Search results for: nuclear fuel cycle

Authors: Sahil Patel

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Increasing urbanization leads to a concrete forest. The effects of new development practices occur in the natural hydrologic cycle. Here the concerns have been raised about the groundwater recharge in sufficient quantity. With further development, porous surfaces reduce rapidly. A city like Ahmedabad, with a non-perennial river, is 100% dependent on groundwater. The Ahmedabad city receives its domestic use water from the Narmada river, located about 200 km away. The expenses to bring water is much higher. Ahmedabad city receives annually 800 mm rainfall, and mostly this water increases the local level waterlogging problems; after that, water goes to the Sabarmati river and merges into the sea. The existing developed area of Ahmedabad city is very dense, and does not offer many chances to change the built form and increase porous surfaces to absorb storm-water. Therefore, there is a need to plan upcoming areas with more effective solutions to manage storm-water. This paper is focusing on the management of stormwater for new development by retaining natural hydrology. The Low Impact Development (LID) concept is used to manage storm-water efficiently. Ahmedabad city has a tool called the “Town Planning Scheme,” which helps the local body drive new development by land pooling mechanism. This paper gives a detailed analysis of the selected area (proposed Town Planning Scheme area by the local authority) in Ahmedabad. Here the development control regulations for individual developers and some physical elements for public places are presented to manage storm-water. There is a different solution for the Town Planning scheme than that of the conventional way. A local authority can use it for any area, but it can be site-specific. In the end, there are benefits to locals with some financial analysis and comparisons.

Keywords: water management, green field development, low impact development, town planning scheme

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Authors: Ayodeji Motunrayo Omoare

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Economically fish provides an important source of food and income for both men and women especially many households in the developing world and fishing has an important social and cultural position in river-rine communities. However, fish is highly susceptible to deterioration. Consequently, this study was carried out to correlate income generation of small-scale women fish processors in Abeokuta metropolis, Ogun State, Nigeria. Eighty small-scale women fish processors were randomly selected from five communities as the sample size for this study. Collected data were analyzed using both descriptive and inferential statistics. The results showed that the mean age of the respondents was 31.75 years with average household size of 4 people while 47.5% of the respondents had primary education. Most (86.3%) of the respondents were married and had spent more than 11 years in fish processing. The respondents were predominantly Yoruba tribe (91.2%). Majority (71.3%) of the respondents used traditional kiln for processing their fish while 23.7% of the respondents used hot vegetable oil to fry their fish. Also, the result revealed that respondents sourced capital from Personal Savings (48.8%), Cooperatives (27.5%), Friends and Family (17.5%) and Microfinance Banks (6.2%) for fish processing activities. The respondents generated an average income of ₦7,000.00 from roasted fish, ₦3,500.00 from dried fish, and ₦5,200.00 from fried fish daily. However, inadequate processing equipment (95.0%), non-availability of credit facility from microfinance banks (85.0%), poor electricity supply (77.5%), inadequate extension service support (70.0%), and fuel scarcity (68.7%) were major constraints to fish processing in the study area. Results of chi-square analysis showed that there was a significant relationship between personal characteristics (χ2 = 36.83, df = 9), processing methods (χ2 = 15.88, df = 3) and income generated at p < 0.05 level of significance. It can be concluded that significant relationship existed between processing methods and income generated. The study, therefore, recommends that modern processing equipment should be made available to the respondents at a subsidized price by the agro-allied companies.

Keywords: correlates, income, fish processors, women, small-scale

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Authors: Sara Arafeh, Kovriguine Evguine

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Cytochromes P450 are enzymes that require a supply of electrons to catalyze the synthesis of steroid hormones, fatty acids, and prostaglandin hormone. Cytochrome P450 Oxidoreductase (CYPOR), a membrane bound enzyme, provides these electrons in its open conformation. CYPOR has two cytosolic domains (FAD domain and FMN domain) and an N-terminal in the membrane. In its open conformation, electrons flow from NADPH, FAD, and finally to FMN where cytochrome P450 picks up these electrons. In the closed conformation, cytochrome P450 does not bind to the FMN domain to take the electrons. It was found that when the cytosolic domains are isolated, CYPOR could not bind to cytochrome P450. This suggested that the membrane environment is important for CYPOR function. This project takes the initiative to better understand the dynamics of CYPOR in its full length. Here, we determine the distance between specific sites in the FAD and FMN binding domains in CYPOR by Forster Resonance Energy Transfer (FRET) and Ultrafast TA spectroscopy with and without NADPH. The approach to determine these distances will rely on labeling these sites with red and infrared fluorophores. Mimic membrane attachment is done by inserting CYPOR in lipid nanodiscs. By determining the distances between the donor-acceptor sites in these domains, we can observe the open/closed conformations upon reducing CYPOR in the presence and absence of cytochrome P450. Such study is important to better understand CYPOR mechanism of action in various endosomal membranes including hepatic CYPOR which is vital in plasma cholesterol homeostasis. By investigating the conformational cycles of CYPOR, we can synthesize drugs that would be more efficient in affecting the steroid hormonal levels and metabolism of toxins catalyzed by Cytochrome P450.

Keywords: conformational cycle of CYPOR, cytochrome P450, cytochrome P450 oxidoreductase, FAD domain, FMN domain, FRET, Ultrafast TA Spectroscopy

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Authors: Hung Tran

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This interpretive qualitative study employed three theoretical lenses: Bronfenbrenner’s (1979) Ecological System of Human Development, Vygotsky’s (1978) Sociocultural Theory of Development, and Knowles’s (1970) Adult Learning Theory as the theoretical framework in connection with the constructivist research paradigm to investigate into positive and negative aspects of the extant English as a Foreign Language (EFL) faculty mentoring programs at four higher education institutions (HEIs) in the Mekong River Delta (MRD) of Vietnam. Four apprentice faculty members (mentees), four experienced faculty members (mentors), and two associate deans (administrators) from these HEIs participated in two tape-recorded individual interviews in the Vietnamese language. Twenty interviews were transcribed verbatim and translated into English with verification. The initial analysis of data reveals that the mentoring program, which is mandated by Vietnam’s Ministry of Education and Training, has been implemented differently at these HEIs due to a lack of officially-documented mentoring guidance. Other general themes emerging from the data include essentials of the mentoring program, approaches of the mentoring practice, the mentee – mentor relationship, and lifelong learning beyond the mentoring program. Practically, this study offers stakeholders in the mentoring cycle description of benefits and best practices of tertiary EFL mentorship and a suggested mentoring program that is metaphorically depicted as “a lifebuoy” for its current and potential administrators and mentors to help their mentees survive in the first years of teaching. Theoretically, this study contributes to the world’s growing knowledge of post-secondary mentorship by enriching the modest literature on Asian tertiary EFL mentorship.

