Search results for: secondary flow
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7717

Search results for: secondary flow

1027 A Study of the Interactions between the Inter-City Traffic System and the Spatial Structure Evolution in the Yangtze River Delta from Time and Space Dimensions

Authors: Zhang Cong, Cai Runlin, Jia Fengjiao

Abstract:

The evolution of the urban agglomeration spatial structure requires strong support of the inter-city traffic system. And the inter-city traffic system can not only meet the demand of the urban agglomeration transportation but also guide the economic development. To correctly understand the relationship between inter-city traffic planning and urban agglomeration can help the urban agglomeration coordinated developing with the inter-city traffic system. The Yangtze River Delta is one of the most representative urban agglomerations in China with strong economic vitality, high city levels, diversified urban space form, and improved transport infrastructure. With the promotion of industrial division in the Yangtze River Delta and the regional travel facilitation brought by inter-city traffic, the urban agglomeration is characterized by highly increasing of inter-city transportation demand, the urbanization of regional traffic, adjacent regional transportation links breaking administrative boundaries, the networked channels and so on. Therefore, the development of inter-city traffic system presents new trends and challenges. This paper studies the interactions between inter-city traffic system and regional economic growth, regional factor flow, and regional spatial structure evolution in the Yangtze River Delta from two dimensions of time and space. On this basis, the adaptability of inter-city traffic development mode and urban agglomeration space structure is analyzed. First of all, the coordination between urban agglomeration planning and inter-city traffic planning is judged from the planning level. Secondly, the coordination between inter-city traffic elements and industries and population distributions is judged from the perspective of space. Finally, the coordination of the cross-regional planning and construction of inter-city traffic system is judged. The conclusions can provide an empirical reference for intercity traffic planning in Yangtze River Delta region and other urban agglomerations, and it is also of great significance to optimize the allocation of urban agglomerations and the overall operational efficiency.

Keywords: evolution, interaction, inter-city traffic system, spatial structure

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1026 Wharton's Jelly-Derived Mesenchymal Stem Cells Modulate Heart Rate Variability and Improve Baroreflex Sensitivity in Septic Rats

Authors: Cóndor C. José, Rodrigues E. Camila, Noronha L. Irene, Dos Santos Fernando, Irigoyen M. Claudia, Andrade Lúcia

Abstract:

Sepsis induces alterations in hemodynamics and autonomic nervous system (ASN). The autonomic activity can be calculated by measuring heart rate variability (HRV) that represents the complex interplay between ASN and cardiac pacemaker cells. Wharton’s jelly mesenchymal stem cells (WJ-MSCs) are known to express genes and secreted factors involved in neuroprotective and immunological effects, also to improve the survival in experimental septic animals. We hypothesized, that WJ-MSCs present an important role in the autonomic activity and in the hemodynamic effects in a cecal ligation and puncture (CLP) model of sepsis. Methods: We used flow cytometry to evaluate WJ-MSCs phenotypes. We divided Wistar rats into groups: sham (shamoperated); CLP; and CLP+MSC (106 WJ-MSCs, i.p., 6 h after CLP). At 24 h post-CLP, we recorded the systolic arterial pressure (SAP) and heart rate (HR) over 20 min. The spectral analysis of HR and SAP; also the spontaneous baroreflex sensitivity (measure by bradycardic and tachycardic responses) were evaluated after recording. The one-way ANOVA and the post hoc Student– Newman– Keuls tests (P< 0.05) were used to data comparison Results: WJ-MSCs were negative for CD3, CD34, CD45 and HLA-DR, whereas they were positive for CD73, CD90 and CD105. The CLP group showed a reduction in variance of overall variability and in high-frequency power of HR (heart parasympathetic activity); furthermore, there is a low-frequency reduction of SAP (blood vessels sympathetic activity). The treatment with WJ-MSCs improved the autonomic activity by increasing the high and lowfrequency power; and restore the baroreflex sensitive. Conclusions: WJ-MSCs attenuate the impairment of autonomic control of the heart and vessels and might therefore play a protective role in sepsis. (Supported by FAPESP).

Keywords: baroreflex response, heart rate variability, sepsis, wharton’s jelly-derived mesenchymal stem cells

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1025 Catalytic Hydrothermal Decarboxylation of Lipid from Activated Sludge for Renewable Diesel Production

Authors: Ifeanyichukwu Edeh, Tim Overton, Steve Bowra

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Currently biodiesel is produced from plant oils or animal’s fats by a liquid-phase catalysed transesterification process at low temperature. Although biodiesel is renewable and to a large extent sustainable, inherent properties such as poor cold flow, low oxidation stability, low cetane value restrict application to blends with fossil fuels. An alternative to biodiesel is renewable diesel produced by catalytic hydrotreating of oils and fats and is considered a drop in fuel because its properties are similar to petroleum diesel. In addition to developing alternative productions routes there is continued interest in reducing the cost of the feed stock, waste cooking oils and fats are increasingly used as the feedstocks due to low cost. However, use of oils and fat are highly adulterated resulting in high free fatty acid content which turn impacts on the efficiency of FAME production. Therefore, in light of the need to develop, alternative lipid feed stocks and related efficient catalysis the present study investigates the potential of producing renewable diesel from the lipids-extracted from activated sludge, a waste water treatment by-product, through catalytic hydrothermal decarboxylation. The microbial lipids were first extracted from the activated sludge using the Folch et al method before hydrothermal decarboxylation reactions were carried out using palladium (Pd/C) and platinum (Pt/C) on activated carbon as the catalysts in a batch reactor. The impact of three temperatures 290, 300, 330 °C and residence time between 30 min and 4hrs was assessed. At the end of the reaction, the products were recovered using organic solvents and characterized using gas chromatography (GC). The principle products of the reaction were pentadecane and heptadecane. The highest yields of pentadecane and heptadecane from lipid-extract were 23.23% and 15.21%, respectively. These yields were obtained at 290 °C and residence time 1h using Pt/C. To the best of our knowledge, the current work is the first investigation on the hydrothermal decarboxylation of lipid-extract from activated sludge.

Keywords: activated sludge, lipid, hydrothermal decarboxylation, renewable diesel

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1024 Twist2 Is a Key Regulator of Cell Proliferation in Acute Lymphoblastic Leukaemia

Authors: Magdalena Rusady Goey, Gordon Strathdee, Neil Perkins

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Background: Acute lymphoblastic leukaemia (ALL) is the most frequent type of childhood malignancy, accounting for 25% of all cases. TWIST2, a basic helix-loop-helix transcription factor, has been implicated in ALL development. Prior studies found that TWIST2 undergoes epigenetic silencing in more than 50% cases of ALL through promoter hypermethylation and suggested that re-expression of TWIST2 may inhibit cell growth/survival of leukaemia cell lines. TWIST2 has also been implicated as a regulator of NF-kappaB activity, which is constitutively active in leukaemia. Here, we use a lentiviral transductions system to confirm the importance of TWIST2 in controlling leukaemia cell growth and to investigate whether this is achieved through altered regulation of NF-kappaB activity. Method: Re-expression of TWIST2 in leukaemia cell lines was achieved using lentiviral-based transduction. The lentiviral vector also expresses enhanced green fluorescent protein (eGFP), allowing transduced cells to be tracked using flow cytometry. Analysis of apoptosis and cell proliferation were done using annexinV and VPD450 staining, respectively. Result and Discussion: TWIST2-expressing cells were rapidly depleted from a mixed population in ALL cell lines (NALM6 and Reh), indicating that TWIST2 inhibited cell growth/survival of ALL cells. In contrast, myeloid cell lines (HL60 and K562) were comparatively insensitive to TWIST2 re-expression. Analysis of apoptosis and cell proliferation found no significant induction of apoptosis, but did find a rapid induction of proliferation arrest in TWIST2-expressing Reh and NALM6 cells. Initial experiment with NF-kappaB inhibitor demonstrated that inhibition of NF-kappaB has similar impact on cell proliferation in the ALL cell lines, suggesting that TWITST2 may induce cell proliferation arrest through inhibition of NF-kappaB. Conclusion: The results of this study suggest that epigenetic inactivation of TWIST2 in primary ALL leads to increased proliferation, potentially by altering the regulation of NF-kappaB.

