Search results for: intrinsic rate of population increase
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 21511

Search results for: intrinsic rate of population increase

1141 Use of Cellulosic Fibres in Double Layer Porous Asphalt

Authors: Márcia Afonso, Marisa Dinis-Almeida, Cristina Fael

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Climate change, namely precipitation patterns alteration, has led to extreme conditions such as floods and droughts. In turn, excessive construction has led to the waterproofing of the soil, increasing the surface runoff and decreasing the groundwater recharge capacity. The permeable pavements used in areas with low traffic lead to a decrease in the probability of floods peaks occurrence and the sediments reduction and pollutants transport, ensuring rainwater quality improvement. This study aims to evaluate the porous asphalt performance, developed in the laboratory, with addition of cellulosic fibres. One of the main objectives of cellulosic fibres use is to stop binder drainage, preventing its loss during storage and transport. Comparing to the conventional porous asphalt the cellulosic fibres addition improved the porous asphalt performance. The cellulosic fibres allowed the bitumen content increase, enabling retention and better aggregates coating and, consequently, a greater mixture durability. With this solution, it is intended to develop better practices of resilience and adaptation to the extreme climate changes and respond to the sustainability current demands, through the eco-friendly materials use. The mix design was performed for different size aggregates (with fine aggregates – PA1 and with coarse aggregates – PA2). The percentage influence of the fibres to be used was studied. It was observed that overall, the binder drainage decreases as the cellulose fibres percentage increases. It was found that the PA2 mixture obtained most binder drainage relative to PA1 mixture, irrespective of the fibres percentage used. Subsequently, the performance was evaluated through laboratory tests of indirect tensile stiffness modulus, water sensitivity, permeability and permanent deformation. The stiffness modulus for the two mixtures groups (with and without cellulosic fibres) presented very similar values between them. For the water sensitivity test it was observed that porous asphalt containing more fine aggregates are more susceptible to the water presence than mixtures with coarse aggregates. The porous asphalt with coarse aggregates have more air voids which allow water to pass easily leading to ITSR higher values. In the permeability test was observed that asphalt porous without cellulosic fibres presented had lower permeability than asphalt porous with cellulosic fibres. The resistance to permanent deformation results indicates better behaviour of porous asphalt with cellulosic fibres, verifying a bigger rut depth in porous asphalt without cellulosic fibres. In this study, it was observed that porous asphalt with bitumen higher percentages improve the performance to permanent deformation. This fact was only possible due to the bitumen retention by the cellulosic fibres.

Keywords: binder drainage, cellulosic fibres, permanent deformation, porous asphalt

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1140 Clubhouse: A Minor Rebellion against the Algorithmic Tyranny of the Majority

Authors: Vahid Asadzadeh, Amin Ataee

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Since the advent of social media, there has been a wave of optimism among researchers and civic activists about the influence of virtual networks on the democratization process, which has gradually waned. One of the lesser-known concerns is how to increase the possibility of hearing the voices of different minorities. According to the theory of media logic, the media, using their technological capabilities, act as a structure through which events and ideas are interpreted. Social media, through the use of the learning machine and the use of algorithms, has formed a kind of structure in which the voices of minorities and less popular topics are lost among the commotion of the trends. In fact, the recommended systems and algorithms used in social media are designed to help promote trends and make popular content more popular, and content that belongs to minorities is constantly marginalized. As social networks gradually play a more active role in politics, the possibility of freely participating in the reproduction and reinterpretation of structures in general and political structures in particular (as Laclau‎ and Mouffe had in mind‎) can be considered as criteria to democracy in action. The point is that the media logic of virtual networks is shaped by the rule and even the tyranny of the majority, and this logic does not make it possible to design a self-foundation and self-revolutionary model of democracy. In other words, today's social networks, though seemingly full of variety But they are governed by the logic of homogeneity, and they do not have the possibility of multiplicity as is the case in immanent radical democracies (influenced by Gilles Deleuze). However, with the emergence and increasing popularity of Clubhouse as a new social media, there seems to be a shift in the social media space, and that is the diminishing role of algorithms and systems reconditioners as content delivery interfaces. This has led to the fact that in the Clubhouse, the voices of minorities are better heard, and the diversity of political tendencies manifests itself better. The purpose of this article is to show, first, how social networks serve the elimination of minorities in general, and second, to argue that the media logic of social networks must adapt to new interpretations of democracy that give more space to minorities and human rights. Finally, this article will show how the Clubhouse serves the new interpretations of democracy at least in a minimal way. To achieve the mentioned goals, in this article by a descriptive-analytical method, first, the relation between media logic and postmodern democracy will be inquired. The political economy popularity in social media and its conflict with democracy will be discussed. Finally, it will be explored how the Clubhouse provides a new horizon for the concepts embodied in radical democracy, a horizon that more effectively serves the rights of minorities and human rights in general.

Keywords: algorithmic tyranny, Clubhouse, minority rights, radical democracy, social media

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1139 Simulation of Solar Assisted Absorption Cooling and Electricity Generation along with Thermal Storage

Authors: Faezeh Mosallat, Eric L. Bibeau, Tarek El Mekkawy

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Availability of a wide variety of renewable resources, such as large reserves of hydro, biomass, solar and wind in Canada provides significant potential to improve the sustainability of energy uses. As buildings represent a considerable portion of energy use in Canada, application of distributed solar energy systems for heating and cooling may increase the amount of renewable energy use. Parabolic solar trough systems have seen limited deployments in cold northern climates as they are more suitable for electricity production in southern latitudes. Heat production by concentrating solar rays using parabolic troughs can overcome the poor efficiencies of flat panels and evacuated tubes in cold climates. A numerical dynamic model is developed to simulate an installed parabolic solar trough facility in Winnipeg. The results of the numerical model are validated using the experimental data obtained from this system. The model is developed in Simulink and will be utilized to simulate a tri-generation system for heating, cooling and electricity generation in remote northern communities. The main objective of this simulation is to obtain operational data of solar troughs in cold climates as this is lacking in the literature. In this paper, the validated Simulink model is applied to simulate a solar assisted absorption cooling system along with electricity generation using organic Rankine cycle (ORC) and thermal storage. A control strategy is employed to distribute the heated oil from solar collectors among the above three systems considering the temperature requirements. This modeling provides dynamic performance results using real time minutely meteorological data which are collected at the same location the solar system is installed. This is a big step ahead of the current models by accurately calculating the available solar energy at each time step considering the solar radiation fluctuations due to passing clouds. The solar absorption cooling is modeled to use the generated heat from the solar trough system and provide cooling in summer for a greenhouse which is located next to the solar field. A natural gas water heater provides the required excess heat for the absorption cooling at low or no solar radiation periods. The results of the simulation are presented for a summer month in Winnipeg which includes the amount of generated electric power from ORC and contribution of solar energy in the cooling load provision

Keywords: absorption cooling, parabolic solar trough, remote community, validated model

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1138 Double Liposomes Based Dual Drug Delivery System for Effective Eradication of Helicobacter pylori

Authors: Yuvraj Singh Dangi, Brajesh Kumar Tiwari, Ashok Kumar Jain, Kamta Prasad Namdeo

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The potential use of liposomes as drug carriers by i.v. injection is limited by their low stability in blood stream. Firstly, phospholipid exchange and transfer to lipoproteins, mainly HDL destabilizes and disintegrates liposomes with subsequent loss of content. To avoid the pain associated with injection and to obtain better patient compliance studies concerning various dosage forms, have been developed. Conventional liposomes (unilamellar and multilamellar) have certain drawbacks like low entrapment efficiency, stability and release of drug after single breach in external membrane, have led to the new type of liposomal systems. The challenge has been successfully met in the form of Double Liposomes (DL). DL is a recently developed type of liposome, consisting of smaller liposomes enveloped in lipid bilayers. The outer lipid layer of DL can protect inner liposomes against various enzymes, therefore DL was thought to be more effective than ordinary liposomes. This concept was also supported by in vitro release characteristics i.e. DL formation inhibited the release of drugs encapsulated in inner liposomes. DL consists of several small liposomes encapsulated in large liposomes, i.e., multivesicular vesicles (MVV), therefore, DL should be discriminated from ordinary classification of multilamellar vesicles (MLV), large unilamellar vesicles (LUV), small unilamellar vesicles (SUV). However, for these liposomes, the volume of inner phase is small and loading volume of water-soluble drugs is low. In the present study, the potential of phosphatidylethanolamine (PE) lipid anchored double liposomes (DL) to incorporate two drugs in a single system is exploited as a tool to augment the H. pylori eradication rate. Preparation of DL involves two steps, first formation of primary (inner) liposomes by thin film hydration method containing one drug, then addition of suspension of inner liposomes on thin film of lipid containing the other drug. The success of formation of DL was characterized by optical and transmission electron microscopy. Quantitation of DL-bacterial interaction was evaluated in terms of percent growth inhibition (%GI) on reference strain of H. pylori ATCC 26695. To confirm specific binding efficacy of DL to H. pylori PE surface receptor we performed an agglutination assay. Agglutination in DL treated H. pylori suspension suggested selectivity of DL towards the PE surface receptor of H. pylori. Monotherapy is generally not recommended for treatment of a H. pylori infection due to the danger of development of resistance and unacceptably low eradication rates. Therefore, combination therapy with amoxicillin trihydrate (AMOX) as anti-H. pylori agent and ranitidine bismuth citrate (RBC) as antisecretory agent were selected for the study with an expectation that this dual-drug delivery approach will exert acceptable anti-H. pylori activity.

