Search results for: district health system
1100 Implementation of Maqasid Sharia in Islamic Financial Institution in Indonesia
Authors: Deden Misbahudin Muayyad, Lavlimatria Esya
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Up to the month of June 2015, Indonesia has 12 Islamic Commercial Banks, 22 Islamic Business Unit, 327 offices in 33 provinces. The initial purpose of the establishment of Islamic financial institutions is to achieve and the welfare of the people in this world and in the hereafter. To realize these goals, the Islamic financial institutions in every kind of aspect of product development and in terms of operations should be based on maqashid sharia, namely keeping the faith, keep the soul, keep the sense, maintain the property, keeping the offspring. To see whether Islamic banking grounded in maqasid sharia, the Islamic banking performance measurements based on the principles of maqasid sharia. Banking performance measurement is not only focusing on profit and other financial measures, but put other values of banks reflects the size of the benefit of non-profit in accordance with the bank's objectives. The measurement using the measurement of financial performance called maqasid sharia index. Maqasid syariah index is a model of Islamic banking performance measurement in accordance with the objectives and characteristics of Islamic banking. Maqasid syariah index was developed based on three main factors, namely the education of individuals, the creation of justice, the achievement of well-being, where the three factors were in accordance with the common goal of maqasid sharia is achieving prosperity and avoid evil. Maqasid syariah index shows that maqasid sharia approach can be a strategic alternative approach to describe how good the performance of the banking system and it can be implemented in the comprehensive policy strategy. This study uses a model of performance measurement framework based on maqasid syariah, in addition to financial performance measures that already exist. Methods to develop the idea of a performance measurement framework of Islamic banking by maqasid sharia is the Sekaran method. Operationally, the methods have now able to describe the elements that will be measured by this study. This is done by observing the behavior of the dimensions illustrated through a concept that has been set. These dimensions translate into derivative elements that can be observed and more scalable, so it can establish measurement indices. This research is descriptive quantitative. Techniques are being made to collect data in this paper is by using purposive sampling method, with 12 Islamic Commercial Banks that qualify as research samples. The financial data taken at 12 banks was sourced from the annual financial statements the period 2008 to 2012 with consideration of the database and ease of access to data. The ratio measured in this study only 7 ratio used in determining the performance of Islamic banking, namely: four ratio refers to the sharia objectives related to education. three ratio while again referring to sharia objectives related to the achievement of welfare. While other ratios associated with justice can not be used in this study because of the limited data used. Total overall calculation of performance indicators and performance ratios on each goal for each bank describes the maqasid syariah index.Keywords: Islamic banking, Maslahah, maqashid syariah, maqashid syariah index
Procedia PDF Downloads 2711099 Trauma Scores and Outcome Prediction After Chest Trauma
Authors: Mohamed Abo El Nasr, Mohamed Shoeib, Abdelhamid Abdelkhalik, Amro Serag
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Background: Early assessment of severity of chest trauma, either blunt or penetrating is of critical importance in prediction of patient outcome. Different trauma scoring systems are widely available and are based on anatomical or physiological parameters to expect patient morbidity or mortality. Up till now, there is no ideal, universally accepted trauma score that could be applied in all trauma centers and is suitable for assessment of severity of chest trauma patients. Aim: Our aim was to compare various trauma scoring systems regarding their predictability of morbidity and mortality in chest trauma patients. Patients and Methods: This study was a prospective study including 400 patients with chest trauma who were managed at Tanta University Emergency Hospital, Egypt during a period of 2 years (March 2014 until March 2016). The patients were divided into 2 groups according to the mode of trauma: blunt or penetrating. The collected data included age, sex, hemodynamic status on admission, intrathoracic injuries, and associated extra-thoracic injuries. The patients outcome including mortality, need of thoracotomy, need for ICU admission, need for mechanical ventilation, length of hospital stay and the development of acute respiratory distress syndrome were also recorded. The relevant data were used to calculate the following trauma scores: 1. Anatomical scores including abbreviated injury scale (AIS), Injury severity score (ISS), New injury severity score (NISS) and Chest wall injury scale (CWIS). 2. Physiological scores including revised trauma score (RTS), Acute physiology and chronic health evaluation II (APACHE II) score. 3. Combined score including Trauma and injury severity score (TRISS ) and 4. Chest-Specific score Thoracic trauma severity score (TTSS). All these scores were analyzed statistically to detect their sensitivity, specificity and compared regarding their predictive power of mortality and morbidity in blunt and penetrating chest trauma patients. Results: The incidence of mortality was 3.75% (15/400). Eleven patients (11/230) died in blunt chest trauma group, while (4/170) patients died in penetrating trauma group. The mortality rate increased more than three folds to reach 13% (13/100) in patients with severe chest trauma (ISS of >16). The physiological scores APACHE II and RTS had the highest predictive value for mortality in both blunt and penetrating chest injuries. The physiological score APACHE II followed by the combined score TRISS were more predictive for intensive care admission in penetrating injuries while RTS was more predictive in blunt trauma. Also, RTS had a higher predictive value for expectation of need for mechanical ventilation followed by the combined score TRISS. APACHE II score was more predictive for the need of thoracotomy in penetrating injuries and the Chest-Specific score TTSS was higher in blunt injuries. The anatomical score ISS and TTSS score were more predictive for prolonged hospital stay in penetrating and blunt injuries respectively. Conclusion: Trauma scores including physiological parameters have a higher predictive power for mortality in both blunt and penetrating chest trauma. They are more suitable for assessment of injury severity and prediction of patients outcome.Keywords: chest trauma, trauma scores, blunt injuries, penetrating injuries
Procedia PDF Downloads 4211098 Hydrological-Economic Modeling of Two Hydrographic Basins of the Coast of Peru
Authors: Julio Jesus Salazar, Manuel Andres Jesus De Lama
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There are very few models that serve to analyze the use of water in the socio-economic process. On the supply side, the joint use of groundwater has been considered in addition to the simple limits on the availability of surface water. In addition, we have worked on waterlogging and the effects on water quality (mainly salinity). In this paper, a 'complex' water economy is examined; one in which demands grow differentially not only within but also between sectors, and one in which there are limited opportunities to increase consumptive use. In particular, high-value growth, the growth of the production of irrigated crops of high value within the basins of the case study, together with the rapidly growing urban areas, provides a rich context to examine the general problem of water management at the basin level. At the same time, the long-term aridity of nature has made the eco-environment in the basins located on the coast of Peru very vulnerable, and the exploitation and immediate use of water resources have further deteriorated the situation. The presented methodology is the optimization with embedded simulation. The wide basin simulation of flow and water balances and crop growth are embedded with the optimization of water allocation, reservoir operation, and irrigation scheduling. The modeling framework is developed from a network of river basins that includes multiple nodes of origin (reservoirs, aquifers, water courses, etc.) and multiple demand sites along the river, including places of consumptive use for agricultural, municipal and industrial, and uses of running water on the coast of Peru. The economic benefits associated with water use are evaluated for different demand management instruments, including water rights, based on the production and benefit functions of water use in the urban agricultural and industrial sectors. This work represents a new effort to analyze the use of water at the regional level and to evaluate the modernization of the integrated management of water resources and socio-economic territorial development in Peru. It will also allow the establishment of policies to improve the process of implementation of the integrated management and development of water resources. The input-output analysis is essential to present a theory about the production process, which is based on a particular type of production function. Also, this work presents the Computable General Equilibrium (CGE) version of the economic model for water resource policy analysis, which was specifically designed for analyzing large-scale water management. As to the platform for CGE simulation, GEMPACK, a flexible system for solving CGE models, is used for formulating and solving CGE model through the percentage-change approach. GEMPACK automates the process of translating the model specification into a model solution program.Keywords: water economy, simulation, modeling, integration
Procedia PDF Downloads 1561097 Cotton Fabrics Functionalized with Green and Commercial Ag Nanoparticles
Authors: Laura Gonzalez, Santiago Benavides, Martha Elena Londono, Ana Elisa Casas, Adriana Restrepo-Osorio
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Cotton products are sensitive to microorganisms due to its ability to retain moisture, which might cause change into the coloration, mechanical properties reduction or foul odor generation; consequently, this represents risks to the health of users. Nowadays, have been carried out researches to give antibacterial properties to textiles using different strategies, which included the use of silver nanoparticles (AgNPs). The antibacterial behavior can be affected by laundering process reducing its effectiveness. In the other way, the environmental impact generated for the synthetic antibacterial agents has motivated to seek new and more ecological ways for produce AgNPs. The aims of this work are to determine the antibacterial activity of cotton fabric functionalized with green (G) and commercial (C) AgNPs after twenty washing cycles, also to evaluate morphological and color changes. A plain weave cotton fabric suitable for dyeing and two AgNPs solutions were use. C a commercial product and G produced using an ecological method, both solutions with 0.5 mM concentration were impregnated on cotton fabric without stabilizer, at a liquor to fabric ratio of 1:20 in constant agitation during 30min and then dried at 70 °C by 10 min. After that the samples were subjected to twenty washing cycles using phosphate-free detergent simulated on agitated flask at 150 rpm, then were centrifuged and dried on a tumble. The samples were characterized using Kirby-Bauer test determine antibacterial activity against E. coli y S. aureus microorganisms, the results were registered by photographs establishing the inhibition halo before and after the washing cycles, the tests were conducted in triplicate. Scanning electron microscope (SEM) was used to observe the morphologies of cotton fabric and treated samples. The color changes of cotton fabrics in relation to the untreated samples were obtained by spectrophotometer analysis. The images, reveals the presence of inhibition halo in the samples treated with C and G AgNPs solutions, even after twenty washing cycles, which indicated a good antibacterial activity and washing durability, with a tendency to better results against to S. aureus bacteria. The presence of AgNPs on the surface of cotton fiber and morphological changes were observed through SEM, after and before washing cycles. The own color of the cotton fiber has been significantly altered with both antibacterial solutions. According to the colorimetric results, the samples treated with C lead to yellowing while the samples modified with G to red yellowing Cotton fabrics treated AgNPs C and G from 0.5 mM solutions exhibited excellent antimicrobial activity against E. coli and S. aureus with good laundering durability effects. The surface of the cotton fibers was modified with the presence of AgNPs C and G due to the presence of NPs and its agglomerates. There are significant changes in the natural color of cotton fabric due to deposition of AgNPs C and G which were maintained after laundering process.Keywords: antibacterial property, cotton fabric, fastness to wash, Kirby-Bauer test, silver nanoparticles