Keywords: leukaemia, acute lymphoblastic leukaemia, NF-kappaB, TWIST2, lentivirus

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1023 Tree Resistance to Wind Storm: The Effects of Soil Saturation on Tree Anchorage of Young Pinus pinaster

Authors: P. Defossez, J. M. Bonnefond, D. Garrigou, P. Trichet, F. Danjon

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Windstorm damage to European forests has ecological, social and economic consequences of major importance. Most trees during storms are uprooted. While a large amount of work has been done over the last decade on understanding the aerial tree response to turbulent wind flow, much less is known about the root-soil interface, and the impact of soil moisture and root-soil system fatiguing on tree uprooting. Anchorage strength is expected to be reduced by water-logging and heavy rain during storms due to soil strength decrease with soil water content. Our paper is focused on the maritime pine cultivated on sandy soil, as a representative species of the Forêt des Landes, the largest cultivated forest in Europe. This study aims at providing knowledge on the effects of soil saturation on root anchorage. Pulling experiments on trees were performed to characterize the resistance to wind by measuring the critical bending moment (Mc). Pulling tests were performed on 12 maritime pines of 13-years old for two unsaturated soil conditions that represent the soil conditions expected in winter when wind storms occur in France (w=11.46 to 23.34 % gg⁻¹). A magnetic field digitizing technique was used to characterize the three-dimensional architecture of root systems. The soil mechanical properties as function of soil water content were characterized by laboratory mechanical measurements as function of soil water content and soil porosity on remolded samples using direct shear tests at low confining pressure ( < 15 kPa). Remarkably Mc did not depend on w but mainly on the root system morphology. We suggested that the importance of soil water conditions on tree anchorage depends on the tree size. This study gives a new insight on young tree anchorage: roots may sustain by themselves anchorage, whereas adhesion between roots and surrounding soil may be negligible in sandy soil.

Keywords: roots, sandy soil, shear strength, tree anchorage, unsaturated soil

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1022 The Evaluation of the Cognitive Training Program for Older Adults with Mild Cognitive Impairment: Protocol of a Randomized Controlled Study

Authors: Hui-Ling Yang, Kuei-Ru Chou

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Background: Studies show that cognitive training can effectively delay cognitive failure. However, there are several gaps in the previous studies of cognitive training in mild cognitive impairment: 1) previous studies enrolled mostly healthy older adults, with few recruiting older adults with cognitive impairment; 2) they also had limited generalizability and lacked long-term follow-up data and measurements of the activities of daily living functional impact. Moreover, only 37% were randomized controlled trials (RCT). 3) Limited cognitive training has been specifically developed for mild cognitive impairment. Objective: This study sought to investigate the changes in cognitive function, activities of daily living and degree of depressive symptoms in older adults with mild cognitive impairment after cognitive training. Methods: This double-blind randomized controlled study has a 2-arm parallel group design. Study subjects are older adults diagnosed with mild cognitive impairment in residential care facilities. 124 subjects will be randomized by the permuted block randomization, into intervention group (Cognitive training, CT), or active control group (Passive information activities, PIA). Therapeutic adherence, sample attrition rate, medication compliance and adverse events will be monitored during the study period, and missing data analyzed using intent-to-treat analysis (ITT). Results: Training sessions of the CT group are 45 minutes/day, 3 days/week, for 12 weeks (36 sessions each). The training of active control group is the same as CT group (45min/day, 3days/week, for 12 weeks, for a total of 36 sessions). The primary outcome is cognitive function, using the Mini-Mental Status Examination (MMSE); the secondary outcome indicators are: 1) activities of daily living, using the Lawton’s Instrumental Activities of Daily Living (IADLs) and 2) degree of depressive symptoms, using the Geriatric Depression Scale-Short form (GDS-SF). Latent growth curve modeling will be used in the repeated measures statistical analysis to estimate the trajectory of improvement by examining the rate and pattern of change in cognitive functions, activities of daily living and degree of depressive symptoms for intervention efficacy over time, and the effects will be evaluated immediate post-test, 3 months, 6 months and one year after the last session. Conclusions: We constructed a rigorous CT program adhering to the Consolidated Standards of Reporting Trials (CONSORT) reporting guidelines. We expect to determine the improvement in cognitive function, activities of daily living and degree of depressive symptoms of older adults with mild cognitive impairment after using the CT.

Keywords: mild cognitive impairment, cognitive training, randomized controlled study

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1021 Sludge Densification: Emerging and Efficient Way to Look at Biological Nutrient Removal Treatment

Authors: Raj Chavan

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Currently, there are over 14,500 Water Resource Recovery Facilities (WRRFs) in the United States, with ~35% of them having some type of nutrient limits in place. These WRRFs account for about 1% of overall power demand and 2% of total greenhouse gas emissions (GHG) in the United States and contribute for 10 to 15% of the overall nutrient load to surface rivers in the United States. The evolution of densification technologies toward more compact and energy-efficient nutrient removal processes has been impacted by a number of factors. Existing facilities that require capacity expansion or biomass densification for higher treatability within the same footprint are being subjected to more stringent requirements relating to nutrient removal prior to surface water discharge. Densification of activated sludge has received recent widespread interest as a means for achieving process intensification and nutrient removal at WRRFs. At the core of the technology are the aerobic sludge granules where the biological processes occur. There is considerable interest in the prospect of producing granular sludge in continuous (or traditional) activated sludge processes (CAS) or densification of biomass by moving activated sludge flocs to a denser aggregate of biomass as a highly effective technique of intensification. This presentation will provide a fundamental understanding of densification by presenting insights and practical issues. The topics that will be discussed include methods used to generate and retain densified granules; the mechanisms that allow biological flocs to densify; the role that physical selectors play in the densification of biological flocs; some viable ways for managing biological flocs that have become densified; effects of physical selection design parameters on the retention of densified biological flocs and finally some operational solutions for customizing the flocs and granules required to meet performance and capacity targets. In addition, it will present some case studies where biological and physical parameters were used to generate aerobic granular sludge in the continuous flow system.

Keywords: densification, aerobic granular sludge, nutrient removal, intensification

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1020 Enhancing Algal Bacterial Photobioreactor Efficiency: Nutrient Removal and Cost Analysis Comparison for Light Source Optimization