Keywords: Helicobacter pylorI, amoxicillin trihydrate, Ranitidine Bismuth citrate, phosphatidylethanolamine, multi vesicular systems

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1137 The Impact of CSR Satisfaction on Employee Commitment

Authors: Silke Bustamante, Andrea Pelzeter, Andreas Deckmann, Rudi Ehlscheidt, Franziska Freudenberger

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Many companies increasingly seek to enhance their attractiveness as an employer to bind their employees. At the same time, corporate responsibility for social and ecological issues seems to become a more important part of an attractive employer brand. It enables the company to match the values and expectations of its members, to signal fairness towards them and to increase its brand potential for positive psychological identification on the employees’ side. In the last decade, several empirical studies have focused this relationship, confirming a positive effect of employees’ CSR perception and their affective organizational commitment. The current paper aims to take a slightly different view by analyzing the impact of another factor on commitment: the weighted employee’s satisfaction with the employer CSR. For that purpose, it is assumed that commitment levels are rather a result of the fulfillment or disappointment of expectations. Hence, instead of merely asking how CSR perception affects commitment, a more complex independent variable is taken into account: a weighted satisfaction construct that summarizes two different factors. Therefore, the individual level of commitment contingent on CSR is conceptualized as a function of two psychological processes: (1) the individual significance that an employee ascribes to specific employer attributes and (2) the individual satisfaction based on the fulfillment of expectation that rely on preceding perceptions of employer attributes. The results presented are based on a quantitative survey that was undertaken among employees of the German service sector. Conceptually a five-dimensional CSR construct (ecology, employees, marketplace, society and corporate governance) and a two-dimensional non-CSR construct (company and workplace) were applied to differentiate employer characteristics. (1) Respondents were asked to indicate the importance of different facets of CSR-related and non-CSR-related employer attributes. By means of a conjoint analysis, the relative importance of each employer attribute was calculated from the data. (2) In addition to this, participants stated their level of satisfaction with specific employer attributes. Both indications were merged to individually weighted satisfaction indexes on the seven-dimensional levels of employer characteristics. The affective organizational commitment of employees (dependent variable) was gathered by applying the established 15-items Organizational Commitment Questionnaire (OCQ). The findings related to the relationship between satisfaction and commitment will be presented. Furthermore, the question will be addressed, how important satisfaction with CSR is in relation to the satisfaction with other attributes of the company in the creation of commitment. Practical as well as scientific implications will be discussed especially with reference to previous results that focused on CSR perception as a commitment driver.

Keywords: corporate social responsibility, organizational commitment, employee attitudes/satisfaction, employee expectations, employer brand

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1136 Application of Metaverse Service to Construct Nursing Education Theory and Platform in the Post-pandemic Era

Authors: Chen-Jung Chen, Yi-Chang Chen

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While traditional virtual reality and augmented reality only allow for small movement learning and cannot provide a truly immersive teaching experience to give it the illusion of movement, the new technology of both content creation and immersive interactive simulation of the metaverse can just reach infinite close to the natural teaching situation. However, the mixed reality virtual classroom of metaverse has not yet explored its theory, and it is rarely implemented in the situational simulation teaching of nursing education. Therefore, in the first year, the study will intend to use grounded theory and case study methods and in-depth interviews with nursing education and information experts. Analyze the interview data to investigate the uniqueness of metaverse development. The proposed analysis will lead to alternative theories and methods for the development of nursing education. In the second year, it will plan to integrate the metaverse virtual situation simulation technology into the alternate teaching strategy in the pediatric nursing technology course and explore the nursing students' use of this teaching method as the construction of personal technology and experience. By leveraging the unique features of distinct teaching platforms and developing processes to deliver alternative teaching strategies in a nursing technology teaching environment. The aim is to increase learning achievements without compromising teaching quality and teacher-student relationships in the post-pandemic era. A descriptive and convergent mixed methods design will be employed. Sixty third-grade nursing students will be recruited to participate in the research and complete the pre-test. The students in the experimental group (N=30) agreed to participate in 4 real-time mixed virtual situation simulation courses in self-practice after class and conducted qualitative interviews after each 2 virtual situation courses; the control group (N=30) adopted traditional practice methods of self-learning after class. Both groups of students took a post-test after the course. Data analysis will adopt descriptive statistics, paired t-tests, one-way analysis of variance, and qualitative content analysis. This study addresses key issues in the virtual reality environment for teaching and learning within the metaverse, providing valuable lessons and insights for enhancing the quality of education. The findings of this study are expected to contribute useful information for the future development of digital teaching and learning in nursing and other practice-based disciplines.

Keywords: metaverse, post-pandemic era, online virtual classroom, immersive teaching

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1135 Two-wavelength High-energy Cr:LiCaAlF6 MOPA Laser System for Medical Multispectral Optoacoustic Tomography

Authors: Radik D. Aglyamov, Alexander K. Naumov, Alexey A. Shavelev, Oleg A. Morozov, Arsenij D. Shishkin, Yury P.Brodnikovsky, Alexander A.Karabutov, Alexander A. Oraevsky, Vadim V. Semashko

Abstract:

The development of medical optoacoustic tomography with the using human blood as endogenic contrast agent is constrained by the lack of reliable, easy-to-use and inexpensive sources of high-power pulsed laser radiation in the spectral region of 750-900 nm [1-2]. Currently used titanium-sapphire, alexandrite lasers or optical parametric light oscillators do not provide the required and stable output characteristics, they are structurally complex, and their cost is up to half the price of diagnostic optoacoustic systems. Here we are developing the lasers based on Cr:LiCaAlF6 crystals which are free of abovementioned disadvantages and provides intensive ten’s ns-range tunable laser radiation at specific absorption bands of oxy- (~840 nm) and -deoxyhemoglobin (~757 nm) in the blood. Cr:LiCAF (с=3 at.%) crystals were grown in Kazan Federal University by the vertical directional crystallization (Bridgman technique) in graphite crucibles in a fluorinating atmosphere at argon overpressure (P=1500 hPa) [3]. The laser elements have cylinder shape with the diameter of 8 mm and 90 mm in length. The direction of the optical axis of the crystal was normal to the cylinder generatrix, which provides the π-polarized laser action correspondent to maximal stimulated emission cross-section. The flat working surfaces of the active elements were polished and parallel to each other with an error less than 10”. No any antireflection coating was applied. The Q-switched master oscillator-power amplifiers laser system (MOPA) with the dual-Xenon flashlamp pumping scheme in diffuse-reflectivity close-coupled head were realized. A specially designed laser cavity, consisting of dielectric highly reflective reflectors with a 2 m-curvature radius, a flat output mirror, a polarizer and Q-switch sell, makes it possible to operate sequentially in a circle (50 ns - laser one pulse after another) at wavelengths of 757 and 840 nm. The programmable pumping system from Tomowave Laser LLC (Russia) provided independent to each pulses (up to 250 J at 180 μs) pumping to equalize the laser radiation intensity at these wavelengths. The MOPA laser operates at 10 Hz pulse repetition rate with the output energy up to 210 mJ. Taking into account the limitations associated with physiological movements and other characteristics of patient tissues, the duration of laser pulses and their energy allows molecular and functional high-contrast imaging to depths of 5-6 cm with a spatial resolution of at least 1 mm. Highly likely the further comprehensive design of laser allows improving the output properties and realizing better spatial resolution of medical multispectral optoacoustic tomography systems.

Keywords: medical optoacoustic, endogenic contrast agent, multiwavelength tunable pulse lasers, MOPA laser system

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1134 Strengthening by Assessment: A Case Study of Rail Bridges

Authors: Evangelos G. Ilias, Panagiotis G. Ilias, Vasileios T. Popotas

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The United Kingdom has one of the oldest railway networks in the world dating back to 1825 when the world’s first passenger railway was opened. The network has some 40,000 bridges of various construction types using a wide range of materials including masonry, steel, cast iron, wrought iron, concrete and timber. It is commonly accepted that the successful operation of the network is vital for the economy of the United Kingdom, consequently the cost effective maintenance of the existing infrastructure is a high priority to maintain the operability of the network, prevent deterioration and to extend the life of the assets. Every bridge on the railway network is required to be assessed every eighteen years and a structured approach to assessments is adopted with three main types of progressively more detailed assessments used. These assessment types include Level 0 (standardized spreadsheet assessment tools), Level 1 (analytical hand calculations) and Level 2 (generally finite element analyses). There is a degree of conservatism in the first two types of assessment dictated to some extent by the relevant standards which can lead to some structures not achieving the required load rating. In these situations, a Level 2 Assessment is often carried out using finite element analysis to uncover ‘latent strength’ and improve the load rating. If successful, the more sophisticated analysis can save on costly strengthening or replacement works and avoid disruption to the operational railway. This paper presents the ‘strengthening by assessment’ achieved by Level 2 analyses. The use of more accurate analysis assumptions and the implementation of non-linear modelling and functions (material, geometric and support) to better understand buckling modes and the structural behaviour of historic construction details that are not specifically covered by assessment codes are outlined. Metallic bridges which are susceptible to loss of section size through corrosion have largest scope for improvement by the Level 2 Assessment methodology. Three case studies are presented, demonstrating the effectiveness of the sophisticated Level 2 Assessment methodology using finite element analysis against the conservative approaches employed for Level 0 and Level 1 Assessments. One rail overbridge and two rail underbridges that did not achieve the required load rating by means of a Level 1 Assessment due to the inadequate restraint provided by U-Frame action are examined and the increase in assessed capacity given by the Level 2 Assessment is outlined.