Procedia PDF Downloads 2471096 Real-Time Monitoring of Complex Multiphase Behavior in a High Pressure and High Temperature Microfluidic Chip
Authors: Renée M. Ripken, Johannes G. E. Gardeniers, Séverine Le Gac
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Controlling the multiphase behavior of aqueous biomass mixtures is essential when working in the biomass conversion industry. Here, the vapor/liquid equilibria (VLE) of ethylene glycol, glycerol, and xylitol were studied for temperatures between 25 and 200 °C and pressures of 1 to 10 bar. These experiments were performed in a microfluidic platform, which exhibits excellent heat transfer properties so that equilibrium is reached fast. Firstly, the saturated vapor pressure as a function of the temperature and the substrate mole fraction of the substrate was calculated using AspenPlus with a Redlich-Kwong-Soave Boston-Mathias (RKS-BM) model. Secondly, we developed a high-pressure and high-temperature microfluidic set-up for experimental validation. Furthermore, we have studied the multiphase flow pattern that occurs after the saturation temperature was achieved. A glass-silicon microfluidic device containing a 0.4 or 0.2 m long meandering channel with a depth of 250 μm and a width of 250 or 500 μm was fabricated using standard microfabrication techniques. This device was placed in a dedicated chip-holder, which includes a ceramic heater on the silicon side. The temperature was controlled and monitored by three K-type thermocouples: two were located between the heater and the silicon substrate, one to set the temperature and one to measure it, and the third one was placed in a 300 μm wide and 450 μm deep groove on the glass side to determine the heat loss over the silicon. An adjustable back pressure regulator and a pressure meter were added to control and evaluate the pressure during the experiment. Aqueous biomass solutions (10 wt%) were pumped at a flow rate of 10 μL/min using a syringe pump, and the temperature was slowly increased until the theoretical saturation temperature for the pre-set pressure was reached. First and surprisingly, a significant difference was observed between our theoretical saturation temperature and the experimental results. The experimental values were 10’s of degrees higher than the calculated ones and, in some cases, saturation could not be achieved. This discrepancy can be explained in different ways. Firstly, the pressure in the microchannel is locally higher due to both the thermal expansion of the liquid and the Laplace pressure that has to be overcome before a gas bubble can be formed. Secondly, superheating effects are likely to be present. Next, once saturation was reached, the flow pattern of the gas/liquid multiphase system was recorded. In our device, the point of nucleation can be controlled by taking advantage of the pressure drop across the channel and the accurate control of the temperature. Specifically, a higher temperature resulted in nucleation further upstream in the channel. As the void fraction increases downstream, the flow regime changes along the channel from bubbly flow to Taylor flow and later to annular flow. All three flow regimes were observed simultaneously. The findings of this study are key for the development and optimization of a microreactor for hydrogen production from biomass.Keywords: biomass conversion, high pressure and high temperature microfluidics, multiphase, phase diagrams, superheating
Procedia PDF Downloads 2181095 The 4th Critical R: Conceptualising the Development of Resilience as an Addition to the 3 Rs of the Essential Education Curricula
Authors: Akhentoolove Corbin, Leta De Jonge, Charmaine De Jonge
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Introduction: Various writers have promoted the adoption of the 4th R in the education curricula (relationships, respect, reasoning, religion, computing, science, art, conflict management, music) and the 5th R (responsibility). They argue that the traditional 3 Rs are not adequate for the modern environment and the requirements for students to become functional citizens in society. In particular, the developing countries of the anglophone Caribbean (most of which are tiny islands) are susceptible to the dangers and complexities of climate change and global economic volatility. These proposed additions to the 3Rs do have some justification, but this research considers Resilience as even more important and relevant in a world that is faced with the negative prospects of climate change, poverty, discrimination, and economic volatility. It is argued that the foundation for resilient citizens, workers, and workplaces, must be built in the elementary and secondary/middle schools and then through the tertiary level, to achieve an outcome of more resilient students. Government, business, and society require widespread resilience to be capable of ‘bouncing back’ and be more adaptable, transformational, and sustainable. Methodology: The paper utilises a mixed-methods approach incorporating a questionnaire and interviews to determine participants’ opinions on the importance and relevance of resilience in the schools’ curricula and to government, business, and society. The target groups are as follows: educators at all levels, education administrators, members of the business sector, public sector, and 3rd sector. The research specifically targets the anglophone Caribbean developing countries (Barbados, Guyana, Jamaica, Trinidad, St. Lucia, and St Vincent, and the Grenadines). The research utilises SPSS for data analysis. Major Findings: The preliminary findings suggest that the majority of participants support the adoption of resilience as a 4th R in the curricula of the elementary, secondary/middle schools, and tertiary level in the anglophone Caribbean. The final results will allow the researchers to reveal more specific details on any variations among the islands in the sample andto engage in an in-depth discussion of the relevance and importance of resilience as the 4th R. Conclusion: Results seem to suggest that the education system should adopt the 4th R of resilience so that educators working in collaboration with the family and community/village can develop young citizens who are more resilient and capable of manifesting the behaviours and attitudes associated with ‘bouncing back,’ adaptability, transformation, and sustainability. These findings may be useful for education decision-makers and governments in these Caribbean islands, who have the authority and responsibility for the development of education policy, laws, and regulations.Keywords: education, resilient students, adaptable, transformational, resilient citizens, workplaces, government
Procedia PDF Downloads 701094 An Automated Magnetic Dispersive Solid-Phase Extraction Method for Detection of Cocaine in Human Urine
Authors: Feiyu Yang, Chunfang Ni, Rong Wang, Yun Zou, Wenbin Liu, Chenggong Zhang, Fenjin Sun, Chun Wang
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Cocaine is the most frequently used illegal drug globally, with the global annual prevalence of cocaine used ranging from 0.3% to 0.4 % of the adult population aged 15–64 years. Growing consumption trend of abused cocaine and drug crimes are a great concern, therefore urine sample testing has become an important noninvasive sampling whereas cocaine and its metabolites (COCs) are usually present in high concentrations and relatively long detection windows. However, direct analysis of urine samples is not feasible because urine complex medium often causes low sensitivity and selectivity of the determination. On the other hand, presence of low doses of analytes in urine makes an extraction and pretreatment step important before determination. Especially, in gathered taking drug cases, the pretreatment step becomes more tedious and time-consuming. So developing a sensitive, rapid and high-throughput method for detection of COCs in human body is indispensable for law enforcement officers, treatment specialists and health officials. In this work, a new automated magnetic dispersive solid-phase extraction (MDSPE) sampling method followed by high performance liquid chromatography-mass spectrometry (HPLC-MS) was developed for quantitative enrichment of COCs from human urine, using prepared magnetic nanoparticles as absorbants. The nanoparticles were prepared by silanizing magnetic Fe3O4 nanoparticles and modifying them with divinyl benzene and vinyl pyrrolidone, which possesses the ability for specific adsorption of COCs. And this kind of magnetic particle facilitated the pretreatment steps by electromagnetically controlled extraction to achieve full automation. The proposed device significantly improved the sampling preparation efficiency with 32 samples in one batch within 40mins. Optimization of the preparation procedure for the magnetic nanoparticles was explored and the performances of magnetic nanoparticles were characterized by scanning electron microscopy, vibrating sample magnetometer and infrared spectra measurements. Several analytical experimental parameters were studied, including amount of particles, adsorption time, elution solvent, extraction and desorption kinetics, and the verification of the proposed method was accomplished. The limits of detection for the cocaine and cocaine metabolites were 0.09-1.1 ng·mL-1 with recoveries ranging from 75.1 to 105.7%. Compared to traditional sampling method, this method is time-saving and environmentally friendly. It was confirmed that the proposed automated method was a kind of highly effective way for the trace cocaine and cocaine metabolites analyses in human urine.Keywords: automatic magnetic dispersive solid-phase extraction, cocaine detection, magnetic nanoparticles, urine sample testing
Procedia PDF Downloads 2041093 Cloning and Expression a Gene of β-Glucosidase from Penicillium echinulatum in Pichia pastoris
Authors: Amanda Gregorim Fernandes, Lorena Cardoso Cintra, Rosalia Santos Amorim Jesuino, Fabricia Paula De Faria, Marcio José Poças Fonseca
