Search results for: briquetting reduction

Authors: H. Aripin, I. Made Joni, Edvin Priatna, Nundang Busaeri, Svilen Sabchevski

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In this investigation, manganese has been produced from medium grade manganese ore from Karangnunggal mine (West Java, Indonesia). The ores were grinded using a jar mill to pass through a 150 mesh sieve. The effects of keeping it at a temperature of 1200 °C in methane gas on the structural properties have been studied. The material’s properties have been characterized on the basis of the experimental data obtained using X-ray fluorescence (XRF), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. It has been found that the ore contains MnO₂ as the main constituents at about 46.80 wt.%. It can be also observed that the ore particles are agglomerated forming dense grains with different texture and morphology. The irregular-shaped grains with dark contrast, the large brighter grains, and smaller grains with bright texture and smooth surfaces are associated with the presence of manganese, calcium, and quartz, respectively. From XRD patterns, MnO₂ is reduced to hausmannite (Mn₃O₄), manganosite (MnO) and manganese carbide (Mn₇C₃). At a temperature of 1200°C the keeping time does not have any effect on the formation of crystals and the crystalline phases remain almost unchanged in the time range from 15 to 90 minutes. An increase of the keeping time up to 45 minutes during the sintering process leads to an increase of the MnO concentration, while at 90 minutes, the concentration decreases. At longer keeping times the excess reaction of the methane gas and manganese oxide in the ore causes an increase of carbon deposition. As a result, it blocks the particle surface and then hinders the reduction process of manganese oxide. From FTIR spectrum allows one to explain that the appearance of C=O stretching mode arises from absorption of atmospheric methane and manganese oxide of the ore. The intensity of this band increases with increasing the keeping time, indicating an increase of carbon deposition on the surface of manganese oxide.

Keywords: manganese, medium grade manganese ore, structural properties, keeping the temperature, carbon deposition

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Authors: Abeer F. Almarzouki, Christopher A. Brown, Richard J. Brown, Anthony K. P. Jones

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Although relief is commonly assumed to be a direct reflection of pain reduction, it seems to be driven by complex emotional interactions in which pain reduction is only one component. For example, termination of a painful/aversive event may be relieving and rewarding. Accordingly, in this study, whether terminating an aversive negative prediction of pain would be reflected in a greater relief experience was investigated, with a view to separating apart the effects of the manipulation on pain and relief. We use aversive conditioning paradigm to investigate the perception of relief in an aversive (threat) vs. positive context. Participants received positive predictors of a non-painful outcome which were presented within either a congruent positive (non-painful) context or an incongruent threat (painful) context that had been previously conditioned; trials followed by identical laser stimuli on both conditions. Participants were asked to rate the perceived intensity of pain as well as their perception of relief in response to the cue predicting the outcome. Results demonstrated that participants reported more pain in the aversive context compared to the positive context. Conversely, participants reported more relief in the aversive context compares to the neutral context. The rating of relief in the threat context was not correlated with pain reports. The results suggest that relief is not dependant on pain intensity. Consistent with this, relief in the threat context was greater than that in the positive expectancy condition, while the opposite pattern was obtained for the pain ratings. The value of relief in this study is better appreciated in the context of an impending negative threat, which is apparent in the higher pain ratings in the prior negative expectancy compared to the positive expectancy condition. Moreover, the more threatening the context (as manifested by higher unpleasantness/higher state anxiety scores), the more the relief is appreciated. The importance of the study highlights the importance of exploring relief and pain intensity in monitoring separately or evaluating pain-related suffering. The results also illustrate that the perception of painful input may largely be shaped by the context and not necessarily stimulus-related.