Keywords: assessment, bridges, buckling, finite element analysis, non-linear modelling, strengthening

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1133 Budget Impact Analysis of a Stratified Treatment Cascade for Hepatitis C Direct Acting Antiviral Treatment in an Asian Middle-Income Country through the Use of Compulsory and Voluntary Licensing Options

Authors: Amirah Azzeri, Fatiha H. Shabaruddin, Scott A. McDonald, Rosmawati Mohamed, Maznah Dahlui

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Objective: A scaled-up treatment cascade with direct-acting antiviral (DAA) therapy is necessary to achieve global WHO targets for hepatitis C virus (HCV) elimination in Malaysia. Recently, limited access to Sofosbuvir/Daclatasvir (SOF/DAC) is available through compulsory licensing, with future access to Sofosbuvir/Velpatasvir (SOF/VEL) expected through voluntary licensing due to recent agreements. SOF/VEL has superior clinical outcomes, particularly for cirrhotic stages, but has higher drug acquisition costs compared to SOF/DAC. It has been proposed that a stratified treatment cascade might be the most cost-efficient approach for Malaysia whereby all HCV patients are treated with SOF/DAC except for patients with cirrhosis who are treated with SOF/VEL. This study aimed to conduct a five-year budget impact analysis from the provider perspective of the proposed stratified treatment cascade for HCV treatment in Malaysia. Method: A disease progression model that was developed based on model-predicted HCV epidemiology data in Malaysia was used for the analysis, where all HCV patients in scenario A were treated with SOF/DAC for all disease stages while in scenario B, SOF/DAC was used only for non-cirrhotic patients and SOF/VEL was used for the cirrhotic patients. The model projections estimated the annual numbers of patients in care and the numbers of patients to be initiated on DAA treatment nationally. Healthcare costs associated with DAA therapy and disease stage monitoring was included to estimate the downstream cost implications. For scenario B, the estimated treatment uptake of SOF/VEL for cirrhotic patients were 25%, 50%, 75%, 100% and 100% for 2018, 2019, 2020, 2021 and 2022 respectively. Healthcare costs were estimated based on standard clinical pathways for DAA treatment described in recent guidelines. All costs were reported in US dollars (conversion rate US$1=RM4.09, the price year 2018). Scenario analysis was conducted for 5% and 10% reduction of SOF/VEL acquisition cost anticipated from the competitive market pricing of generic DAA in Malaysia. Results: The stratified treatment cascade with SOF/VEL in Scenario B was found to be cost-saving compared to Scenario A. A substantial portion of the cost reduction was due to the costs associated with DAA therapy which resulted in USD 40 thousand (year 1) to USD 443 thousand (year 5) savings annually, with cumulative savings of USD 1.1 million after 5 years. Cost reductions for disease stage monitoring were seen in year three onwards which resulted in cumulative savings of USD 1.1 thousand. Scenario analysis estimated cumulative savings of USD 1.24 to USD 1.35 million when the acquisition cost of SOF/VEL was reduced. Conclusion: A stratified treatment cascade with SOF/VEL was expected to be cost-saving and can results in a budget impact reduction in overall healthcare expenditure in Malaysia compared to treatment with SOF/DAC. The better clinical efficacy with SOF/VEL is expected to halt patients’ HCV disease progression and may reduce downstream costs of treating advanced disease stages. The findings of this analysis may be useful to inform healthcare policies for HCV treatment in Malaysia.

Keywords: Malaysia, direct acting antiviral, compulsory licensing, voluntary licensing

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1132 Developmental Difficulties Prevalence and Management Capacities among Children Including Genetic Disease in a North Coastal District of Andhra Pradesh, India: A Cross-sectional Study

Authors: Koteswara Rao Pagolu, Raghava Rao Tamanam

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The present study was aimed to find out the prevalence of DD's in Visakhapatnam, one of the north coastal districts of Andhra Pradesh, India during a span of five years. A cross-sectional investigation was held at District early intervention center (DEIC), Visakhapatnam from 2016 to 2020. To identify the pattern and trend of different DD's including seasonal variations, a retrospective analysis of the health center's inpatient database for the past 5 years was done. Male and female children aged 2 months-18 years are included in the study with the prior permission of the concerned medical officer. The screening tool developed by the Ministry of health and family welfare, India, was used for the study. Among 26,423 cases, children with birth defects are 962, 2229 with deficiencies, 7516 with diseases, and 15716 with disabilities were admitted during the study period. From birth defects, congenital deafness occurred in large numbers with 22.66%, and neural tube defect observed in a small number of cases with 0.83% during the period. From the side of deficiencies, severe acute malnutrition has mostly occurred (66.80 %) and a small number of children were affected with goiter (1.70%). Among the diseases, dental carriers (67.97%) are mostly found and these cases were at peak during the years 2016 and 2019. From disabilities, children with vision impairment (20.55%) have mostly approached the center. Over the past 5 years, the admission rate of down's syndrome and congenital deafness cases showed a rising trend up to 2019 and then declined. Hearing impairment, motor delay, and learning disorder showed a steep rise and gradual decline trend, whereas severe anemia, vitamin-D deficiency, otitis media, reactive airway disease, and attention deficit hyperactivity disorder showed a declining trend. However, congenital heart diseases, dental caries, and vision impairment admission rates showed a zigzag pattern over the past 5 years. This center had inadequate diagnostic facilities related to genetic disease management. For advanced confirmation, the cases are referred to a district government hospital or private diagnostic laboratories in the city for genetic tests. Information regarding the overall burden and pattern of admissions in the health center is obtained by the review of DEIC records. Through this study, it is observed that the incidence of birth defects, as well as genetic disease burden, is high in the Visakhapatnam district. Hence there is a need for strengthening of management services for these diseases in this region.

Keywords: child health screening, developmental delays, district early intervention center, genetic disease management, infrastructural facility, Visakhapatnam district

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1131 Reduction of Process of Evidence in Specific Forms of Criminal Proceeding: Problems and Risks

Authors: Filip Ščerba, Veronika Pochylá

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Performing of the acts within criminal proceedings usually takes too long and thus this phenomenon can be regarded as one of the most burning problems which have plagued the criminal justice not only in the Czech Republic but at least all over Europe for the last few decades. This problem obviously has to be dealt with and thus the need to tackle this issue has resulted in the trend which is sometimes called Criminal Justice Rationalization, i.e. introducing and enforcing methods supporting the increase in efficiency of the criminal justice in order to make the criminal proceedings shorter and administrative procedure easier. This resulted in the introduction of institutes such as e.g. diversions in criminal proceedings or other forms of shortened pre-trial proceedings, which may be used primarily for dealing with less serious crimes. But also the institute, which was originally mentioned in connection with the system of criminal law in the countries belonging to the Anglo-Saxon legal order where it is frequently called of plea bargaining, has been introduced into the criminal law of many European countries, and it may be applied also in cases of serious crimes. All these special and shortened forms of criminal proceedings are connected with limited extent of process of evidence; in fact, some of these specific forms of criminal proceedings are designed for the purpose to simplify the process of evidence. That is also the reason, why some of these procedures are conditioned with the defendant’s confession. Main hypothesis: Limited process of evidence represents also a potential conflict with certain fundamental principles upon which the criminal proceeding in the Continental legal system is based. (A conflict with principle of material truth may be considered as the most important problem. This principle states that the bodies in criminal proceedings must clarify the facts of the case beyond reasonable doubt to such extent that a decision can be made; the defendant’s confession does not mean that these bodies are freed from the duty to review all the circumstances and facts of the case. Such principle is typical for criminal law in Central European region.) Basic methodologies: The paper is going to analyze such a problem of weakening of the principle of material truth in modern criminal law. Such analysis will be provided primarily on the base of the Czech criminal law, but also other legal regulations will be taken into consideration, and its result may have some relevance for all legal regulations belonging to the Continental legal system, so the paper offers also a comparison with legal systems of other Central European countries.

Keywords: burden of proof, central European countries, criminal justice rationalization, criminal proceeding, Czech legislation, Czech republic, defendant, diversions, evidence, fundamental principles, plea bargaining, pre-trial proceedings, principle of material truth, process of evidence, process of evidence

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1130 Influence of Sewage Sludge on Agricultural Land Quality and Crop

Authors: Catalina Iticescu, Lucian P. Georgescu, Mihaela Timofti, Gabriel Murariu

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Since the accumulation of large quantities of sewage sludge is producing serious environmental problems, numerous environmental specialists are looking for solutions to solve this problem. The sewage sludge obtained by treatment of municipal wastewater may be used as fertiliser on agricultural soils because such sludge contains large amounts of nitrogen, phosphorus and organic matter. In many countries, sewage sludge is used instead of chemical fertilizers in agriculture, this being the most feasible method to reduce the increasingly larger quantities of sludge. The use of sewage sludge on agricultural soils is allowed only with a strict monitoring of their physical and chemical parameters, because heavy metals exist in varying amounts in sewage sludge. Exceeding maximum permitted quantities of harmful substances may lead to pollution of agricultural soil and may cause their removal aside because the plants may take up the heavy metals existing in soil and these metals will most probably be found in humans and animals through food. The sewage sludge analyzed for the present paper was extracted from the Wastewater Treatment Station (WWTP) Galati, Romania. The physico-chemical parameters determined were: pH (upH), total organic carbon (TOC) (mg L⁻¹), N-total (mg L⁻¹), P-total (mg L⁻¹), N-NH₄ (mg L⁻¹), N-NO₂ (mg L⁻¹), N-NO₃ (mg L⁻¹), Fe-total (mg L⁻¹), Cr-total (mg L⁻¹), Cu (mg L⁻¹), Zn (mg L⁻¹), Cd (mg L⁻¹), Pb (mg L⁻¹), Ni (mg L⁻¹). The determination methods were electrometrical (pH, C, TSD) - with a portable HI 9828 HANNA electrodes committed multiparameter and spectrophotometric - with a Spectroquant NOVA 60 - Merck spectrophotometer and with specific Merck parameter kits. The tests made pointed out the fact that the sludge analysed is low heavy metal falling within the legal limits, the quantities of metals measured being much lower than the maximum allowed. The results of the tests made to determine the content of nutrients in the sewage sludge have shown that the existing nutrients may be used to increase the fertility of agricultural soils. Other tests were carried out on lands where sewage sludge was applied in order to establish the maximum quantity of sludge that may be used so as not to constitute a source of pollution. The tests were made on three plots: a first batch with no mud and no chemical fertilizers applied, a second batch on which only sewage sludge was applied, and a third batch on which small amounts of chemical fertilizers were applied in addition to sewage sludge. The results showed that the production increases when the soil is treated with sludge and small amounts of chemical fertilizers. Based on the results of the present research, a fertilization plan has been suggested. This plan should be reconsidered each year based on the crops planned, the yields proposed, the agrochemical indications, the sludge analysis, etc.

