Search results for: thermal improvement
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7517

Search results for: thermal improvement

497 Vagal Nerve Stimulator as a Treatment Approach in CHARGE Syndrome: A Case Report

Authors: Roya Vakili, Lekaa Elhajjmoussa, Barzin Omidi-Shal, Kim Blake

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Objective: The purpose of this case report is to highlight the successful treatment of a patient with Coloboma, Heart defect, Atresia choanae, Retarded growth and development, Genital hypoplasia, Ear anomalies/deafness, (CHARGE syndrome) using a vagal nerve stimulator (VNS). Background: This is the first documented case report, to the authors' best knowledge, for a patient with CHARGE syndrome, epilepsy, autism, and postural orthostatic tachycardia syndrome (POTS) that was successfully treated with an implanted VNS therapeutic device. Methodology: The study is a case report. Results: This is the case of a 24-year-old female patient with CHARGE syndrome (non-random association of anomalies Coloboma, Heart defect, Atresia choanae, Retarded growth and development, Genital hypoplasia, Ear anomalies/deafness) and several other comorbidities including refractory epilepsy, Patent Ductus Arteriosus (PDA) and POTS who had significant improvement of her symptoms after VNS implantation. She was a VNS candidate given her longstanding history of drug-resistant epilepsy and current disposition secondary to CHARGE syndrome. Prior to VNS implantation, she experienced three generalized seizures a year and daily POTS-related symptoms. She was having frequent lightheadedness and syncope spells due to a rapid heart rate and low blood pressure. The VNS device was set to detect a rapid heart rate and send appropriate stimulation anytime the heart rate exceeded 20% of the patient’s normal baseline. The VNS device demonstrated frequent elevated heart rates and concurrent VNS release every 8 minutes in addition to the programmed events. Following VNS installation, the patient became more active, alert, and communicative and was able to verbally communicate with words she was unable to say prior. Her GI symptoms also improved, as she was able to tolerate food better orally in addition to her G and J tube, likely another result of the vagal nerve stimulation. Additionally, the patient’s seizures and POTS-related cardiac events appeared to be well controlled. She had prolonged electroencephalogram (EEG) testing, showing no significant change in epileptiform activity. Improvements in the patient’s disposition are believed to be secondary to parasympathetic stimulation, adequate heart rate control, and GI stimulation, in addition to behavioral changes and other benefits via her implanted VNS. Conclusion: VNS showed promising results in improving the patient's quality of life and managing her diverse symptoms, including dysautonomia, POTs, gastrointestinal mobility, cognitive functioning as well seizure control.

Keywords: autism, POTs, CHARGE, VNS

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496 Control of Asthma in Children with Asthma during the Containment Period following the Covid-19 Pandemic

Authors: Meryam Labyad, Karima Fakiri, Widad Lahmini, Ghizlane Draiss, Mohamed Bouskraoui, Nadia Ouzennou

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Background: Asthma is the most common chronic disease in children, affecting nearly 235 million people worldwide (OMS). In Morocco, asthma is much more common in children than in adults; the prevalence rate in children between 13 and 14 years of age is 20%.1 This pathology is marked by high morbidity, a significant impact on the quality of life and development of children 2 This requires a rigorous management strategy in order to achieve clinical control and reduce any risk to the patient 3 A search for aggravating factors is mandatory if a child has difficulty maintaining good asthma control. The objective of the present study is to describe asthma control during this confinement period in children aged 4 to 11 years followed by a pneumo-paediatric consultation. For children whose asthma is not controlled, a search for associations with promoting factors and adherence to treatment is also among the objectives of the study. Knowing the level of asthma control and influencing factors is a therapeutic priority in order to reduce hospitalizations and emergency care use. Objective: To assess asthma control and determine the factors influencing asthma levels in children with asthma during confinement following the COVID 19 pandemic. Method: Prospective cross-sectional study by questionnaire and structured interview among 66 asthmatic children followed in pediatric pneumology consultation at the CHU MED VI of Marrakech from 13/06/2020 to 13/07/2020, asthma control was assessed by the Childhood Asthma Control Test (C-ACT). Results: 66 children and their parents were included (mean age is 7.5 years), asthma was associated with allergic rhinitis (13.5% of cases), conjunctivitis (9% of cases), eczema (12% of cases), occurrence of infection (10.5% of cases). The period of confinement was marked by a decrease in the number of asthma attacks translated by a decrease in the number of emergency room visits (7.5%) of these asthmatic children, control was well controlled in 71% of the children, this control was significantly associated with good adherence to treatment (p<0.001), no infection (p<0.001) and no conjunctivitis (p=002) or rhinitis (p<0.001). This improvement in asthma control during confinement can be explained by the measures taken in the Kingdom to prevent the spread of COVID 19 (school closures, reduction in industrial activity, fewer means of transport, etc.), leading to a decrease in children's exposure to triggers, which justifies the decrease in the number of children having had an infection, allergic rhinitis or conjunctivitis during this period. In addition, the close monitoring of parents resulted in better therapeutic adherence (42.4% were fully observant). Confinement was positively perceived by 68% of the parents; this perception is significantly associated with the level of asthma control (p<0.001). Conclusion: Maintaining good control can be achieved through improved therapeutic adherence and avoidance of triggers, both of which were achieved during the containment period following the VIDOC pandemic 19.

Keywords: Asthma, control , COVID-19 , children

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495 Seafloor and Sea Surface Modelling in the East Coast Region of North America

Authors: Magdalena Idzikowska, Katarzyna Pająk, Kamil Kowalczyk

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Seafloor topography is a fundamental issue in geological, geophysical, and oceanographic studies. Single-beam or multibeam sonars attached to the hulls of ships are used to emit a hydroacoustic signal from transducers and reproduce the topography of the seabed. This solution provides relevant accuracy and spatial resolution. Bathymetric data from ships surveys provides National Centers for Environmental Information – National Oceanic and Atmospheric Administration. Unfortunately, most of the seabed is still unidentified, as there are still many gaps to be explored between ship survey tracks. Moreover, such measurements are very expensive and time-consuming. The solution is raster bathymetric models shared by The General Bathymetric Chart of the Oceans. The offered products are a compilation of different sets of data - raw or processed. Indirect data for the development of bathymetric models are also measurements of gravity anomalies. Some forms of seafloor relief (e.g. seamounts) increase the force of the Earth's pull, leading to changes in the sea surface. Based on satellite altimetry data, Sea Surface Height and marine gravity anomalies can be estimated, and based on the anomalies, it’s possible to infer the structure of the seabed. The main goal of the work is to create regional bathymetric models and models of the sea surface in the area of the east coast of North America – a region of seamounts and undulating seafloor. The research includes an analysis of the methods and techniques used, an evaluation of the interpolation algorithms used, model thickening, and the creation of grid models. Obtained data are raster bathymetric models in NetCDF format, survey data from multibeam soundings in MB-System format, and satellite altimetry data from Copernicus Marine Environment Monitoring Service. The methodology includes data extraction, processing, mapping, and spatial analysis. Visualization of the obtained results was carried out with Geographic Information System tools. The result is an extension of the state of the knowledge of the quality and usefulness of the data used for seabed and sea surface modeling and knowledge of the accuracy of the generated models. Sea level is averaged over time and space (excluding waves, tides, etc.). Its changes, along with knowledge of the topography of the ocean floor - inform us indirectly about the volume of the entire water ocean. The true shape of the ocean surface is further varied by such phenomena as tides, differences in atmospheric pressure, wind systems, thermal expansion of water, or phases of ocean circulation. Depending on the location of the point, the higher the depth, the lower the trend of sea level change. Studies show that combining data sets, from different sources, with different accuracies can affect the quality of sea surface and seafloor topography models.

Keywords: seafloor, sea surface height, bathymetry, satellite altimetry

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494 Effects of Endurance Training and Thyme Consumption on Neuropeptide Y in Untrained Men

Authors: M. Ghasemi, S.Fazelifar

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Abstract Aim: Over-weight is not desirable and has implications for health and in the case of athletes affects performance. Exercise is a strategy used to counteract overweight owing to create a negative energy balance by increasing energy expenditure and influencing appetite regulating hormones. Interestingly, recent studies have revealed inhibitory effects of exercise on the hunger associated with these hormones in healthy subjects Neuropeptide Y(NPY) is a 36 amino acid protein that is a powerful stimulant appetite. NPY is an important central orexigenic hormone predominantly produced by the hypothalamus, and recently found to be secreted in adipose tissue. This neurotransmitter is secreted in the brain and autonomic nervous system. On the other hand, research has shown that thyme in addition to various properties, also affects the appetite. The purpose of this study was to determine Effects of eight weeks endurance training and thyme consumption on neuropeptide Y in untrained men. Methodology: 36 Healthy untrained men (mean body weight 78.25±3.2 kg, height 176±6.8 cm, age 34.32±4.54 years and BMI 29.1±4.3 kg/m2) voluntarily participated in this study . Subjects were randomly divided into four groups: 1. control, 2. Endurance training, 3. Thyme 4. Endurance training + Thyme. Amount of 10cc Blood sampling were obtained pre-test and post-test (after 8 weeks). The taken blood samples were centrifuged at 1500 × g for 15 min then plasma was stored at -20 °C until analysis. Endurance training consisted three session per week with 60% -75% of reserve heart rate for eight weeks. Exclusion criteria were history of gastrointestinal, endocrine, cardiovascular or psychological disease, and consuming any supplementation, alcohol and tobacco products. Descriptive statistics including means, standard deviations, and ranges were calculated for all measures. K-S test to determine the normality of the data and analysis of variance for repeated measures was used to analyze the data. A significant difference in the p<0/05 accepted. Results: Results showed that aerobic training significantly reduced body weight, body mass index, percent body fat, but significant increase observed in maximal oxygen consumption level (p ≤ 0/05). The neuropeptide Y levels were significantly increased after exercise. Analysis of data determined that there was no significant difference between the four groups. Conclusion: Appetite control plays a critical role in the competition between energy consumption and energy expenditure. The results of this study showed that endurance training and thyme consumption can be cause improvement in physiological parameters such as increasing aerobic capacity, reduction of fat mass and improve body composition in untrained men.