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Bioethanol is one of the most promising biofuels and able to replace fossil fuels and reduce its different environmental impacts and can be generated from various agroindustrial waste. The Brazil is in first place in bioethanol production to be the largest producer of sugarcane. The bagasse sugarcane (SCB) has lignocellulose which is composed of three major components: cellulose, hemicellulose and lignin. Cellulose is a homopolymer of glucose units connected by glycosidic linkages. Among all species of Penicillium, Penicillium echinulatum has been the focus of attention because they produce high quantities of cellulase and the mutant strain 9A02S1 produces higher enzyme levels compared to the wild. Among the cellulases, the cellobiohydrolases enzymes are the main components of the cellulolytic system of fungi, and are also responsible for most of the potential hydrolytic in enzyme cocktails for the industrial processing of plant biomass and several cellobiohydrolases Penicillium had higher specific activity against cellulose compared to CBH I from Trichoderma reesei. This fact makes it an interesting pattern for higher yields in the enzymatic hydrolysis, and also they are important enzymes in the hydrolysis of crystalline regions of cellulose. Therefore, finding new and more active enzymes become necessary. Meanwhile, β-glycosidases act on soluble substrates and are highly dependent on cellobiohydrolases and endoglucanases action to provide the substrate in the hydrolysis of the biomass, but the cellobiohydrolases and endoglucanases are highly dependent β-glucosidases to maintain efficient hydrolysis. Thus, there is a need to understand the structure-function relationships that govern the catalytic activity of cellulolytic enzymes to elucidate its mechanism of action and optimize its potential as industrial biocatalysts. To evaluate the enzyme β-glucosidase of Penicillium echinulatum (PeBGL1) the gene was synthesized from the assembly sequence from a library in induction conditions and then the PeBGL1 gene was cloned in the vector pPICZαA and transformed into P. pastoris GS115. After processing, the producers of PeBGL1 were analyzed for enzyme activity and protein profile where a band of approximately 100 kDa was viewed. It was also carried out the zymogram. In partial characterization it was determined optimum temperature of 50°C and optimum pH of 6,5. In addition, to increase the secreted recombinant PeBGL1 production by Pichia pastoris, three parameters of P. pastoris culture medium were analysed: methanol, nitrogen source concentrations and the inoculum size. A 23 factorial design was effective in achieving the optimum condition. Altogether, these results point to the potential application of this P. echinulatum β-glucosidase in hydrolysis of cellulose for the production of bioethanol.Keywords: bioethanol, biotechnology, beta-glucosidase, penicillium echinulatum
Procedia PDF Downloads 2451092 Anabasine Intoxication and its Relation to Plant Development Stages
Authors: Thaís T. Valério Caetano, João Máximo De Siqueira, Carlos Alexandre Carollo, Arthur Ladeira Macedo, Vanessa C. Stein
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Nicotiana glauca, commonly known as wild tobacco or tobacco bush, belongs to the Solanaceae family. It is native to South America but has become naturalized in various regions, including Australia, California, Africa, and the Mediterranean. N. glauca is listed in the Global Invasive Species Database (GISD) and the Invasive Species Compendium (CABI). It is known for producing pyridine alkaloids, including anabasine, which is highly toxic. Anabasine is predominantly found in the leaves and can cause severe health issues such as neuromuscular blockade, respiratory arrest, and cardiovascular problems when ingested. Mistaken identity with edible plants like spinach has resulted in food poisoning cases in Israel and Brazil. Anabasine, a minor alkaloid constituent of tobacco, may contribute to tobacco addiction by mimicking or enhancing the effects of nicotine. Therefore, it is essential to investigate the production pattern of anabasine and its relationship to the developmental stages of the plant. This study aimed to establish the relationship between the phenological plant age, cultivation place, and the increase in anabasine concentration, which can lead to human intoxication cases. In this study, N. glauca plants were collected from three different rural areas in Brazil for a year to examine leaves at various stages of development. Samples were also obtained from cultivated plants in Marilândia, Minas Gerais, Brazil, as well as from Divinópolis, Minas Gerais, Brazil, and Arraial do Cabo, Rio de Janeiro, Brazil. In vitro cultivated plants on MS medium were included in the study. The collected leaves were dried, powdered, and stored. Alkaloid extraction was performed using a methanol and water mixture, followed by liquid-liquid extraction with chloroform. The anabasine content was determined using HPLC-DAD analysis with nicotine as a standard. The results indicated that anabasine production increases with the plant's development, peaking in adult leaves during the reproduction phase and declining afterward. In vitro, plants showed similar anabasine production to young leaves. The successful adaptation of N. glauca in new environments poses a global problem, and the correlation between anabasine production and the plant's developmental stages has been understudied. The presence of substances produced by the plant can pose a risk to other species, especially when mistaken for edible plants. The findings from this study shed light on the pattern of anabasine production and its association with plant development, contributing to a better understanding of the potential risks associated with N. glauca and the importance of accurate identification.Keywords: nicotiana glauca graham, global invasive species database, alkaloids, toxic
Procedia PDF Downloads 911091 Calculation of Organ Dose for Adult and Pediatric Patients Undergoing Computed Tomography Examinations: A Software Comparison
Authors: Aya Al Masri, Naima Oubenali, Safoin Aktaou, Thibault Julien, Malorie Martin, Fouad Maaloul
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Introduction: The increased number of performed 'Computed Tomography (CT)' examinations raise public concerns regarding associated stochastic risk to patients. In its Publication 102, the ‘International Commission on Radiological Protection (ICRP)’ emphasized the importance of managing patient dose, particularly from repeated or multiple examinations. We developed a Dose Archiving and Communication System that gives multiple dose indexes (organ dose, effective dose, and skin-dose mapping) for patients undergoing radiological imaging exams. The aim of this study is to compare the organ dose values given by our software for patients undergoing CT exams with those of another software named "VirtualDose". Materials and methods: Our software uses Monte Carlo simulations to calculate organ doses for patients undergoing computed tomography examinations. The general calculation principle consists to simulate: (1) the scanner machine with all its technical specifications and associated irradiation cases (kVp, field collimation, mAs, pitch ...) (2) detailed geometric and compositional information of dozens of well identified organs of computational hybrid phantoms that contain the necessary anatomical data. The mass as well as the elemental composition of the tissues and organs that constitute our phantoms correspond to the recommendations of the international organizations (namely the ICRP and the ICRU). Their body dimensions correspond to reference data developed in the United States. Simulated data was verified by clinical measurement. To perform the comparison, 270 adult patients and 150 pediatric patients were used, whose data corresponds to exams carried out in France hospital centers. The comparison dataset of adult patients includes adult males and females for three different scanner machines and three different acquisition protocols (Head, Chest, and Chest-Abdomen-Pelvis). The comparison sample of pediatric patients includes the exams of thirty patients for each of the following age groups: new born, 1-2 years, 3-7 years, 8-12 years, and 13-16 years. The comparison for pediatric patients were performed on the “Head” protocol. The percentage of the dose difference were calculated for organs receiving a significant dose according to the acquisition protocol (80% of the maximal dose). Results: Adult patients: for organs that are completely covered by the scan range, the maximum percentage of dose difference between the two software is 27 %. However, there are three organs situated at the edges of the scan range that show a slightly higher dose difference. Pediatric patients: the percentage of dose difference between the two software does not exceed 30%. These dose differences may be due to the use of two different generations of hybrid phantoms by the two software. Conclusion: This study shows that our software provides a reliable dosimetric information for patients undergoing Computed Tomography exams.Keywords: adult and pediatric patients, computed tomography, organ dose calculation, software comparison
Procedia PDF Downloads 1651090 A Study of Status of Women by Incorporating Literacy and Employment in India and Some Selected States
Authors: Barnali Thakuria, Labananda Choudhury
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Gender equality and women’s empowerment is one of the components of eight Millennium Development Goal (MDG).Literacy and employment are the parameters which reflect the empowerment of women. But in a developing country like India, literacy and working status among the females are not satisfactory. Both literacy and employment technically can be measured by Literate Life Expectancy (LLE) and Working Life Expectancy (WLE).One can also combine both the factors literacy and working to get a better new measure. The proposed indicator can be called literate-working life expectancy (LWLE). LLE gives an average number of years a person lives in a literate state under current mortality and literacy conditions while WLE defined as average number of years a person lives in a working state if current mortality and working condition prevails. Similarly, LWLE gives number of expected years by a person living under both literate and working state. The situation of females cannot be figured out without comparing both the sexes. In the present paper an attempt has been made to estimate LLE and WLE in India along with some selected states from various zones of India namely Assam from the North-East, Gujarat from the West, Kerala from the South, Rajasthan from the North, Uttar Pradesh from the Central and West Bengal from the East respectively for both the sexes based on 2011 census. Furthermore, we have also developed a formula for a new indicator namely Literate-Working Life Expectancy (LWLE) and the proposed index has been applied in India and the selected states mentioned above for both males and females. Data has been extracted from SRS(Sample Registration System) based Abridged Life Table and Census of India. The computation of LLE follows the method developed by Lutz while WLE has followed the method developed by Saw Swee Hock. By combining both the factors literacy and employment, the new indicator LWLE also follows the method like LLE and WLE. Contrasted results have been found in different parts of India. The result shows that LLE at birth is highest(lowest) in the state Kerala(Uttar Pradesh) with 61.66 (39.51) years among the males. A similar situation is also observed among the females with 62.58 years and 25.11 years respectively. But male WLE at birth is highest (lowest) in Rajasthan(Kerala) with 37.11 (32.64) years. Highest female WLE at birth is also observed in Rajasthan with 23.51 years and the lowest is concentrated in Uttar Pradesh with 11.76 years. It is also found that Kerala’s performance is exceptionally good in terms of LWLE at birth while the lowest LWLE at birth prevails in the state Uttar Pradesh among the males. Female LWLE at birth is highest(lowest) in Kerala(Uttar Pradesh) with 19.73(4.77)years. The corresponding value of the index increases as the number of factors involved in the life expectancy decrease. It is found that women are lagging behind in terms of both literacy and employment. Findings of the study will help the planners to take necessary steps to improve the position of women.Keywords: life expectancy, literacy, literate life expectancy, working life expectancy
Procedia PDF Downloads 4211089 UV-Cured Thiol-ene Based Polymeric Phase Change Materials for Thermal Energy Storage
Authors: M. Vezir Kahraman, Emre Basturk