Keywords: agricultural use, crops, physico–chemical parameters, sewage sludge

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1129 Evaluation of Antarctic Bacteria as Potential Producers of Cellulolytic Enzymes of Industrial Interest

Authors: Claudio Lamilla, Andrés Santos, Vicente Llanquinao, Jocelyn Hermosilla, Leticia Barrientos

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The industry in general is very interested in improving and optimizing industrial processes in order to reduce the costs involved in obtaining raw materials and production. Thus, an interesting and cost-effective alternative is the incorporation of bioactive metabolites in such processes, being an example of this enzymes which catalyze efficiently a large number of enzymatic reactions of industrial and biotechnological interest. In the search for new sources of these active metabolites, Antarctica is one of the least explored places on our planet where the most drastic cold conditions, salinity, UVA-UVB and liquid water available are present, features that have shaped all life in this very harsh environment, especially bacteria that live in different Antarctic ecosystems, which have had to develop different strategies to adapt to these conditions, producing unique biochemical strategies. In this work the production of cellulolytic enzymes of seven bacterial strains isolated from marine sediments at different sites in the Antarctic was evaluated. Isolation of the strains was performed using serial dilutions in the culture medium at M115°C. The identification of the strains was performed using universal primers (27F and 1492R). The enzyme activity assays were performed on R2A medium, carboxy methyl cellulose (CMC)was added as substrate. Degradation of the substrate was revealed by adding Lugol. The results show that four of the tested strains produce enzymes which degrade CMC substrate. The molecular identifications, showed that these bacteria belong to the genus Streptomyces and Pseudoalteromonas, being Streptomyces strain who showed the highest activity. Only some bacteria in marine sediments have the ability to produce these enzymes, perhaps due to their greater adaptability to degrade at temperatures bordering zero degrees Celsius, some algae that are abundant in this environment and have cellulose as the main structure. The discovery of new enzymes adapted to cold is of great industrial interest, especially for paper, textiles, detergents, biofuels, food and agriculture. These enzymes represent 8% of industrial demand worldwide and is expected to increase their demand in the coming years. Mainly in the paper and food industry are required in extraction processes starch, protein and juices, as well as the animal feed industry where treating vegetables and grains helps improve the nutritional value of the food, all this clearly puts Antarctic microorganisms and their enzymes specifically as a potential contribution to industry and the novel biotechnological applications.

Keywords: antarctic, bacteria, biotechnological, cellulolytic enzymes

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1128 Production, Characterisation, and in vitro Degradation and Biocompatibility of a Solvent-Free Polylactic-Acid/Hydroxyapatite Composite for 3D-Printed Maxillofacial Bone-Regeneration Implants

Authors: Carlos Amnael Orozco-Diaz, Robert David Moorehead, Gwendolen Reilly, Fiona Gilchrist, Cheryl Ann Miller

Abstract:

The current gold-standard for maxillofacial reconstruction surgery (MRS) utilizes auto-grafted cancellous bone as a filler. This study was aimed towards developing a polylactic-acid/hydroxyapatite (PLA-HA) composite suitable for fused-deposition 3D printing. Functionalization of the polymer through the addition of HA was directed to promoting bone-regeneration properties so that the material can rival the performance of cancellous bone grafts in terms of bone-lesion repair. This kind of composite enables the production of MRS implants based off 3D-reconstructions from image studies – namely computed tomography – for anatomically-correct fitting. The present study encompassed in-vitro degradation and in-vitro biocompatibility profiling for 3D-printed PLA and PLA-HA composites. PLA filament (Verbatim Co.) and Captal S hydroxyapatite micro-scale HA powder (Plasma Biotal Ltd) were used to produce PLA-HA composites at 5, 10, and 20%-by-weight HA concentration. These were extruded into 3D-printing filament, and processed in a BFB-3000 3D-Printer (3D Systems Co.) into tensile specimens, and were mechanically challenged as per ASTM D638-03. Furthermore, tensile specimens were subjected to accelerated degradation in phosphate-buffered saline solution at 70°C for 23 days, as per ISO-10993-13-2010. This included monitoring of mass loss (through dry-weighing), crystallinity (through thermogravimetric analysis/differential thermal analysis), molecular weight (through gel-permeation chromatography), and tensile strength. In-vitro biocompatibility analysis included cell-viability and extracellular matrix deposition, which were performed both on flat surfaces and on 3D-constructs – both produced through 3D-printing. Discs of 1 cm in diameter and cubic 3D-meshes of 1 cm3 were 3D printed in PLA and PLA-HA composites (n = 6). The samples were seeded with 5000 MG-63 osteosarcoma-like cells, with cell viability extrapolated throughout 21 days via resazurin reduction assays. As evidence of osteogenicity, collagen and calcium deposition were indirectly estimated through Sirius Red staining and Alizarin Red staining respectively. Results have shown that 3D printed PLA loses structural integrity as early as the first day of accelerated degradation, which was significantly faster than the literature suggests. This was reflected in the loss of tensile strength down to untestable brittleness. During degradation, mass loss, molecular weight, and crystallinity behaved similarly to results found in similar studies for PLA. All composite versions and pure PLA were found to perform equivalent to tissue-culture plastic (TCP) in supporting the seeded-cell population. Significant differences (p = 0.05) were found on collagen deposition for higher HA concentrations, with composite samples performing better than pure PLA and TCP. Additionally, per-cell-calcium deposition on the 3D-meshes was significantly lower when comparing 3D-meshes to discs of the same material (p = 0.05). These results support the idea that 3D-printable PLA-HA composites are a viable resorbable material for artificial grafts for bone-regeneration. Degradation data suggests that 3D-printing of these materials – as opposed to other manufacturing methods – might result in faster resorption than currently-used PLA implants.

Keywords: bone regeneration implants, 3D-printing, in vitro testing, biocompatibility, polymer degradation, polymer-ceramic composites

Procedia PDF Downloads 154
1127 Management of Urine Recovery at the Building Level

Authors: Joao Almeida, Ana Azevedo, Myriam Kanoun-Boule, Maria Ines Santos, Antonio Tadeu

Abstract:

The effects of the increasing expansion of cities and climate changes have encouraged European countries and regions to adopt nature-based solutions with ability to mitigate environmental issues and improve life in cities. Among these strategies, green roofs and urban gardens have been considered ingenious solutions, since they have the desirable potential to improve air quality, prevent floods, reduce the heat island effect and restore biodiversity in cities. However, an additional consumption of fresh water and mineral nutrients is necessary to sustain larger green urban areas. This communication discusses the main technical features of a new system to manage urine recovery at the building level and its application in green roofs. The depletion of critical nutrients like phosphorus constitutes an emergency. In turn, their elimination through urine is one of the principal causes for their loss. Thus, urine recovery in buildings may offer numerous advantages, constituting a valuable fertilizer abundantly available in cities and reducing the load on wastewater treatment plants. Although several urine-diverting toilets have been developed for this purpose and some experiments using urine directly in agriculture have already been carried out in Europe, several challenges have emerged with this practice concerning collection, sanitization, storage and application of urine in buildings. To our best knowledge, current buildings are not designed to receive these systems and integrated solutions with ability to self-manage the whole process of urine recovery, including separation, maturation and storage phases, are not known. Additionally, if from a hygiene point of view human urine may be considered a relatively safe fertilizer, the risk of disease transmission needs to be carefully analysed. A reduction in microorganisms can be achieved by storing the urine in closed tanks. However, several factors may affect this process, which may result in a higher survival rate for some pathogens. In this work, urine effluent was collected under real conditions, stored in closed containers and kept in climatic chambers under variable conditions simulating cold, temperate and tropical climates. These samples were subjected to a first physicochemical and microbiological control, which was repeated over time. The results obtained so far suggest that maturation conditions were reached for all the three temperatures and that a storage period of less than three months is required to achieve a strong depletion of microorganisms. The authors are grateful for the Project WashOne (POCI-01-0247-FEDER-017461) funded by the Operational Program for Competitiveness and Internationalization (POCI) of Portugal 2020, with the support of the European Regional Development Fund (FEDER).