Keywords: aversive context, pain, predictions, relief

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Authors: Omnia M.Kandil, Noha M. F. Hassan, Doaa Sedky, Hatem A. Shalaby, Heba M. Ashry, Nadia M. T. Abu El Ezz, Sahar M. Kandeel, Mohamed S. Abdelfattah Ying L, Ebtesam M. Al-Olayan

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The cestode, Taenia saginata is a zoonotic tapeworm that it’s larval stage which known as Cysticercus bovis cause cyst formation in cattle’s organs such as heart, lung, liver, tongue, esophagus and diaphragm muscle, despite the infected cattle may show no clinical signs. In view of considerable interest in developing cysticidal drugs including those from medicinal plants, because of their consideration as eco-friendly and biodegradable as well as having multiple bioactive compounds that may translate to multiple mechanisms in killing the parasites. This study was achieved to evaluate, for the first time, the efficacy of methanolic extract of Balanites aegyptiaca fruits and Moringa oleifera seeds against metacestode larval stage of the cestode Taenia saginata in BALB/c mice compared with commonly used anthelmintic albendazole and assigning the level of tumor necrosis factor (TNF-α) to monitor immune and inflammatory response of experimentally infected animals. The results revealed a marked decrease in the numbers of cysticerci found in all treated mice groups and up to 88% reduction was achieved in the B. aegyptiaca treated group; higher than that was recorded in both M. oleifera (72.23%) and albendazole treated ones (80.56%). The cysts of the treated groups were smaller of the control one. Besides, the mean concentration of TNF-α following treatment with Balanites and Moringa extracts, was higher but not significant difference than that in the untreated infected control one (P<0.05), evidence for inflammation and cyst damage. It can be concluded that the in vivo efficacy of M. oleifera extract was comparable to a commercial anthelmintic, and the B. aegyptiaca extract was superior in the reduction of cysticerci numbers.

Keywords: Balanites aeggyptica, Moringa oleifera, cysticercosis, BALB/C mice

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Authors: N. Noori, P. Taherkhani, A. Akhondzadeh Basti, H. Gandomi, M. Alimohammadi

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Research on natural antimicrobial agents, especially of plant origin, highly noticed in recent years and evaluation of antimicrobial effects of native plants such as Bunium persicum Boiss. is especially important. In the present study, sensory characteristics and microbiological properties of Gouda cheese affected by different concentrations of Bunium persicum Boiss. essential oil were investigated. Extraction of the essential oil was performed by hydro distillation. The oil was analyzed by GC using flame ionization (FID) and GC/ MS for detection. The antimicrobial effects were determined against various microbial groups (aerobic mesophilic bacteria, enterococci, mesophilic lactobacilli, enterobacteriaceae, lactococcus and yeasts). Microbial groups were counted during ripening period using plate count on specific culture media. Organoleptic evaluation including teture, flavor, odor, color and total acceptability were determined at the end of aging. According to results, the essential oil yield was 4/1 % ( W/ W). Twenty- six compounds were identified in the oil that concluded 99.7 % of the total oil. The major components of Bunium persicum Boiss. essential oil were γ- terpinene- 7- al (26.9 %) and cuminaldehyde (23.3 %). Generally, the increase of Black Cumin essential oil concentration led to reduction in microbial counts in different groups. The maximum antimicrobial effect was seen in yeast that reduced by 2 log compared to the control group at EO concentration of 4µl/ ml at day 90.The minimum reduction was observed in enterobacteriaceae that showed only 0.75 log decreese compared to the control at the same concentration of EO. Addition of EO improved organoleptic properties of Gouda cheese especially in the case of flavor and odor characteristic. However, no significant differences were observed in texture and color between treatment and control groups. Bunium persicum Boiss. essential oil could be used as preservative material and flavoring agent in some kinds of food such as cheese and also could be provided consumers health.

Keywords: Bunium persicum Boiss. essential oil, Microbiological properties, sensory evaluation, gouda cheese

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Authors: Mahshid Davoodpoor, Zahra Shamohammadi Ghahsareh, Saeid Razfar, Alaleh Dabbaghi