Keywords: Endurance training, neuropeptide Y, thyme, untrained men

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493 Sugarcane Trash Biochar: Effect of the Temperature in the Porosity

Authors: Gabriela T. Nakashima, Elias R. D. Padilla, Joao L. Barros, Gabriela B. Belini, Hiroyuki Yamamoto, Fabio M. Yamaji

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Biochar can be an alternative to use sugarcane trash. Biochar is a solid material obtained from pyrolysis, that is a biomass thermal degradation with low or no O₂ concentration. Pyrolysis transforms the carbon that is commonly found in other organic structures into a carbon with more stability that can resist microbial decomposition. Biochar has a versatility of uses such as soil fertility, carbon sequestration, energy generation, ecological restoration, and soil remediation. Biochar has a great ability to retain water and nutrients in the soil so that this material can improve the efficiency of irrigation and fertilization. The aim of this study was to characterize biochar produced from sugarcane trash in three different pyrolysis temperatures and determine the lowest temperature with the high yield and carbon content. Physical characterization of this biochar was performed to help the evaluation for the best production conditions. Sugarcane (Saccharum officinarum) trash was collected at Corredeira Farm, located in Ibaté, São Paulo State, Brazil. The farm has 800 hectares of planted area with an average yield of 87 t·ha⁻¹. The sugarcane varieties planted on the farm are: RB 855453, RB 867515, RB 855536, SP 803280, SP 813250. Sugarcane trash was dried and crushed into 50 mm pieces. Crucibles and lids were used to settle the sugarcane trash samples. The higher amount of sugarcane trash was added to the crucible to avoid the O₂ concentration. Biochar production was performed in three different pyrolysis temperatures (200°C, 325°C, 450°C) in 2 hours residence time in the muffle furnace. Gravimetric yield of biochar was obtained. Proximate analysis of biochar was done using ASTM E-872 and ABNT NBR 8112. Volatile matter and ash content were calculated by direct weight loss and fixed carbon content calculated by difference. Porosity measurement was evaluated using an automatic gas adsorption device, Autosorb-1, with CO₂ described by Nakatani. Approximately 0.5 g of biochar in 2 mm particle sizes were used for each measurement. Vacuum outgassing was performed as a pre-treatment in different conditions for each biochar temperature. The pore size distribution of micropores was determined using Horváth-Kawazoe method. Biochar presented different colors for each treatment. Biochar - 200°C presented a higher number of pieces with 10mm or more and did not present the dark black color like other treatments after 2 h residence time in muffle furnace. Also, this treatment had the higher content of volatiles and the lower amount of fixed carbon. In porosity analysis, while the temperature treatments increase, the amount of pores also increase. The increase in temperature resulted in a biochar with a better quality. The pores in biochar can help in the soil aeration, adsorption, water retention. Acknowledgment: This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brazil – PROAP-CAPES, PDSE and CAPES - Finance Code 001.

Keywords: proximate analysis, pyrolysis, soil amendment, sugarcane straw

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492 Preparedness Level of Disaster Management Institutions in Context of Floods in Delhi

Authors: Aditi Madan, Jayant Kumar Routray

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Purpose: Over the years flood related risks have compounded due to increasing vulnerability caused by rapid urbanisation and growing population. This increase is an indication of the need for enhancing the preparedness of institutions to respond to floods. The study describes disaster management structure and its linkages with institutions involved in managing disasters. It addresses issues and challenges associated with readiness of disaster management institutions to respond to floods. It suggests policy options for enhancing the current state of readiness of institutions to respond by considering factors like institutional, manpower, financial, technical, leadership & networking, training and awareness programs, monitoring and evaluation. Methodology: The study is based on qualitative data with statements and outputs from primary and secondary sources to understand the institutional framework for disaster management in India. Primary data included field visits, interviews with officials from institutions managing disasters and the affected community to identify the challenges faced in engaging national, state, district and local level institutions in managing disasters. For focus group discussions, meetings were held with district project officers and coordinators, local officials, community based organisation, civil defence volunteers and community heads. These discussions were held to identify the challenges associated with preparedness to respond of institutions to floods. Findings: Results show that disasters are handled by district authority and the role of local institutions is limited to a reactive role during disaster. Data also indicates that although the existing institutional setup is well coordinated at the district level but needs improvement at the local level. Wide variations exist in awareness and perception among the officials engaged in managing disasters. Additionally, their roles and responsibilities need to be clearly defined with adequate budget and dedicated permanent staff for managing disasters. Institutions need to utilise the existing manpower through proper delegation of work. Originality: The study suggests that disaster risk reduction needs to focus more towards inclusivity of the local urban bodies. Wide variations exist in awareness and perception among the officials engaged in managing disasters. In order to ensure community participation, it is important to address their social and economic problems since such issues can overshadow attempts made for reducing risks. Thus, this paper suggests development of direct linkages among institutions and community for enhancing preparedness to respond to floods.

Keywords: preparedness, response, disaster, flood, community, institution

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491 Kidnapping of Migrants by Drug Cartels in Mexico as a New Trend in Contemporary Slavery

Authors: Itze Coronel Salomon

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The rise of organized crime and violence related to drug cartels in Mexico has created serious challenges for the authorities to provide security to those who live within its borders. However, to achieve a significant improvement in security is absolute respect for fundamental human rights by the authorities. Irregular migrants in Mexico are at serious risk of abuse. Research by Amnesty International as well as reports of the NHRC (National Human Rights) in Mexico, have indicated the major humanitarian crisis faced by thousands of migrants traveling in the shadows. However, the true extent of the problem remains invisible to the general population. The fact that federal and state governments leave no proper record of abuse and do not publish reliable data contributes to ignorance and misinformation, often spread by the media that portray migrants as the source of crime rather than their victims. Discrimination and intolerance against irregular migrants can generate greater hostility and exclusion. According to the modus operandi that has been recorded criminal organizations and criminal groups linked to drug trafficking structures deprive migrants of their liberty for forced labor and illegal activities related to drug trafficking, even some have been kidnapped for be trained as murderers . If the victim or their family cannot pay the ransom, the kidnapped person may suffer torture, mutilation and amputation of limbs or death. Migrant women are victims of sexual abuse during her abduction as well. In 2011, at least 177 bodies were identified in the largest mass grave found in Mexico, located in the town of San Fernando, in the border state of Tamaulipas, most of the victims were killed by blunt instruments, and most seemed to be immigrants and travelers passing through the country. With dozens of small graves discovered in northern Mexico, this may suggest a change in tactics between organized crime groups to the different means of obtaining revenue and reduce murder profile methods. Competition and conflict over territorial control drug trafficking can provide strong incentives for organized crime groups send signals of violence to the authorities and rival groups. However, as some Mexican organized crime groups are increasingly looking to take advantage of income and vulnerable groups, such as Central American migrants seem less interested in advertising his work to authorities and others, and more interested in evading detection and confrontation. This paper pretends to analyze the introduction of this new trend of kidnapping migrants for forced labors by drug cartels in Mexico into the forms of contemporary slavery and its implications.