Keywords: sustainable green roofs and urban gardens, urban nutrient cycle, urine-based fertilizers, urine recovery in buildings

Procedia PDF Downloads 161
1126 One Pot Synthesis of Cu–Ni–S/Ni Foam for the Simultaneous Removal and Detection of Norfloxacin

Authors: Xincheng Jiang, Yanyan An, Yaoyao Huang, Wei Ding, Manli Sun, Hong Li, Huaili Zheng

Abstract:

The residual antibiotics in the environment will pose a threat to the environment and human health. Thus, efficient removal and rapid detection of norfloxacin (NOR) in wastewater is very important. The main sources of NOR pollution are the agricultural, pharmaceutical industry and hospital wastewater. The total consumption of NOR in China can reach 5440 tons per year. It is found that neither animals nor humans can totally absorb and metabolize NOR, resulting in the excretion of NOR into the environment. Therefore, residual NOR has been detected in water bodies. The hazards of NOR in wastewater lie in three aspects: (1) the removal capacity of the wastewater treatment plant for NOR is limited (it is reported that the average removal efficiency of NOR in the wastewater treatment plant is only 68%); (2) NOR entering the environment will lead to the emergence of drug-resistant strains; (3) NOR is toxic to many aquatic species. At present, the removal and detection technologies of NOR are applied separately, which leads to a cumbersome operation process. The development of simultaneous adsorption-flocculation removal and FTIR detection of pollutants has three advantages: (1) Adsorption-flocculation technology promotes the detection technology (the enrichment effect on the material surface improves the detection ability); (2) The integration of adsorption-flocculation technology and detection technology reduces the material cost and makes the operation easier; (3) FTIR detection technology endows the water treatment agent with the ability of molecular recognition and semi-quantitative detection for pollutants. Thus, it is of great significance to develop a smart water treatment material with high removal capacity and detection ability for pollutants. This study explored the feasibility of combining NOR removal method with the semi-quantitative detection method. A magnetic Cu-Ni-S/Ni foam was synthesized by in-situ loading Cu-Ni-S nanostructures on the surface of Ni foam. The novelty of this material is the combination of adsorption-flocculation technology and semi-quantitative detection technology. Batch experiments showed that Cu-Ni-S/Ni foam has a high removal rate of NOR (96.92%), wide pH adaptability (pH=4.0-10.0) and strong ion interference resistance (0.1-100 mmol/L). According to the Langmuir fitting model, the removal capacity can reach 417.4 mg/g at 25 °C, which is much higher than that of other water treatment agents reported in most studies. Characterization analysis indicated that the main removal mechanisms are surface complexation, cation bridging, electrostatic attraction, precipitation and flocculation. Transmission FTIR detection experiments showed that NOR on Cu-Ni-S/Ni foam has easily recognizable FTIR fingerprints; the intensity of characteristic peaks roughly reflects the concentration information to some extent. This semi-quantitative detection method has a wide linear range (5-100 mg/L) and a low limit of detection (4.6 mg/L). These results show that Cu-Ni-S/Ni foam has excellent removal performance and semi-quantitative detection ability of NOR molecules. This paper provides a new idea for designing and preparing multi-functional water treatment materials to achieve simultaneous removal and semi-quantitative detection of organic pollutants in water.

Keywords: adsorption-flocculation, antibiotics detection, Cu-Ni-S/Ni foam, norfloxacin

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1125 Green Organic Chemistry, a New Paradigm in Pharmaceutical Sciences

Authors: Pesaru Vigneshwar Reddy, Parvathaneni Pavan

Abstract:

Green organic chemistry which is the latest and one of the most researched topics now-a- days has been in demand since 1990’s. Majority of the research in green organic chemistry chemicals are some of the important starting materials for greater number of major chemical industries. The production of organic chemicals has raw materials (or) reagents for other application is major sector of manufacturing polymers, pharmaceuticals, pesticides, paints, artificial fibers, food additives etc. organic synthesis on a large scale compound to the labratory scale, involves the use of energy, basic chemical ingredients from the petro chemical sectors, catalyst and after the end of the reaction, seperation, purification, storage, packing distribution etc. During these processes there are many problems of health and safety for workers in addition to the environmental problems caused there by use and deposition as waste. Green chemistry with its 12 principles would like to see changes in conventional way that were used for decades to make synthetic organic chemical and the use of less toxic starting materials. Green chemistry would like to increase the efficiency of synthetic methods, to use less toxic solvents, reduce the stage of synthetic routes and minimize waste as far as practically possible. In this way, organic synthesis will be part of the effort for sustainable development Green chemistry is also interested for research and alternatives innovations on many practical aspects of organic synthesis in the university and research labaratory of institutions. By changing the methodologies of organic synthesis, health and safety will be advanced in the small scale laboratory level but also will be extended to the industrial large scale production a process through new techniques. The three key developments in green chemistry include the use of super critical carbondioxide as green solvent, aqueous hydrogen peroxide as an oxidising agent and use of hydrogen in asymmetric synthesis. It also focuses on replacing traditional methods of heating with that of modern methods of heating like microwaves traditions, so that carbon foot print should reduces as far as possible. Another beneficiary of this green chemistry is that it will reduce environmental pollution through the use of less toxic reagents, minimizing of waste and more bio-degradable biproducts. In this present paper some of the basic principles, approaches, and early achievements of green chemistry has a branch of chemistry that studies the laws of passing of chemical reactions is also considered, with the summarization of green chemistry principles. A discussion about E-factor, old and new synthesis of ibuprofen, microwave techniques, and some of the recent advancements also considered.

Keywords: energy, e-factor, carbon foot print, micro-wave, sono-chemistry, advancement

Procedia PDF Downloads 289
1124 Generalized Synchronization in Systems with a Complex Topology of Attractor

Authors: Olga I. Moskalenko, Vladislav A. Khanadeev, Anastasya D. Koloskova, Alexey A. Koronovskii, Anatoly A. Pivovarov

Abstract:

Generalized synchronization is one of the most intricate phenomena in nonlinear science. It can be observed both in systems with a unidirectional and mutual type of coupling including the complex networks. Such a phenomenon has a number of practical applications, for example, for the secure information transmission through the communication channel with a high level of noise. Known methods for the secure information transmission needs in the increase of the privacy of data transmission that arises a question about the observation of such phenomenon in systems with a complex topology of chaotic attractor possessing two or more positive Lyapunov exponents. The present report is devoted to the study of such phenomenon in two unidirectionally and mutually coupled dynamical systems being in chaotic (with one positive Lyapunov exponent) and hyperchaotic (with two or more positive Lyapunov exponents) regimes, respectively. As the systems under study, we have used two mutually coupled modified Lorenz oscillators and two unidirectionally coupled time-delayed generators. We have shown that in both cases the generalized synchronization regime can be detected by means of the calculation of Lyapunov exponents and phase tube approach whereas due to the complex topology of attractor the nearest neighbor method is misleading. Moreover, the auxiliary system approaches being the standard method for the synchronous regime observation, for the mutual type of coupling results in incorrect results. To calculate the Lyapunov exponents in time-delayed systems we have proposed an approach based on the modification of Gram-Schmidt orthogonalization procedure in the context of the time-delayed system. We have studied in detail the mechanisms resulting in the generalized synchronization regime onset paying a great attention to the field where one positive Lyapunov exponent has already been become negative whereas the second one is a positive yet. We have found the intermittency here and studied its characteristics. To detect the laminar phase lengths the method based on a calculation of local Lyapunov exponents has been proposed. The efficiency of the method has been verified using the example of two unidirectionally coupled Rössler systems being in the band chaos regime. We have revealed the main characteristics of intermittency, i.e. the distribution of the laminar phase lengths and dependence of the mean length of the laminar phases on the criticality parameter, for all systems studied in the report. This work has been supported by the Russian President's Council grant for the state support of young Russian scientists (project MK-531.2018.2).

Keywords: complex topology of attractor, generalized synchronization, hyperchaos, Lyapunov exponents

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1123 Case Report of Left Atrial Myxoma Diagnosed by Bedside Echocardiography

Authors: Anthony S. Machi, Joseph Minardi

Abstract:

We present a case report of left atrial myxoma diagnosed by bedside transesophageal (TEE) ultrasound. Left atrial myxoma is the most common benign cardiac tumor and can obstruct blood flow and cause valvular insufficiency. Common symptoms consist of dyspnea, pulmonary edema and other features of left heart failure in addition to thrombus release in the form of tumor fragments. The availability of bedside ultrasound equipment is essential for the quick diagnosis and treatment of various emergency conditions including cardiac neoplasms. A 48-year-old Caucasian female with a four-year history of an untreated renal mass and anemia presented to the ED with two months of sharp, intermittent, bilateral flank pain radiating into the abdomen. She also reported intermittent vomiting and constipation along with generalized body aches, night sweats, and 100-pound weight loss over last year. She had a CT in 2013 showing a 3 cm left renal mass and a second CT in April 2016 showing a 3.8 cm left renal mass along with a past medical history of diverticulosis, chronic bronchitis, dyspnea on exertion, uncontrolled hypertension, and hyperlipidemia. Her maternal family history is positive for breast cancer, hypertension, and Type II Diabetes. Her paternal family history is positive for stroke. She was a current everyday smoker with an 11 pack/year history. Alcohol and drug use were denied. Physical exam was notable for a Grade II/IV systolic murmur at the right upper sternal border, dyspnea on exertion without angina, and a tender left lower quadrant. Her vitals and labs were notable for a blood pressure of 144/96, heart rate of 96 beats per minute, pulse oximetry of 96%, hemoglobin of 7.6 g/dL, hypokalemia, hypochloremia, and multiple other abnormalities. Physicians ordered a CT to evaluate her flank pain which revealed a 7.2 x 8.9 x 10.5 cm mixed cystic/solid mass in the lower pole of the left kidney and a filling defect in the left atrium. Bedside TEE was ordered to follow up on the filling defect. TEE reported an ejection fraction of 60-65% and visualized a mobile 6 x 3 cm mass in the left atrium attached to the interatrial septum extending into the mitral valve. Cardiothoracic Surgery and Urology were consulted and confirmed a diagnosis of left atrial myxoma and clear cell renal cell carcinoma. The patient returned a week later due to worsening nausea and vomiting and underwent emergent nephrectomy, lymph node dissection, and colostomy due to a necrotic colon. Her condition declined over the next four months due to lung and brain metastases, infections, and other complications until she passed away.