Keywords: faculty mentorship, mentees, mentors, administrator, the MRD, Vietnam

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Authors: Ahmed M. Khedr, Saad M. Abdelrahman, Kareem M. Tonbol

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Two geo-referenced sea level datasets (September 2008 – November 2010) and (April 2012 – January 2014) were recorded at Alexandria Western Harbour (AWH). Accurate re-definition of tidal datum, referred to the latest International Terrestrial Reference Frame (ITRF-2014), was discussed and updated to improve our understanding of the old predefined tidal datum at Alexandria. Tidal and non-tidal components of sea level were separated with the use of Delft-3D hydrodynamic model-tide suit (Delft-3D, 2015). Tidal characteristics at AWH were investigated and harmonic analysis showed the most significant 34 constituents with their amplitudes and phases. Tide was identified as semi-diurnal pattern as indicated by a “Form Factor” of 0.24 and 0.25, respectively. Principle tidal datums related to major tidal phenomena were recalculated referred to a meaningful geodetic height datum. The portion of residual energy (surge) out of the total sea level energy was computed for each dataset and found 77% and 72%, respectively. Power spectral density (PSD) showed accurate resolvability in high band (1–6) cycle/days for the nominated independent constituents, except some neighbouring constituents, which are too close in frequency. Wind and atmospheric pressure data, during the recorded sea level time, were analysed and cross-correlated with the surge signals. Moderate association between surge and wind and atmospheric pressure data were obtained. In addition, long-term sea level rise trend at AWH was computed and showed good agreement with earlier estimated rates.

Keywords: Alexandria, Delft-3D, Egypt, geodetic reference, harmonic analysis, sea level

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Authors: Amit Kumar, Rajdeep Chakrabarty, Ganesh Gupta

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This paper illustrates the detailed accreditation process of Accreditation Board of Engineering and Technology (ABET) for accrediting engineering and Technology programs. ABET is a non-governmental agency that accredits engineering and technology, applied and natural sciences, and computing sciences programs. ABET was founded on 10th May 1932 and was founded by Institute of Electrical and Electronics Engineering. International industries accept ABET accredited institutes having the highest standards in their academic programs. In this accreditation, there are eight criteria in general; criterion 1 describes the student outcome evaluations, criteria 2 measures the program's educational objectives, criteria 3 is the student outcome calculated from the marks obtained by students, criteria 4 establishes continuous improvement, criteria 5 focus on curriculum of the institute, criteria 6 is about faculties of this institute, criteria 7 measures the facilities provided by the institute and finally, criteria 8 focus on institutional support towards staff of the institute. In this paper, we focused on the calculative part of each criterion with equations and suitable examples, the files and documentation required for each criterion, and the total workflow of the process. The references and the values used to illustrate the calculations are all taken from the samples provided at ABET's official website. In the final section, we also discuss the criterion-wise score weightage followed by evaluation with timeframe and deadlines.

Keywords: Engineering Accreditation Committee, Computing Accreditation Committee, performance indicator, Program Educational Objective, ABET Criterion 1 to 7, IEEE, National Board of Accreditation, MOOCS, Board of Studies, stakeholders, course objective, program outcome, articulation, attainment, CO-PO mapping, CO-PO-SO mapping, PDCA cycle, degree certificates, course files, course catalogue

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Authors: H. El-Messiry, M. El-Zainy, D. Ghazy

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Diabetes is a metabolic disease that results in a variety of oral health complications. Green tea is a natural antioxidant proved to have powerful effects against diabetes. The aim of this study was to compare between the effect of insulin and green tea on the Parotid gland of streptozotocin induced diabetic Albino rats by using light and transmission electron microscopy. Forty male Albino rats were divided into control group and diabetic groups. The diabetic group received a single injection of 40 mg/kg of streptozotocin intra-peritoneal under anesthesia and was further subdivided into three subgroups: The diabetic untreated subgroup which was untreated for two weeks, the insulin treated subgroup which has received insulin subcutaneously in a daily dose of 5 IU/kg body weight/day for two weeks and a green tea treated subgroup received a daily dose of 1 ml/ 100 gm body weight intragastrically for two weeks. Rats were terminated and parotid glands were dissected and processed for light and transmission electron microscopic examination. Histological examination of the diabetic untreated subgroup revealed acinar cells with pyknotic and hyperchromatic nuclei with cytoplasmic vacuolations. Ultrastructurally, acinar cells showed nuclear pleomorphism, dilated rough endoplasmic reticulum and swollen mitochondria with damaged cristae. Inflammatory cell infiltration was detected both histologically and ultrastructurally. Ducts showed signs of degeneration with loss of their normal outline and stagnated secretion within the lumen. However, insulin and green tea treated subgroups showed minimal degenerative damage and were almost similar to the control with minimal changes. Treatment of the parotid gland of the streptozotocin induced diabetic rats with GT was closely comparable to the traditional insulin therapy in reducing signs of histological and ultrastructural damage.

Keywords: diabetes, green tea, insulin, parotid

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Authors: Damilola Mofikoya

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Developed countries account for a large proportion of greenhouse gas emissions. In the last decade, countries including the United States and China have made a commitment to cut down carbon emissions by signing the Paris Climate Agreement. However, carbon neutrality is a challenging issue to tackle at the country level because of the scale of the problem. To overcome this challenge, cities are at the forefront of these efforts. Many cities in the United States are taking strategic actions and proposing programs and initiatives focused on renewable energy, green transportation, less use of fossil fuel vehicles, etc. There have been concerns about the implications of those strategies and a lack of community engagement. This paper is focused on community-based efforts that help actualize the reduction of carbon footprint through sustained and inclusive action. Existing zero-carbon assessment tools are examined to understand variables and indicators associated with the zero-carbon goals. Based on a broad, systematic review of literature on community strategies, and existing zero-carbon assessment tools, a dashboard was developed to help simplify and demystify carbon neutrality goals at a community level. The literature was able to shed light on the key contributing factors responsible for the success of community efforts in carbon neutrality. Stakeholder education is discussed as one of the strategies to help communities take action and generate momentum. The community-based efforts involving individuals and residents, such as reduction of food wastages, shopping preferences, transit mode choices, and healthy diets, play an important role in the context of zero-carbon initiatives. The proposed community-based dashboard will emphasize the importance of sustained, structured, and collective efforts at a communal scale. Finally, the present study discusses the relationship between life expectancy and quality of life and how it affects carbon neutrality in communities.