Keywords: international law, migration, transnational organized crime

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490 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

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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

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489 Caged Compounds as Light-Dependent Initiators for Enzyme Catalysis Reactions

Authors: Emma Castiglioni, Nigel Scrutton, Derren Heyes, Alistair Fielding

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By using light as trigger, it is possible to study many biological processes, such as the activity of genes, proteins, and other molecules, with precise spatiotemporal control. Caged compounds, where biologically active molecules are generated from an inert precursor upon laser photolysis, offer the potential to initiate such biological reactions with high temporal resolution. As light acts as the trigger for cleaving the protecting group, the ‘caging’ technique provides a number of advantages as it can be intracellular, rapid and controlled in a quantitative manner. We are developing caging strategies to study the catalytic cycle of a number of enzyme systems, such as nitric oxide synthase and ethanolamine ammonia lyase. These include the use of caged substrates, caged electrons and the possibility of caging the enzyme itself. In addition, we are developing a novel freeze-quench instrument to study these reactions, which combines rapid mixing and flashing capabilities. Reaction intermediates will be trapped at low temperatures and will be analysed by using electron paramagnetic resonance (EPR) spectroscopy to identify the involvement of any radical species during catalysis. EPR techniques typically require relatively long measurement times and very often, low temperatures to fully characterise these short-lived species. Therefore, common rapid mixing techniques, such as stopped-flow or quench-flow are not directly suitable. However, the combination of rapid freeze-quench (RFQ) followed by EPR analysis provides the ideal approach to kinetically trap and spectroscopically characterise these transient radical species. In a typical RFQ experiment, two reagent solutions are delivered to the mixer via two syringes driven by a pneumatic actuator or stepper motor. The new mixed solution is then sprayed into a cryogenic liquid or surface, and the frozen sample is then collected and packed into an EPR tube for analysis. The earliest RFQ instrument consisted of a hydraulic ram unit as a drive unit with direct spraying of the sample into a cryogenic liquid (nitrogen, isopentane or petroleum). Improvements to the RFQ technique have arisen from the design of new mixers in order to reduce both the volume and the mixing time. In addition, the cryogenic isopentane bath has been coupled to a filtering system or replaced by spraying the solution onto a surface that is frozen via thermal conductivity with a cryogenic liquid. In our work, we are developing a novel RFQ instrument which combines the freeze-quench technology with flashing capabilities to enable the studies of both thermally-activated and light-activated biological reactions. This instrument also uses a new rotating plate design based on magnetic couplings and removes the need for mechanical motorised rotation, which can otherwise be problematic at cryogenic temperatures.

Keywords: caged compounds, freeze-quench apparatus, photolysis, radicals

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488 Benign Recurrent Unilateral Abducens (6th) Nerve Palsy in 14 Months Old Girl: A Case Report

Authors: Khaled Alabduljabbar

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Background: Benign, isolated, recurrent sixth nerve palsy is very rare in children. Here we report a case of recurrent abducens nerve palsy with no obvious etiology. It is a diagnosis of exclusion. A recurrent benign form of 6th nerve palsy, a rarer still palsy, has been described in the literature, and it is of most likely secondary to inflammatory causes, e.g, following viral and bacterial infections. Purpose: To present a case of 14 months old girl with recurrent attacks of isolated left sixth cranial nerve palsy following upper respiratory tract infection. Observation: The patient presented to opthalmology clinic with sudden onset of inward deviation (esotropia) of the left eye with a compensatory left face turn one week following signs of upper respiratory tract infection. Ophthalmological examination revealed large angle esotropia of the left eye in primary position, with complete limitation of abduction of the left eye, no palpebral fissure changes, and abnormal position of the head (left face turn). Visual acuity was normal, and no significant refractive error on cycloplegic refraction for her age. Fundus examination was normal with no evidence of papilledema. There was no relative afferent pupillary defect (RAPD) and no anisocoria. Past medical history and family history were unremarkable, with no history of convulsion attacks or head trauma. Additional workout include CBC. Erythrocyte sedimentation rate, Urgent magnetic resonance imaging (MRI), and angiography of the brain were performed and demonstrated the absence of intracranial and orbital lesions. Referral to pediatric neurologist was also done and concluded no significant finding. The patient showed improvement of the left sixth cranial nerve palsy and left face turn over a period of two months. Seven months since the first attack, she experienced a recurrent attack of left eye esotropia with left face turn concurrent with URTI. The rest of eye examination was again unremarkable. CT scan and MRI scan of brain and orbit were performed and showed only signs of sinusitis with no intracranial pathology. The palsy resolved spontaneously within two months. A third episode of left 6th nerve palsy occurred 6 months later, whichrecovered over one month. Examination and neuroimagingwere unremarkable. A diagnosis of benign recurrent left 6th cranial nerve palsy was made. Conclusion: Benign sixth cranial nerve palsy is always a diagnosis of exclusion given the more serious and life-threatening alternative causes. It seems to have a good prognosis with only supportive measures. The likelihood of benign 6th cranial nerve palsy to resolve completely and spontaneously is high. Observation for at least 6 months without intervention is advisable.

Keywords: 6th nerve pasy, abducens nerve pasy, recurrent nerve palsy, cranial nerve palsy

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487 Characterization of Surface Microstructures on Bio-Based PLA Fabricated with Nano-Imprint Lithography

Authors: D. Bikiaris, M. Nerantzaki, I. Koliakou, A. Francone, N. Kehagias

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In the present study, the formation of structures in poly(lactic acid) (PLA) has been investigated with respect to producing areas of regular, superficial features with dimensions comparable to those of cells or biological macromolecules. Nanoimprint lithography, a method of pattern replication in polymers, has been used for the production of features ranging from tens of micrometers, covering areas up to 1 cm², down to hundreds of nanometers. Both micro- and nano-structures were faithfully replicated. Potentially, PLA has wide uses within biomedical fields, from implantable medical devices, including screws and pins, to membrane applications, such as wound covers, and even as an injectable polymer for, for example, lipoatrophy. The possibility of fabricating structured PLA surfaces, with structures of the dimensions associated with cells or biological macro- molecules, is of interest in fields such as cellular engineering. Imprint-based technologies have demonstrated the ability to selectively imprint polymer films over large areas resulting in 3D imprints over flat, curved or pre-patterned surfaces. Here, we compare nano-patterned with nano-patterned by nanoimprint lithography (NIL) PLA film. A silicon nanostructured stamp (provided by Nanotypos company) having positive and negative protrusions was used to pattern PLA films by means of thermal NIL. The polymer film was heated from 40°C to 60°C above its Tg and embossed with a pressure of 60 bars for 3 min. The stamp and substrate were demolded at room temperature. Scanning electron microscope (SEM) images showed good replication fidelity of the replicated Si stamp. Contact-angle measurements suggested that positive microstructuring of the polymer (where features protrude from the polymer surface) produced a more hydrophilic surface than negative micro-structuring. The ability to structure the surface of the poly(lactic acid), allied to the polymer’s post-processing transparency and proven biocompatibility. Films produced in this were also shown to enhance the aligned attachment behavior and proliferation of Wharton’s Jelly Mesenchymal Stem cells, leading to the observed growth contact guidance. The bacterial attachment patterns of some bacteria, highlighted that the nano-patterned PLA structure can reduce the propensity for the bacteria to attach to the surface, with a greater bactericidal being demonstrated activity against the Staphylococcus aureus cells. These biocompatible, micro- and nanopatterned PLA surfaces could be useful for polymer– cell interaction experiments at dimensions at, or below, that of individual cells. Indeed, post-fabrication modification of the microstructured PLA surface, with materials such as collagen (which can further reduce the hydrophobicity of the surface), will extend the range of applications, possibly through the use of PLA’s inherent biodegradability. Further study is being undertaken to examine whether these structures promote cell growth on the polymer surface.

Keywords: poly(lactic acid), nano-imprint lithography, anti-bacterial properties, PLA

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486 Agriculture and Forests: A Perception of Farmers on Sustainable Agro-Ecological Practices

Authors: Kever Gomes, Rosana Martins

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The use of environmental indicators is today an important strategy for analyzing the sustainability of agricultural systems. Despite of the considerable importance of family agriculture for Brazilian economy, sustainable agricultural practices are still weakly known, and the known ones, underused. Currently, economic aspects of the relationship between man and nature lead to the destruction of natural ecosystems, which justifies the urgent need for dissemination and usage of new sustainable production techniques. The study shows the agro-social and social-cultural trajectory of the farmers and hypothesis are advanced on what would imply the adoption of agroforestry systems in family agriculture. This study aimed to investigate aspects related to the perception of sustainable agriculture, especially on agroforestry systems in farms of farmers from Distrito Federal-Brazil. Agro-social characteristics of farmers were systematized considering their perceptions about agroforestry systems for the preparation of proposal for a program of Environmental Services Payment, intended for families who are involved in the various activities of home gardens. This study used qualitative methodological approaches of quantitative research, using descriptive exploratory research. To get the necessary elements for the intended analysis, interviews were conducted at 40 heads of households of which 15 were men and 25 women. The results were analyzed using descriptive statistics, having been considered in the analysis the frequency, consistency, coherence and originality of responses. It was found that the lack of financial resources and lack of technical assistance are limiting factors for the dissemination and use of sustainable agricultural practices. Considering the great number of species found for the main categories of use, it can be inferred that the home gardens play important functions for the interviewed families, contributing for the food and medicine production destined for the consumption by the families themselves, and also playing an important esthetic function thanks to the variety of their ornamental plants. The wealth of these home gardens may be related to the rural origin and to the culture of the owners, who still keep a cultivation tradition. It was found that the products obtained from the home gardens contributed for the diet’s variety of the informants, representing a promising potential for the improvement of the population alimentation. The study reached the conclusion over the need to motivate the interest of these farmers to seek information and resources to enable the implementation of Agroforestry projects, including the recovery of areas in their properties, even those distinct from their backyards. The study shows the agro-social and social-cultural trajectory of the farmers and hypothesis are advanced on what would imply the adoption of agroforestry systems in family agriculture.