Keywords: bedside ultrasound, echocardiography, emergency medicine, left atrial myxoma

Procedia PDF Downloads 325
1122 The Rehabilitation of The Covered Bridge Leclerc (P-00249) Passing Over the Bouchard Stream in LaSarre, Quebec

Authors: Nairy Kechichian

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The original Leclerc Bridge is a covered wooden bridge that is considered a Quebec heritage structure with an index of 60, making it a very important provincial bridge from a historical point of view. It was constructed in 1927 and is in the rural area of Abitibi-Temiscamingue. It is a “town Québécois” type of structure, which is generally rare but common for covered bridges in Abitibi-Temiscamingue. This type of structure is composed of two trusses on both sides formed with diagonals, internal bracings, uprights and top and bottom chords to allow the transmission of loads. This structure is mostly known for its solidity, lightweightness, and ease of construction. It is a single-span bridge with a length of 25.3 meters and allows the passage of one vehicle at a time with a 4.22-meter driving lane. The structure is composed of 2 trusses located at each end of the deck, two gabion foundations at both ends, uprights and top and bottom chords. WSP (Williams Sale Partnership) Canada inc. was mandated by the Transport Minister of Quebec in 2019 to increase the capacity of the bridge from 5 tons to 30.6 tons and rehabilitate it, as it has deteriorated quite significantly over the years. The bridge was damaged due to material deterioration over time, exposure to humidity, high load effects and insect infestation. To allow the passage of 3 axle trucks, as well as to keep the integrity of this heritage structure, the final design chosen to rehabilitate the bridge involved adding a new deck independent from the roof structure of the bridge. Essentially, new steel beams support the deck loads and the desired vehicle loads. The roof of the bridge is linked to the steel deck for lateral support, but it is isolated from the wooden deck. The roof is preserved for aesthetic reasons and remains intact as it is a heritage piece. Due to strict traffic management obstacles, an efficient construction method was put into place, which consisted of building a temporary bridge and moving the existing roof onto it to allow the circulation of vehicles on one side of the temporary bridge while providing a working space for the repairs of the roof on the other side to take place simultaneously. In parallel, this method allowed the demolition and reconstruction of the existing foundation, building a new steel deck, and transporting back the roof on the new bridge. One of the main criteria for the rehabilitation of the wooden bridge was to preserve, as much as possible, the existing patrimonial architectural design of the bridge. The project was completed successfully by the end of 2021.

Keywords: covered bridge, wood-steel, short span, town Québécois structure

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1121 Experimental Studies of the Reverse Load-Unloading Effect on the Mechanical, Linear and Nonlinear Elastic Properties of n-AMg6/C60 Nanocomposite

Authors: Aleksandr I. Korobov, Natalia V. Shirgina, Aleksey I. Kokshaiskiy, Vyacheslav M. Prokhorov

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The paper presents the results of an experimental study of the effect of reverse mechanical load-unloading on the mechanical, linear, and nonlinear elastic properties of n-AMg6/C60 nanocomposite. Samples for experimental studies of n-AMg6/C60 nanocomposite were obtained by grinding AMg6 polycrystalline alloy in a planetary mill with 0.3 wt % of C60 fullerite in an argon atmosphere. The resulting product consisted of 200-500-micron agglomerates of nanoparticles. X-ray coherent scattering (CSL) method has shown that the average nanoparticle size is 40-60 nm. The resulting preform was extruded at high temperature. Modifications of C60 fullerite interferes the process of recrystallization at grain boundaries. In the samples of n-AMg6/C60 nanocomposite, the load curve is measured: the dependence of the mechanical stress σ on the strain of the sample ε under its multi-cycle load-unloading process till its destruction. The hysteresis dependence σ = σ(ε) was observed, and insignificant residual strain ε < 0.005 were recorded. At σ≈500 MPa and ε≈0.025, the sample was destroyed. The destruction of the sample was fragile. Microhardness was measured before and after destruction of the sample. It was found that the loading-unloading process led to an increase in its microhardness. The effect of the reversible mechanical stress on the linear and nonlinear elastic properties of the n-AMg6/C60 nanocomposite was studied experimentally by ultrasonic method on the automated complex Ritec RAM-5000 SNAP SYSTEM. In the n-AMg6/C60 nanocomposite, the velocities of the longitudinal and shear bulk waves were measured with the pulse method, and all the second-order elasticity coefficients and their dependence on the magnitude of the reversible mechanical stress applied to the sample were calculated. Studies of nonlinear elastic properties of the n-AMg6/C60 nanocomposite at reversible load-unloading of the sample were carried out with the spectral method. At arbitrary values of the strain of the sample (up to its breakage), the dependence of the amplitude of the second longitudinal acoustic harmonic at a frequency of 2f = 10MHz on the amplitude of the first harmonic at a frequency f = 5MHz of the acoustic wave is measured. Based on the results of these measurements, the values of the nonlinear acoustic parameter in the n-AMg6/C60 nanocomposite sample at different mechanical stress were determined. The obtained results can be used in solid-state physics, materials science, for development of new techniques for nondestructive testing of structural materials using methods of nonlinear acoustic diagnostics. This study was supported by the Russian Science Foundation (project №14-22-00042).

Keywords: nanocomposite, generation of acoustic harmonics, nonlinear acoustic parameter, hysteresis

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1120 Temperature-Dependent Post-Mortem Changes in Human Cardiac Troponin-T (cTnT): An Approach in Determining Postmortem Interval

Authors: Sachil Kumar, Anoop Kumar Verma, Wahid Ali, Uma Shankar Singh

Abstract:

Globally approximately 55.3 million people die each year. In the India there were 95 lakh annual deaths in 2013. The number of deaths resulted from homicides, suicides and unintentional injuries in the same period was about 5.7 lakh. The ever-increasing crime rate necessitated the development of methods for determining time since death. An erroneous time of death window can lead investigators down the wrong path or possibly focus a case on an innocent suspect. In this regard a research was carried out by analyzing the temperature dependent degradation of a Cardiac Troponin-T protein (cTnT) in the myocardium postmortem as a marker for time since death. Cardiac tissue samples were collected from (n=6) medico-legal autopsies, (in the Department of Forensic Medicine and Toxicology, King George’s Medical University, Lucknow India) after informed consent from the relatives and studied post-mortem degradation by incubation of the cardiac tissue at room temperature (20±2 OC), 12 0C, 25 0C and 37 0C for different time periods ((~5, 26, 50, 84, 132, 157, 180, 205, and 230 hours). The cases included were the subjects of road traffic accidents (RTA) without any prior history of disease who died in the hospital and their exact time of death was known. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS-PAGE) and visualization by Western blot using cTnT specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc. The data shows a distinct temporal profile corresponding to the degradation of cTnT by proteases found in cardiac muscle. The disappearance of intact cTnT and the appearance of lower molecular weight bands are easily observed. Western blot data clearly showed the intact protein at 42 kDa, two major (27 kDa, 10kDa) fragments, two additional minor fragments (32 kDa) and formation of low molecular weight fragments as time increases. At 12 0C the intensity of band (intact cTnT) decreased steadily as compared to RT, 25 0C and 37 0C. Overall, both PMI and temperature had a statistically significant effect where the greatest amount of protein breakdown was observed within the first 38 h and at the highest temperature, 37 0C. The combination of high temperature (37 0C) and long Postmortem interval (105.15 hrs) had the most drastic effect on the breakdown of cTnT. If the percent intact cTnT is calculated from the total area integrated within a Western blot lane, then the percent intact cTnT shows a pseudo-first order relationship when plotted against the log of the time postmortem. These plots show a good coefficient of correlation of r = 0.95 (p=0.003) for the regression of the human heart at different temperature conditions. The data presented demonstrates that this technique can provide an extended time range during which Postmortem interval can be more accurately estimated.

Keywords: degradation, postmortem interval, proteolysis, temperature, troponin

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1119 Protonic Conductivity Highlighted by Impedance Measurement of Y-Doped BaZrO3 Synthesized by Supercritical Hydrothermal Process

Authors: Melanie Francois, Gilles Caboche, Frederic Demoisson, Francois Maeght, Maria Paola Carpanese, Lionel Combemale, Pascal Briois

Abstract:

Finding new clean, and efficient way for energy production is one of the actual global challenges. Advances in fuel cell technology have shown that, for few years, Protonic Ceramic Fuel Cell (PCFC) has attracted much attention in the field of new hydrogen energy thanks to their lower working temperature, possible higher efficiency, and better durability than classical SOFC. On the contrary of SOFC, where O²⁻ oxygen ion is the charge carrier, PCFC works with H⁺ proton as a charge carrier. Consequently, the lower activation energy of proton diffusion compared to the one of oxygen ion explains those benefits and allows PCFC to work in the 400-600°C temperature range. Doped-BaCeO₃ is currently the most chosen material for this application because of its high protonic conductivity; for example, BaCe₀.₉Y₀.₁O₃ δ exhibits a total conductivity of 1.5×10⁻² S.cm⁻¹ at 600°C in wet H₂. However, BaCeO₃ based perovskite has low stability in H₂O and/or CO₂ containing atmosphere, which limits their practical application. On the contrary, BaZrO₃ based perovskite exhibits good chemical stability but lower total conductivity than BaCeO₃ due to its larger grain boundary resistance. By substituting zirconium with 20% of yttrium, it is possible to achieve a total conductivity of 2.5×10⁻² S.cm⁻¹ at 600°C in wet H₂. However, the high refractory property of BaZr₀.₈Y₀.₂O₃-δ (noted BZY20) causes problems to obtain a dense membrane with large grains. Thereby, using a synthesis process that gives fine particles could allow better sinterability and thus decrease the number of grain boundaries leading to a higher total conductivity. In this work, BaZr₀.₈Y₀.₂O₃-δ have been synthesized by classical batch hydrothermal device and by a continuous hydrothermal device developed at ICB laboratory. The two variants of this process are able to work in supercritical conditions, leading to the formation of nanoparticles, which could be sintered at a lower temperature. The as-synthesized powder exhibits the right composition for the perovskite phase, impurities such as BaCO₃ and YO-OH were detected at very low concentration. Microstructural investigation and densification rate measurement showed that the addition of 1 wt% of ZnO as sintering aid and a sintering at 1550°C for 5 hours give high densified electrolyte material. Furthermore, it is necessary to heat the synthesized powder prior to the sintering to prevent the formation of secondary phases. It is assumed that this thermal treatment homogenizes the crystal structure of the powder and reduces the number of defects into the bulk grains. Electrochemical impedance spectroscopy investigations in various atmospheres and a large range of temperature (200-700°C) were then performed on sintered samples, and the protonic conductivity of BZY20 has been highlighted. Further experiments on half-cell, NiO-BZY20 as anode and BZY20 as electrolyte, are in progress.