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Nowadays, air pollution has become a topic of great concern all over the world. One of the main sources of air pollution is automobile exhaust gas, which introduces a large number of toxic gases, including CO, unburned hydrocarbons (HCs), NOx, and non-methane hydrocarbons (NMHCs), into the air. The application of three-way catalysts (TWCs) is still the most effective strategy to mitigate the emission of these pollutants. Due to the stringent environmental regulations which continuously become stricter, studies on the TWCs are ongoing despite several years of research and development. This arises from the washcoat complexity and the several numbers of parameters involved in the redox reactions. The main objectives of these studies are the optimization of washcoat formulation and the investigation of different coating modes. Perovskite (ABO₃), as a promising class of materials, has unique features that make it versatile to use as an alternative to commonly mixed oxides in washcoats. High catalytic activity for oxidation reactions and its relatively high oxygen storage capacity are important properties of perovskites in catalytic applications. Herein, La₀.₈Ba₀.₂FeO₃ perovskite material was synthesized using the co-precipitation method and characterized by XRD, ICP, and BET analysis. The effect of synthesis conditions, including B site metal (Fe and Co), metal precursor concentration, and dopant (Ba), were examined on the phase purity of the products. The selected perovskite sample was used as one of the components in the TWC formulation to evaluate its catalytic performance through Light-off, oxygen storage capacity, and emission analysis. Results showed a remarkable increment in oxygen storage capacity and also revealed that T50 and emission of CO, HC, and NOx reduced in the presence of perovskite structure which approves the enhancement of catalytic performance for the new washcoat formulation. This study shows the brilliant future of advanced oxide structures in the TWCs.

Keywords: Perovskite, three-way catalyst, PGMs, PGMs reduction

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Authors: Taha Anjamrooz, Sareh Rajabi, Ayman Alzaatreh

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Smart cities are playing important roles in real life. Integration and automation between different features of modern cities and information technologies improve smart city efficiency, energy management, human and equipment resource management, life quality and better utilization of resources for the customers. One of difficulties in this path, is use, interface and link between software, hardware, and other IT technologies to develop and optimize processes in various business fields such as construction, supply chain management and transportation in parallel to cost-effective and resource reduction impacts. Also, Smart cities are certainly intended to demonstrate a vital role in offering a sustainable and efficient model for smart houses while mitigating environmental and ecological matters. Energy management is one of the most important matters within smart houses in the smart cities and communities, because of the sensitivity of energy systems, reduction in energy wastage and maximization in utilizing the required energy. Specially, the consumption of energy in the smart houses is important and considerable in the economic balance and energy management in smart city as it causes significant increment in energy-saving and energy-wastage reduction. This research paper develops features and concept of smart city in term of overall efficiency through various effective variables. The selected variables and observations are analyzed through data analysis processes to demonstrate the efficiency of smart city and compare the effectiveness of each variable. There are ten chosen variables in this study to improve overall efficiency of smart city through increasing effectiveness of smart houses using an automated solar photovoltaic system, RFID System, smart meter and other major elements by interfacing between software and hardware devices as well as IT technologies. Secondly to enhance aspect of energy management by energy-saving within smart house through efficient variables. The main objective of smart city and smart houses is to reproduce energy and increase its efficiency through selected variables with a comfortable and harmless atmosphere for the customers within a smart city in combination of control over the energy consumption in smart house using developed IT technologies. Initially the comparison between traditional housing and smart city samples is conducted to indicate more efficient system. Moreover, the main variables involved in measuring overall efficiency of system are analyzed through various processes to identify and prioritize the variables in accordance to their influence over the model. The result analysis of this model can be used as comparison and benchmarking with traditional life style to demonstrate the privileges of smart cities. Furthermore, due to expensive and expected shortage of natural resources in near future, insufficient and developed research study in the region, and available potential due to climate and governmental vision, the result and analysis of this study can be used as key indicator to select most effective variables or devices during construction phase and design

Keywords: smart city, traditional housing, RFID, photovoltaic system, energy efficiency, energy saving

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Authors: Ekele T. Ochedi, Ahmad H. Taki, Birgit Painter