Keywords: agro-biodiversity, natural conservation, silviculture, urban agriculture

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485 Metal-Semiconductor Transition in Ultra-Thin Titanium Oxynitride Films Deposited by ALD

Authors: Farzan Gity, Lida Ansari, Ian M. Povey, Roger E. Nagle, James C. Greer

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Titanium nitride (TiN) films have been widely used in variety of fields, due to its unique electrical, chemical, physical and mechanical properties, including low electrical resistivity, chemical stability, and high thermal conductivity. In microelectronic devices, thin continuous TiN films are commonly used as diffusion barrier and metal gate material. However, as the film thickness decreases below a few nanometers, electrical properties of the film alter considerably. In this study, the physical and electrical characteristics of 1.5nm to 22nm thin films deposited by Plasma-Enhanced Atomic Layer Deposition (PE-ALD) using Tetrakis(dimethylamino)titanium(IV), (TDMAT) chemistry and Ar/N2 plasma on 80nm SiO2 capped in-situ by 2nm Al2O3 are investigated. ALD technique allows uniformly-thick films at monolayer level in a highly controlled manner. The chemistry incorporates low level of oxygen into the TiN films forming titanium oxynitride (TiON). Thickness of the films is characterized by Transmission Electron Microscopy (TEM) which confirms the uniformity of the films. Surface morphology of the films is investigated by Atomic Force Microscopy (AFM) indicating sub-nanometer surface roughness. Hall measurements are performed to determine the parameters such as carrier mobility, type and concentration, as well as resistivity. The >5nm-thick films exhibit metallic behavior; however, we have observed that thin film resistivity is modulated significantly by film thickness such that there are more than 5 orders of magnitude increment in the sheet resistance at room temperature when comparing 5nm and 1.5nm films. Scattering effects at interfaces and grain boundaries could play a role in thickness-dependent resistivity in addition to quantum confinement effect that could occur at ultra-thin films: based on our measurements the carrier concentration is decreased from 1.5E22 1/cm3 to 5.5E17 1/cm3, while the mobility is increased from < 0.1 cm2/V.s to ~4 cm2/V.s for the 5nm and 1.5nm films, respectively. Also, measurements at different temperatures indicate that the resistivity is relatively constant for the 5nm film, while for the 1.5nm film more than 2 orders of magnitude reduction has been observed over the range of 220K to 400K. The activation energy of the 2.5nm and 1.5nm films is 30meV and 125meV, respectively, indicating that the TiON ultra-thin films are exhibiting semiconducting behaviour attributing this effect to a metal-semiconductor transition. By the same token, the contact is no longer Ohmic for the thinnest film (i.e., 1.5nm-thick film); hence, a modified lift-off process was developed to selectively deposit thicker films allowing us to perform electrical measurements with low contact resistance on the raised contact regions. Our atomic scale simulations based on molecular dynamic-generated amorphous TiON structures with low oxygen content confirm our experimental observations indicating highly n-type thin films.

Keywords: activation energy, ALD, metal-semiconductor transition, resistivity, titanium oxynitride, ultra-thin film

Procedia PDF Downloads 282
484 An Audit to Look at the Management of Paediatric Peri Orbital Cellulitis in a District General Hospital, Emergency Department

Authors: Ruth Green, Samantha Milton, Rinal Desai

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Background/Aims: Eye pain/swelling/redness is a common presentation to Barnet General Hospital (a district general hospital), pediatric emergency department, and is managed by both the pediatric and emergency teams. The management of each child differs dramatically depending on the healthcare professional who reviews them. There also appears to be confusion in diagnosis between periorbital cellulitis, pre-septal cellulitis, and orbital cellulitis. Pre septal cellulitis refers to an inflammation of the eyelids and soft tissue anterior to the orbital septum. In contrast, orbital cellulitis is a serious, rapidly progressive infection of soft tissues located posterior to the orbital septum. Pre-septal cellulitis is more prevalent and less serious than orbital cellulitis, although it may be part of a continuous spectrum if untreated. Pre-septal cellulitis should there be diagnosed and treated urgently to prevent spread to the septum. For the purpose of the audit, the term periorbital cellulitis has been used as an umbrella term for all spectrums of this infection. The audit aimed to look at, how as a whole, the department is diagnosing and managing orbital and pre-septal cellulitis. Gold Standard: Patients of the same age and diagnosis should be treated with the same medication, advice, and follow-up. Method: Data was collected retrospectively from pediatric patients ( < 18years) who attended the emergency department from June 2019 to February 2020 who had been coded as pre-septal cellulitis, periorbital cellulitis, orbital cellulitis, or eye pain/swelling/redness. Demographics, signs and symptoms, management, and follow-up were recorded for all patients with any of the diagnoses of pre-septal, periorbital, or orbital cellulitis. A Microsoft Excel spreadsheet was used to record the anonymised data. Results: There were vast discrepancies in the diagnosis, management, and follow-up of patients with periorbital cellulitis. Conclusion/Discussion: The audit concluded there is no uniform approach to managing periorbital cellulitis in Barnet General Hospital Paediatric Emergency Department. Healthcare professionals misdiagnosed conjunctivitis as periorbital cellulitis, and adequate steps did not appear to be documented on excluding red flag signs and symptoms of patients presenting. There was no consistency in follow-up, with some patients having timely phone reviews or clinical reviews for mild symptoms. Advice given by the staff was appropriate, and patients did return when symptoms got worse and were treated accordingly. Plan: Given the inconsistency, a gold standard care pathway or local easily accessible clinical guideline can be developed to help with the diagnosis and management of periorbital cellulitis. Along with this, a teaching session can be carried out for the staff of the pediatric team and emergency department to disseminate the teaching. Following the introduction of a guideline and teaching sessions, patients notes can be re-reviewed to check improvement in patient care.

Keywords: periorbital cellulitis, preseptal cellulitis, orbital cellulitis, erythematous eyelid

Procedia PDF Downloads 119
483 Fuels and Platform Chemicals Production from Lignocellulosic Biomass: Current Status and Future Prospects

Authors: Chandan Kundu, Sankar Bhattacharya

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A significant disadvantage of fossil fuel energy production is the considerable amount of carbon dioxide (CO₂) released, which is one of the contributors to climate change. Apart from environmental concerns, changing fossil fuel prices have pushed society gradually towards renewable energy sources in recent years. Biomass is a plentiful and renewable resource and a source of carbon. Recent years have seen increased research interest in generating fuels and chemicals from biomass. Unlike fossil-based resources, biomass is composed of lignocellulosic material, which does not contribute to the increase in atmospheric CO₂ over a longer term. These considerations contribute to the current move of the chemical industry from non-renewable feedstock to renewable biomass. This presentation focuses on generating bio-oil and two major platform chemicals that can potentially improve the environment. Thermochemical processes such as pyrolysis are considered viable methods for producing bio-oil and biomass-based platform chemicals. Fluidized bed reactors, on the other hand, are known to boost bio-oil yields during pyrolysis due to their superior mixing and heat transfer features, as well as their scalability. This review and the associated experimental work are focused on the thermochemical conversion of biomass to bio-oil and two high-value platform chemicals, Levoglucosenone (LGO) and 5-Chloromethyl furfural (5-CMF), in a fluidized bed reactor. These two active molecules with distinct features can potentially be useful monomers in the chemical and pharmaceutical industries since they are well adapted to the manufacture of biologically active products. This process took several meticulous steps. To begin, the biomass was delignified using a peracetic acid pretreatment to remove lignin. Because of its complicated structure, biomass must be pretreated to remove the lignin, increasing access to the carbohydrate components and converting them to platform chemicals. The biomass was then characterized by Thermogravimetric analysis, Synchrotron-based THz spectroscopy, and in-situ DRIFTS in the laboratory. Based on the results, a continuous-feeding fluidized bed reactor system was constructed to generate platform chemicals from pretreated biomass using hydrogen chloride acid-gas as a catalyst. The procedure also yields biochar, which has a number of potential applications, including soil remediation, wastewater treatment, electrode production, and energy resource utilization. Consequently, this research also includes a preliminary experimental evaluation of the biochar's prospective applications. The biochar obtained was evaluated for its CO₂ and steam reactivity. The outline of the presentation will comprise the following: Biomass pretreatment for effective delignification Mechanistic study of the thermal and thermochemical conversion of biomass Thermochemical conversion of untreated and pretreated biomass in the presence of an acid catalyst to produce LGO and CMF A thermo-catalytic process for the production of LGO and 5-CMF in a continuously-fed fluidized bed reactor and efficient separation of chemicals Use of biochar generated from the platform chemicals production through gasification

Keywords: biomass, pretreatment, pyrolysis, levoglucosenone

Procedia PDF Downloads 122
482 Participatory Approach: A Tool for Improving Food Security and Empowering a Local Community in Chitima, Mozambique

Authors: Matias Hargreaves, Martin Del Valle, Diego Rodriguez, Riveros Jose Luis

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Trough years, all kind of social development projects have tried to solve social problems such as hunger, poverty, malnutrition, food insecurity, among others, with poor success. Both private and state initiatives have invested resources in several countries and communities. Nevertheless, most of these initiatives are scientific or external developers-centered, with a lack of local participation. This compromises the sustainability of any intervention and also leads to a poor empowerment of local community. The participatory approach aims to rescue and enhance the local knowledge since it recognizes that this kind of problems are better known by native actors. The objective of the study was to describe the role played by the community empowerment on food security improvement in the NGO “O Viveiro” (15°43'37.77"S; 32°46'27.53"E) and Barrio Broma village (15°43'58.78"S; 32°46'7.27"E) in Chitima, Mozambique. A center for training in goat livestock and orchard was build. A community orchard was co-constructed between foreign technicians and local actors. The prototype was installed in February, 2016 by the technician team and local community with 16 m2 as a nursery garden. Two orchard workshops were conducted in order to design a sustainable productive model which mixes both local and technological approaches. Two goat meat workshops were conducted in order to describe local methods and train the community to conduce their own techniques with high sanitary and productive standards. Technician team stayed in Mozambique until May, 2016. The quorum for the orchard workshops was 20 and 14 persons respectively, which represents 100% and 70%of the total requested quorum (20). For the goat meat workshops were 4 and 5 persons, which representa80% and 100% of the total requested quorum (5). Until August, 2016, the orchard is 3.219 m2 and it grows several vegetables as beans, chili pepper, garlic, onion, tomatoes, lettuce, sweet potato, yuca potato, cabbage, eggplant, papaya trees, mango, and cassava. The process of increasing in size and diversification of vegetables grown was led entirely by the local community. In connection with this, the local community started to harvest and began to sell the vegetable products at the local market. At the meat goat workshops, local participants rescued a local knowledge by describing and practicing a traditional way to process goat meat by drying it outdoors and then doing a smoked treatment. This information might contribute to describe the level of empowerment of this community, and thus give evidence of acceptance of foreign intervention for improving their own proceedings and traditions.