Authors: Shahrukh Ahmad, Purnendu Bose

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Algal-Bacterial photobioreactors (ABPBRs) have emerged as a promising technology for sustainable biomass production and wastewater treatment. Nutrient removal is seldom done in sewage treatment plants and large volumes of wastewater which still have nutrients are being discharged and that can lead to eutrophication. That is why ABPBR plays a vital role in wastewater treatment. However, improving the efficiency of ABPBR remains a significant challenge. This study aims to enhance ABPBR efficiency by focusing on two key aspects: nutrient removal and cost-effective optimization of the light source. By integrating nutrient removal and cost analysis for light source optimization, this study proposes practical strategies for improving ABPBR efficiency. To reduce organic carbon and convert ammonia to nitrates, domestic wastewater from a 130 MLD sewage treatment plant (STP) was aerated with a hydraulic retention time (HRT) of 2 days. The treated supernatant had an approximate nitrate and phosphate values of 16 ppm as N and 6 ppm as P, respectively. This supernatant was then fed into the ABPBR, and the removal of nutrients (nitrate as N and phosphate as P) was observed using different colored LED bulbs, namely white, blue, red, yellow, and green. The ABPBR operated with a 9-hour light and 3-hour dark cycle, using only one color of bulbs per cycle. The study found that the white LED bulb, with a photosynthetic photon flux density (PPFD) value of 82.61 µmol.m-2 .sec-1 , exhibited the highest removal efficiency. It achieved a removal rate of 91.56% for nitrate and 86.44% for phosphate, surpassing the other colored bulbs. Conversely, the green LED bulbs showed the lowest removal efficiencies, with 58.08% for nitrate and 47.48% for phosphate at an HRT of 5 days. The quantum PAR (Photosynthetic Active Radiation) meter measured the photosynthetic photon flux density for each colored bulb setting inside the photo chamber, confirming that white LED bulbs operated at a wider wavelength band than the others. Furthermore, a cost comparison was conducted for each colored bulb setting. The study revealed that the white LED bulb had the lowest average cost (Indian Rupee)/light intensity (µmol.m-2 .sec-1 ) value at 19.40, while the green LED bulbs had the highest average cost (INR)/light intensity (µmol.m-2 .sec-1 ) value at 115.11. Based on these comparative tests, it was concluded that the white LED bulbs were the most efficient and costeffective light source for an algal photobioreactor. They can be effectively utilized for nutrient removal from secondary treated wastewater which helps in improving the overall wastewater quality before it is discharged back into the environment.

Keywords: algal bacterial photobioreactor, domestic wastewater, nutrient removal, led bulbs

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1019 Antimicrobial Action and Its Underlying Mechanism by Methanolic Seed Extract of Syzygium cumini on Bacillus subtilis

Authors: Alok Kumar Yadav, Saurabh Saraswat, Preeti Sirohi, Manjoo Rani, Sameer Srivastava, Manish Pratap Singh, Nand K. Singh

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The development of antibiotic resistance in bacteria is increasing at an alarming rate, and this is considered as one of the most serious threats in the history of medicine, and an alternative solution should be derived so as to tackle this problem. In many countries, people use the medicinal plants for the treatment of various diseases as these are cheaper, easily available and least toxic. Syzygium cumini is used for the treatment of various kinds of diseases but their mechanism of action is not reported. The antimicrobial activity of Syzygium cumini was tested by the well diffusion assay and zone of inhibition was reported to be 20.06 mm as compared to control with MIC of 0.3 mg/ml. Genomic DNA fragmentation of Bacillus subtilis revealed apoptosis and FE-SEM indicate cell wall cracking on several intervals of time. Propidium iodide staining results showed that few bacterial cells were stained in the control and population of stained cells increase after exposing them for various period of time. Flow cytometric kinetic data analysis on the membrane permeabilization in bacterial cell showed the significant contribution of antimicrobial potential of the seed extract on antimicrobial-induced permeabilization. Two components of Syzygium cumini methanolic seed extract was found to be quite active against four enzymes like PDB ID- 1W5D, 4OX3, 3MFD and 5E2F which have a very crucial role in membrane synthesis in Bacillus subtilis by in silico analysis. Through in silico analysis, lupeol showed highest binding energy for macromolecule 1W5D and 4OX3 whereas stigmasterol showed the highest binding energy for macromolecule 3MFD and 5E2F respectively. It showed that methanolic seed extract of Syzygium cumini can be used for the inhibition of foodborne infections caused by Bacillus subtilis and also as an alternative of prevalent antibiotics.

Keywords: antibiotics, Bacillus subtilis, inhibition, Syzygium cumini

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1018 Stereological Evaluation of Liver of Rabbit Fetuses After Transplantation of Human Wharton’s Jelly-Derived Mesenchymal Stromal/Stem Cells

Authors: Zahra Khodabandeh, Leila Rezaeian, Mohammad Amin Edalatmanesh, Asghar Mogheiseh, Nader Tanideh, Mehdi Dianatpour, Shahrokh Zare, Hossein Bordbar, Neda Baghban, Amin Tamadon

Abstract:

Background: In-utero xenotransplantation of stem cells in abnormal fetuses effectively treats several genetic illnesses. Objective: The current research aimed to evaluate structural and morphological alterations in the liver of rabbit fetuses following xenotransplantation of human Wharton’s jelly-derived mesenchymal stromal cells (hWJ-MSCs) using a stereological technique. Methods: hWJ-MSCs were isolated from the human umbilical cord, and their authenticity was established by flow cytometry and differentiation. At gestational day 14, the rabbits were anesthetized, and hWJ-MSCs were injected into the uteri of 24 fetuses. Twenty-two fetuses were born successfully. Ten rabbit liver specimens were prepared from injected fetuses, including eight rabbits on day three following birth and two rabbits on the 21st post-natal day. The non-injected fetuses were considered positive controls. The livers of the control and hWJ-MSCs-treated rabbits were fixed, processed, stained, and examined through stereological approaches. Results: In the hWJ-MSCs-treated group, the mean liver weight and volume increased by 42% and 78% compared to the control group. The total volume of the hepatocytes increased by 63% and that of sinusoids by threefold in the treated rabbits. The total volume of the central veins increased by 70%. The total number corresponding to hepatocytes in the experimental group increased by 112% compared to the rabbits in the control. The total volume of the hepatocyte nuclei in the experimental group increased by 117% compared to the rabbits in the control. Conclusion: After xenotransplantation of human MSCs, host tissue microenvironments (here, the rabbit liver) were altered, and these included quantitative factors corresponding to the liver tissue and hepatocyte morphometric indices.

Keywords: xenotransplantation, mesenchymal stromal, stem cell, Wharton ‘s jelly, liver

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1017 The Effect of Air Injection in Irrigation Water on Sugar Beet Yield

Authors: Yusuf Ersoy Yildirim, Ismail Tas, Ceren Gorgusen, Tugba Yeter, Aysegul Boyacioglu, K. Mehmet Tugrul, Murat Tugrul, Ayten Namli, H. Sabri Ozturk, M. Onur Akca

Abstract:

In recent years, a lot of research has been done for the sustainable use of scarce resources in the world. Especially, effective and sustainable use of water resources has been researched for many years. Sub-surface drip irrigation (SDI) is one of the most effective irrigation methods in which efficient and sustainable use of irrigation water can be achieved. When the literature is taken into consideration, it is often emphasized that, besides its numerous advantages, it also allows the application of irrigation water to the plant root zone along with air. It is stated in different studies that the air applied to the plant root zone with irrigation water has a positive effect on the root zone. Plants need sufficient oxygen for root respiration as well as for the metabolic functions of the roots. Decreased root respiration due to low oxygen content reduces transpiration, disrupts the flow of ions, and increases the ingress of salt reaching toxic levels, seriously affecting plant growth. Lack of oxygen (Hypoxia) can affect the survival of plants. The lack of oxygen in the soil is related to the exchange of gases in the soil with the gases in the atmosphere. Soil aeration is an important physical parameter of a soil. It is highly dynamic and is closely related to the amount of water in the soil and its bulk weight. Subsurface drip irrigation; It has higher water use efficiency compared to irrigation methods such as furrow irrigation and sprinkler irrigation. However, in heavy clay soils, subsurface drip irrigation creates continuous wetting fronts that predispose the rhizosphere region to hypoxia or anoxia. With subsurface drip irrigation, the oxygen is limited for root microbial respiration and root development, with the continuous spreading of water to a certain region of the root zone. In this study, the change in sugar beet yield caused by air application in the SDI system will be explained.