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Energy storage technology offers new ways to meet the demand to obtain efficient and reliable energy storage materials. Thermal energy storage systems provide the potential to acquire energy savings, which in return decrease the environmental impact related to energy usage. For this purpose, phase change materials (PCMs) that work as 'latent heat storage units' which can store or release large amounts of energy are preferred. Phase change materials (PCMs) are being utilized to absorb, collect and discharge thermal energy during the cycle of melting and freezing, converting from one phase to another. Phase Change Materials (PCMs) can generally be arranged into three classes: organic materials, salt hydrates and eutectics. Many kinds of organic and inorganic PCMs and their blends have been examined as latent heat storage materials. PCMs have found different application areas such as solar energy storage and transfer, HVAC (Heating, Ventilating and Air Conditioning) systems, thermal comfort in vehicles, passive cooling, temperature controlled distributions, industrial waste heat recovery, under floor heating systems and modified fabrics in textiles. Ultraviolet (UV)-curing technology has many advantages, which made it applicable in many different fields. Low energy consumption, high speed, room-temperature operation, low processing costs, high chemical stability, and being environmental friendly are some of its main benefits. UV-curing technique has many applications. One of the many advantages of UV-cured PCMs is that they prevent the interior PCMs from leaking. Shape-stabilized PCM is prepared by blending the PCM with a supporting material, usually polymers. In our study, this problem is minimized by coating the fatty alcohols with a photo-cross-linked thiol-ene based polymeric system. Leakage is minimized because photo-cross-linked polymer acts a matrix. The aim of this study is to introduce a novel thiol-ene based shape-stabilized PCM. Photo-crosslinked thiol-ene based polymers containing fatty alcohols were prepared and characterized for the purpose of phase change materials (PCMs). Different types of fatty alcohols were used in order to investigate their properties as shape-stable PCMs. The structure of the PCMs was confirmed by ATR-FTIR techniques. The phase transition behaviors, thermal stability of the prepared photo-crosslinked PCMs were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). This work was supported by Marmara University, Commission of Scientific Research Project.Keywords: differential scanning calorimetry (DSC), Polymeric phase change material, thermal energy storage, UV-curing
Procedia PDF Downloads 2301088 Improved Food Security and Alleviation of Cyanide Intoxication through Commercialization and Utilization of Cassava Starch by Tanzania Industries
Authors: Mariam Mtunguja, Henry Laswai, Yasinta Muzanilla, Joseph Ndunguru
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Starchy tuberous roots of cassava provide food for people but also find application in various industries. Recently there has been the focus of concentrated research efforts to fully exploit its potential as a sustainable multipurpose crop. High starch yield is the important trait for commercial cassava production for the starch industries. Furthermore, cyanide present in cassava root poses a health challenge in the use of cassava for food. Farming communities where cassava is a staple food, prefer bitter (high cyanogenic) varieties as protection from predators and thieves. As a result, food insecure farmers prefer growing bitter cassava. This has led to cyanide intoxication to this farming communities. Cassava farmers can benefit from marketing cassava to starch producers thereby improving their income and food security. This will decrease dependency on cassava as staple food as a result of increased income and be able to afford other food sources. To achieve this, adequate information is required on the right cassava cultivars and appropriate harvesting period so as to maximize cassava production and profitability. This study aimed at identifying suitable cassava cultivars and optimum time of harvest to maximize starch production. Six commonly grown cultivars were identified and planted in a complete random block design and further analysis was done to assess variation in physicochemical characteristics, starch yield and cyanogenic potentials across three environments. The analysis showed that there is a difference in physicochemical characteristics between landraces (p ≤ 0.05), and can be targeted to different industrial applications. Among landraces, dry matter (30-39%), amylose (11-19%), starch (74-80%) and reducing sugars content (1-3%) varied when expressed on a dry weight basis (p ≤ 0.05); however, only one of the six genotypes differed in crystallinity and mean starch granule particle size, while glucan chain distribution and granule morphology were the same. In contrast, the starch functionality features measured: swelling power, solubility, syneresis, and digestibility differed (p ≤ 0.05). This was supported by Partial least square discriminant analysis (PLS-DA), which highlighted the divergence among the cassavas based on starch functionality, permitting suggestions for the targeted uses of these starches in diverse industries. The study also illustrated genotypic difference in starch yield and cyanogenic potential. Among landraces, Kiroba showed potential for maximum starch yield (12.8 t ha-1) followed by Msenene (12.3 t ha-1) and third was Kilusungu (10.2 t ha-1). The cyanide content of cassava landraces was between 15 and 800 ppm across all trial sites. GGE biplot analysis further confirmed that Kiroba was a superior cultivar in terms of starch yield. Kilusungu had the highest cyanide content and average starch yield, therefore it can also be suitable for use in starch production.Keywords: cyanogen, cassava starch, food security, starch yield
Procedia PDF Downloads 2211087 Place Attachment as Basic Condition for Wellbeing and Life Satisfaction in East African Wetland Users
Authors: Sophie-Bo Heinkel, Andrea Rechenburg, Thomas Kistemann
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The current status of wellbeing and life satisfaction of subsistence farmers in a wetland in Uganda and the contributing role of place attachment has been assessed. The aim of this study is to shed light on environmental factors supporting wellbeing in a wetland setting. Furthermore, it has been assessed, how the emotional bonding to the wetland as ‘place’ influences the peoples’ wellbeing and life satisfaction. The results shed light on the human-environment-relationship. A survey was carried out in three communities in urban and rural areas in a wetland basin in Uganda. A sample (n=235) provided information about the attachment to the wetland, the participants’ relation to the place of their residence and their emotional wellbeing. The Wellbeing Index (WHO-5) was assessed as well as the Perceived Stress Scale (PSS-10) and Rosenberg’s Self-Esteem scale (RSE). Furthermore, the Satisfaction With Life Scale (SWLS) was applied as well as the Place Attachment Inventory (PAI), which consists of the two intertwined dimensions of place identity and place dependence. Beside this, binary indicators as ‘feeling save’ and ‘feeling comfortable’ and ‘enjoying to live at the place of residence’ have been assessed. A bivariate correlation analysis revealed a high interconnectivity between all metric scales. Especially, the subscale ‘place identity’ showed significances with all other scales. A cluster analysis revealed three groups, which differed in the perception of place-related indicators and their attachment to the wetland as well as the status of wellbeing. First, a cluster whose majority is dissatisfied with their lives, but mainly had a good status of emotional well-being. This group does not feel attached to the wetland and lives in a town. Comparably less persons of this group feel safe and comfortable at their place of residence. In the second cluster, persons feel highly attached to the wetland and identify with it. This group was characterized by the high number of persons preferring their current place of residence and do not consider moving. All persons feel well and satisfied with their lives. The third group of persons is mainly living in rural areas and feels highly attached to the wetland. They are satisfied with their lives, but only a small minority is in a good emotional state of wellbeing. The emotional attachment to a place influences life satisfaction and, indirectly, the emotional wellbeing. In the present study it could be shown that subsistence farmers are attached to the wetland, as it is the source of their livelihood. While those living in areas with a good infrastructure are less dependent on the wetland and, therefore, less attached to. This feeling also was mirrored in the perception of a place as being safe and comfortable. The identification with a place is crucial for the feeling of being at “home”. Subsistence farmers feel attached to the ecosystem, but they also might be exposed to environmental and social stressors influencing their short-term emotional wellbeing. The provision of place identity is an ecosystem service provided by wetlands, which supports the status of wellbeing in human beings.Keywords: mental health, positive environments, quality of life, wellbeing
Procedia PDF Downloads 4121086 Inpatient Glycemic Management Strategies and Their Association with Clinical Outcomes in Hospitalized SARS-CoV-2 Patients
Authors: Thao Nguyen, Maximiliano Hyon, Sany Rajagukguk, Anna Melkonyan
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Introduction: Type 2 Diabetes is a well-established risk factor for severe SARS-CoV-2 infection. Uncontrolled hyperglycemia in patients with established or newly diagnosed diabetes is associated with poor outcomes, including increased mortality and hospital length of stay. Objectives: Our study aims to compare three different glycemic management strategies and their association with clinical outcomes in patients hospitalized for moderate to severe SARS-CoV-2 infection. Identifying optimal glycemic management strategies will improve the quality of patient care and improve their outcomes. Method: This is a retrospective observational study on patients hospitalized at Adventist Health White Memorial with severe SARS-CoV-2 infection from 11/1/2020 to 02/28/2021. The following inclusion criteria were used: positive SARS-CoV-2 PCR test, age >18 yrs old, diabetes or random glucose >200 mg/dL on admission, oxygen requirement >4L/min, and treatment with glucocorticoids. Our exclusion criteria included: ICU admission within 24 hours, discharge within five days, death within five days, and pregnancy. The patients were divided into three glycemic management groups: Group 1, managed solely by the Primary Team, Group 2, by Pharmacy; and Group 3, by Endocrinologist. Primary outcomes were average glucose on Day 5, change in glucose between Days 3 and 5, and average insulin dose on Day 5 among groups. Secondary outcomes would be upgraded to ICU, inpatient mortality, and hospital length of stay. For statistics, we used IBM® SPSS, version 28, 2022. Results: Most studied patients were Hispanic, older than 60, and obese (BMI >30). It was the first CV-19 surge with the Delta variant in an unvaccinated population. Mortality was markedly high (> 40%) with longer LOS (> 13 days) and a high ICU transfer rate (18%). Most patients had markedly elevated inflammatory markers (CRP, Ferritin, and D-Dimer). These, in combination with glucocorticoids, resulted in severe hyperglycemia that was difficult to control. Average glucose on Day 5 was not significantly different between groups primary vs. pharmacy vs. endocrine (220.5 ± 63.4 vs. 240.9 ± 71.1 vs. 208.6 ± 61.7 ; P = 0.105). Change in glucose from days 3 to 5 was not significantly different between groups but trended towards favoring the endocrinologist group (-26.6±73.6 vs. 3.8±69.5 vs. -32.2±84.1; P= 0.052). TDD insulin was not significantly different between groups but trended towards higher TDD for the endocrinologist group (34.6 ± 26.1 vs. 35.2 ± 26.4 vs. 50.5 ± 50.9; P=0.054). The endocrinologist group used significantly more preprandial insulin compared to other groups (91.7% vs. 39.1% vs. 65.9% ; P < 0.001). The pharmacy used more basal insulin than other groups (95.1% vs. 79.5% vs. 79.2; P = 0.047). There were no differences among groups in the clinical outcomes: LOS, ICU upgrade, or mortality. Multivariate regression analysis controlled for age, sex, BMI, HbA1c level, renal function, liver function, CRP, d-dimer, and ferritin showed no difference in outcomes among groups. Conclusion: Given high-risk factors in our population, despite efforts from the glycemic management teams, it’s unsurprising no differences in clinical outcomes in mortality and length of stay.Keywords: glycemic management, strategies, hospitalized, SARS-CoV-2, outcomes