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The effect of the sun and its path on thermal comfort and energy consumption in residential buildings in tropical climates constitute a serious concern for designers, building owners, and users. Passive design approaches based on the sun and its path have been identified as a means of reducing energy consumption as well as enhancing thermal comfort in buildings worldwide. Hence, a thorough understanding regarding the sun path is key to achieving this. This is necessary due to energy need, poor energy supply, and distribution, energy poverty, and over-dependence on electric generators for power supply in Nigeria. These challenges call for a change in the approach to energy-related issues, especially in terms of buildings. The aim of this study is to explore the influence of building orientation, glazing and the use of shading devices on residential buildings in Nigeria. This is intended to provide data that will guide designers in the design of energy-efficient residential buildings. The paper used EnergyPlus to analyze a typical semi-detached residential building in Lokoja, Nigeria using hourly weather data for a period of 10 years. Building performance was studied as well as possible improvement regarding different orientations, glazing types and shading devices. The simulation results show some reductions in energy consumption in response to changes in building orientation, types of glazing and the use of shading devices. The results indicate 29.45% reduction in solar gains and 1.90% in annual operative temperature using natural ventilation only. This shows a huge potential to reduce energy consumption and improve people’s well-being through the use of proper building orientation, glazing and appropriate shading devices on building envelope. The study concludes that for a significant reduction in total energy consumption by residential buildings, the design should focus on multiple design options rather than concentrating on one or few building elements. Moreover, the investigation confirms that energy performance modeling can be used by building designers to take advantage of the sun and to evaluate various design options.

Keywords: energy consumption, energy-efficient buildings, glazing, thermal comfort, shading devices, solar gains

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Authors: Maryam Siyami

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Zero energy buildings refer to buildings that have zero annual energy consumption and do not produce carbon emissions. In today's world, considering the limited resources of fossil fuels, buildings, industries and other organizations have moved towards using other available energies. The idea and principle of net zero energy consumption has attracted a lot of attention because the use of renewable energy is a means and a solution to eliminate pollutants and greenhouse gases. Due to the increase in the cost of fossil fuels and their destructive effects on the environment and disrupting the ecological balance, today the plans related to zero energy principles have become very practical and have gained particular popularity. In this research, building modeling has been done in the Design Builder software environment. Based on the changes in the required energy throughout the year in different roof thickness conditions, it has been observed that with the increase in roof thickness, the amount of heating energy required has a downward trend, from 6730 kilowatt hours in the roof thickness of 10 cm to 6408 kilowatt hours in the roof thickness condition. 20 cm is reached, which represents a reduction of about 4.7% in energy if the roof thickness is doubled. Also, with the increase in the thickness of the roof throughout the year, the amount of cooling energy required has a gentle downward trend and has reached from 4964 kilowatt hours in the case of a roof thickness of 10 cm to 4859 kilowatt hours in the case of a roof thickness of 20 cm, which is a decrease equal to It displays 2%. It can be seen that the trend of changes in the energy required for cooling and heating is not much affected by the thickness of the roof (with an effect of 98%) and therefore there is no technical and economic recommendation to increase the thickness of the roof in this sector. Finally, based on the changes in the carbon dioxide produced in different states of the roof thickness, it has been observed that with the increase in the roof thickness, energy consumption and consequently the production of carbon dioxide has decreased. By increasing the thickness of the roof from 10 cm to 20 cm, the amount of carbon dioxide produced by heating the building has decreased by 27%. Also, this amount of reduction has been obtained based on the cooling system and for different amounts of roof thickness equal to 19%.

Keywords: energy consumption, green building, design builder, AHP

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Authors: Carlos Riascos, Peter Thomson

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Real-time hybrid simulation (RTHS) is a modern cyber-physical technique used for the experimental evaluation of complex systems, that treats the system components with predictable behavior as a numerical substructure and the components that are difficult to model as an experimental substructure. Therefore it is an attractive method for evaluation of the response of civil structures under earthquake, wind and anthropic loads. Another practical application of RTHS is the evaluation of control systems, as these devices are often nonlinear and their characterization is an important step in the design of controllers with the desired performance. In this paper, the response of three-story shear frame controlled by a tuned liquid column damper (TLCD) and subject to base excitation is considered. Both passive and semi-active control strategies were implemented and are compared. While the passive TLCD achieved a reduction of 50% in the acceleration response of the main structure in comparison with the structure without control, the semi-active TLCD achieved a reduction of 70%, and was robust to variations in the dynamic properties of the main structure. In addition, a RTHS was implemented with the main structure modeled as a linear, time-invariant (LTI) system through a state space representation and the TLCD, with both control strategies, was evaluated on a shake table that reproduced the displacement of the virtual structure. Current assessment measures for RTHS were used to quantify the performance with parameters such as generalized amplitude, equivalent time delay between the target and measured displacement of the shake table, and energy error using the measured force, and prove that the RTHS described in this paper is an accurate method for the experimental evaluation of structural control systems.