Keywords: carbon footprint, communities, life expectancy, quality of life

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Authors: M. Feliciano, F. Maia, A. Gonçalves

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Olive oil production sector plays an important role in Portuguese economy. It had a major growth over the last decade, increasing its weight in the overall national exports. International market penetration for Mediterranean traditional products is increasingly more demanding, especially in the Northern European markets, where consumers are looking for more sustainable products. Trying to support this growing demand this study addresses olive oil production under the environmental and eco-efficiency perspectives. The analysis considers two consecutive product life cycle stages: olive trees farming; and olive oil extraction in mills. Addressing olive farming, data collection covered two different organizations: a middle-size farm (~12ha) (F1) and a large-size farm (~100ha) (F2). Results from both farms show that olive collection activities are responsible for the largest amounts of Green House Gases (GHG) emissions. In this activities, estimate for the Carbon Footprint per olive was higher in F2 (188g CO2e/kgolive) than in F1 (148g CO2e/kgolive). Considering olive oil extraction, two different mills were considered: one using a two-phase system (2P) and other with a three-phase system (3P). Results from the study of two mills show that there is a much higher use of water in 3P. Energy intensity (EI) is similar in both mills. When evaluating the GHG generated, two conditions are evaluated: a biomass neutral condition resulting on a carbon footprint higher in 3P (184g CO2e/Lolive oil) than in 2P (92g CO2e/Lolive oil); and a non-neutral biomass condition in which 2P increase its carbon footprint to 273g CO2e/Lolive oil. When addressing the carbon footprint of possible combinations among studied subsystems, results suggest that olive harvesting is the major source for GHG.

Keywords: carbon footprint, environmental indicators, farming subsystem, industrial subsystem, olive oil

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Authors: K. A. Weidenmann, M. Grigo, B. Brylka, P. Elsner, T. Böhlke

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In order to reduce fuel consumption, the weight of automobiles has to be reduced. Fiber reinforced polymers offer the potential to reach this aim because of their high stiffness to weight ratio. Additionally, the use of fiber reinforced polymers in automotive applications has to allow for an economic large-scale production. In this regard, long fiber reinforced thermoplastics made by direct processing offer both mechanical performance and processability in injection moulding and compression moulding. The work presented in this contribution deals with long glass fiber reinforced polypropylene directly processed in compression moulding (D-LFT). For the use in automotive applications both the temperature and the time dependency of the materials properties have to be investigated to fulfill performance requirements during crash or the demands of service temperatures ranging from -40 °C to 80 °C. To consider both the influence of temperature and time, quasistatic tensile tests have been carried out at different temperatures. These tests have been complemented by high speed tensile tests at different strain rates. As expected, the increase in strain rate results in an increase of the elastic modulus which correlates to an increase of the stiffness with decreasing service temperature. The results are in good accordance with results determined by dynamic mechanical analysis within the range of 0.1 to 100 Hz. The experimental results from different testing methods were grouped and interpreted by using different time temperature shift approaches. In this regard, Williams-Landel-Ferry and Arrhenius approach based on kinetics have been used. As the theoretical shift factor follows an arctan function, an empirical approach was also taken into consideration. It could be shown that this approach describes best the time and temperature superposition for glass fiber reinforced polypropylene manufactured by D-LFT processing.

Keywords: composite, dynamic mechanical analysis, long fibre reinforced thermoplastics, mechanical properties, time temperature superposition

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Authors: Nikolaos Katsoulas, Sofia Faliagka, Athanasios Sapounas

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Greenhouse ventilation is an effective way to remove the extra heat from the greenhouse through air exchange between inside and outside when outside air temperature is lower. However, in the Mediterranean areas during summer, most of the day, the outside air temperature reaches values above 25 C; and natural ventilation can not remove the excess heat outside the greenhouse. Shade screens and whitewash are major existing measures used to reduce the greenhouse air temperature during summer by reducing the solar radiation entering the greenhouse. However, the greenhouse air temperature is reduced with a cost in radiation reduction. In addition, due to high air temperature values outside the greenhouse, generally, these systems are not sufficient for extracting the excess energy during sunny summer days and therefore, other cooling methods, such as forced ventilation combined with evaporative cooling, are needed. Evaporative cooling by means of pad and fan or fog systems is a common technique to reduce sensible heat load by increasing the latent heat fraction of dissipated energy. In most of the cases, the greenhouse growers, when all the above systems are available, apply both shading and evaporative cooling. If a movable screen is available, then the screen is usually activated when a certain radiation level is reached. It is not clear whether the shading screens should be used over the growth cycle or only during the most sensitive stages when the crops had a low leaf area and the canopy transpiration rate cannot significantly contribute to the greenhouse cooling. Furthermore, it is not clear which is the optimum radiation level that screen must be activated. This work aims to present the microclimate and cucumber crop physiological response and yield observed in two greenhouse compartments equipped with a pad and fan evaporative cooling system and a thermal/shading screen that is activated at different radiation levels: when the outside solar radiation reaches 700 or 900 W/m2. The greenhouse is located in Velestino, in Central Greece and the measurements are performed during the spring -summer period with the outside air temperature during summer reaching values up to 42C.