Keywords: hydrothermal synthesis, impedance measurement, Y-doped BaZrO₃, proton conductor

Procedia PDF Downloads 131
1118 Loading by Number Strategy for Commercial Vehicles

Authors: Ramalan Musa Yerima

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The paper titled “loading by number” explained a strategy developed recently by Zonal Commanding Officer of the Federal Road Safety Corps of Nigeria, covering Sokoto, Kebbi and Zamfara States of Northern Nigeria. The strategy is aimed at reducing competition, which will invariably leads to the reduction in speed, reduction in dangerous driving, reduction in crash rate, reduction in injuries, reduction in property damages and reduction in death through road traffic crashes (RTC). This research paper presents a study focused on enhancing the safety of commercial vehicles. The background of this study highlights the alarming statistics related to commercial vehicle crashes in Nigeria with focus on Sokoto, Kebbi and Zamfara States, which often result in significant damage to property, loss of lives, and economic costs. The significance and aims is to investigate and propose effective strategy to enhance the safety of commercial vehicles. The study recognizes the pressing need for heightened safety measures in commercial transportation, as it impacts not only the well-being of drivers and passengers but also the overall public safety. To achieve the objectives, an examination of accident data, including causes and contributing factors, was performed to identify critical areas for improvement. The major finding of the study reveals that when competition comes into play within the realm of commercial driving, it has detrimental effects on road safety and resource management. Commercial drivers are pushed to complete their routes quickly, deliver goods on time or they pushed themselves to arrive quickly for more passengers and new contracts. This competitive environment, fuelled by internal and external pressures such as tight deadlines, poverty and greed, often leads to sad endings. The study recommend that if a strategy called loading by number is integrated with other multiple safety measures such as driver training programs, regulatory enforcement, and infrastructure improvements, commercial vehicle safety can be significantly enhanced. "Loading by Number” approach is design to ensure that the sequence of departure of drivers from motor park ‘A’ would be communicated to motor park officials of park ‘B’, which would be considered sequentially when giving them returning passengers, regardless of the first to arrive. In conclusion, this paper underscores the significance of improving the safety measures of commercial vehicles, as they are often larger and heavier than other vehicles on the road. Whenever they are involved in accidents, the consequences can be more severe. Commercial vehicles are also frequently involved in long-haul or interstate transportation, which means they cover longer distances and spend more time on the road. This increased exposure to driving conditions increases the probability of accidents occurring. By implementing the suggested measures, policymakers, transportation authorities, and industry stakeholders can work collectively towards ensuring a safer commercial transportation system.

Keywords: commercial, safety, strategy, transportation

Procedia PDF Downloads 53
1117 The Role of Microbes in Organic Sustainable Agriculture and Plant Protection

Authors: Koppula Prawan, Kehinde D. Oyeyemi, Kushal P. Singh

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As people become more conscious of the detrimental consequences of conventional agricultural practices on the environment and human health, organic, sustainable agriculture and plant protection employing microorganisms have grown in importance. Although the use of microorganisms in agriculture is a centuries-old tradition, it has recently attracted renewed interest as a sustainable alternative to chemical-based plant protection and fertilization. Healthy soil is the cornerstone of sustainable agriculture, and microbes are essential to this process. Synthetic fertilizers and pesticides can destroy the beneficial microorganisms in the soil, upsetting the ecosystem's equilibrium. By utilizing organic farming's natural practices, such as the usage of microbes, it aims to maintain and improve the health of the soil. Microbes have several functions in agriculture, including nitrogen fixation, phosphorus solubilization, and disease suppression. Nitrogen fixation is the process by which certain microbes, such as rhizobia and Azotobacter, convert atmospheric nitrogen into a form that plants can use. Phosphorus solubilization involves the conversion of insoluble phosphorus into a soluble form that plants can absorb. Disease suppression involves the use of microbes to control plant diseases by competing with pathogenic organisms for resources or by producing antimicrobial compounds. Microbes can be applied to plants through seed coatings, foliar sprays, or soil inoculants. Seed coatings involve applying a mixture of microbes and nutrients to the surface of seeds before planting. Foliar sprays involve applying microbes and nutrients to the leaves of plants during the growing season. Soil inoculants involve adding microbes to the soil before planting. The use of microbes in plant protection and fertilization has several advantages over conventional methods. Firstly, microbes are natural and non-toxic, making them safe for human health and the environment. Secondly, microbes have the ability to adapt to changing environmental conditions, making them more resilient to drought and other stressors. Finally, the use of microbes can reduce the need for synthetic fertilizers and pesticides, reducing costs and minimizing environmental impact. In conclusion, organic, sustainable agriculture and plant protection using microbes are an effective and sustainable alternatives to conventional farming practices. The use of microbes can help to preserve and enhance soil health, increase plant productivity, and reduce the need for synthetic fertilizers and pesticides. As the demand for organic and sustainable agriculture continues to grow, the use of microbes is likely to become more widespread, providing a more environmentally friendly and sustainable future for agriculture.

Keywords: microbes, inoculants, fertilization, soil health, conventional.

Procedia PDF Downloads 77
1116 Dealing with the Spaces: Ultra Conservative Approach from Childhood to Adulthood

Authors: Maryam Firouzmandi, Moosa Miri

Abstract:

Common reasons for early tooth loss are trauma, extraction due to caries or periodontal disease and congenital missing. The remaining space after tooth loss may cause functional and esthetic problems. Therefore restorative dentists should attempt to manage these spaces using conservative methods. The goal is to restore the lost esthetic and function, prevent phonetic, self-esteem and personality problems and tongue habits. Preserving alveolar bone is also of great importance during the growth stage. Purpose: When deciding about the management of the missing tooth, space implants are contradicted until the completion of dentoalveolar development. Even in adulthood, due to systemic or periodontal problems or biological and economic issues, the implant might not be indicated. In this article, the alternative conservative restorative methods of space maintenance are going to be discussed. Essix retainers are made chair-side as easy as forming a custom bleaching tray with some modifications. They are esthetically acceptable and not expensive. These temporaries provide support for the lips but could not be used during function. Mini-screw-supported temporaries are another option for maintaining the space, especially after orthodontic treatment when there is a time lag between the termination of orthodontic treatment and definitive restoration. Two techniques will be presented for this kind of restoration: Denture tooth pontic or a composite crown. The benefits are alveolar bone preservation, Physiologic pressure on the alveolar ridge to increase its density and even can be retained until the completion of the definitive treatment. Bonded fixed partial denture includes Maryland bridge, fiber-reinforced composite bridge, resin-bonded bridge, and ceramic bonded bridge. These types of bridges are recommended to be used after a pubertal growth spurt and a recent meta-analysis considered their clinical success similar to conventional FDPs and implant-supported crowns. However, they have several advantages that are going to be discussed by presenting some clinical examples. Practical instruction on how to construct an FRC bridge and a novel chair-side Maryland bridge will be given by means of clinical cases. Clinical relevance: minimally invasive options should always be considered and destruction of healthy enamel and dentin during the preparation phase should be avoided as much as possible.