Keywords: sugar beet, subsurface drip irrigation, air application, irrigation efficiency

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1016 Learning from Long COVID: How Healthcare Needs to Change for Contested Illnesses

Authors: David Tennison

Abstract:

In the wake of the Covid-19 pandemic, a new chronic illness emerged onto the global stage: Long Covid. Long Covid presents with several symptoms commonly seen in other poorly-understood illnesses, such as fibromyalgia (FM) and myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS). However, while Long Covid has swiftly become a recognised illness, FM and ME/CFS are still seen as contested, which impacts patient care and healthcare experiences. This study aims to examine what the differences are between Long Covid and FM; and if the Long Covid case can provide guidance for how to address the healthcare challenge of contested illnesses. To address this question, this study performed comprehensive research into the history of FM; our current biomedical understanding of it; and available healthcare interventions (within the context of the UK NHS). Analysis was undertaken of the stigma and stereotypes around FM, and a comparison made between FM and the emerging Long Covid literature, along with the healthcare response to Long Covid. This study finds that healthcare for chronic contested illnesses in the UK is vastly insufficient - in terms of pharmaceutical and holistic interventions, and the provision of secondary care options. Interestingly, for Long Covid, many of the treatment suggestions are pulled directly from those used for contested illnesses. The key difference is in terms of funding and momentum – Long Covid has generated exponentially more interest and research in a short time than there has been in the last few decades of contested illness research. This stands to help people with FM and ME/CFS – for example, research has recently been funded into “brain fog”, a previously elusive and misunderstood symptom. FM is culturally regarded as a “women’s disease” and FM stigma stems from notions of “hysteria”. A key finding is that the idea of FM affecting women disproportionally is not reflected in modern population studies. Emerging data on Long Covid also suggests a slight leaning towards more female patients, however it is less feminised, potentially due to it emerging in the global historical moment of the pandemic. Another key difference is that FM is rated as an extremely low-prestige illness by healthcare professionals, while it was in large part due to the advocacy of affected healthcare professionals that Long Covid was so quickly recognised by science and medicine. In conclusion, Long Covid (and the risk of future pandemics and post-viral illnesses) highlight a crucial need for implementing new, and reinforcing existing, care networks for chronic illnesses. The difference in how contested illnesses like FM, and new ones like Long Covid are treated have a lot to do with the historical moment in which they emerge – but cultural stereotypes, from within and without medicine, need updating. Particularly as they contribute to disease stigma that causes genuine harm to patients. However, widespread understanding and acceptance of Long Covid could help fight contested illness stigma, and the attention, funding and research into Long Covid may actually help raise the profile of contested illnesses and uncover answers about their symptomatology.

Keywords: long COVID, fibromyalgia, myalgic encephalomyelitis, chronic fatigue syndrome, NHS, healthcare, contested illnesses, chronic illnesses, COVID-19 pandemic

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1015 Experimental Modeling of Spray and Water Sheet Formation Due to Wave Interactions with Vertical and Slant Bow-Shaped Model

Authors: Armin Bodaghkhani, Bruce Colbourne, Yuri S. Muzychka

Abstract:

The process of spray-cloud formation and flow kinematics produced from breaking wave impact on vertical and slant lab-scale bow-shaped models were experimentally investigated. Bubble Image Velocimetry (BIV) and Image Processing (IP) techniques were applied to study the various types of wave-model impacts. Different wave characteristics were generated in a tow tank to investigate the effects of wave characteristics, such as wave phase velocity, wave steepness on droplet velocities, and behavior of the process of spray cloud formation. The phase ensemble-averaged vertical velocity and turbulent intensity were computed. A high-speed camera and diffused LED backlights were utilized to capture images for further post processing. Various pressure sensors and capacitive wave probes were used to measure the wave impact pressure and the free surface profile at different locations of the model and wave-tank, respectively. Droplet sizes and velocities were measured using BIV and IP techniques to trace bubbles and droplets in order to measure their velocities and sizes by correlating the texture in these images. The impact pressure and droplet size distributions were compared to several previously experimental models, and satisfactory agreements were achieved. The distribution of droplets in front of both models are demonstrated. Due to the highly transient process of spray formation, the drag coefficient for several stages of this transient displacement for various droplet size ranges and different Reynolds number were calculated based on the ensemble average method. From the experimental results, the slant model produces less spray in comparison with the vertical model, and the droplet velocities generated from the wave impact with the slant model have a lower velocity as compared with the vertical model.

Keywords: spray charachteristics, droplet size and velocity, wave-body interactions, bubble image velocimetry, image processing

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1014 The Effect of Metal-Organic Framework Pore Size to Hydrogen Generation of Ammonia Borane via Nanoconfinement

Authors: Jing-Yang Chung, Chi-Wei Liao, Jing Li, Bor Kae Chang, Cheng-Yu Wang

Abstract:

Chemical hydride ammonia borane (AB, NH3BH3) draws attentions to hydrogen energy researches for its high theoretical gravimetrical capacity (19.6 wt%). Nevertheless, the elevated AB decomposition temperatures (Td) and unwanted byproducts are main hurdles in practical application. It was reported that the byproducts and Td can be reduced with nanoconfinement technique, in which AB molecules are confined in porous materials, such as porous carbon, zeolite, metal-organic frameworks (MOFs), etc. Although nanoconfinement empirically shows effectiveness on hydrogen generation temperature reduction in AB, the theoretical mechanism is debatable. Low Td was reported in AB@IRMOF-1 (Zn4O(BDC)3, BDC = benzenedicarboxylate), where Zn atoms form closed metal clusters secondary building unit (SBU) with no exposed active sites. Other than nanosized hydride, it was also observed that catalyst addition facilitates AB decomposition in the composite of Li-catalyzed carbon CMK-3, MOF JUC-32-Y with exposed Y3+, etc. It is believed that nanosized AB is critical for lowering Td, while active sites eliminate byproducts. Nonetheless, some researchers claimed that it is the catalytic sites that are the critical factor to reduce Td, instead of the hydride size. The group physically ground AB with ZIF-8 (zeolitic imidazolate frameworks, (Zn(2-methylimidazolate)2)), and found similar reduced Td phenomenon, even though AB molecules were not ‘confined’ or forming nanoparticles by physical hand grinding. It shows the catalytic reaction, not nanoconfinement, leads to AB dehydrogenation promotion. In this research, we explored the possible criteria of hydrogen production temperature from nanoconfined AB in MOFs with different pore sizes and active sites. MOFs with metal SBU such as Zn (IRMOF), Zr (UiO), and Al (MIL-53), accompanying with various organic ligands (BDC and BPDC; BPDC = biphenyldicarboxylate) were modified with AB. Excess MOFs were used for AB size constrained in micropores estimated by revisiting Horvath-Kawazoe model. AB dissolved in methanol was added to MOFs crystalline with MOF pore volume to AB ratio 4:1, and the slurry was dried under vacuum to collect AB@MOF powders. With TPD-MS (temperature programmed desorption with mass spectroscopy), we observed Td was reduced with smaller MOF pores. For example, it was reduced from 100°C to 64°C when MOF micropore ~1 nm, while ~90°C with pore size up to 5 nm. The behavior of Td as a function of AB crystalline radius obeys thermodynamics when the Gibbs free energy of AB decomposition is zero, and no obvious correlation with metal type was observed. In conclusion, we discovered Td of AB is proportional to the reciprocal of MOF pore size, possibly stronger than the effect of active sites.