Keywords: microclimate, shading, screen, pad and fan, cooling

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Authors: Takahiro Saida, Takahiro Kogiso, Takahiro Maruyama

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The ordered structural carbon (OSC) material is expected to apply to the electrode of secondary batteries, the catalyst supports, and the biomaterials because it shows the low substance-diffusion resistance by its uniform pore size. In general, the OSC material is synthesized using the template material. Changing size and shape of this template provides the pore size of OSC material according to the purpose. Depositing the oxide nanosheets on the polymer sphere template by the layer by layer (LbL) method was reported as one of the preparation methods of OSC material. The LbL method can provide the controlling thickness of structural wall without the surface modification. When the preparation of the uniform carbon sphere prepared by the LbL method which composed of the graphene oxide wall and the polymethyl-methacrylate (PMMA) core, the reduction treatment will be the important object. Since the graphene oxide has poor electron conductivity due to forming a lot of functional groups on the surface, it could be hard to apply to the electrode of secondary batteries and the catalyst support of fuel cells. In this study, the graphene oxide wall of carbon sphere was reduced by the thermal treatment under the vacuum conditions, and its crystalline structure and electronic state were characterized. Scanning electron microscope images of the carbon sphere after the heat treatment at 300ºC showed maintaining sphere shape, but its shape was collapsed with increasing the heating temperature. In this time, the dissolution rate of PMMA core and the reduction rate of graphene oxide were proportionate to heating temperature. In contrast, extending the heating time was conducive to the conservation of the sphere shape. From results of X-ray photoelectron spectroscopy analysis, its electronic state of the surface was indicated mainly sp² carbon. From the above results, we succeeded in the synthesis of the sphere structure composed by the reduction graphene oxide.

Keywords: carbon sphere, graphene oxide, reduction, layer by layer

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Authors: Joseph Lillington, Tom Gout, Mike Harrison, Ian Farnan

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The vitrification of high-level nuclear waste within borosilicate glass and its incorporation within a multi-barrier repository deep underground is widely accepted as the preferred disposal method. However, for this to happen, any safety case will require validation that the initially localized radionuclides will not be considerably released into the near/far-field. Therefore, accurate mechanistic models are necessary to predict glass dissolution, and these should be robust to a variety of incorporated waste species and leaching test conditions, particularly given substantial variations across international waste-streams. Here, machine learning is used to predict glass material properties (viscosity, density) and glass leaching model parameters from large-scale industrial data. A variety of different machine learning algorithms have been compared to assess performance. Density was predicted solely from composition, whereas viscosity additionally considered temperature. To predict suitable glass leaching model parameters, a large simulated dataset was created by coupling MATLAB and the chemical reactive-transport code HYTEC, considering the state-of-the-art GRAAL model (glass reactivity in allowance of the alteration layer). The trained models were then subsequently applied to the large-scale industrial, experimental data to identify potentially appropriate model parameters. Results indicate that ensemble methods can accurately predict viscosity as a function of temperature and composition across all three industrial datasets. Glass density prediction shows reliable learning performance with predictions primarily being within the experimental uncertainty of the test data. Furthermore, machine learning can predict glass dissolution model parameters behavior, demonstrating potential value in GRAAL model development and in assessing suitable model parameters for large-scale industrial glass dissolution data.

Keywords: machine learning, predictive modelling, pattern recognition, radioactive waste glass

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Authors: Y. Vásquez, F. Reyes, P. Oyola, M. Rubio, J. Muñoz, E. Lissi

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In several cities in Chile, there is significant urban pollution, particularly in Santiago and in cities in the south where biomass is used as fuel in heating and cooking in a large proportion of homes. This has generated interest in knowing what factors can be modulated to control the level of pollution. In this project was conditioned and set up a photochemical chamber (14m3) equipped with gas monitors e.g. CO, NOX, O3, others and PM monitors e.g. dustrack, DMPS, Harvard impactors, etc. This volume could be exposed to UVA lamps, producing a spectrum similar to that generated by the sun. In this chamber, PM and gas emissions associated with biomass burning were studied in the presence and absence of radiation. From the comparative analysis of wood stove (eucalyptus globulus) and pellet (radiata pine), it can be concluded that, in the first approximation, 9-nitroanthracene, 4-nitropyrene, levoglucosan, water soluble potassium and CO present characteristics of the tracers. However, some of them show properties that interfere with this possibility. For example, levoglucosan is decomposed by radiation. The 9-nitroanthracene, 4-nitropyrene are emitted and formed under radiation. The 9-nitroanthracene has a vapor pressure that involves a partition involving the gas phase and particulate matter. From this analysis, it can be concluded that K+ is compound that meets the properties known to be tracer. The PM2.5 emission measured in the automatic pellet stove that was used in this thesis project was two orders of magnitude smaller than that registered by the manual wood stove. This has led to encouraging the use of pellet stoves in indoor heating, particularly in south-central Chile. However, it should be considered, while the use of pellet is not without problems, due to pellet stove generate high concentrations of Nitro-HAP's (secondary organic contaminants). In particular, 4-nitropyrene, compound of high toxicity, also primary and secondary particulate matter, associated with pellet burning produce a decrease in the size distribution of the PM, which leads to a depth penetration of the particles and their toxic components in the respiratory system.

Keywords: biomass burning, photochemical chamber, particulate matter, tracers

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Authors: Gul Jan

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It is the first quantitative ethno-botanical analysis and conservation issues of medicinal flora of Alpine and Sub-alpine, Hindikush region of Pakistan. The objective of the study aims to report, compare the uses and highlight the ethno-Botanical significance of medicinal plants for treatment of various diseases. A total of 250 (242 males and 8 females) local informants including 10 Local Traditional Healers were interviewed. Information was collected through semi-structured interviews, analyzed and compared by quantitative ethno-botanical indices such as Jaccard index (JI), Informant Consensus Factor (ICF), use value (UV) and Relative frequency of citation (RFC).Thorough survey indicated that 57 medicinal plants belongs to 43 families were investigated to treat various illnesses. The highest ICF is recorded for digestive system (0.69%), Circolatory system (0.61%), urinary tract system, (0.53%) and respiratory system (0.52%). Used value indicated that, Achillea mellefolium (UV = 0.68), Aconitum violaceum (UV = 0.69), Valeriana jatamansi (UV = 0.63), Berberis lyceum (UV = 0.65) and are exceedingly medicinal plant species used in the region. In comparison, highest similarity index is recorded in these studies with JI 17.72 followed by 16.41. According to DMR output, Pinus williciana ranked first due to multipurpose uses among all species and was found most threatened with higher market value. Unwise used of natural assets pooled with unsuitable harvesting practices have exaggerated pressure on plant species of the research region. The main issues causative to natural variety loss found were over grazing of animals, forest violation, wild animal hunting, fodder, plant collection as medicine, fuel wood, forest fire, and invasive species negatively affect the natural resources. For viable utilization, in situ and ex situ conservation, skillful collecting, and reforestation project may be the resolution. Further wide field management research is required.

