe outcome.Keywords: anaemia, haemoglobinopathies, pregnancy, sickle cell disease
Procedia PDF Downloads 2583802 Simulation of Cure Kinetics and Process-Induced Stresses in Carbon Fibre Composite Laminate Manufactured by a Liquid Composite Molding Technique
Authors: Jayaraman Muniyappan, Bachchan Kr Mishra, Gautam Salkar, Swetha Manian Sridhar
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Vacuum Assisted Resin Transfer Molding (VARTM), a cost effective method of Liquid Composite Molding (LCM), is a single step process where the resin, at atmospheric pressure, is infused through a preform that is maintained under vacuum. This hydrodynamic pressure gradient is responsible for the flow of resin through the dry fabric preform. The current study has a slight variation to traditional VARTM, wherein, the resin infuses through the fabric placed on a heated mold to reduce its viscosity. The saturated preform is subjected to a cure cycle where the resin hardens as it undergoes curing. During this cycle, an uneven temperature distribution through the thickness of the composite and excess exothermic heat released due to different cure rates result in non-uniform curing. Additionally, there is a difference in thermal expansion coefficient between fiber and resin in a given plane and between adjacent plies. All these effects coupled with orthotropic coefficient of thermal expansion of the composite give rise to process-induced stresses in the laminate. Such stresses lead to part deformation when the laminate tries to relieve them as the part is released off the mold. The current study looks at simulating resin infusion, cure kinetics and the structural response of composite laminate subject to process-induced stresses.Keywords: cure kinetics, process-induced stresses, thermal expansion coefficient, vacuum assisted resin transfer molding
Procedia PDF Downloads 2403801 Effect of Three Drying Methods on Antioxidant Efficiency and Vitamin C Content of Moringa oleifera Leaf Extract
Authors: Kenia Martínez, Geniel Talavera, Juan Alonso
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Moringa oleifera is a plant containing many nutrients that are mostly concentrated within the leaves. Commonly, the separation process of these nutrients involves solid-liquid extraction followed by evaporation and drying to obtain a concentrated extract, which is rich in proteins, vitamins, carbohydrates, and other essential nutrients that can be used in the food industry. In this work, three drying methods were used, which involved very different temperature and pressure conditions, to evaluate the effect of each method on the vitamin C content and the antioxidant efficiency of the extracts. Solid-liquid extractions of Moringa leaf (LE) were carried out by employing an ethanol solution (35% v/v) at 50 °C for 2 hours. The resulting extracts were then dried i) in a convective oven (CO) at 100 °C and at an atmospheric pressure of 750 mbar for 8 hours, ii) in a vacuum evaporator (VE) at 50 °C and at 300 mbar for 2 hours, and iii) in a freeze-drier (FD) at -40 °C and at 0.050 mbar for 36 hours. The antioxidant capacity (EC50, mg solids/g DPPH) of the dry solids was calculated by the free radical inhibition method employing DPPH˙ at 517 nm, resulting in a value of 2902.5 ± 14.8 for LE, 3433.1 ± 85.2 for FD, 3980.1 ± 37.2 for VE, and 8123.5 ± 263.3 for CO. The calculated antioxidant efficiency (AE, g DPPH/(mg solids·min)) was 2.920 × 10-5 for LE, 2.884 × 10-5 for FD, 2.512 × 10-5 for VE, and 1.009 × 10-5 for CO. Further, the content of vitamin C (mg/L) determined by HPLC was 59.0 ± 0.3 for LE, 49.7 ± 0.6 for FD, 45.0 ± 0.4 for VE, and 23.6 ± 0.7 for CO. The results indicate that the convective drying preserves vitamin C and antioxidant efficiency to 40% and 34% of the initial value, respectively, while vacuum drying to 76% and 86%, and freeze-drying to 84% and 98%, respectively.Keywords: antioxidant efficiency, convective drying, freeze-drying, Moringa oleifera, vacuum drying, vitamin C content
Procedia PDF Downloads 2693800 Impact of External Temperature on the Speleothem Growth in the Moravian Karst
Authors: Frantisek Odvarka