Keywords: ammonia borane, chemical hydride, metal-organic framework, nanoconfinement

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1013 Examining Kokugaku as a Pattern of Defining Identity in Global Comparison

Authors: Mária Ildikó Farkas

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Kokugaku of the Edo period can be seen as a key factor of defining cultural (and national) identity in the 18th and early 19th century based on Japanese cultural heritage. Kokugaku focused on Japanese classics, on exploring, studying and reviving (or even inventing) ancient Japanese language, literature, myths, history and also political ideology. ‘Japanese culture’ as such was distinguished from Chinese (and all other) cultures, ‘Japanese identity’ was thus defined. Meiji scholars used kokugaku conceptions of Japan to construct a modern national identity based on the premodern and culturalist conceptions of community. The Japanese cultural movement of the 18-19th centuries (kokugaku) of defining cultural and national identity before modernization can be compared not to the development of Western Europe (where national identity strongly attached to modern nation states) or other parts of Asia (where these emerged after the Western colonization), but rather with the ‘national awakening’ movements of the peoples of East Central Europe, a comparison which have not been dealt with in the secondary literature yet. The role of a common language, culture, history and myths in the process of defining cultural identity – following mainly Miroslav Hroch’s comparative and interdisciplinary theory of national development – can be examined compared to the movements of defining identity of the peoples of East Central Europe (18th-19th c). In the shadow of a cultural and/or political ‘monolith’ (China for Japan and Germany for Central Europe), before modernity, ethnic groups or communities started to evolve their own identities with cultural movements focusing on their own language and culture, thus creating their cultural identity, and in the end, a new sense of community, the nation. Comparing actual texts (‘narratives’) of the kokugaku scholars and Central European writers of the nation building period (18th and early 19th centuries) can reveal the similarities of the discourses of deliberate searches for identity. Similar motives of argument can be identified in these narratives: ‘language’ as the primary bearer of collective identity, the role of language in culture, ‘culture’ as the main common attribute of the community; and similar aspirations to explore, search and develop native language, ‘genuine’ culture, ‘original’ traditions. This comparative research offering ‘development patterns’ for interpretation can help us understand processes that may be ambiguously considered ‘backward’ or even ‘deleterious’ (e.g. cultural nationalism) or just ‘unique’. ‘Cultural identity’ played a very important role in the formation of national identity during modernization especially in the case of non-Western communities, who had to face the danger of losing their identities in the course of ‘Westernization’ accompanying modernization.

Keywords: cultural identity, Japanese modernization, kokugaku, national awakening

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1012 Double Row Taper Roller Bearing Wheel-end System in Rigid Rear Drive Axle in Heavy Duty SUV Passenger Vehicle

Authors: Mohd Imtiaz S, Saurabh Jain, Pothiraj K.

Abstract:

In today’s highly competitive passenger vehicle market, comfortable driving experience is one of the key parameters significantly weighed by the customer. Smooth ride and handling of the vehicle with exceptionally reliable wheel end solution is a paramount requirement in passenger Sports Utility Vehicle (SUV) vehicles subjected to challenging terrains and loads with rigid rear drive axle configuration. Traditional wheel-end bearing systems in passenger segment rigid rear drive axle utilizes the semi-floating layout, which imparts vertical bending loads and torsion to the axle shafts. The wheel-end bearing is usually a Single or Double Row Deep-Groove Ball Bearing (DRDGBB) or Double Row Angular Contact Ball Bearing (DRACBB). This solution is cost effective and simple in architecture. However, it lacks effectiveness against the heavy loads subjected to a SUV vehicle, especially the axial trust at high-speed cornering. This paper describes the solution of Double Row Taper Roller Bearing (DRTRB) wheel-end for a SUV vehicle in the rigid rear drive axle and improvement in terms of maximizing its load carrying capacity along with better reliability in terms of axial thrust in high-speed cornering. It describes the advantage of geometry of DRTRB over DRDGBB and DRACBB highlighting contact and load flow. The paper also highlights the vehicle level considerations affecting the B10 life of the bearing system for better selection of the DRTRB wheel-ends systems. This paper also describes real time vehicle level results along with theoretical improvements.

Keywords: axial thrust, b10 life, deep-groove ball bearing, taper roller bearing, semi-floating layout.

Procedia PDF Downloads 70
1011 Numerical Methodology to Support the Development of a Double Chamber Syringe

Authors: Lourenço Bastos, Filipa Carneiro, Bruno Vale, Rita Marques Joana Silva, Ricardo Freitas, Ângelo Marques, Sara Cortez, Alberta Coelho, Pedro Parreira, Liliana Sousa, Anabela Salgueiro, Bruno Silva

Abstract:

The process of flushing is considered to be an adequate technique to reduce the risk of infection during the clinical practice of venous catheterization. Nonetheless, there is still a lack of adhesion to this method, in part due to the complexity of this procedure. The project SeringaDuo aimed to develop an innovative double-chamber syringe for intravenous sequential administration of drugs and serums. This device served the purpose of improving the adherence to the practice, through the reduction of manipulations needed, which also improves patient safety, and though the promotion of flushing practice by health professionals, by simplifying this task. To assist on the development of this innovative syringe, a numerical methodology was developed and validated in order to predict the syringe’s mechanical and flow behavior during the fluids’ loading and administration phases, as well as to allow the material behavior evaluation during its production. For this, three commercial numerical simulation software was used, namely ABAQUS, ANSYS/FLUENT, and MOLDFLOW. This methodology aimed to evaluate the concepts feasibility and to optimize the geometries of the syringe’s components, creating this way an iterative process for product development based on numerical simulations, validated by the production of prototypes. Through this methodology, it was possible to achieve a final design that fulfils all the characteristics and specifications defined. This iterative process based on numerical simulations is a powerful tool for product development that allows obtaining fast and accurate results without the strict need for prototypes. An iterative process can be implemented, consisting of consecutive constructions and evaluations of new concepts, to obtain an optimized solution, which fulfils all the predefined specifications and requirements.

Keywords: Venous catheterization, flushing, syringe, numerical simulation

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1010 Influence of Climate Change on Landslides in Northeast India: A Case Study

Authors: G. Vishnu, T. V. Bharat

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Rainfall plays a major role in the stability of natural slopes in tropical and subtropical regions. These slopes usually have high slope angles and are stable during the dry season. The critical rainfall intensity that might trigger a landslide may not be the highest rainfall. In addition to geological discontinuities and anthropogenic factors, water content, suction, and hydraulic conductivity also play a role. A thorough geotechnical investigation with the principles of unsaturated soil mechanics is required to predict the failures in these cases. The study discusses three landslide events that had occurred in residual hills of Guwahati, India. Rainfall data analysis, history image analysis, land use, and slope maps of the region were analyzed and discussed. The landslide occurred on June (24, 26, and 28) 2020, on the respective sites, but the highest rainfall was on June (6 and 17) 2020. The factors that lead to the landslide occurrence is the combination of critical events initiated with rainfall, causing a reduction in suction. The sites consist of a mixture of rocks and soil. The slope failure occurs due to the saturation of the soil layer leading to loss of soil strength resulting in the flow of the entire soil rock mass. The land-use change, construction activities, other human and natural activities that lead to faster disintegration of rock mass may accelerate the landslide events. Landslides in these slopes are inevitable, and the development of an early warning system (EWS) to save human lives and resources is a feasible way. The actual time of failure of a slope can be better predicted by considering all these factors rather than depending solely on the rainfall intensities. An effective EWS is required with less false alarms in these regions by proper instrumentation of slope and appropriate climatic downscaling.