Keywords: quantitative analysis, conservations issues, medicinal flora, alpine and sub-alpine, Hindukush region

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Authors: Xuan Zhao, Wen Jiang

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In this study, a web crawler was used to collect POI sample data from 38 districts and counties of Chongqing in 2022, and ArcGIS was combined to coordinate and projection conversion and realize data visualization. Nuclear density analysis and spatial correlation analysis were used to explore the spatial distribution characteristics of elderly care facilities in Chongqing, and K mean cluster analysis was carried out with GeoDa to study the spatial concentration degree of elderly care resources in 38 districts and counties. Finally, the driving force of spatial differentiation of elderly care facilities in various districts and counties of Chongqing is studied by using the method of geographic detector. The results show that: (1) in terms of spatial distribution structure, the distribution of elderly care facilities in Chongqing is unbalanced, showing a distribution pattern of ‘large dispersion and small agglomeration’ and the asymmetric pattern of ‘west dense and east sparse, north dense and south sparse’ is prominent. (2) In terms of the spatial matching between elderly care resources and the elderly population, there is a weak coordination between the input of elderly care resources and the distribution of the elderly population at the county level in Chongqing. (3) The analysis of the results of the geographical detector shows that the single factor influence is mainly the number of elderly population, public financial revenue and district and county GDP. The high single factor influence is mainly caused by the elderly population, public financial income, and district and county GDP. The influence of each influence factor on the spatial distribution of elderly care facilities is not simply superimposed but has a nonlinear enhancement effect or double factor enhancement. It is necessary to strengthen the synergistic effect of two factors and promote the synergistic effect of multiple factors.

Keywords: aging, elderly care facilities, spatial differentiation, geographical detector, driving force analysis, Mountain city

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Authors: Afshin Shahbazi, Hadi Shadi Naghadeh, Ahmad Khodadadi Darban

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In the Magnetically Assisted Chemical Separation (MACS) process, tiny ferromagnetic particles coated with solvent extractant are used to selectively separate radionuclides and hazardous metals from aqueous waste streams. The contaminant-loaded particles are then recovered from the waste solutions using a magnetic field. In the present study, Cyanex272 or C272 (bis (2,4,4-trimethylpentyl) phosphinic acid) coated magnetic particles are being evaluated for the possible application in the extraction of Thorium (IV) from nuclear waste streams. The uptake behaviour of Th(IV) from nitric acid solutions was investigated by batch studies. Adsorption of Thorium (IV) from aqueous solution onto adsorbent was investigated in a batch system. Adsorption isotherm and adsorption kinetic studies of Thorium (IV) onto nanoparticles coated Cyanex272 were carried out in a batch system. The factors influencing Thorium (IV) adsorption were investigated and described in detail, as a function of the parameters such as initial pH value, contact time, adsorbent mass, and initial Thorium (IV) concentration. Magnetically Assisted Chemical Separation (MACS) process adsorbent showed best results for the fast adsorption of Th (IV) from aqueous solution at aqueous phase acidity value of 0.5 molar. In addition, more than 80% of Th (IV) was removed within the first 2 hours, and the time required to achieve the adsorption equilibrium was only 140 minutes. Langmuir and Frendlich adsorption models were used for the mathematical description of the adsorption equilibrium. Equilibrium data agreed very well with the Langmuir model, with a maximum adsorption capacity of 48 mg.g-1. Adsorption kinetics data were tested using pseudo-first-order, pseudo-second-order and intra-particle diffusion models. Kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model, indicating that the chemical adsorption was the rate-limiting step.

Keywords: Thorium (IV) adsorption, MACS process, magnetic nanoparticles, Cyanex272

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Authors: Khemnath Kharel

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Forest itself is a factory as well as product. It supplies tangible and intangible goods and services. It supplies timber, fuel wood, fodder, grass leaf litter as well as non timber edible goods and medicinal and aromatic products additionally provides environmental services. These environmental services are of local, national, or even global importance. In Nepal more than 19 thousands community forests are providing environmental service in less economic benefit than actual efficiency. There is a risk of cost of management of those forest exceeds benefits and forests get converted to open access resources in future. Most of the environmental goods and services don’t have markets which mean no prices at which they are available to the consumers therefore the valuation of these services goods and services establishment of paying mechanism for such services and insure the benefit to community is more relevant in local as well as global scale. There are few examples of carbon trading in domestic level to meet the country wide emission goal. In this contest the study aims to explore the public attitude towards carbon offsetting and their responsibility over service providers. This study helps in promotion of environment service awareness among general people and service provider; community forest. The research helps to unveil the carbon pool scenario in community forest and willingness to pay for carbon offsetting of people who are consuming more energy than general people and emitting relatively more carbon in atmosphere. The study has assessed the carbon pool status in two community forest. In the study in two community forests carbon pools were assessed following the guideline “Forest Carbon Inventory Guideline 2010” prescribed by Ministry of Forest and soil Conservation, Nepal. Final out comes of analysis in intensively managed area of Hokse CF recorded as 103.58 tons C /ha with 6173.30 tons carbon stock. Similarly in Hariyali CF carbon density was recorded 251.72 mg C /ha. The total carbon stock of intensively managed blocks in Hariyali CF is 35839.62 tons carbon.