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Based on the data from the Moravian Karst, the influence of the calcite speleothem growth by selected meteorological factors was evaluated. External temperature was determined as one of the main factors influencing speleothem growth in Moravian Karst. This factor significantly influences the CO₂ concentration in soil/epikarst, and cave atmosphere in the Moravian Karst and significantly contributes to the changes in the CO₂ partial pressure differences between soil/epikarst and cave atmosphere in Moravian Karst, which determines the drip water supersaturation with respect to the calcite and quantity of precipitated calcite in the Moravian Karst cave environment. External air temperatures and cave air temperatures were measured using a COMET S3120 data logger, which can measure temperatures in the range from -30 to +80 °C with an accuracy of ± 0.4 °C. CO₂ concentrations in the cave and soils were measured with a FT A600 CO₂H Ahlborn probe (value range 0 ppmv to 10,000 ppmv, accuracy 1 ppmv), which was connected to the data logger ALMEMO 2290-4, V5 Ahlborn. The soil temperature was measured with a FHA646E1 Ahlborn probe (temperature range -20 to 70 °C, accuracy ± 0.4 °C) connected to an ALMEMO 2290-4 V5 Ahlborn data logger. The airflow velocities into and out of the cave were monitored by a FVA395 TH4 Thermo anemometer (speed range from 0.05 to 2 m s⁻¹, accuracy ± 0.04 m s⁻¹), which was connected to the ALMEMO 2590-4 V5 Ahlborn data logger for recording. The flow was measured in the lower and upper entrance of the Imperial Cave. The data were analyzed in MS Office Excel 2019 and PHREEQC.Keywords: speleothem growth, carbon dioxide partial pressure, Moravian Karst, external temperature
Procedia PDF Downloads 1443799 Histological and Morphometric Studies of the Liver of Goats Aborted
Authors: Toumi Farah, Charallah Salima
Abstract:
In the Algerian Sahara, goat farming is predominant, and it’s associated with other types of breeding, particularly camel and sheep; it also constitutes a significant proportion of breeding exclusively goat. This Saharan goat is a small ruminant with a black dress with white’s spots, hanging ears, and a coat more or less long. It is known for its hardiness and resistance to adverse conditions of arid zones and its perfect ecophysiological adaptation to harsh environmental conditions. However, pregnancy alterations, particularly abortion, degrade its productivity and cause economic losses, having both direct and indirect effects on animal production, like the costs of veterinary interventions and the reconstitution of livestock. The purpose of this work is to study the histological aspect of the liver of goats’ aborted living under nomadic herds in the region of Béni-Abbès (30° 7' N, 2° 10 'O). The organs were collected in physiological serum, rinsed, and then fixed with formaldehyde (37°, diluted at 10%). After that, these samples were processed for a topographic study. The morphometric study of the liver was performed by using an image analysis and processing software "Image J"; the various measurements obtained are intended to specify the supposed stage of development according to the body weight. The histological structure of the liver shows that the hepatic parenchyma consists of vascular conjunctive spaces surrounded by Glisson’s capsule. The sinusoids and hepatic portal vein are full of red blood cells, representing sinusoidal congestion and a thrombosed vein. At high magnification, the blood vessels show the presence of vascular thrombosis and haemorrhage in some areas of the hepatic parenchyma. Morphometric analysis shows that the number of liver parenchymal cells and the diameter of liver vessels vary according to the stage of development. The results obtained will provide details of the anatomical and cellular elements that can be used in the diagnosis of early or late abortion and late embryonic death. It would be interesting to find, by immunohistochemistry, some inflammatory markers useful for monitoring the progress of pregnancy and bioindicators of fetomaternal distress.Keywords: aborting goat, arid zone, liver, histopathology
Procedia PDF Downloads 99