Keywords: children malnutrition, food security, Local community, participatory approach

Procedia PDF Downloads 265
481 Resolving a Piping Vibration Problem by Installing Viscous Damper Supports

Authors: Carlos Herrera Sierralta, Husain M. Muslim, Meshal T. Alsaiari, Daniel Fischer

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Preventing piping fatigue flow induced vibration in the Oil & Gas sector demands not only the constant development of engineering design methodologies based on available software packages, but also special piping support technologies for designing safe and reliable piping systems. The vast majority of piping vibration problems in the Oil & Gas industry are provoked by the process flow characteristics which are basically intrinsically related to the fluid properties, the type of service and its different operational scenarios. In general, the corrective actions recommended for flow induced vibration in piping systems can be grouped in two major areas: those which affect the excitation mechanisms typically associated to process variables, and those which affect the response mechanism of the pipework per se, and the pipework associated steel support structure. Where possible the first option is to try to solve the flow induced problem from the excitation mechanism perspective. However, in producing facilities the approach of changing process parameters might not always be convenient as it could lead to reduction of production rates or it may require the shutdown of the system in order to perform the required piping modification. That impediment might lead to a second option, which is to modify the response of the piping system to excitation generated by the type of process flow. In principle, the action of shifting the natural frequency of the system well above the frequency inherent to the process always favours the elimination, or considerably reduces, the level of vibration experienced by the piping system. Tightening up the clearances at the supports (ideally zero gap), and adding new static supports at the system, are typical ways of increasing the natural frequency of the piping system. However, only stiffening the piping system may not be sufficient to resolve the vibration problem, and in some cases, it might not be feasible to implement it at all, as the available piping layout could create limitations on adding supports due to thermal expansion/contraction requirements. In these cases, utilization of viscous damper supports could be recommended as these devices can allow relatively large quasi-static movement of piping while providing sufficient capabilities of dissipating the vibration. Therefore, when correctly selected and installed, viscous damper supports can provide a significant effect on the response of the piping system over a wide range of frequencies. Viscous dampers cannot be used to support sustained, static loads. This paper shows over a real case example, a methodology which allows to determine the selection of the viscous damper supports via a dynamic analysis model. By implementing this methodology, it was possible to resolve the piping vibration problem throughout redesigning adequately the existing static piping supports and by adding new viscous dampers supports. This was conducted on-stream at the oil crude pipeline in question without the necessity of reducing the production of the plant. Concluding that the application of the methodology of this paper can be applied to solve similar cases in a straightforward manner.

Keywords: dynamic analysis, flow induced vibration, piping supports, turbulent flow, slug flow, viscous damper

Procedia PDF Downloads 128
480 Linear Evolution of Compressible Görtler Vortices Subject to Free-Stream Vortical Disturbances

Authors: Samuele Viaro, Pierre Ricco

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Görtler instabilities generate in boundary layers from an unbalance between pressure and centrifugal forces caused by concave surfaces. Their spatial streamwise evolution influences transition to turbulence. It is therefore important to understand even the early stages where perturbations, still small, grow linearly and could be controlled more easily. This work presents a rigorous theoretical framework for compressible flows using the linearized unsteady boundary region equations, where only the streamwise pressure gradient and streamwise diffusion terms are neglected from the full governing equations of fluid motion. Boundary and initial conditions are imposed through an asymptotic analysis in order to account for the interaction of the boundary layer with free-stream turbulence. The resulting parabolic system is discretize with a second-order finite difference scheme. Realistic flow parameters are chosen from wind tunnel studies performed at supersonic and subsonic conditions. The Mach number ranges from 0.5 to 8, with two different radii of curvature, 5 m and 10 m, frequencies up to 2000 Hz, and vortex spanwise wavelengths from 5 mm to 20 mm. The evolution of the perturbation flow is shown through velocity, temperature, pressure profiles relatively close to the leading edge, where non-linear effects can still be neglected, and growth rate. Results show that a global stabilizing effect exists with the increase of Mach number, frequency, spanwise wavenumber and radius of curvature. In particular, at high Mach numbers curvature effects are less pronounced and thermal streaks become stronger than velocity streaks. This increase of temperature perturbations saturates at approximately Mach 4 flows, and is limited in the early stage of growth, near the leading edge. In general, Görtler vortices evolve closer to the surface with respect to a flat plate scenario but their location shifts toward the edge of the boundary layer as the Mach number increases. In fact, a jet-like behavior appears for steady vortices having small spanwise wavelengths (less than 10 mm) at Mach 8, creating a region of unperturbed flow close to the wall. A similar response is also found at the highest frequency considered for a Mach 3 flow. Larger vortices are found to have a higher growth rate but are less influenced by the Mach number. An eigenvalue approach is also employed to study the amplification of the perturbations sufficiently downstream from the leading edge. These eigenvalue results are compared with the ones obtained through the initial value approach with inhomogeneous free-stream boundary conditions. All of the parameters here studied have a significant influence on the evolution of the instabilities for the Görtler problem which is indeed highly dependent on initial conditions.

Keywords: compressible boundary layers, Görtler instabilities, receptivity, turbulence transition

Procedia PDF Downloads 245
479 The Effect of Different Strength Training Methods on Muscle Strength, Body Composition and Factors Affecting Endurance Performance

Authors: Shaher A. I. Shalfawi, Fredrik Hviding, Bjornar Kjellstadli

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The main purpose of this study was to measure the effect of two different strength training methods on muscle strength, muscle mass, fat mass and endurance factors. Fourteen physical education students accepted to participate in this study. The participants were then randomly divided into three groups, traditional training group (TTG), cluster training group (CTG) and control group (CG). TTG consisted of 4 participants aged ( ± SD) (22.3 ± 1.5 years), body mass (79.2 ± 15.4 kg) and height (178.3 ± 11.9 cm). CTG consisted of 5 participants aged (22.2 ± 3.5 years), body mass (81.0 ± 24.0 kg) and height (180.2 ± 12.3 cm). CG consisted of 5 participants aged (22 ± 2.8 years), body mass (77 ± 19 kg) and height (174 ± 6.7 cm). The participants underwent a hypertrophy strength training program twice a week consisting of 4 sets of 10 reps at 70% of one-repetition maximum (1RM), using barbell squat and barbell bench press for 8 weeks. The CTG performed 2 x 5 reps using 10 s recovery in between repetitions and 50 s recovery between sets, while TTG performed 4 sets of 10 reps with 90 s recovery in between sets. Pre- and post-tests were administrated to assess body composition (weight, muscle mass, and fat mass), 1RM (bench press and barbell squat) and a laboratory endurance test (Bruce Protocol). Instruments used to collect the data were Tanita BC-601 scale (Tanita, Illinois, USA), Woodway treadmill (Woodway, Wisconsin, USA) and Vyntus CPX breath-to-breath system (Jaeger, Hoechberg, Germany). Analysis was conducted at all measured variables including time to peak VO2, peak VO2, heart rate (HR) at peak VO2, respiratory exchange ratio (RER) at peak VO2, and number of breaths per minute. The results indicate an increase in 1RM performance after 8 weeks of training. The change in 1RM squat was for the TTG = 30 ± 3.8 kg, CTG = 28.6 ± 8.3 kg and CG = 10.3 ± 13.8 kg. Similarly, the change in 1RM bench press was for the TTG = 9.8 ± 2.8 kg, CTG = 7.4 ± 3.4 kg and CG = 4.4 ± 3.4 kg. The within-group analysis from the oxygen consumption measured during the incremental exercise indicated that the TTG had only a statistical significant increase in their RER from 1.16 ± 0.04 to 1.23 ± 0.05 (P < 0.05). The CTG had a statistical significant improvement in their HR at peak VO2 from 186 ± 24 to 191 ± 12 Beats Per Minute (P < 0.05) and their RER at peak VO2 from 1.11 ± 0.06 to 1.18 ±0.05 (P < 0.05). Finally, the CG had only a statistical significant increase in their RER at peak VO2 from 1.11 ± 0.07 to 1.21 ± 0.05 (P < 0.05). The between-group analysis showed no statistical differences between all groups in all the measured variables from the oxygen consumption test during the incremental exercise including changes in muscle mass, fat mass, and weight (kg). The results indicate a similar effect of hypertrophy strength training irrespective of the methods of the training used on untrained subjects. Because there were no notable changes in body-composition measures, the results suggest that the improvements in performance observed in all groups is most probably due to neuro-muscular adaptation to training.