Procedia PDF Downloads 4491085 Captive Insurance in Hong Kong and Singapore: A Promising Risk Management Solution for Asian Companies
Authors: Jin Sheng
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This paper addresses a promising area of insurance sector to develop in Asia. Captive insurance, which provides risk-mitigation services for its parent company, has great potentials to develop in energy, infrastructure, agriculture, logistics, catastrophe, and alternative risk transfer (ART), and will greatly affect the framework of insurance industry. However, the Asian captive insurance market only takes a small proportion in the global market. The recent supply chain interruption case of Hanjin Shipping indicates the significance of risk management for an Asian company’s sustainability and resilience. China has substantial needs and great potentials to develop captive insurance, on account of the currency volatility, enterprises’ credit risks, and legal and operational risks of the Belt and Road initiative. Up to date, Mainland Chinese enterprises only have four offshore captives incorporated by CNOOC, Sinopec, Lenovo and CGN Power), three onshore captive insurance companies incorporated by CNPC, China Railway, and COSCO, as well as one industrial captive insurance organization - China Ship-owners Mutual Assurance Association. Its captive market grows slowly with one or two captive insurers licensed yearly after September 2011. As an international financial center, Hong Kong has comparative advantages in taxation, professionals, market access and well-established financial infrastructure to develop a functional captive insurance market. For example, Hong Kong’s income tax for an insurance company is 16.5%; while China's income tax for an insurance company is 25% plus business tax of 5%. Furthermore, restrictions on market entry and operations of China’s onshore captives make establishing offshore captives in international or regional captive insurance centers such as Singapore, Hong Kong, and other overseas jurisdictions to become attractive options. Thus, there are abundant business opportunities in this area. Using methodology of comparative studies and case analysis, this paper discusses the incorporation, regulatory issues, taxation and prospect of captive insurance market in Hong Kong, China and Singapore. Hong Kong and Singapore are both international financial centers with prominent advantages in tax concessions, technology, implementation, professional services, and well-functioning legal system. Singapore, as the domicile of 71 active captives, has been the largest captive insurance hub in Asia, as well as an established reinsurance hub. Hong Kong is an emerging captive insurance hub with 5 to 10 newly licensed captives each year, according to the Hong Kong Financial Services Development Council. It is predicted that Hong Kong will become a domicile for 50 captive insurers by 2025. This paper also compares the formation of a captive in Singapore with other jurisdictions such as Bermuda and Vermont.Keywords: Alternative Risk Transfer (ART), captive insurance company, offshore captives, risk management, reinsurance, self-insurance fund
Procedia PDF Downloads 2291084 The Role of the Corporate Social Responsibility in Poverty Reduction
Authors: M. Verde, G. Falzarano
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The paper examines the connection between corporate social responsibility (CSR), capability approach and poverty reduction; in particular, the local employment development (LED) by way of CSR initiatives. The joint action of LED/CSR results in a win-win situation, not only for the enterprises but also for all the stakeholders involved; in this regard, subsidiarity and coordination between national and regional/local authorities are central to a socially-oriented market economy. In the first section, the CSR is analysed on the basis of its social function in the fight against poverty, as a 'capabilities deprivation'. In the central part, the attention is focused on the relationship between CSR and LED; ergo, on the role of the enterprises in fostering capabilities development (the employment). Besides, all the potential solutions are presented, stressing the possible combinations, in the last part. The benchmark is the enterprise as an economic and a social institution: the business should not be combined with profit merely, paying more attention to its sustainable impact and social contribution. In which way could it be possible? The answer is the CSR. The impact of CSR on poverty reduction is still little explored. The companies help to reduce poverty through economic contribution, human rights and social inclusion; hence, the business becomes an 'agent of development' in order to fight against 'inequality'. The starting point is the pyramid of social responsibility, where ethic and philanthropic responsibilities involve programmes and actions aimed at personal development of the individuals, improving human standard of living in all forms, including poverty, when people do not have a choice between different 'life options', ranging from level of education to employment. At this point, CSR comes into play and works on two dimensions: poverty reduction and poverty prevention, by means of a series of initiatives: first of all, job creation and precarious work reduction. Empowerment of the local actors, financial support and combination of top down and bottom up initiatives are some of CSR areas of activity. Several positive effects occur on individual levels of educations, access to capital, individual health status, empowerment of youth and woman, access to social networks and it was observed that these effects depend on the type of CSR strategy. Indeed, CSR programmes should take into account fundamental criteria, such as the transparency, the information about benefits, a coordination unit among institutions and more clear guidelines. In this way, the advantages to the corporate reputation and to the community translate into a better job matching on the labour market, inter alia. It is important to underline that the success depends on the specific measures of the areas in question, by adapting them to the local needs, in light of general principles and index; therefore, the concrete commitment of the all stakeholders involved is decisive in order to achieve the goals. The enterprise would represent a concrete contribution for the pursuit of sustainable development and for the dissemination of a social and well being awareness.Keywords: capability approach, local employment development, poverty, social inclusion
Procedia PDF Downloads 1401083 Mechanism of Veneer Colouring for Production of Multilaminar Veneer from Plantation-Grown Eucalyptus Globulus
Authors: Ngoc Nguyen
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There is large plantation of Eucalyptus globulus established which has been grown to produce pulpwood. This resource is not suitable for the production of decorative products, principally due to low grades of wood and “dull” appearance but many trials have been already undertaken for the production of veneer and veneer-based engineered wood products, such as plywood and laminated veneer lumber (LVL). The manufacture of veneer-based products has been recently identified as an unprecedented opportunity to promote higher value utilisation of plantation resources. However, many uncertainties remain regarding the impacts of inferior wood quality of young plantation trees on product recovery and value, and with respect to optimal processing techniques. Moreover, the quality of veneer and veneer-based products is far from optimal as trees are young and have small diameters; and the veneers have the significant colour variation which affects to the added value of final products. Developing production methods which would enhance appearance of low-quality veneer would provide a great potential for the production of high-value wood products such as furniture, joinery, flooring and other appearance products. One of the methods of enhancing appearance of low quality veneer, developed in Italy, involves the production of multilaminar veneer, also named “reconstructed veneer”. An important stage of the multilaminar production is colouring the veneer which can be achieved by dyeing veneer with dyes of different colours depending on the type of appearance products, their design and market demand. Although veneer dyeing technology has been well advanced in Italy, it has been focused on poplar veneer from plantation which wood is characterized by low density, even colour, small amount of defects and high permeability. Conversely, the majority of plantation eucalypts have medium to high density, have a lot of defects, uneven colour and low permeability. Therefore, detailed study is required to develop dyeing methods suitable for colouring eucalypt veneers. Brown reactive dye is used for veneer colouring process. Veneers from sapwood and heartwood of two moisture content levels are used to conduct colouring experiments: green veneer and veneer dried to 12% MC. Prior to dyeing, all samples are treated. Both soaking (dipping) and vacuum pressure methods are used in the study to compare the results and select most efficient method for veneer dyeing. To date, the results of colour measurements by CIELAB colour system showed significant differences in the colour of the undyed veneers produced from heartwood part. The colour became moderately darker with increasing of Sodium chloride, compared to control samples according to the colour measurements. It is difficult to conclude a suitable dye solution used in the experiments at this stage as the variables such as dye concentration, dyeing temperature or dyeing time have not been done. The dye will be used with and without UV absorbent after all trials are completed using optimal parameters in colouring veneers.Keywords: Eucalyptus globulus, veneer colouring/dyeing, multilaminar veneer, reactive dye
Procedia PDF Downloads 3501082 Behavioral and EEG Reactions in Native Turkic-Speaking Inhabitants of Siberia and Siberian Russians during Recognition of Syntactic Errors in Sentences in Native and Foreign Languages
Authors: Tatiana N. Astakhova, Alexander E. Saprygin, Tatyana A. Golovko, Alexander N. Savostyanov, Mikhail S. Vlasov, Natalia V. Borisova, Alexandera G. Karpova, Urana N. Kavai-ool, Elena D. Mokur-ool, Nikolay A. Kolchanov, Lubomir I. Aftanas