Keywords: carbon, offsetting, sequestration, valuation

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Authors: Meryem Zarri, Mohame Tahiri, Fouad Amraoui

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In the context of water resources shortage that Morocco is experiencing in recent years, the mobilization of non-conventional resources becomes a necessity. The reuse of treated water and the bioconversion of biological sewage sludge into value-added products is considered an environmentally friendly and economical approach to the management of this significant resource which represent at least 80 % of consumed fresh wate In this work, we compare the quality of treated water and sewage sludge from wastewater treatment plants in the peri-urban Casablanca by analyzing different physicochemical and bacteriological parameters. The choice was made for three wastewater plants installed in different regions and monitored either by LYDEC and Commune of Had Soualem and use different technologies. Recycling of treated water in agriculture and watering of green spaces is dependent on the compliance of the parameters with international standards (WHO, FAO, …etc.) The preliminary tests of the samples taken during the second half of the year 2021 showed that the advanced technologies put in place at the level of the Mediouna and the airport zone stations (membrane reactor and activated sludge, respectively) give water to the output of the stations more respectful of the standards required in terms of physicochemical parameters (pH, Conductivity, Tubidity, COD, BOD5, TNK, and TPK) and bacteriological (fecal germs, Escherichia Coli, streptococci, Helminthes eggs). The parameters relating to the Had Soualem natural lagoon station are generally at the tolerance’s threshold. The results of analyzes relating to the residual sludge collected at the end of the cycle are, on the whole satisfactory despite a fluctuating variability of the bacteriological parameters.

Keywords: urban wastewater treatment plants, purified wastewater, sewage sludge, physicochemical parameters, bacteriological parameters, peri-urban area of ​​casablanca, morocco

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Authors: Palaniraj Rama Raj, Himeesh Kumar, Paul Adler

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Purpose: To investigate the effect of ultrasound energy, expressed as cumulative dissipated energy (CDE), on short and long-term outcomes after uncomplicated cataract surgery by phacoemulsification. Methods: In this single-surgeon, two-center retrospective study, non-glaucomatous participants who underwent uncomplicated cataract surgery were investigated. Best-corrected visual acuity (BCVA) and intraocular pressure (IOP) were measured at 3 separate time points: pre-operative, Day 1 and ≥1 month. Anterior chamber (AC) inflammation and corneal odema (CO) were assessed at 2 separate time points: Pre-operative and Day 1. Short-term changes (Day 1) in BCVA, IOP, AC and CO and long-term changes (≥1 month) in BCVA and IOP were evaluated as a function of CDE using a multivariate multiple linear regression model, adjusting for age, gender, cataract type and grade, preoperative IOP, preoperative BCVA and duration of long-term follow-up. Results: 110 eyes from 97 non-glaucomatous participants were analysed. 60 (54.55%) were female and 50 (45.45%) were male. The mean (±SD) age was 73.40 (±10.96) years. Higher CDE counts were strongly associated with higher grades of sclerotic nuclear cataracts (p <0.001) and posterior subcapsular cataracts (p <0.036). There was no significant association between CDE counts and cortical cataracts. CDE counts also had a positive correlation with Day 1 CO (p <0.001). There was no correlation between CDE counts and Day 1 AC inflammation. Short-term and long-term changes in post-operative IOP did not demonstrate significant associations with CDE counts (all p >0.05). Though there was no significant correlation between CDE counts and short-term changes in BCVA, higher CDE counts were strongly associated with greater improvements in long-term BCVA (p = 0.011). Conclusion: Though higher CDE counts were strongly associated with higher grades of Day 1 postoperative CO, there appeared to be no detriment to long-term BCVA. Correspondingly, the strong positive correlation between CDE counts and long-term BCVA was likely reflective of the greater severity of underlying cataract type and grade. CDE counts were not associated with short-term or long-term postoperative changes in IOP.

Keywords: cataract surgery, phacoemulsification, cumulative dissipated energy, CDE, surgical outcomes

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Authors: Javier De La Torre Costa, Belen Rubio Ballester, Martina Maier, Paul F. M. J. Verschure

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After a stroke, a great number of patients experience persistent motor impairments such as hemiparesis or weakness in one entire side of the body. As a result, the lack of use of the paretic limb might be one of the main contributors to functional loss after clinical discharge. We aim to reverse this cycle by promoting the use of the paretic limb during activities of daily living (ADLs). To do so, we describe the key components of a system that is composed of a wearable bracelet (i.e., a smartwatch) and a mobile phone, designed to bring a set of neurorehabilitation principles that promote acquisition, retention and generalization of skills to the home of the patient. A fundamental question is whether the loss in motor function derived from learned–non–use may emerge as a consequence of decision–making processes for motor optimization. Our system is based on well-established rehabilitation strategies that aim to reverse this behaviour by increasing the reward associated with action execution as well as implicitly reducing the expected cost associated with the use of the paretic limb, following the notion of the reinforcement–induced movement therapy (RIMT). Here we validate an accelerometer–based measure of arm use, and its capacity to discriminate different activities that require increasing movement of the arm. We also show how the system can act as a personalized assistant by providing specific goals and adjusting them depending on the performance of the patients. The usability and acceptance of the device as a rehabilitation tool is tested using a battery of self–reported and objective measurements obtained from acute/subacute patients and healthy controls. We believe that an extension of these technologies will allow for the deployment of unsupervised rehabilitation paradigms during and beyond the hospitalization time.

Keywords: stroke, wearables, learned non use, hemiparesis, ADLs

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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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Authors: Sertac Arslan, Sezer Kefeli

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In this paper, firstly supercavitating phenomenon and supercavity shape design parameters are explained and then drag force calculation methods of high speed supercavitating torpedoes are investigated with numerical techniques and verified with empirical studies. In order to reach huge speeds such as 200, 300 knots for underwater vehicles, hydrodynamic hull drag force which is proportional to density of water (ρ) and square of speed should be reduced. Conventional heavy weight torpedoes could reach up to ~50 knots by classic underwater hydrodynamic techniques. However, to exceed 50 knots and reach about 200 knots speeds, hydrodynamic viscous forces must be reduced or eliminated completely. This requirement revives supercavitation phenomena that could be implemented to conventional torpedoes. Supercavitation is the use of cavitation effects to create a gas bubble, allowing the torpedo to move at huge speed through the water by being fully developed cavitation bubble. When the torpedo moves in a cavitation envelope due to cavitator in nose section and solid fuel rocket engine in rear section, this kind of torpedoes could be entitled as Supercavitating Torpedoes. There are two types of cavitation; first one is natural cavitation, and second one is ventilated cavitation. In this study, disk cavitator is modeled with natural cavitation and supercavitation phenomenon parameters are studied. Moreover, drag force calculation is performed for disk shape cavitator with numerical techniques and compared via empirical studies. Drag forces are calculated with computational fluid dynamics methods and different empirical methods. Numerical calculation method is developed by comparing with empirical results. In verification study cavitation number (σ), drag coefficient (CD) and drag force (D), cavity wall velocity (U