Keywords: early warning system, historic image analysis, slope instrumentation, unsaturated soil mechanics

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1009 Spatial Dynamic of Pico- and Nano-Phytoplankton Communities in the Mouth of the Seine River

Authors: M. Schapira, S. Françoise, F. Maheux, O. Pierre-Duplessix, E. Rabiller, B. Simon, R. Le Gendre

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Pico- and nano-phytoplankton are abundant and ecologically critical components of the autotrophic communities in the pelagic realm. While the role of physical forcing related to tidal cycle, water mass intrusion, nutrient availability, mixing and stratification on microphytoplankton blooms have been widely investigated, these are often overlooked for pico- and nano-phytoplankton especially in estuarine waters. This study investigates changes in abundances and community composition of pico- and nano-phytoplankton under different estuarine tidal conditions in the mouth of the Seine River in relation to nutrient availability, water column stratification and spatially localized currents. Samples were collected each day at high tide, over spring tide to neap tide cycle, from 21 stations homogeneously distributed in the Seine river month in May 2011. Vertical profiles of temperature, salinity and fluorescence were realized at each sampling station. Sub-surface water samples (i.e. 1 m depth) were collected for nutrients (i.e. N, P and Si), phytoplankton biomass (i.e. Chl a) and pico- and nano-phytoplankton enumeration and identification. Pico- and nano-phytoplankton populations were identified and quantified using flow cytometry. Total abundances tend to decrease from spring tide to neap tide. Samples were characterized by high abundances of Synechococcus and Cryptophyceae. The composition of the pico- and nano-phytoplankton varied greatly under the different estuarine tidal conditions. Moreover, at the scale of the river mouth, the pico- and nano-phytoplankton population exhibited patchy distribution patterns that were closely controlled by water mass intrusion from the Sea, freshwater inputs from the Seine River and the geomorphology of the river mouth. This study highlights the importance of physical forcing to the community composition of pico- and nano-phytoplankton that may be critical for the structure of the pelagic food webs in estuarine and adjacent coastal seas.

Keywords: nanophytoplancton, picophytoplankton, physical forcing, river mouth, tidal cycle

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1008 20th-Century River Course Changes and Their Relation to Sediment Carbon Distribution Patterns in the Yellow River Delta

Authors: Dongxue Li, Zhonghua Ning, Yi’na Li, Baoshan Cui, Wasner Daniel, Sebastian Dötterl

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Most of the world's coastal alluvial plains can be significant carbon (C) eservoirs in which upland sediments are deposited and bury former topsoil, thereby contributing to soil C preservation, especially in river-controlled deltas like the Yellow River Delta, China. These deltas are affected by the continuous large amount of sediment transport and strong river dynamics from the upper reaches, which makes the river course in the deltas change frequently. However, the impact of varying river course changes on C stocks in these estuary wetlands is unclear. To investigate this, we drilled five 2 m cores along a sediment deposition sequence of the Yellow River Delta, which shifted its main course flow in the delta several times throughout the 20th century. Covering 80 years of sediment deposition, we explored both soil C stocks and their potential sources, and identified key soil physicochemical and hydrometeorological variables that correlate to C density and deposition rate. Further, the spatiotemporal C distribution and its relationship with these variables was examined. Our results showed that sediments at a soil depth of 200 cm in the main courses of the Yellow River corresponded to deposition ages ranging from 1942 to 1989. The oldest course has the lowest C stocks and showed C-enriched compared with younger courses. Contributions of soil C stemming from fresh particulate organic carbon from deposited upstream sources were significantly higher than local, in-situ vegetation. In addition, the carbon of the oldest and relatively young courses tends to be affected by interaction effects of hydrometeorological and physiochemical varibales, and that of the middle courses tends to be affected by independent variables. Our findings can help prioritize conservation efforts across different river courses and provide quantitative support for global carbon emission reduction by assessing sediment carbon reservoirs.

Keywords: alluvial plains, coastal wetland, core drilling, course diversion, organic carbon, sediment deposition rate, soil deposition

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1007 Dielectric Study of Ethanol Water Mixtures at Different Concentration Using Hollow Channel Cantilever Platform

Authors: Maryam S. Ghoraishi, John E. Hawk, Thomas Thundat

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Understanding liquid properties in small scale has become important in recent decades as immerging new microelectromechanical systems (MEMS) devices have been widely used for micro pumps, drug delivery, and many other laboratory-on-microchips analysis. Often in microfluidic devices, fluids are transported electrokinetically. Therefore, extensive knowledge of fluid flow, heat transport, electrokinetics and electrochemistry are key to successful lab on a chip design. Among different microfluidic devices, recently developed hollow channel cantilever offers an ideal platform to study different fluid properties simultaneously without drastic decrease in quality factor which normally occurs when traditional cantilevers operate in the liquid phase. Using hollow channel cantilever, we monitor changes in density and viscosity of liquid while simultaneously investigating dielectric properties of alcohol water binary mixtures. Considerable research has been conducted on alcohol-water mixtures since such a mixture is a typical prototype for biomolecules, Micelle formation, and structural stability of proteins (to name a few). Here we show that hollow channel cantilever can be employed to investigate dielectric properties of ethanol/water mixtures in different concentrations. We study dynamic amplitude shifts of hollow channel cantilever oscillation at different concentrations of ethanol/water for different voltages. Our results show how interactions between solute and solvent, and possibly cluster formation, could change dielectric properties and dipole reorientation of the mixture, as well as the resulting force on the hollow cantilever. For comparison, we also examine higher conductivity ionic mixtures of sodium sulfate solution under the same conditions as low conductivity ethanol/water mixtures. We will show the results from systematic investigation of solvent effects on dielectric properties of the binary mixture. We will also address the question of resolution limits in dielectric study of analyte molecules imposed by solvent concentrations.

Keywords: dielectric constant, cantilever sensors, ethanol water mixtures, low frequency

Procedia PDF Downloads 200
1006 Study of the Energy Efficiency of Buildings under Tropical Climate with a View to Sustainable Development: Choice of Material Adapted to the Protection of the Environment

Authors: Guarry Montrose, Ted Soubdhan

Abstract:

In the context of sustainable development and climate change, the adaptation of buildings to the climatic context in hot climates is a necessity if we want to improve living conditions in housing and reduce the risks to the health and productivity of occupants due to thermal discomfort in buildings. One can find a wide variety of efficient solutions but with high costs. In developing countries, especially tropical countries, we need to appreciate a technology with a very limited cost that is affordable for everyone, energy efficient and protects the environment. Biosourced insulation is a product based on plant fibers, animal products or products from recyclable paper or clothing. Their development meets the objectives of maintaining biodiversity, reducing waste and protecting the environment. In tropical or hot countries, the aim is to protect the building from solar thermal radiation, a source of discomfort. The aim of this work is in line with the logic of energy control and environmental protection, the approach is to make the occupants of buildings comfortable, reduce their carbon dioxide emissions (CO2) and decrease their energy consumption (energy efficiency). We have chosen to study the thermo-physical properties of banana leaves and sawdust, especially their thermal conductivities, direct measurements were made using the flash method and the hot plate method. We also measured the heat flow on both sides of each sample by the hot box method. The results from these different experiences show that these materials are very efficient used as insulation. We have also conducted a building thermal simulation using banana leaves as one of the materials under Design Builder software. Air-conditioning load as well as CO2 release was used as performance indicator. When the air-conditioned building cell is protected on the roof by banana leaves and integrated into the walls with solar protection of the glazing, it saves up to 64.3% of energy and avoids 57% of CO2 emissions.