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The aim of the study is to compare behaviorally and EEG reactions in Turkic-speaking inhabitants of Siberia (Tuvinians and Yakuts) and Russians during the recognition of syntax errors in native and foreign languages. 63 healthy aboriginals of the Tyva Republic, 29 inhabitants of the Sakha (Yakutia) Republic, and 55 Russians from Novosibirsk participated in the study. All participants completed a linguistic task, in which they had to find a syntax error in the written sentences. Russian participants completed the task in Russian and in English. Tuvinian and Yakut participants completed the task in Russian, English, and Tuvinian or Yakut, respectively. EEG’s were recorded during the solving of tasks. For Russian participants, EEG's were recorded using 128-channels. The electrodes were placed according to the extended International 10-10 system, and the signals were amplified using ‘Neuroscan (USA)’ amplifiers. For Tuvinians and Yakuts EEG's were recorded using 64-channels and amplifiers Brain Products, Germany. In all groups 0.3-100 Hz analog filtering, sampling rate 1000 Hz were used. Response speed and the accuracy of recognition error were used as parameters of behavioral reactions. Event-related potentials (ERP) responses P300 and P600 were used as indicators of brain activity. The accuracy of solving tasks and response speed in Russians were higher for Russian than for English. The P300 amplitudes in Russians were higher for English; the P600 amplitudes in the left temporal cortex were higher for the Russian language. Both Tuvinians and Yakuts have no difference in accuracy of solving tasks in Russian and in their respective national languages (Tuvinian and Yakut). However, the response speed was faster for tasks in Russian than for tasks in their national language. Tuvinians and Yakuts showed bad accuracy in English, but the response speed was higher for English than for Russian and the national languages. With Tuvinians, there were no differences in the P300 and P600 amplitudes and in cortical topology for Russian and Tuvinian, but there was a difference for English. In Yakuts, the P300 and P600 amplitudes and topology of ERP for Russian were the same as Russians had for Russian. In Yakuts, brain reactions during Yakut and English comprehension had no difference and were reflected foreign language comprehension -while the Russian language comprehension was reflected native language comprehension. We found out that the Tuvinians recognized both Russian and Tuvinian as native languages, and English as a foreign language. The Yakuts recognized both English and Yakut as a foreign language, only Russian as a native language. According to the inquirer, both Tuvinians and Yakuts use the national language as a spoken language, whereas they don’t use it for writing. It can well be a reason that Yakuts perceive the Yakut writing language as a foreign language while writing Russian as their native.Keywords: EEG, language comprehension, native and foreign languages, Siberian inhabitants
Procedia PDF Downloads 5341081 Implementation of a PDMS Microdevice for the Improved Purification of Circulating MicroRNAs
Authors: G. C. Santini, C. Potrich, L. Lunelli, L. Vanzetti, S. Marasso, M. Cocuzza, C. Pederzolli
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The relevance of circulating miRNAs as non-invasive biomarkers for several pathologies is nowadays undoubtedly clear, as they have been found to have both diagnostic and prognostic value able to add fundamental information to patients’ clinical picture. The availability of these data, however, relies on a time-consuming process spanning from the sample collection and processing to the data analysis. In light of this, strategies which are able to ease this procedure are in high demand and considerable effort have been made in developing Lab-on-a-chip (LOC) devices able to speed up and standardise the bench work. In this context, a very promising polydimethylsiloxane (PDMS)-based microdevice which integrates the processing of the biological sample, i.e. purification of extracellular miRNAs, and reverse transcription was previously developed in our lab. In this study, we aimed at the improvement of the miRNA extraction performances of this micro device by increasing the ability of its surface to absorb extracellular miRNAs from biological samples. For this purpose, we focused on the modulation of two properties of the material: roughness and charge. PDMS surface roughness was modulated by casting with several templates (terminated with silicon oxide coated by a thin anti-adhesion aluminum layer), followed by a panel of curing conditions. Atomic force microscopy (AFM) was employed to estimate changes at the nanometric scale. To introduce modifications in surface charge we functionalized PDMS with different mixes of positively charged 3-aminopropyltrimethoxysilanes (APTMS) and neutral poly(ethylene glycol) silane (PEG). The surface chemical composition was characterized by X-ray photoelectron spectroscopy (XPS) and the number of exposed primary amines was quantified with the reagent sulfosuccinimidyl-4-o-(4,4-dimethoxytrityl) butyrate (s-SDTB). As our final end point, the adsorption rate of all these different conditions was assessed by fluorescence microscopy by incubating a synthetic fluorescently-labeled miRNA. Our preliminary analysis identified casting on thermally grown silicon oxide, followed by a curing step at 85°C for 1 hour, as the most efficient technique to obtain a PDMS surface roughness in the nanometric scaleable to trap miRNA. In addition, functionalisation with 0.1% APTMS and 0.9% PEG was found to be a necessary step to significantly increase the amount of microRNA adsorbed on the surface, therefore, available for further steps as on-chip reverse transcription. These findings show a substantial improvement in the extraction efficiency of our PDMS microdevice, ultimately leading to an important step forward in the development of an innovative, easy-to-use and integrated system for the direct purification of less abundant circulating microRNAs.Keywords: circulating miRNAs, diagnostics, Lab-on-a-chip, polydimethylsiloxane (PDMS)
Procedia PDF Downloads 3181080 The Affective Motivation of Women Miners in Ghana
Authors: Adesuwa Omorede, Rufai Haruna Kilu
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Affective motivation (motivation that is emotionally laden usually related to affect, passion, emotions, moods) in the workplace stimulates individuals to reinforce, persist and commit to their task, which leads to the individual and organizational performance. This leads individuals to reach goals especially in situations where task are highly challenging and hostile. In such situations, individuals are more disposed to be more creative, innovative and see new opportunities from the loopholes in their workplace. However, when individuals feel displaced and less important, an adverse reaction may suffice which may be detrimental to the organization and its performance. One sector where affective motivation is eminently present and relevant, is the mining industry. Due to its intense work environment; mostly dominated by men and masculinity cultures; and deliberate exclusion of women in this environment which, makes the women working in these environments to feel marginalized. In Ghana, the mining industry is mostly seen as a very physical environment especially underground and mostly considerd as 'no place for a woman'. Despite the fact that these women feel less 'needed' or 'appreciated' in such environments, they still have to juggle between intense work shifts; face violence and other health risks with their families, which put a strain on their affective motivational reaction. Beyond these challenges, however, several mining companies in Ghana today are working towards providing a fair and equal working situation for both men and women miners, by recognizing them as key stakeholders, as well as including them in the stages of mining projects from the planning and designing phase to the evaluation and implementation stage. Drawing from the psychology and gender literature, this study takes a narrative approach to identify and understand the shifting gender dynamics within the mine works in Ghana, occasioning a change in background disposition of miners, which leads to more women taking up mine jobs in the country. In doing so, a qualitative study was conducted using semi-structured interviews from Ghana. Several women working within the mining industries in Ghana shared their experiences and how they felt and still feel in their workplace. In addition, archival documents were gathered to support the findings. The results suggest a change in enrolment regimes in a mining and technology university in Ghana, making room for a more gender equal enrolments in the university. A renowned university that train and feed mine work professional into the industry. The results further acknowledge gender equal and diversity recruitment policies and initiatives among the mining companies of Ghana. This study contributes to the psychology and gender literature by highlighting the hindrances women face in the mining industry as well as highlighting several of their affective reactions towards gender inequality. The study also provides several suggestions for decision makers in the mining industry of what can be done in the future to reduce the gender inequality gap within the industry.Keywords: affective motivation, gender shape shifting, mining industry, women miners
Procedia PDF Downloads 3021079 Spatial Accessibility Analysis of Kabul City Public Transport
Authors: Mohammad Idrees Yusofzai, Hirobata Yasuhiro, Matsuo Kojiro
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Kabul is the capital of Afghanistan. It is the focal point of educational, industrial, etc. of Afghanistan. Additionally, the population of Kabul has grown recently and will increase because of return of refugees and shifting of people from other province to Kabul city. However, this increase in population, the issues of urban congestion and other related problems of urban transportation in Kabul city arises. One of the problems is public transport (large buses) service and needs to be modified and enhanced especially large bus routes that are operating in each zone of the 22 zone of Kabul City. To achieve the above mentioned goal of improving public transport, Spatial Accessibility Analysis is one of the important attributes to assess the effectiveness of transportation system and urban transport policy of a city, because accessibility indicator as an alternative tool to support public policy that aims the reinforcement of sustainable urban space. The case study of this research compares the present model (present bus route) and the modified model of public transport. Furthermore, present model, the bus routes in most of the zones are active, however, with having low frequency and unpublished schedule, and accessibility result is analyzed in four cases, based on the variables of accessibility. Whereas in modified model all zones in Kabul is taken into consideration with having specified origin and high frequency. Indeed the number of frequencies is kept high; however, this number is based on the number of buses Millie Bus Enterprise Authority (MBEA) owns. The same approach of cases is applied in modified model to figure out the best accessibility for the modified model. Indeed, the modified model is having a positive impact in congestion level in Kabul city. Besides, analyses of person trip and trip distribution have been also analyzed because how people move in the study area by each mode of transportation. So, the general aims of this research are to assess the present movement of people, identify zones in need of public transport and assess equity level of accessibility in Kabul city. The framework of methodology used in this research is based on gravity analysis model of accessibility; besides, generalized cost (time) of travel and travel mode is calculated. The main data come from person trip survey, socio-economic characteristics, demographic data by Japan International Cooperation Agency, 2008, study of Kabul city and also from the previous researches on travel pattern and the remaining data regarding present bus line and routes have been from MBEA. In conclusion, this research explores zones where public transport accessibility level is high and where it is low. It was found that both models the downtown area or central zones of Kabul city is having high level accessibility. Besides, the present model is the most unfavorable compared with the modified model based on the accessibility analysis.Keywords: accessibility, bus generalized cost, gravity model, public transportation network
Procedia PDF Downloads 1961078 Anabasine Intoxication and Its Relation to Plant Develoment Stages
Authors: Thaís T. Valério Caetano, Lívia de Carvalho Ferreira, João Máximo De Siqueira, Carlos Alexandre Carollo, Arthur Ladeira Macedo, Vanessa C. Stein