Keywords: cavity envelope, CFD, high speed underwater vehicles, supercavitation, supercavity flows

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Authors: Namratha Pai, K. Vasantharaj, K. Haribabu

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Our Team is developing an innovative cost effective biological technique to desulfurize crude oil. ’Sulphur’ is found to be present in crude oil samples from .05% - 13.95% and its elimination by industrial methods is expensive currently. Materials required :- Alicyclobacillus acidoterrestrius, potato dextrose agar, oxygen, Pyragallol and inert gas(nitrogen). Method adapted and proposed:- 1) Growth of bacteria studied, energy needs. 2) Compatibility with crude-oil. 3) Reaction rate of bacteria studied and optimized. 4) Reaction development by computer simulation. 5) Simulated work tested by building the reactor. The method being developed requires the use of bacteria Alicyclobacillus acidoterrestrius - an acidothermophilic heterotrophic, soil dwelling aerobic, Sulfur bacteria. The bacteria are fed to crude oil in a unique manner. Its coated onto potato dextrose agar beads, cultured for 24 hours (growth time coincides with time when it begins reacting) and fed into the reactor. The beads are to be replenished with O2 by passing them through a jacket around the reactor which has O2 supply. The O2 can’t be supplied directly as crude oil is inflammable, hence the process. Beads are made to move around based on the concept of fluidized bed reactor. By controlling the velocity of inert gas pumped , the beads are made to settle down when exhausted of O2. It is recycled through the jacket where O2 is re-fed and beads which were inside the ring substitute the exhausted ones. Crude-oil is maintained between 1 atm-270 M Pa pressure and 45°C treated with tartaric acid (Ph reason for bacteria growth) for optimum output. Bacteria being of oxidising type react with Sulphur in crude-oil and liberate out SO4^2- and no gas. SO4^2- is absorbed into H2O. NaOH is fed once reaction is complete and beads separated. Crude-oil is thus separated of SO4^2-, thereby Sulphur, tartaric acid and other acids which are separated out. Bio-corrosion is taken care of by internal wall painting (phenolepoxy paints). Earlier methods used included use of Pseudomonas and Rhodococcus species. They were found to be inefficient, time and energy consuming and reduce the fuel value as they fed on skeleton.

Keywords: alicyclobacillus acidoterrestrius, potato dextrose agar, fluidized bed reactor principle, reaction time for bacteria, compatibility with crude oil

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Authors: Eric Sitorus, Septian Prahastudhi, Turgod Nainggolan, Erwin Riyanto

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Mining by block or panel caving is a mining method that takes advantage of fractures within an ore body, coupled with gravity, to extract material from a predetermined column of ore. The caving column is weakened from beneath through the use of undercutting, after which the ore breaks up and is extracted from below in a continuous cycle. The nature of this method induces cyclical stresses on the pillars of excavations as stress is built up and released over time, which has a detrimental effect on both the installed ground support and the rock mass itself. Ground support capacity, especially on the production where excavation void ratio is highest, is subjected to heavy loading. Strain above threshold of the elongation of support capacity can yield resulting in damage to excavations. Geotechnical engineers must evaluate not only the remnant capacity of ground support systems but also investigate depth of rock mass yield within pillars, backs and floors. Ground Penetrating Radar (GPR) is a geophysical method that has the ability to evaluate rock mass damage using electromagnetic waves. This paper illustrates a case study from the Grasberg mining complex where non-invasive information on the depth of damage and condition of the remaining rock mass was required. GPR with 100 MHz antenna resolution was used to obtain images of the subsurface to determine rehabilitation requirements prior to recommencing production activities. The GPR surveys were used to calibrate the reflection coefficient response of varying rock mass conditions to known Rock Quality Designation (RQD) parameters observed at the mine. The calibrated GPR survey allowed site engineers to map subsurface conditions and plan rehabilitation accordingly.

Keywords: block caving, ground penetrating radar, reflectivity, RQD

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Authors: Jeaha Yang, Ahmed Khan, Donna L. Rodela, Mohammed A. Qaudeer

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Traditional supply chain silos still exist today due to the difficulty of establishing trust between various partners and technological barriers across industries. Companies lose opportunities and revenue and inadvertently make poor business decisions resulting in further challenges. Blockchain technology can bring a new level of transparency through sharing information with a distributed ledger in a decentralized manner that creates a basis of trust for business. Blockchain is a loosely coupled, hub-style communication network in which trading partners can work indirectly with each other for simpler integration, but they work together through the orchestration of their supply chain operations under a coherent process that is developed jointly. A Blockchain increases efficiencies, lowers costs, and improves interoperability to strengthen and automate the supply chain management process while all partners share the risk. Blockchain ledger is built to track inventory lifecycle for supply chain transparency and keeps a journal of inventory movement for real-time reconciliation. State design patterns are used to capture the life cycle (behavior) of inventory management as a state machine for a common, transparent and coherent process which creates an opportunity for trading partners to become more responsive in terms of changes or improvements in process, reconcile discrepancies, and comply with internal governance and external regulations. It enables end-to-end, inter-company visibility at the unit level for more accurate demand planning with better insight into order fulfillment and replenishment.