Keywords: plant fibers, tropical climates, sustainable development, waste reduction

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1005 Use of Transportation Networks to Optimize The Profit Dynamics of the Product Distribution

Authors: S. Jayasinghe, R. B. N. Dissanayake

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Optimization modelling together with the Network models and Linear Programming techniques is a powerful tool in problem solving and decision making in real world applications. This study developed a mathematical model to optimize the net profit by minimizing the transportation cost. This model focuses the transportation among decentralized production plants to a centralized distribution centre and then the distribution among island wide agencies considering the customer satisfaction as a requirement. This company produces basically 9 types of food items with 82 different varieties and 4 types of non-food items with 34 different varieties. Among 6 production plants, 4 were located near the city of Mawanella and the other 2 were located in Galewala and Anuradhapura cities which are 80 km and 150 km away from Mawanella respectively. The warehouse located in the Mawanella was the main production plant and also the only distribution plant. This plant distributes manufactured products to 39 agencies island-wide. The average values and average amount of the goods for 6 consecutive months from May 2013 to October 2013 were collected and then average demand values were calculated. The following constraints are used as the necessary requirement to satisfy the optimum condition of the model; there was one source, 39 destinations and supply and demand for all the agencies are equal. Using transport cost for a kilometer, total transport cost was calculated. Then the model was formulated using distance and flow of the distribution. Network optimization and linear programming techniques were used to originate the model while excel solver is used in solving. Results showed that company requires total transport cost of Rs. 146, 943, 034.50 to fulfil the customers’ requirement for a month. This is very much less when compared with data without using the model. Model also proved that company can reduce their transportation cost by 6% when distributing to island-wide customers. Company generally satisfies their customers’ requirements by 85%. This satisfaction can be increased up to 97% by using this model. Therefore this model can be used by other similar companies in order to reduce the transportation cost.

Keywords: mathematical model, network optimization, linear programming

Procedia PDF Downloads 345
1004 Structure Conduct and Performance of Rice Milling Industry in Sri Lanka

Authors: W. A. Nalaka Wijesooriya

Abstract:

The increasing paddy production, stabilization of domestic rice consumption and the increasing dynamism of rice processing and domestic markets call for a rethinking of the general direction of the rice milling industry in Sri Lanka. The main purpose of the study was to explore levels of concentration in rice milling industry in Polonnaruwa and Hambanthota which are the major hubs of the country for rice milling. Concentration indices reveal that the rice milling industry in Polonnaruwa operates weak oligopsony and is highly competitive in Hambanthota. According to the actual quantity of paddy milling per day, 47 % is less than 8Mt/Day, while 34 % is 8-20 Mt/day, and the rest (19%) is greater than 20 Mt/day. In Hambanthota, nearly 50% of the mills belong to the range of 8-20 Mt/day. Lack of experience of the milling industry, poor knowledge on milling technology, lack of capital and finding an output market are the major entry barriers to the industry. Major problems faced by all the rice millers are the lack of a uniform electricity supply and low quality paddy. Many of the millers emphasized that the rice ceiling price is a constraint to produce quality rice. More than 80% of the millers in Polonnaruwa which is the major parboiling rice producing area have mechanical dryers. Nearly 22% millers have modern machineries like color sorters, water jet polishers. Major paddy purchasing method of large scale millers in Polonnaruwa is through brokers. In Hambanthota major channel is miller purchasing from paddy farmers. Millers in both districts have major rice selling markets in Colombo and suburbs. Huge variation can be observed in the amount of pledge (for paddy storage) loans. There is a strong relationship among the storage ability, credit affordability and the scale of operation of rice millers. The inter annual price fluctuation ranged 30%-35%. Analysis of market margins by using series of secondary data shows that farmers’ share on rice consumer price is stable or slightly increases in both districts. In Hambanthota a greater share goes to the farmer. Only four mills which have obtained the Good Manufacturing Practices (GMP) certification from Sri Lanka Standards Institution can be found. All those millers are small quantity rice exporters. Priority should be given for the Small and medium scale millers in distribution of storage paddy of PMB during the off season. The industry needs a proper rice grading system, and it is recommended to introduce a ceiling price based on graded rice according to the standards. Both husk and rice bran were underutilized. Encouraging investment for establishing rice oil manufacturing plant in Polonnaruwa area is highly recommended. The current taxation procedure needs to be restructured in order to ensure the sustainability of the industry.

Keywords: conduct, performance, structure (SCP), rice millers

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1003 Effect of Oil Viscosity and Brine Salinity/Viscosity on Water/Oil Relative Permeability and Residual Saturations

Authors: Sami Aboujafar

Abstract:

Oil recovery in petroleum reservoirs is greatly affected by fluid-rock and fluid-fluid interactions. These interactions directly control rock wettability, capillary pressure and relative permeability curves. Laboratory core-floods and centrifuge experiments were conducted on sandstone and carbonate cores to study the effect of low and high brine salinity and viscosity and oil viscosity on residual saturations and relative permeability. Drainage and imbibition relative permeability in two phase system were measured, refined lab oils with different viscosities, heavy and light, and several brine salinities were used. Sensitivity analysis with different values for the salinity and viscosity of the fluids,, oil and water, were done to investigate the effect of these properties on water/oil relative permeability, residual oil saturation and oil recovery. Experiments were conducted on core material from viscous/heavy and light oil fields. History matching core flood simulator was used to study how the relative permeability curves and end point saturations were affected by different fluid properties using several correlations. Results were compared with field data and literature data. The results indicate that there is a correlation between the oil viscosity and/or brine salinity and residual oil saturation and water relative permeability end point. Increasing oil viscosity reduces the Krw@Sor and increases Sor. The remaining oil saturation from laboratory measurements might be too high due to experimental procedures, capillary end effect and early termination of the experiment, especially when using heavy/viscous oil. Similarly the Krw@Sor may be too low. The effect of wettability on the observed results is also discussed. A consistent relationship has been drawn between the fluid parameters, water/oil relative permeability and residual saturations, and a descriptor may be derived to define different flow behaviors. The results of this work will have application to producing fields and the methodologies developed could have wider application to sandstone and carbonate reservoirs worldwide.

Keywords: history matching core flood simulator, oil recovery, relative permeability, residual saturations

Procedia PDF Downloads 331
1002 Examining the European Central Bank's Marginal Attention to Human Rights Concerns during the Eurozone Crisis through the Lens of Organizational Culture

Authors: Hila Levi

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Respect for human rights is a fundamental element of the European Union's (EU) identity and law. Surprisingly, however, the protection of human rights has been significantly restricted in the austerity programs ordered by the International Monetary Fund (IMF), the European Central Bank (ECB) and the European Commission (EC) (often labeled 'the Troika') in return for financial aid to the crisis-hit countries. This paper focuses on the role of the ECB in the crisis management. While other international financial institutions, such as the IMF or the World Bank, may opt to neglect human rights obligations, one might expect a greater respect of human rights from the ECB, which is bound by the EU Charter of Fundamental Rights. However, this paper argues that ECB officials made no significant effort to protect human rights or strike an adequate balance between competing financial and human rights needs while coping with the crisis. ECB officials were preoccupied with the need to stabilize the economy and prevent a collapse of the Eurozone, and paid only marginal attention to human rights concerns in the design and implementation of Troikas' programs. This paper explores the role of Organizational Culture (OC) in explaining this marginalization. While International Relations (IR) research on Intergovernmental Organizations (IGOs) behavior has traditionally focused on external interests of powerful member states, and on national and economic considerations, this study focuses on particular institutions' internal factors and independent processes. OC characteristics have been identified in OC literature as an important determinant of organizational behavior. This paper suggests that cultural characteristics are also vital for the examination of IGOs, and particularly for understanding the ECB's behavior during the crisis. In order to assess the OC of the ECB and the impact it had on its policies and decisions during the Eurozone crisis, the paper uses the results of numerous qualitative interviews conducted with high-ranking officials and staff members of the ECB involved in the crisis management. It further reviews primary sources of the ECB (such as ECB statutes, and the Memoranda of Understanding signed between the crisis countries and the Troika), and secondary sources (such as the report of the UN High Commissioner for Human Rights on Austerity measures and economic, social, and cultural rights). It thus analyzes the interaction between the ECBs culture and the almost complete absence of human rights considerations in the Eurozone crisis resolution scheme. This paper highlights the importance and influence of internal ideational factors on IGOs behavior. From a more practical perspective, this paper may contribute to understanding one of the obstacles in the process of human rights implementation in international organizations, and provide instruments for better protection of social and economic rights.