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Nicotiana glauca, commonly known as wild tobacco or tobacco bush, belongs to the Solanaceae family. It is native to South America but has become naturalized in various regions, including Australia, California, Africa, and the Mediterranean. N. glauca is listed in the Global Invasive Species Database (GISD) and the Invasive Species Compendium (CABI). It is known for producing pyridine alkaloids, including anabasine, which is highly toxic. Anabasine is predominantly found in the leaves and can cause severe health issues such as neuromuscular blockade, respiratory arrest, and cardiovascular problems when ingested. Mistaken identity with edible plants like spinach has resulted in food poisoning cases in Israel and Brazil. Anabasine, a minor alkaloid constituent of tobacco, may contribute to tobacco addiction by mimicking or enhancing the effects of nicotine. Therefore, it is essential to investigate the production pattern of anabasine and its relationship to the developmental stages of the plant. This study aimed to establish the relationship between the phenological plant age, cultivation place, and the increase in anabasine concentration, which can lead to human intoxication cases. In this study, N. glauca plants were collected from three different rural areas in Brazil during a year to examine leaves at various stages of development. Samples were also obtained from cultivated plants in Marilândia, Minas Gerais, Brazil, as well as from Divinópolis, Minas Gerais, Brazil, and Arraial do Cabo, Rio de Janeiro, Brazil. In vitro cultivated plants on MS medium were included in the study. The collected leaves were dried, powdered, and stored. Alkaloid extraction was performed using a methanol and water mixture, followed by liquid-liquid extraction with chloroform. The anabasine content was determined using HPLC-DAD analysis with nicotine as a standard. The results indicated that anabasine production increases with the plant's development, peaking in adult leaves during the reproduction phase and declining afterward. In vitro, plants showed similar anabasine production to young leaves. The successful adaptation of N. glauca in new environments poses a global problem, and the correlation between anabasine production and the plant's developmental stages has been understudied. The presence of substances produced by the plant can pose a risk to other species, especially when mistaken for edible plants. The findings from this study shed light on the pattern of anabasine production and its association with plant development, contributing to a better understanding of the potential risks associated with N. glauca and the importance of accurate identification.Keywords: alkaloid production, invasive species, nicotiana glauca, plant phenology
Procedia PDF Downloads 861077 Erosion and Deposition of Terrestrial Soil Supplies Nutrients to Estuaries and Coastal Bays: A Flood Simulation Study of Sediment-Nutrient Flux
Authors: Kaitlyn O'Mara, Michele Burford
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Estuaries and coastal bays can receive large quantities of sediment from surrounding catchments during flooding or high flow periods. Large river systems that feed freshwater into estuaries can flow through several catchments of varying geology. Human modification of catchments for agriculture, industry and urban use can contaminate soils with excess nutrients, trace metals and other pollutants. Land clearing, especially clearing of riparian vegetation, can accelerate erosion, mobilising, transporting and depositing soil particles into rivers, estuaries and coastal bays. In this study, a flood simulation experiment was used to study the flux of nutrients between soil particles and water during this erosion, transport and deposition process. Granite, sedimentary and basalt surface soils (as well as sub-soils of granite and sedimentary) were collected from eroding areas surrounding the Brisbane River, Australia. The <63 µm size fraction of each soil type was tumbled in freshwater for 3 days, to simulation flood erosion and transport, followed by stationary exposure to seawater for 4 weeks, to simulate deposition into estuaries. Filtered water samples were taken at multiple time points throughout the experiment and analysed for water nutrient concentrations. The highest rates of nutrient release occurred during the first hour of exposure to freshwater and seawater, indicating a chemical reaction with seawater that may act to release some nutrient particles that remain bound to the soil during turbulent freshwater transport. Although released at a slower rate than the first hour, all of the surface soil types showed continual ammonia, nitrite and nitrate release over the 4-week seawater exposure, suggesting that these soils may provide ongoing supply of these nutrients to estuarine waters after deposition. Basalt surface soil released the highest concentrations of phosphates and dissolved organic phosphorus. Basalt soils are found in much of the agricultural land surrounding the Brisbane River and contributed largely to the 2011 Brisbane River flood plume deposit in Moreton Bay, suggesting these soils may be a source of phosphate enrichment in the bay. The results of this study suggest that erosion of catchment soils during storm and flood events may be a source of nutrient supply in receiving waterways, both freshwater and marine, and that the amount of nutrient release following these events may be affected by the type of soil deposited. For example, flooding in different catchments of a river system over time may result in different algal and food web responses in receiving estuaries.Keywords: flood, nitrogen, nutrient, phosphorus, sediment, soil
Procedia PDF Downloads 1901076 Smart Architecture and Sustainability in the Built Environment for the Hatay Refugee Camp
Authors: Ali Mohammed Ali Lmbash
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The global refugee crisis points to the vital need for sustainable and resistant solutions to different kinds of problems for displaced persons all over the world. Among the myriads of sustainable concerns, however, there are diverse considerations including energy consumption, waste management, water access, and resiliency of structures. Our research aims to develop distinct ideas for sustainable architecture given the exigent problems in disaster-threatened areas starting with the Hatay Refugee camp in Turkey where the majority of the camp dwellers are Syrian refugees. Commencing community-based participatory research which focuses on the socio-environmental issues of displaced populations, this study will apply two approaches with a specific focus on the Hatay region. The initial experiment uses Richter's predictive model and simulations to forecast earthquake outcomes in refugee campers. The result could be useful in implementing architectural design tactics that enhance structural reliability and ensure the security and safety of shelters through earthquakes. In the second experiment a model is generated which helps us in predicting the quality of the existing water sources and since we understand how greatly water is vital for the well-being of humans, we do it. This research aims to enable camp administrators to employ forward-looking practices while managing water resources and thus minimizing health risks as well as building resilience of the refugees in the Hatay area. On the other side, this research assesses other sustainability problems of Hatay Refugee Camp as well. As energy consumption becomes the major issue, housing developers are required to consider energy-efficient designs as well as feasible integration of renewable energy technologies to minimize the environmental impact and improve the long-term sustainability of housing projects. Waste management is given special attention in this case by imposing recycling initiatives and waste reduction measures to reduce the pace of environmental degradation in the camp's land area. As well, study gives an insight into the social and economic reality of the camp, investigating the contribution of initiatives such as urban agriculture or vocational training to the enhancement of livelihood and community empowerment. In a similar fashion, this study combines the latest research with practical experience in order to contribute to the continuing discussion on sustainable architecture during disaster relief, providing recommendations and info that can be adapted on every scale worldwide. Through collaborative efforts and a dedicated sustainability approach, we can jointly get to the root of the cause and work towards a far more robust and equitable society.Keywords: smart architecture, Hatay Camp, sustainability, machine learning.
Procedia PDF Downloads 581075 Destruction of Colon Cells by Nanocontainers of Ferromagnetic
Authors: Lukasz Szymanski, Zbigniew Kolacinski, Grzegorz Raniszewski, Slawomir Wiak, Lukasz Pietrzak, Dariusz Koza, Karolina Przybylowska-Sygut, Ireneusz Majsterek, Zbigniew Kaminski, Justyna Fraczyk, Malgorzata Walczak, Beata Kolasinska, Adam Bednarek, Joanna Konka
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The aim of this work is to investigate the influence of electromagnetic field from the range of radio frequencies on the desired nanoparticles for cancer therapy. In the article, the development and demonstration of the method and the model device for hyperthermic selective destruction of cancer cells are presented. This method was based on the synthesis and functionalization of carbon nanotubes serving as ferromagnetic material nanocontainers. The methodology of the production carbon - ferromagnetic nanocontainers (FNCs) includes: The synthesis of carbon nanotubes, chemical, and physical characterization, increasing the content of a ferromagnetic material and biochemical functionalization involving the attachment of the key addresses. The ferromagnetic nanocontainers were synthesised in CVD and microwave plasma system. Biochemical functionalization of ferromagnetic nanocontainers is necessary in order to increase the binding selectively with receptors presented on the surface of tumour cells. Multi-step modification procedure was finally used to attach folic acid on the surface of ferromagnetic nanocontainers. Pristine ferromagnetic carbon nanotubes are not suitable for application in medicine and biotechnology. Appropriate functionalization of ferromagnetic carbon nanotubes allows to receiving materials useful in medicine. Finally, a product contains folic acids on the surface of FNCs. The folic acid is a ligand of folate receptors – α which is overexpressed on the surface of epithelial tumours cells. It is expected that folic acids will be recognized and selectively bound by receptors presented on the surface of tumour cells. In our research, FNCs were covalently functionalized in a multi-step procedure. Ferromagnetic carbon nanotubes were oxidated using different oxidative agents. For this purpose, strong acids such as HNO3, or mixture HNO3 and H2SO4 were used. Reactive carbonyl and carboxyl groups were formed on the open sides and at the defects on the sidewalls of FNCs. These groups allow further modification of FNCs as a reaction of amidation, reaction of introduction appropriate linkers which separate solid surface of FNCs and ligand (folic acid). In our studies, amino acid and peptide have been applied as ligands. The last step of chemical modification was reaction-condensation with folic acid. In all reaction as coupling reagents were used derivatives of 1,3,5-triazine. The first trials in the device for hyperthermal RF generator have been done. The frequency of RF generator was in the ranges from 10 to 14Mhz and from 265 to 621kHz. Obtained functionalized nanoparticles enabled to reach the temperature of denaturation tumor cells in given frequencies.Keywords: cancer colon cells, carbon nanotubes, hyperthermia, ligands
Procedia PDF Downloads 3131074 Urban Growth and Its Impact on Natural Environment: A Geospatial Analysis of North Part of the UAE
Authors: Mohamed Bualhamam