Keywords: supply chain management, inventory trace-ability, perpetual inventory system, inventory lifecycle, blockchain, inventory consignment, supply chain transparency, digital thread, demand planning, hyper ledger fabric

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Authors: Oluwafemi Samuel Oyamakin

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The forest in Nigeria is currently estimated to extend to around 9.6 million hectares, but used to expand over central and southern Nigeria decades ago. The forest estate is shrinking due to long-term human exploitation for agricultural development, fuel wood demand, uncontrolled forest harvesting and urbanization, amongst other factors, compounded by population growth in rural areas. Nigeria has lost more than 50% of its forest cover since 1990 and currently less than 10% of the country is forested. The current deforestation rate is estimated at 3.7%, which is one of the highest in the world. Reducing Emissions from Deforestation and forest Degradation plus conservation, sustainable management of forests and enhancement of forest carbon stocks constituted what is referred to as REDD+. This study evaluated some of the existing way of computing carbon stocks using eight indigenous tree species like Mansonia, Shorea, Bombax, Terminalia superba, Khaya grandifolia, Khaya senegalenses, Pines and Gmelina arborea. While these components are the essential elements of REDD+ programme, they can be brought under a broader framework of systems analysis designed to arrive at optimal solutions for future predictions through statistical distribution pattern of carbon sequestrated by various species of tree. Available data on height and diameter of trees in Ibadan were studied and their respective potentials of carbon sequestration level were assessed and subjected to tests so as to determine the best statistical distribution that would describe the carbon sequestration pattern of trees. The result of this study suggests a reasonable statistical distribution for carbons sequestered in simulation studies and hence, allow planners and government in determining resources forecast for sustainable development especially where experiments with real-life systems are infeasible. Sustainable management of forest can then be achieved by projecting future condition of forests under different management regimes thereby supporting conservation and REDD+ programmes in Nigeria.

Keywords: REDD+, carbon, climate change, height and diameter

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Authors: Jung-Il Kang, Jeon Eon Park, Yu-Jin Moon, Young-Seok Ahn, Eun-Sook Yoo, Hee-Kyoung Kang

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This study was conducted to evaluate the effect of Undariopsis peterseniana, a seaweed native to Jeju Island, Korea, on the growth of hair. The dermal papilla cells (DPCs) have known to regulate hair growth cycle and length of hair follicle through interact with epithelial cells. When immortalized vibrissa DPCs were treated with the U. peterseniana extract, the U. peterseniana extract significantly increased the proliferation of DPCs. The effect of U. peterseniana extract on the growth of vibrissa follicles was also examined. U. peterseniana extract significantly increased the hair-fiber lengths of the vibrissa follicles. Hair loss is partly caused by dihydrotestosterone (DHT) binding to androgen receptor in hair follicles, and the inhibition of 5α-reductase activity can prevent hair loss through the decrease of DHT level. The U. peterseniana extract inhibited 5α-reductase activity. Minoxidil, a potent hair-growth agent, can induce proliferation in NIH3T3 fibroblasts by opening KATP channels. We thus examined the proliferative effects of U. peterseniana extract in NIH3T3 fibroblasts. U. peterseniana extract significantly increased the proliferation of NIH3T3 fibroblasts. Tetraethylammonium chloride (TEA), a K+ channel blocker, inhibited U. peterseniana-induced proliferation in NIH3T3 fibroblasts. These results suggest that U. peterseniana could have the potential to treat alopecia through the proliferation of DPCs, the inhibition of 5α-reductase activity and the opening of KATP channels. [Acknowledgement] This research was supported by The Leading Human Resource Training Program of Regional Neo industry through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT and future Planning (2016H1D5A1908786).

Keywords: hair growth, Undariopsis peterseniana, vibrissa follicles, dermal papilla cells, 5α-reductase, KATP channels

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Authors: Beatrice Adeoye

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Background: One of the health challenges developing countries face is air pollution from indoor and outdoor activities. Smoke as a result of cooking, burning wastes and power generators litter the air space on a continual basis due to poverty and governance challenges. The short and long term implications of these actions are enormous and studies have attributed smoke as one of the leading preventable risk factors contributing to global burden of respiratory infections. Design/Methods: The issue at hand therefore includes an exploration of the existing policy frameworks regarding smoke, adherence to international conventions and practices, and more importantly the activities of the government in addressing these issues. Aside this, an understanding of the implications of smoke on peoples’ health and well-being also become crucial. Consequently, this article seeks to interrogate the effect of smoke on the health and well-being of Nigerians and the activities of the policy makers in addressing these challenges. Results (Main Argument): This study reviewed both primary and secondary data on poverty, smoke emission and attendant health risks coupled with existing policies on smoke and air pollution in the country. For instance, over 69% of Nigerians are poor, ranking third in the world; 2.9 billion people live in homes using wood, coal or dung as their primary cooking fuel; equally, 50.6% of Nigerians has no access to regular electricity supply. Further, sustainable policy regarding smoke emission is lacking in the country. This work further submitted that continued low standard of living as a result of governance challenges coupled with a lack of sustainable policy have aggravated the health risks related to smoke in the country. Conclusions: The implication on the health of the children, mothers and vulnerable groups for the future of the country is enormous and may continue if not addressed. Urgent attention therefore needs to be focused on this area considering what this portends for the nation now and in the future.

Keywords: air pollution, indoor, outdoor, respiratory infections

Procedia PDF Downloads 329

Authors: Adam Y. Sulaiman, Donal F. Cotter, Ming J. Huang, Neil J. Hewitt

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Suitable low global warming potential (GWP) refrigerants that conform to F-gas regulations are required to extend the operational envelope of high-temperature heat pumps (HTHPs) used for industrial waste heat recovery processes. The thermophysical properties and characteristics of these working fluids need to be assessed to provide a comprehensive understanding of operational effectiveness in HTHP applications. This paper presents the results of a theoretical simulation to investigate a range of low-GWP refrigerants and their suitability to supersede refrigerants HFC-245fa and HFC-365mfc. A steady-state thermodynamic model of a single-stage HTHP with an internal heat exchanger (IHX) was developed to assess system cycle characteristics at temperature ranges between 50 to 80 °C heat source and 90 to 150 °C heat sink. A practical approach to maximize the operational efficiency was examined to determine the effects of regulating minimum superheat within the process and subsequent influence on energetic and exergetic efficiencies. A comprehensive map of minimum superheat across the HTHP operating variables were used to assess specific tipping points in performance at 30 and 70 K temperature lifts. Based on initial results, the refrigerants HCFO-1233zd(E) and HFO-1336mzz(Z) were found to be closely aligned matches for refrigerants HFC-245fa and HFC-365mfc. The overall results show effective performance for HCFO-1233zd(E) occurs between 5-7 K minimum superheat, and HFO-1336mzz(Z) between 18-21 K dependant on temperature lift. This work provides a method to optimize refrigerant selection based on operational indicators to maximize overall HTHPs system performance.

Keywords: high-temperature heat pump, minimum superheat, energy & exergy efficiency, low GWP refrigerants

Procedia PDF Downloads 157