Keywords: European central bank, eurozone crisis, intergovernmental organizations, organizational culture

Procedia PDF Downloads 152
1001 Model Based Design and Development of Horticultural Produce Crate from Bamboo

Authors: Sisay Wondmagegn Molla, Mulugeta Admasu Delele, Tadelle Nigusu Mekonen

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It is common to observe quality deterioration and mechanical injury of horticulture products as a result of suboptimal design and handling of the packaging systems. Society uses the old and primitive way of handling horticulture products, which is produced through trial and error This method is known to have many limitations on quality, environmental pollution, labor and cost. Ethiopia stands first in bamboo resources in Africa, which is 67 % of the African and 7 % of the world's bamboo resources. The purpose of this project was to design and develop bamboo-based ventilated horticultural produce crates using validated computational fluid dynamics (CFD). The model was used to predict the airflow and temperature distribution inside the loaded crate. The study included: sizing, collection of the thermo-physical properties, and designing and developing a CFD model of the bamboo-based ventilated horticultural crate. The designed crate (40×30×25cm) had a capacity of about 18 kg, and cold air temperature (130C) was used for cooling the fruit. Airflow in the loaded crate is far from uniform. There is a relatively high-velocity flow at the top, near inlet and near outlet sections, and a relatively low airflow near the center of the loaded crate. The predicted velocity variation within the bulk of the produce was relatively large, it was in the range of 0.04-7m/s. The vented produce package contributed the highest cooling airflow resistance. Similar to the airflow, the cooling characteristics of the product were not uniform. There was a difference in the cooling rate of the produce in the airflow direction and from the top to the bottom section of the loaded crate. The products that were located near the inlet side and top of the bulk showed a faster cooling rate than the rest of the bulk. The result showed that the produced volume average temperature was 17.9°C after a cooling period of 3 hr. It was reduced by 12.05°C. The result showed the potential of the CFD modeling approach in developing the bamboo-based design of horticultural produce crates in terms of airflow and heat transfer characteristics.

Keywords: bamboo, modeling, cooling, horticultural, packaging

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1000 Optimization of Shale Gas Production by Advanced Hydraulic Fracturing

Authors: Fazl Ullah, Rahmat Ullah

Abstract:

This paper shows a comprehensive learning focused on the optimization of gas production in shale gas reservoirs through hydraulic fracturing. Shale gas has emerged as an important unconventional vigor resource, necessitating innovative techniques to enhance its extraction. The key objective of this study is to examine the influence of fracture parameters on reservoir productivity and formulate strategies for production optimization. A sophisticated model integrating gas flow dynamics and real stress considerations is developed for hydraulic fracturing in multi-stage shale gas reservoirs. This model encompasses distinct zones: a single-porosity medium region, a dual-porosity average region, and a hydraulic fracture region. The apparent permeability of the matrix and fracture system is modeled using principles like effective stress mechanics, porous elastic medium theory, fractal dimension evolution, and fluid transport apparatuses. The developed model is then validated using field data from the Barnett and Marcellus formations, enhancing its reliability and accuracy. By solving the partial differential equation by means of COMSOL software, the research yields valuable insights into optimal fracture parameters. The findings reveal the influence of fracture length, diversion capacity, and width on gas production. For reservoirs with higher permeability, extending hydraulic fracture lengths proves beneficial, while complex fracture geometries offer potential for low-permeability reservoirs. Overall, this study contributes to a deeper understanding of hydraulic cracking dynamics in shale gas reservoirs and provides essential guidance for optimizing gas production. The research findings are instrumental for energy industry professionals, researchers, and policymakers alike, shaping the future of sustainable energy extraction from unconventional resources.

Keywords: fluid-solid coupling, apparent permeability, shale gas reservoir, fracture property, numerical simulation

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999 Disaster Management Supported by Unmanned Aerial Systems

Authors: Agoston Restas

Abstract:

Introduction: This paper describes many initiatives and shows also practical examples which happened recently using Unmanned Aerial Systems (UAS) to support disaster management. Since the operation of manned aircraft at disasters is usually not only expensive but often impossible to use as well, in many cases managers fail to use the aerial activity. UAS can be an alternative moreover cost-effective solution for supporting disaster management. Methods: This article uses thematic division of UAS applications; it is based on two key elements, one of them is the time flow of managing disasters, other is its tactical requirements. Logically UAS can be used like pre-disaster activity, activity immediately after the occurrence of a disaster and the activity after the primary disaster elimination. Paper faces different disasters, like dangerous material releases, floods, earthquakes, forest fires and human-induced disasters. Research used function analysis, practical experiments, mathematical formulas, economic analysis and also expert estimation. Author gathered international examples and used own experiences in this field as well. Results and discussion: An earthquake is a rapid escalating disaster, where, many times, there is no other way for a rapid damage assessment than aerial reconnaissance. For special rescue teams, the UAS application can help much in a rapid location selection, where enough place remained to survive for victims. Floods are typical for a slow onset disaster. In contrast, managing floods is a very complex and difficult task. It requires continuous monitoring of dykes, flooded and threatened areas. UAS can help managers largely keeping an area under observation. Forest fires are disasters, where the tactical application of UAS is already well developed. It can be used for fire detection, intervention monitoring and also for post-fire monitoring. In case of nuclear accident or hazardous material leakage, UAS is also a very effective or can be the only one tool for supporting disaster management. Paper shows some efforts using UAS to avoid human-induced disasters in low-income countries as part of health cooperation.

Keywords: disaster management, floods, forest fires, Unmanned Aerial Systems

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998 Optimization Principles of Eddy Current Separator for Mixtures with Different Particle Sizes

Authors: Cao Bin, Yuan Yi, Wang Qiang, Amor Abdelkader, Ali Reza Kamali, Diogo Montalvão

Abstract:

The study of the electrodynamic behavior of non-ferrous particles in time-varying magnetic fields is a promising area of research with wide applications, including recycling of non-ferrous metals, mechanical transmission, and space debris. The key technology for recovering non-ferrous metals is eddy current separation (ECS), which utilizes the eddy current force and torque to separate non-ferrous metals. ECS has several advantages, such as low energy consumption, large processing capacity, and no secondary pollution, making it suitable for processing various mixtures like electronic scrap, auto shredder residue, aluminum scrap, and incineration bottom ash. Improving the separation efficiency of mixtures with different particle sizes in ECS can create significant social and economic benefits. Our previous study investigated the influence of particle size on separation efficiency by combining numerical simulations and separation experiments. Pearson correlation analysis found a strong correlation between the eddy current force in simulations and the repulsion distance in experiments, which confirmed the effectiveness of our simulation model. The interaction effects between particle size and material type, rotational speed, and magnetic pole arrangement were examined. It offer valuable insights for the design and optimization of eddy current separators. The underlying mechanism behind the effect of particle size on separation efficiency was discovered by analyzing eddy current and field gradient. The results showed that the magnitude and distribution heterogeneity of eddy current and magnetic field gradient increased with particle size in eddy current separation. Based on this, we further found that increasing the curvature of magnetic field lines within particles could also increase the eddy current force, providing a optimized method to improving the separation efficiency of fine particles. By combining the results of the studies, a more systematic and comprehensive set of optimization guidelines can be proposed for mixtures with different particle size ranges. The separation efficiency of fine particles could be improved by increasing the rotational speed, curvature of magnetic field lines, and electrical conductivity/density of materials, as well as utilizing the eddy current torque. When designing an ECS, the particle size range of the target mixture should be investigated in advance, and the suitable parameters for separating the mixture can be fixed accordingly. In summary, these results can guide the design and optimization of ECS, and also expand the application areas for ECS.

Keywords: eddy current separation, particle size, numerical simulation, metal recovery

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