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Due to the complex nature of tourism resources of the Northern part of the United Arab Emirates (UAE), the potential of Geographical Information Systems (GIS) and Remote Sensing (RS) in resolving these issues was used. The study was an attempt to use existing GIS data layers to identify sensitive natural environment and archaeological heritage resources that may be threatened by increased urban growth and give some specific recommendations to protect the area. By identifying sensitive natural environment and archaeological heritage resources, public agencies and citizens are in a better position to successfully protect important natural lands and direct growth away from environmentally sensitive areas. The paper concludes that applications of GIS and RS in study of urban growth impact in tourism resources are a strong and effective tool that can aid in tourism planning and decision-making. The study area is one of the fastest growing regions in the country. The increase in population along the region, as well as rapid growth of towns, has increased the threat to natural resources and archeological sites. Satellite remote sensing data have been proven useful in assessing the natural resources and in monitoring the changes. The study used GIS and RS to identify sensitive natural environment and archaeological heritage resources that may be threatened by increased urban growth. The result of GIS analyses shows that the Northern part of the UAE has variety for tourism resources, which can use for future tourism development. Rapid urban development in the form of small towns and different economic activities are showing in different places in the study area. The urban development extended out of old towns and have negative affected of sensitive tourism resources in some areas. Tourism resources for the Northern part of the UAE is a highly complex resources, and thus requires tools that aid in effective decision making to come to terms with the competing economic, social, and environmental demands of sustainable development. The UAE government should prepare a tourism databases and a GIS system, so that planners can be accessed for archaeological heritage information as part of development planning processes. Applications of GIS in urban planning, tourism and recreation planning illustrate that GIS is a strong and effective tool that can aid in tourism planning and decision- making. The power of GIS lies not only in the ability to visualize spatial relationships, but also beyond the space to a holistic view of the world with its many interconnected components and complex relationships. The worst of the damage could have been avoided by recognizing suitable limits and adhering to some simple environmental guidelines and standards will successfully develop tourism in sustainable manner. By identifying sensitive natural environment and archaeological heritage resources of the Northern part of the UAE, public agencies and private citizens are in a better position to successfully protect important natural lands and direct growth away from environmentally sensitive areas.Keywords: GIS, natural environment, UAE, urban growth
Procedia PDF Downloads 2631073 A Conceptual Framework of Integrated Evaluation Methodology for Aquaculture Lakes
Authors: Robby Y. Tallar, Nikodemus L., Yuri S., Jian P. Suen
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Research in the subject of ecological water resources management is full of trivial questions addressed and it seems, today to be one branch of science that can strongly contribute to the study of complexity (physical, biological, ecological, socio-economic, environmental, and other aspects). Existing literature available on different facets of these studies, much of it is technical and targeted for specific users. This study offered the combination all aspects in evaluation methodology for aquaculture lakes with its paradigm refer to hierarchical theory and to the effects of spatial specific arrangement of an object into a space or local area. Therefore, the process in developing a conceptual framework represents the more integrated and related applicable concept from the grounded theory. A design of integrated evaluation methodology for aquaculture lakes is presented. The method is based on the identification of a series of attributes which can be used to describe status of aquaculture lakes using certain indicators from aquaculture water quality index (AWQI), aesthetic aquaculture lake index (AALI) and rapid appraisal for fisheries index (RAPFISH). The preliminary preparation could be accomplished as follows: first, the characterization of study area was undertaken at different spatial scales. Second, an inventory data as a core resource such as city master plan, water quality reports from environmental agency, and related government regulations. Third, ground-checking survey should be completed to validate the on-site condition of study area. In order to design an integrated evaluation methodology for aquaculture lakes, finally we integrated and developed rating scores system which called Integrated Aquaculture Lake Index (IALI).The development of IALI are reflecting a compromise all aspects and it responds the needs of concise information about the current status of aquaculture lakes by the comprehensive approach. IALI was elaborated as a decision aid tool for stakeholders to evaluate the impact and contribution of anthropogenic activities on the aquaculture lake’s environment. The conclusion was while there is no denying the fact that the aquaculture lakes are under great threat from the pressure of the increasing human activities, one must realize that no evaluation methodology for aquaculture lakes can succeed by keeping the pristine condition. The IALI developed in this work can be used as an effective, low-cost evaluation methodology of aquaculture lakes for developing countries. Because IALI emphasizes the simplicity and understandability as it must communicate to decision makers and the experts. Moreover, stakeholders need to be helped to perceive their lakes so that sites can be accepted and valued by local people. For this site of lake development, accessibility and planning designation of the site is of decisive importance: the local people want to know whether the lake condition is safe or whether it can be used.Keywords: aesthetic value, AHP, aquaculture lakes, integrated lakes, RAPFISH
Procedia PDF Downloads 2391072 Triple Case Phantom Tumor of Lungs
Authors: Angelis P. Barlampas
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Introduction: The term phantom lung mass describes the ovoid collection of fluid within the interlobular fissure, which initially creates the impression of a mass. The problem of correct differential diagnosis is great, especially in plain radiography. A case is presented with three nodular pulmonary foci, the shape, location, and density of which, as well as the presence of chronic loculated pleural effusions, suggest the presence of multiple phantom tumors of the lung. Purpose: The aim of this paper is to draw the attention of non-experienced and non-specialized physicians to the existence of benign findings that mimic pathological conditions and vice versa. The careful study of a radiological examination and the comparison with previous exams or further control protect against quick wrong conclusions. Methods: A hospitalized patient underwent a non-contrast CT scan of the chest as part of the general control of her situation. Results: Computed tomography revealed pleural effusions, some of them loculated, increased cardiothoracic index, as well as the presence of three nodular foci, one in the left lung and two in the right with a maximum density of up to 18 Hounsfield units and a mean diameter of approximately five centimeters. Two of them are located in the characteristical anatomical position of the major interlobular fissure. The third one is located in the area of the right lower lobe’s posterior basal part, and it presents the same characteristics as the previous ones and is likely to be a loculated fluid collection, within an auxiliary interlobular fissure or a cyst, in the context of the patient's more general pleural entrapments and loculations. The differential diagnosis of nodular foci based on their imaging characteristics includes the following: a) rare metastatic foci with low density (liposarcoma, mucous tumors of the digestive or genital system, necrotic metastatic foci, metastatic renal cancer, etc.), b) necrotic multiple primary lung tumor locations (squamous epithelial cancer, etc. ), c) hamartomas of the lung, d) fibrotic tumors of the interlobular fissures, e) lipoid pneumonia, f) fluid concentrations within the interlobular fissures, g) lipoma of the lung, h) myelolipomas of the lung. Conclusions: The collection of fluid within the interlobular fissure of the lung can give the false impression of a lung mass, particularly on plain chest radiography. In the case of computed tomography, the ability to measure the density of a lesion, combined with the provided high anatomical details of the location and characteristics of the lesion, can lead relatively easily to the correct diagnosis. In cases of doubt or image artifacts, comparison with previous or subsequent examinations can resolve any disagreements, while in rare cases, intravenous contrast may be necessary.Keywords: phantom mass, chest CT, pleural effusion, cancer
Procedia PDF Downloads 551071 Real-Space Mapping of Surface Trap States in Cigse Nanocrystals Using 4D Electron Microscopy
Authors: Riya Bose, Ashok Bera, Manas R. Parida, Anirudhha Adhikari, Basamat S. Shaheen, Erkki Alarousu, Jingya Sun, Tom Wu, Osman M. Bakr, Omar F. Mohammed
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This work reports visualization of charge carrier dynamics on the surface of copper indium gallium selenide (CIGSe) nanocrystals in real space and time using four-dimensional scanning ultrafast electron microscopy (4D S-UEM) and correlates it with the optoelectronic properties of the nanocrystals. The surface of the nanocrystals plays a key role in controlling their applicability for light emitting and light harvesting purposes. Typically for quaternary systems like CIGSe, which have many desirable attributes to be used for optoelectronic applications, relative abundance of surface trap states acting as non-radiative recombination centre for charge carriers remains as a major bottleneck preventing further advancements and commercial exploitation of these nanocrystals devices. Though ultrafast spectroscopic techniques allow determining the presence of picosecond carrier trapping channels, because of relative larger penetration depth of the laser beam, only information mainly from the bulk of the nanocrystals is obtained. Selective mapping of such ultrafast dynamical processes on the surfaces of nanocrystals remains as a key challenge, so far out of reach of purely optical probing time-resolved laser techniques. In S-UEM, the optical pulse generated from a femtosecond (fs) laser system is used to generate electron packets from the tip of the scanning electron microscope, instead of the continuous electron beam used in the conventional setup. This pulse is synchronized with another optical excitation pulse that initiates carrier dynamics in the sample. The principle of S-UEM is to detect the secondary electrons (SEs) generated in the sample, which is emitted from the first few nanometers of the top surface. Constructed at different time delays between the optical and electron pulses, these SE images give direct and precise information about the carrier dynamics on the surface of the material of interest. In this work, we report selective mapping of surface dynamics in real space and time of CIGSe nanocrystals applying 4D S-UEM. We show that the trap states can be considerably passivated by ZnS shelling of the nanocrystals, and the carrier dynamics can be significantly slowed down. We also compared and discussed the S-UEM kinetics with the carrier dynamics obtained from conventional ultrafast time-resolved techniques. Additionally, a direct effect of the state trap removal can be observed in the enhanced photoresponse of the nanocrystals after shelling. Direct observation of surface dynamics will not only provide a profound understanding of the photo-physical mechanisms on nanocrystals’ surfaces but also enable to unlock their full potential for light emitting and harvesting applications.Keywords: 4D scanning ultrafast microscopy, charge carrier dynamics, nanocrystals, optoelectronics, surface passivation, trap states
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