Keywords: hypertrophy strength training, cluster set, Bruce protocol, peak VO2

Procedia PDF Downloads 242
478 Induction Machine Design Method for Aerospace Starter/Generator Applications and Parametric FE Analysis

Authors: Wang Shuai, Su Rong, K. J.Tseng, V. Viswanathan, S. Ramakrishna

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The More-Electric-Aircraft concept in aircraft industry levies an increasing demand on the embedded starter/generators (ESG). The high-speed and high-temperature environment within an engine poses great challenges to the operation of such machines. In view of such challenges, squirrel cage induction machines (SCIM) have shown advantages due to its simple rotor structure, absence of temperature-sensitive components as well as low torque ripples etc. The tight operation constraints arising from typical ESG applications together with the detailed operation principles of SCIMs have been exploited to derive the mathematical interpretation of the ESG-SCIM design process. The resultant non-linear mathematical treatment yielded unique solution to the SCIM design problem for each configuration of pole pair number p, slots/pole/phase q and conductors/slot zq, easily implemented via loop patterns. It was also found that not all configurations led to feasible solutions and corresponding observations have been elaborated. The developed mathematical procedures also proved an effective framework for optimization among electromagnetic, thermal and mechanical aspects by allocating corresponding degree-of-freedom variables. Detailed 3D FEM analysis has been conducted to validate the resultant machine performance against design specifications. To obtain higher power ratings, electrical machines often have to increase the slot areas for accommodating more windings. Since the available space for embedding such machines inside an engine is usually short in length, axial air gap arrangement appears more appealing compared to its radial gap counterpart. The aforementioned approach has been adopted in case studies of designing series of AFIMs and RFIMs respectively with increasing power ratings. Following observations have been obtained. Under the strict rotor diameter limitation AFIM extended axially for the increased slot areas while RFIM expanded radially with the same axial length. Beyond certain power ratings AFIM led to long cylinder geometry while RFIM topology resulted in the desired short disk shape. Besides the different dimension growth patterns, AFIMs and RFIMs also exhibited dissimilar performance degradations regarding power factor, torque ripples as well as rated slip along with increased power ratings. Parametric response curves were plotted to better illustrate the above influences from increased power ratings. The case studies may provide a basic guideline that could assist potential users in making decisions between AFIM and RFIM for relevant applications.

Keywords: axial flux induction machine, electrical starter/generator, finite element analysis, squirrel cage induction machine

Procedia PDF Downloads 450
477 An Artificially Intelligent Teaching-Agent to Enhance Learning Interactions in Virtual Settings

Authors: Abdulwakeel B. Raji

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This paper introduces a concept of an intelligent virtual learning environment that involves communication between learners and an artificially intelligent teaching agent in an attempt to replicate classroom learning interactions. The benefits of this technology over current e-learning practices is that it creates a virtual classroom where real time adaptive learning interactions are made possible. This is a move away from the static learning practices currently being adopted by e-learning systems. Over the years, artificial intelligence has been applied to various fields, including and not limited to medicine, military applications, psychology, marketing etc. The purpose of e-learning applications is to ensure users are able to learn outside of the classroom, but a major limitation has been the inability to fully replicate classroom interactions between teacher and students. This study used comparative surveys to gain information and understanding of the current learning practices in Nigerian universities and how they compare to these practices compare to the use of a developed e-learning system. The study was conducted by attending several lectures and noting the interactions between lecturers and tutors and as an aftermath, a software has been developed that deploys the use of an artificial intelligent teaching-agent alongside an e-learning system to enhance user learning experience and attempt to create the similar learning interactions to those found in classroom and lecture hall settings. Dialogflow has been used to implement a teaching-agent, which has been developed using JSON, which serves as a virtual teacher. Course content has been created using HTML, CSS, PHP and JAVASCRIPT as a web-based application. This technology can run on handheld devices and Google based home technologies to give learners an access to the teaching agent at any time. This technology also implements the use of definite clause grammars and natural language processing to match user inputs and requests with defined rules to replicate learning interactions. This technology developed covers familiar classroom scenarios such as answering users’ questions, asking ‘do you understand’ at regular intervals and answering subsequent requests, taking advanced user queries to give feedbacks at other periods. This software technology uses deep learning techniques to learn user interactions and patterns to subsequently enhance user learning experience. A system testing has been undergone by undergraduate students in the UK and Nigeria on the course ‘Introduction to Database Development’. Test results and feedback from users shows that this study and developed software is a significant improvement on existing e-learning systems. Further experiments are to be run using the software with different students and more course contents.

Keywords: virtual learning, natural language processing, definite clause grammars, deep learning, artificial intelligence

Procedia PDF Downloads 126
476 Review of Carbon Materials: Application in Alternative Energy Sources and Catalysis

Authors: Marita Pigłowska, Beata Kurc, Maciej Galiński

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The application of carbon materials in the branches of the electrochemical industry shows an increasing tendency each year due to the many interesting properties they possess. These are, among others, a well-developed specific surface, porosity, high sorption capacity, good adsorption properties, low bulk density, electrical conductivity and chemical resistance. All these properties allow for their effective use, among others in supercapacitors, which can store electric charges of the order of 100 F due to carbon electrodes constituting the capacitor plates. Coals (including expanded graphite, carbon black, graphite carbon fibers, activated carbon) are commonly used in electrochemical methods of removing oil derivatives from water after tanker disasters, e.g. phenols and their derivatives by their electrochemical anodic oxidation. Phenol can occupy practically the entire surface of carbon material and leave the water clean of hydrophobic impurities. Regeneration of such electrodes is also not complicated, it is carried out by electrochemical methods consisting in unblocking the pores and reducing resistances, and thus their reactivation for subsequent adsorption processes. Graphite is commonly used as an anode material in lithium-ion cells, while due to the limited capacity it offers (372 mAh g-1), new solutions are sought that meet both capacitive, efficiency and economic criteria. Increasingly, biodegradable materials, green materials, biomass, waste (including agricultural waste) are used in order to reuse them and reduce greenhouse effects and, above all, to meet the biodegradability criterion necessary for the production of lithium-ion cells as chemical power sources. The most common of these materials are cellulose, starch, wheat, rice, and corn waste, e.g. from agricultural, paper and pharmaceutical production. Such products are subjected to appropriate treatments depending on the desired application (including chemical, thermal, electrochemical). Starch is a biodegradable polysaccharide that consists of polymeric units such as amylose and amylopectin that build an ordered (linear) and amorphous (branched) structure of the polymer. Carbon is also used as a catalyst. Elemental carbon has become available in many nano-structured forms representing the hybridization combinations found in the primary carbon allotropes, and the materials can be enriched with a large number of surface functional groups. There are many examples of catalytic applications of coal in the literature, but the development of this field has been hampered by the lack of a conceptual approach combining structure and function and a lack of understanding of material synthesis. In the context of catalytic applications, the integrity of carbon environmental management properties and parameters such as metal conductivity range and bond sequence management should be characterized. Such data, along with surface and textured information, can form the basis for the provision of network support services.

Keywords: carbon materials, catalysis, BET, capacitors, lithium ion cell

Procedia PDF Downloads 159
475 A Village Transformed as Census Town a Case Study of Village Nilpur, Tehsil Rajpura, District Patiala (Punjab, India)

Authors: Preetinder Kaur Randhawa

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The rural areas can be differentiated from urban areas in terms of their economic activities as rural areas are primarily involved in agricultural sector and provide natural resources whereas, urban areas are primarily involved in infrastructure sector and provide manufacturing services. Census of India defines a Census Town as an area which satisfies the following three criteria i.e. population exceeds 5000, at least 75 percent of male population engaged in non-agricultural sector and minimum population density of 400 persons per square kilometers. Urban areas can be attributed to the improvement of transport facilities, the massive decline in agricultural, especially male workers and workers shift to non-agricultural activities. This study examines the pattern, process of rural areas transformed into urban areas/ census town. The study has analyzed the various factors which are responsible for land transformation as well as the socio-economic transformation of the village population. Nilpur (CT) which belongs to Rajpura Tehsil in Patiala district, Punjab has been selected for the present study. The methodology adopted includes qualitative and quantitative research design, methods based on secondary data. Secondary data has been collected from unpublished revenue record office of Rajpura Tehsil and Primary Census Abstract of Patiala district, Census of India 2011. The results have showed that rate of transformation of a village to census town in Rajpura Tehsil has been one of highest among other villages. The census town has evolved through the evolutionary process of human settlement which grows in size, population and physical development. There must be a complete economic transformation and attainment of high level of technological development. Urban design and construction of buildings and infrastructure can be carried out better and faster and can be used to aid human habitation with the enhancement of quality of life. The study has concluded that in the selected area i.e Nilpur (CT) literacy rate has increased to 72.1 percent in year 2011 from 67.6 percent in year 2001. Similarly non-agricultural work force has increased to 95.2 percent in year 2011 from 81.1 percent in year 2001. It is very much clear that the increased literacy rate has put a positive impact on the involvement of non-agricultural workers have enhanced. The study has concluded that rural-urban linkages are important tools for understanding complexities of people livelihood and their strategies which involve mobility migration and the diversification of income sources and occupations.