Keywords: tooth missing, fiber-reinforced composite, Maryland, Essix retainers, screw-retained restoration

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1115 Determination of Energy and Nutrients Composition of Potential Ready-to-Use Therapeutic Food Formulated from Locally Available Resources

Authors: Amina Sa'id Muhammad, Asmau Ishaq Alhassan, Beba Raymond, Fatima Bello

Abstract:

Severe acute malnutrition (SAM) remains a major killer of children under five years of age. Nigeria has the second highest burden of stunted children in the world, with a national prevalence rate of 32 percent of children under five. An estimated 2 million children in Nigeria suffer from severe acute malnutrition (SAM), and 3.9% of children in northwest Nigeria suffer from SAM, which is significantly higher than the national average of 2.1%. Community-Based Management of Acute Malnutrition (CMAM) has proven to be an effective intervention in the treatment of SAM in children using Ready-to-Use Therapeutic Food (RUTF). Ready-to-use therapeutic food (RUTF) is a key component for the treatment of Severe Acute Malnutrition. It contains all the energy and nutrients required for rapid catch-up growth and used particularly in the treatment of children over 6 months of age with SAM without medical complications. However, almost all RUTFs are currently imported to Nigeria from other countries. Shortages of RUTF due to logistics (shipping costs, delays, donor fatigue etc) and funding issues present a threat to the achievement of the 2030 World Health Assembly (WHA) targets for reducing malnutrition in addition to 2030 SDGs 2 (Zero Hunger), 3 (Good Health and Wellbeing), 12 (Responsible Consumption and Production), and 17 (Partnerships for the Goals), thus undermining its effectiveness in combating malnutrition On the other hand, the availability of human and material resources that will aid local production of RUTF presents an opportunity to fill in the gap in regular RUTF supply. About one thousand Nigerian children die of malnutrition-related causes every day, reaching a total of 361,000 each year. Owing to the high burden of malnutrition in Nigeria, the local production of RUTF is a logical step, that will ensure increased availability, acceptability, access, and efficiency in supply, and at lower costs. Objective(s): The objectives of this study were therefore, to formulate RUTF from locally available resources and to determine its energy and nutrients composition, incommensurate with the standard/commercial RUTF. Methods: Three samples of RUTF were formulated using locally available resources (soya beans, wheat, rice, baobab, brown-sugar, date palm and soya oil); which were subjected to various analysis to determine their energy/proximate composition, vitamin and mineral contents and organoleptic properties were also determined using sensory evaluation. Results: The energy values of the three samples of locally produced RUTF were found to be in conformity with WHO recommendation of ≥ 500 kcal per 100g. The energy values of the three RUTF samples produced in the current study were found to be 563.08, 503.67 and 528.98 kcal respectively. Sample A, B and C had protein content of 13.56% 16.71% and 14.62% respectively, which were higher than that of commercial RUTF (10.9%). Conclusions/recommendations: The locally formulated RUTF samples had energy value of more than 500 kcal per 100g; with an appreciable amount of macro and micro nutrients. The appearance, taste, flavor and general acceptability of the formulated RUTF samples were also commendable.

Keywords: energy, malnutrition, nutrients, RUTF

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1114 Influence of Controlled Retting on the Quality of the Hemp Fibres Harvested at the Seed Maturity by Using a Designed Lab-Scale Pilot Unit

Authors: Brahim Mazian, Anne Bergeret, Jean-Charles Benezet, Sandrine Bayle, Luc Malhautier

Abstract:

Hemp fibers are increasingly used as reinforcements in polymer matrix composites due to their competitive performance (low density, mechanical properties and biodegradability) compared to conventional fibres such as glass fibers. However, the huge variation of their biochemical, physical and mechanical properties limits the use of these natural fibres in structural applications when high consistency and homogeneity are required. In the hemp industry, traditional processes termed field retting are commonly used to facilitate the extraction and separation of stem fibers. This retting treatment consists to spread out the stems on the ground for a duration ranging from a few days to several weeks. Microorganisms (fungi and bacteria) grow on the stem surface and produce enzymes that degrade pectinolytic substances in the middle lamellae surrounding the fibers. This operation depends on the weather conditions and is currently carried out very empirically in the fields so that a large variability in the hemp fibers quality (mechanical properties, color, morphology, chemical composition…) is resulting. Nonetheless, if controlled, retting might be favorable for good properties of hemp fibers and then of hemp fibers reinforced composites. Therefore, the present study aims to investigate the influence of controlled retting within a designed environmental chamber (lab-scale pilot unit) on the quality of the hemp fibres harvested at the seed maturity growth stage. Various assessments were applied directly on fibers: color observations, morphological (optical microscope), surface (ESEM), biochemical (gravimetry) analysis, spectrocolorimetric measurements (pectins content), thermogravimetric analysis (TGA) and tensile testing. The results reveal that controlled retting leads to a rapid change of color from yellow to dark grey due to development of microbial communities (fungi and bacteria) at the stem surface. An increase of thermal stability of fibres due to the removal of non-cellulosic components along retting is also observed. A separation of bast fibers to elementary fibers occurred with an evolution of chemical composition (degradation of pectins) and a rapid decrease in tensile properties (380MPa to 170MPa after 3 weeks) due to accelerated retting process. The influence of controlled retting on the biocomposite material (PP / hemp fibers) properties is under investigation.

Keywords: controlled retting, hemp fibre, mechanical properties, thermal stability

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1113 School Accidents in Educational Establishment in Tunisia: A Five Years Retrospective Survey in the Governorate of Mahdia

Authors: Lamia Bouzgarrou, Amira Omrane, Leila Mrabet, Taoufik Khalfallah

Abstract:

Background and aims: School accidents are one of the leading causes of morbidity and mortality among pupils and students. Indeed, they may induce an elevated number of lost school days, heavy emotional and physical disabilities, and financial costs on the victims and their families. This study aims to evaluate the annual incidence of school accidents in the central Tunisian governorate of Mahdia and to identify the epidemiological profile of victims and risk factors of these accidents. Methods: A retrospective study was conducted over the period of 5 school years, focusing on school accidents that occurred in public educational institutions (primary, basic, secondary and university) in the governorate of Mahdia (area = 2 966 km² and number of inhabitants in 2014 = 410 812). All accidents declared near the only official insurance of this type of injuries (MASU: Mutual School and University Accidents), and initially taken in charge at the University Hospital of Mahdia were included. Data was collected from the MASU reporting forms and the medical records of emergency and other specialized hospital departments. Results: With 3248 identified victims, the annual incidence of school accidents was equal to 0.69 per 100 pupils and students per year. The average age of victims was 14.51 ± 0.059 years and the sex ratio was 1.58. Pupils aged between 12 and 15 years, were concerned by 46.7% of the identified accidents. The practice of sports was the most relevant circumstances of these accidents (76.2 %). In 56.58 % of cases, falls were the leading mechanism. Bruises and fractures were the most frequent lesions (32.43 % and 30.51 %). Serious school accidents were noted in 28% of cases with hospitalization in 2.27 % of them. The average lost school days, was 12.23±1.73 days. Accidents occurring during sports or leisure activities were significantly more serious (p= 0.021). Furthermore, the frequency of hospitalization was significantly higher among boys (2.81% vs. 1.43%; p= 0.035), students ≤11 years (p= 0.008), and following crush trauma (p= 0.000). In addition, the surgical interventions were statistically more frequent among male victims (p=0.00), accidents occurring during physical education sessions (p=0.000); those associated to falls (p=0.000) and to crushes mechanisms (p=0.002), and injuries affecting lower limbs (p=0.000). Following this Multi-varied analysis concluded that the severity of school accident is correlated to the activity practiced during the trauma and the geographical location of the school. Conclusion: Children and adolescents are one of the most vulnerable groups against incidents with the risk of permanent disability, mainly related to the perturbation of the growth process and physiological limitations. Our five-year study, objectified a real elevate incidence of school accident among children and adolescents, with a considerable rate of severe injuries. In any community, the promotion of adolescents and children’s health is an important indicator of the public health level. Thus, it’s important to develop a multidisciplinary prevention strategy of school accident, based on safety and security rules and adapted to the specificity of our context.

Keywords: children and adolescents, children health, injuries and disability, school accident

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1112 Detection of High Fructose Corn Syrup in Honey by Near Infrared Spectroscopy and Chemometrics

Authors: Mercedes Bertotto, Marcelo Bello, Hector Goicoechea, Veronica Fusca

Abstract:

The National Service of Agri-Food Health and Quality (SENASA), controls honey to detect contamination by synthetic or natural chemical substances and establishes and controls the traceability of the product. The utility of near-infrared spectroscopy for the detection of adulteration of honey with high fructose corn syrup (HFCS) was investigated. First of all, a mixture of different authentic artisanal Argentinian honey was prepared to cover as much heterogeneity as possible. Then, mixtures were prepared by adding different concentrations of high fructose corn syrup (HFCS) to samples of the honey pool. 237 samples were used, 108 of them were authentic honey and 129 samples corresponded to honey adulterated with HFCS between 1 and 10%. They were stored unrefrigerated from time of production until scanning and were not filtered after receipt in the laboratory. Immediately prior to spectral collection, honey was incubated at 40°C overnight to dissolve any crystalline material, manually stirred to achieve homogeneity and adjusted to a standard solids content (70° Brix) with distilled water. Adulterant solutions were also adjusted to 70° Brix. Samples were measured by NIR spectroscopy in the range of 650 to 7000 cm⁻¹. The technique of specular reflectance was used, with a lens aperture range of 150 mm. Pretreatment of the spectra was performed by Standard Normal Variate (SNV). The ant colony optimization genetic algorithm sample selection (ACOGASS) graphical interface was used, using MATLAB version 5.3, to select the variables with the greatest discriminating power. The data set was divided into a validation set and a calibration set, using the Kennard-Stone (KS) algorithm. A combined method of Potential Functions (PF) was chosen together with Partial Least Square Linear Discriminant Analysis (PLS-DA). Different estimators of the predictive capacity of the model were compared, which were obtained using a decreasing number of groups, which implies more demanding validation conditions. The optimal number of latent variables was selected as the number associated with the minimum error and the smallest number of unassigned samples. Once the optimal number of latent variables was defined, we proceeded to apply the model to the training samples. With the calibrated model for the training samples, we proceeded to study the validation samples. The calibrated model that combines the potential function methods and PLSDA can be considered reliable and stable since its performance in future samples is expected to be comparable to that achieved for the training samples. By use of Potential Functions (PF) and Partial Least Square Linear Discriminant Analysis (PLS-DA) classification, authentic honey and honey adulterated with HFCS could be identified with a correct classification rate of 97.9%. The results showed that NIR in combination with the PT and PLS-DS methods can be a simple, fast and low-cost technique for the detection of HFCS in honey with high sensitivity and power of discrimination.

Keywords: adulteration, multivariate analysis, potential functions, regression

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