Keywords: Census Town, India, Nilpur, Punjab

Procedia PDF Downloads 242
474 Multi-Criteria Selection and Improvement of Effective Design for Generating Power from Sea Waves

Authors: Khaled M. Khader, Mamdouh I. Elimy, Omayma A. Nada

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Sustainable development is the nominal goal of most countries at present. In general, fossil fuels are the development mainstay of most world countries. Regrettably, the fossil fuel consumption rate is very high, and the world is facing the problem of conventional fuels depletion soon. In addition, there are many problems of environmental pollution resulting from the emission of harmful gases and vapors during fuel burning. Thus, clean, renewable energy became the main concern of most countries for filling the gap between available energy resources and their growing needs. There are many renewable energy sources such as wind, solar and wave energy. Energy can be obtained from the motion of sea waves almost all the time. However, power generation from solar or wind energy is highly restricted to sunny periods or the availability of suitable wind speeds. Moreover, energy produced from sea wave motion is one of the cheapest types of clean energy. In addition, renewable energy usage of sea waves guarantees safe environmental conditions. Cheap electricity can be generated from wave energy using different systems such as oscillating bodies' system, pendulum gate system, ocean wave dragon system and oscillating water column device. In this paper, a multi-criteria model has been developed using Analytic Hierarchy Process (AHP) to support the decision of selecting the most effective system for generating power from sea waves. This paper provides a widespread overview of the different design alternatives for sea wave energy converter systems. The considered design alternatives have been evaluated using the developed AHP model. The multi-criteria assessment reveals that the off-shore Oscillating Water Column (OWC) system is the most appropriate system for generating power from sea waves. The OWC system consists of a suitable hollow chamber at the shore which is completely closed except at its base which has an open area for gathering moving sea waves. Sea wave's motion pushes the air up and down passing through a suitable well turbine for generating power. Improving the power generation capability of the OWC system is one of the main objectives of this research. After investigating the effect of some design modifications, it has been concluded that selecting the appropriate settings of some effective design parameters such as the number of layers of Wells turbine fans and the intermediate distance between the fans can result in significant improvements. Moreover, simple dynamic analysis of the Wells turbine is introduced. Furthermore, this paper strives for comparing the theoretical and experimental results of the built experimental prototype.

Keywords: renewable energy, oscillating water column, multi-criteria selection, Wells turbine

Procedia PDF Downloads 154
473 A Development of Practice Guidelines for Surgical Safety Management to Reduce Undesirable Incidents from Surgical Services in the Operating Room of Songkhla Hospital, Thailand

Authors: Thitima Plejai

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The practice in the operating room has been continually performed according to standards of services; however, undesirable incidents from surgical services are found such as surgical complications in the operating room. This participation action research aimed to develop practice guidelines for surgical safety management to reduce undesirable incidents from surgical services in the operating room of Songkhla Hospital. The target population was all 84 members of the multidisciplinary team who were involved in surgical services in the operating room consisting of 28 surgeons from five branches of surgery, 27 anesthetists and nurse anesthetists, and 29 surgical nurses. The data were collected through in-depth interviews, and non-participatory observations. The research instrument was tested by three experts, and the steps of the development consisted of four cycles, each consisting of assessment, planning, practice, practice reflection, and improvement until every step is practicable. The data were validated through triangulation research method, analyzed through content analysis and statistical analysis with number and percentage. The results of the development of practice guidelines surgical safety management to reduce undesirable incidents from surgical services could be concluded as follows. 1) The multidisciplinary team in surgery participated in the needs assessment for development of practice guidelines for surgical patient safety, and agreed on adapting the WHO Surgical Safety Checklists for use. 2) The WHO Surgical Safety Checklists was implemented, and meetings were held for the multidisciplinary team in surgery and the organizational risk committee to improve the practice guidelines to make them more practicable. 3) The multidisciplinary team consisting of surgeons from five branches of surgery, anesthetists, nurse anesthetists, surgical nurses, and the organizational risk committee announced policy on safety for surgical patients; the organizational risk committee designated the Surgical Safety Checklist as an instrument for surgical patient safety. The results of the safety management found that the surgical team members who could follow 100 percent of the guidelines were: professional nurses who checked patient identity and information before taking the patient to the operating room and kept complete records of data on the patients; surgical nurses who checked readiness of the patient before surgery; nurse anesthetists who assessed readiness before administering anesthetic drugs, and confirmed correctness of the patient; and circulating perioperative nurses who gave confirmation to the surgical team after completion of the surgery. The rates of undesirable incidents (surgical complications rates) before and after the implementation of the surgical safety management were 1.60 percent and 0.66 percent, respectively. The satisfaction of the surgery-related teams towards the use of the guidelines was 89 percent. The practice guidelines for surgical safety management to reduce undesirable incidents were taken as guidelines for surgical safety that the multidisciplinary team involved in the surgical process implemented correctly and in the same direction and clearly reduced undesirable incidents in surgical patients.

Keywords: practice guidelines, surgical safety management, reduce undesirable incidents, operating Room

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472 Burnout in the Resident Physician and a Simple Means of Improvement

Authors: Jacob Dangerfield, Jacob Pollard, Jennifer DeCou

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Introduction: Burnout, anxiety, and depression are three conditions that are prevalent in medical providers. This is especially the case in the field of anesthesia, which has a high number of providers suffering from burnout and burnout syndrome. A major contributor to this issue is isolation in the workplace, with a perceived lack of peer support as a major risk factor for burnout. Two organizational interventions that can be done to help improve this issue are small group sessions and providing affordable mental health services. Per American College of Graduate Medical Education (ACGME) Guidelines, these affordable mental health services are a requirement of all residency programs, but for a variety of reasons, many residents do not access them. As physicians, we are often not good at asking for help. With this in mind, we hypothesized that carrying out small group resiliency sessions facilitated by Graduate Medical Education (GME) Wellness Counselors would improve both resident peer support as well as the likelihood that a resident will reach out to GME Wellness in a time of need. Methods: We held small group resiliency sessions with the GME Wellness Mental Health Professionals during protected didactic time. These sessions were small groups, including the members of one’s class (i.e., first-year residents on their own), and were facilitated by 1-2 mental health professionals. After these sessions, we surveyed residents who attended using a short Google Forms survey and using a 5-point Likert Scale, asked residents about some outcomes from the session. A “strongly agree” or “agree” was considered a positive response. Results: Results from our survey showed that the resident sessions had multiple positive outcomes. This survey was sent to 29 residents, and we had a 62% response rate. We found out through this survey that these small group sessions had a perceived positive impact on resident personal well-being, increased perceived peer support from classmates, and made residents more likely to reach out to GME Wellness in the future. Perceived positive impact on well-being was found in 83% of resident respondents, improved perceived peer support in 83% of respondents, and 78% of resident respondents stated that this session increased their likelihood of reaching out to mental health professionals. Conclusions: Through this study, we can conclude that our hypothesis was correct in that Small Group Resiliency Sessions that are facilitated by GME Wellness Counselors improve both resident peer support as well as the likelihood a resident reaches out to these mental health professionals in time of need. We believe these findings are very important as they address two important factors that can aid in decreasing a provider’s risk of experiencing burnout. Through this simple means, we believe other residency programs can help the well-being of their residents, and together, we can decrease the number of cases of burnout in anesthesia.

Keywords: anesthesiology, burnout, wellness, depression, residents, trainees, mental health

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471 Assessment of Dietary Patterns of Saudi Patients with Type 2 Diabetes Mellitus in Ramadan and Non-Ramadan Periods

Authors: Abdullah S. Alghamdi, Khaled Alghamdi, Richard O. Jenkins, Parvez I. Haris

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Background: Unhealthy diet is one of the modifiable risk factors for developing type 2 diabetes mellitus (T2DM). Improvement in diet can be beneficial for countering diabetes. For example, HbA1c, an important biomarker for diabetes, can be reduced by 1.1% through only alteration in diet. Ramadan fasting has been reported to provide positive health benefits. However, optimal benefits are not achieved, often due to poor dietary habits and lifestyle. There is a need to better understand the dietary habits of people fasting during Ramadan, so that necessary improvements can be made to develop this form of fasting as a non-pharmacological strategy for management and prevention of T2DM. Aim: This study aimed to assess the dietary patterns of Saudi adult patients with T2DM over three different periods (before, during, and after Ramadan) and relate this to HbA1c levels. Methods: This study recruited 82 Saudi with T2DM, who chose to fast during Ramadan, from the Endocrine and Diabetic Centre of Al Iman General Hospital, Riyadh, Saudi Arabia. Ethical approvals for the study were obtained from De Montfort University and Saudi Ministry of Health. Dietary patterns were assessed by a self-administered questionnaire in each period. This assessment included the diet type and frequency. Blood samples were collected in each period for determination of HbA1c. Results: The number of meals per day for the participants significantly decreased during Ramadan (P < 0.001). The consumption of fruit and vegetables significantly increased during Ramadan (P = 0.017). However, the consumption of sugary drinks significantly increased during and after Ramadan (P = 0.005). Approximately 60% of the patients indicated that they ate sugary foods at least once per week. The consumption of bread and rice was reported to be at least two times per week. The consumption of rice significantly reduced during Ramadan (P = 0.002). The mean HbA1c significantly varied between periods (P = 0.001), with lowest level during Ramadan compared to before and after Ramadan. The increase in the consumption of fruits and vegetables had a medium effect size on the reduction in HbA1c during Ramadan. There was a variance of 7.7% in the mean difference in HbA1c levels between groups (who changed their fruit and vegetable consumption) which can be accounted for by the increase in the consumption of fruits and vegetables. Likewise, 9.3% of the variance in the mean HbA1c difference between the groups was accounted for by a decrease in the consumption of rice. Conclusion: The increase in the frequency of fruit and vegetables intake, and especially the reduction in the frequency of rice consumption, during Ramadan produce beneficial effects in reducing HbA1c level. Therefore, further improving the dietary habits of patients with T2DM, such as reducing their sugary drinks intake, may help them to obtain greater benefits from Ramadan fasting in the management of their diabetes. It is recommended that dietary guidance is provided to the public to maximise health benefits through Ramadan fasting.

Keywords: Diabetes, Diet, Fasting, HbA1c, Ramadan

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470 Innovative Technologies Functional Methods of Dental Research

Authors: Sergey N. Ermoliev, Margarita A. Belousova, Aida D. Goncharenko

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Application of the diagnostic complex of highly informative functional methods (electromyography, reodentography, laser Doppler flowmetry, reoperiodontography, vital computer capillaroscopy, optical tissue oximetry, laser fluorescence diagnosis) allows to perform a multifactorial analysis of the dental status and to prescribe complex etiopathogenetic treatment. Introduction. It is necessary to create a complex of innovative highly informative and safe functional diagnostic methods for improvement of the quality of patient treatment by the early detection of stomatologic diseases. The purpose of the present study was to investigate the etiology and pathogenesis of functional disorders identified in the pathology of hard tissue, dental pulp, periodontal, oral mucosa and chewing function, and the creation of new approaches to the diagnosis of dental diseases. Material and methods. 172 patients were examined. Density of hard tissues of the teeth and jaw bone was studied by intraoral ultrasonic densitometry (USD). Electromyographic activity of masticatory muscles was assessed by electromyography (EMG). Functional state of dental pulp vessels assessed by reodentography (RDG) and laser Doppler flowmetry (LDF). Reoperiodontography method (RPG) studied regional blood flow in the periodontal tissues. Microcirculatory vascular periodontal studied by vital computer capillaroscopy (VCC) and laser Doppler flowmetry (LDF). The metabolic level of the mucous membrane was determined by optical tissue oximetry (OTO) and laser fluorescence diagnosis (LFD). Results and discussion. The results obtained revealed changes in mineral density of hard tissues of the teeth and jaw bone, the bioelectric activity of masticatory muscles, regional blood flow and microcirculation in the dental pulp and periodontal tissues. LDF and OTO methods estimated fluctuations of saturation level and oxygen transport in microvasculature of periodontal tissues. With LFD identified changes in the concentration of enzymes (nicotinamide, flavins, lipofuscin, porphyrins) involved in metabolic processes Conclusion. Our preliminary results confirmed feasibility and safety the of intraoral ultrasound densitometry technique in the density of bone tissue of periodontium. Conclusion. Application of the diagnostic complex of above mentioned highly informative functional methods allows to perform a multifactorial analysis of the dental status and to prescribe complex etiopathogenetic treatment.

Keywords: electromyography (EMG), reodentography (RDG), laser Doppler flowmetry (LDF), reoperiodontography method (RPG), vital computer capillaroscopy (VCC), optical tissue oximetry (OTO), laser fluorescence diagnosis (LFD)

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469 The Effect of Positional Release Technique versus Kinesio Tape on Iliocostalis lumborum in Back Myofascial Pain Syndrome

Authors: Shams Khaled Abdelrahman Abdallah Elbaz, Alaa Aldeen Abd Al Hakeem Balbaa

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Purpose: The purpose of this study was to compare the effects of Positional Release Technique versus Kinesio Tape on pain level, pressure pain threshold level and functional disability in patients with back myofascial pain syndrome at iliocostalis lumborum. Backgrounds/significance: Myofascial Pain Syndrome is a common muscular pain syndrome that arises from trigger points which are hyperirritable, painful and tender points within a taut band of skeletal muscle. In more recent literature, about 75% of patients with musculoskeletal pain presenting to a community medical centres suffer from myofascial pain syndrome.Iliocostalis lumborum are most likely to develop active trigger points. Subjects: Thirty patients diagnosed as back myofascial pain syndrome with active trigger points in iliocostalis lumborum muscle bilaterally had participated in this study. Methods and materials: Patients were randomly distributed into two groups. The first group consisted of 15 patients (8 males and 7 females) with mean age 30.6 (±3.08) years, they received positional release technique which was applied 3 times per session, 3/week every other day for 2 weeks. The second group consisted of 15 patients(5 males, 10 females) with a mean age 30.4 (±3.35) years, they received kinesio tape which was applied and changed every 3 days with one day off for a total 3 times in 2 weeks. Both techniques were applied over trigger points of the iliocostalis lumborum bilaterally. Patients were evaluated pretreatment and posttreatment program for Pain intensity (Visual analogue scale), pressure pain threshold (digital pressure algometry), and functional disability (The Oswestry Disability Index). Analyses: Repeated measures MANOVA was used to detect differences within and between groups pre and post treatment. Then the univariate ANOVA test was conducted for the analysis of each dependant variable within and between groups. All statistical analyses were done using SPSS. with significance level set at p<0.05 throughout all analyses. Results: The results revealed that there was no significant difference between positional release technique and kinesio tape technique on pain level, pressure pain threshold and functional activities (p > 0.05). Both groups of patients showed significant improvement in all the measured variables (p < 0.05) evident by significant reduction of both pain intensity and functional disability as well as significant increase of pressure pain threshold Conclusions : Both positional release technique and kinesio taping technique are effective in reducing pain level, improving pressure pain threshold and improving function in treating patients who suffering from back myofascial pain syndrome at iliocostalis lumborum. As there was no statistically significant difference was proven between both of them.

Keywords: positional release technique, kinesio tape, myofascial pain syndrome, Iliocostalis lumborum

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468 Use of Locomotor Activity of Rainbow Trout Juveniles in Identifying Sublethal Concentrations of Landfill Leachate

Authors: Tomas Makaras, Gintaras Svecevičius

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Landfill waste is a common problem as it has an economic and environmental impact even if it is closed. Landfill waste contains a high density of various persistent compounds such as heavy metals, organic and inorganic materials. As persistent compounds are slowly-degradable or even non-degradable in the environment, they often produce sublethal or even lethal effects on aquatic organisms. The aims of the present study were to estimate sublethal effects of the Kairiai landfill (WGS: 55°55‘46.74“, 23°23‘28.4“) leachate on the locomotor activity of rainbow trout Oncorhynchus mykiss juveniles using the original system package developed in our laboratory for automated monitoring, recording and analysis of aquatic organisms’ activity, and to determine patterns of fish behavioral response to sublethal effects of leachate. Four different concentrations of leachate were chosen: 0.125; 0.25; 0.5 and 1.0 mL/L (0.0025; 0.005; 0.01 and 0.002 as part of 96-hour LC50, respectively). Locomotor activity was measured after 5, 10 and 30 minutes of exposure during 1-minute test-periods of each fish (7 fish per treatment). The threshold-effect-concentration amounted to 0.18 mL/L (0.0036 parts of 96-hour LC50). This concentration was found to be even 2.8-fold lower than the concentration generally assumed to be “safe” for fish. At higher concentrations, the landfill leachate solution elicited behavioral response of test fish to sublethal levels of pollutants. The ability of the rainbow trout to detect and avoid contaminants occurred after 5 minutes of exposure. The intensity of locomotor activity reached a peak within 10 minutes, evidently decreasing after 30 minutes. This could be explained by the physiological and biochemical adaptation of fish to altered environmental conditions. It has been established that the locomotor activity of juvenile trout depends on leachate concentration and exposure duration. Modeling of these parameters showed that the activity of juveniles increased at higher leachate concentrations, but slightly decreased with the increasing exposure duration. Experiment results confirm that the behavior of rainbow trout juveniles is a sensitive and rapid biomarker that can be used in combination with the system for fish behavior monitoring, registration and analysis to determine sublethal concentrations of pollutants in ambient water. Further research should be focused on software improvement aimed to include more parameters of aquatic organisms’ behavior and to investigate the most rapid and appropriate behavioral responses in different species. In practice, this study could be the basis for the development and creation of biological early-warning systems (BEWS).

Keywords: fish behavior biomarker, landfill leachate, locomotor activity, rainbow trout juveniles, sublethal effects

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