Keywords: structural control, hybrid simulation, tuned liquid column damper, semi-active sontrol strategy

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Authors: Ines Raies, Eric Kohler, Marc Fleury, Béatrice Ledésert

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In this work, the impact of clay minerals on the formation damage of sandstone reservoirs is studied to provide a better understanding of the problem of deep geothermal reservoir permeability reduction due to fine particle dispersion and migration. In some situations, despite the presence of filters in the geothermal loop at the surface, particles smaller than the filter size (<1 µm) may surprisingly generate significant permeability reduction affecting in the long term the overall performance of the geothermal system. Our study is carried out on cores from a Triassic reservoir in the Paris Basin (Feigneux, 60 km Northeast of Paris). Our goal is to first identify the clays responsible for clogging, a mineralogical characterization of these natural samples was carried out by coupling X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The results show that the studied stratigraphic interval contains mostly illite and chlorite particles. Moreover, the spatial arrangement of the clays in the rocks as well as the morphology and size of the particles, suggest that illite is more easily mobilized than chlorite by the flow in the pore network. Thus, based on these results, illite particles were prepared and used in core flooding in order to better understand the factors leading to the aggregation and deposition of this type of clay particles in geothermal reservoirs under various physicochemical and hydrodynamic conditions. First, the stability of illite suspensions under geothermal conditions has been investigated using different characterization techniques, including Dynamic Light Scattering (DLS) and Scanning Transmission Electron Microscopy (STEM). Various parameters such as the hydrodynamic radius (around 100 nm), the morphology and surface area of aggregates were measured. Then, core-flooding experiments were carried out using sand columns to mimic the permeability decline due to the injection of illite-containing fluids in sandstone reservoirs. In particular, the effects of ionic strength, temperature, particle concentration and flow rate of the injected fluid were investigated. When the ionic strength increases, a permeability decline of more than a factor of 2 could be observed for pore velocities representative of in-situ conditions. Further details of the retention of particles in the columns were obtained from Magnetic Resonance Imaging and X-ray Tomography techniques, showing that the particle deposition is nonuniform along the column. It is clearly shown that very fine particles as small as 100 nm can generate significant permeability reduction under specific conditions in high permeability porous media representative of the Triassic reservoirs of the Paris basin. These retention mechanisms are explained in the general framework of the DLVO theory

Keywords: geothermal energy, reinjection, clays, colloids, retention, porosity, permeability decline, clogging, characterization, XRD, SEM-EDS, STEM, DLS, NMR, core flooding experiments

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Authors: Muhammad Irfan, Guillermo Requena, Jan Haubrich

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Adhesively bonded aluminum joints are common in automotive and aircraft industries and are one of the enablers of lightweight construction to minimize the carbon emissions during transportation for a sustainable life. This study is focused on the effects of two thermal processing routes, i.e., by direct and induction heating, and their parameters on void formation in PA6 bonded aluminum EN-AW6082 joints. The joints were characterized microanalytically as well as by lap shear experiments. The aging resistance of the joints was studied by accelerated aging tests at 80°C hot water. It was found that the processing of single lap joints by direct heating in a convection oven causes the formation of a large number of voids in the bond line. The formation of voids in the convection oven was due to longer processing times and was independent of any surface pretreatments of the metal as well as the processing temperature. However, when processing at low temperatures, a large number of small-sized voids were observed under the optical microscope, and they were larger in size but reduced in numbers at higher temperatures. An induction heating process was developed, which not only successfully reduced or eliminated the voids in PA6 bonded joints but also reduced the processing times for joining significantly. Consistent with the trend in direct heating, longer processing times and higher temperatures in induction heating also led to an increased formation of voids in the bond line. Subsequent single lap shear tests revealed that the increasing void contents led to a 21% reduction in lap shear strengths (i.e., from ~47 MPa for induction heating to ~37 MPa for direct heating). Also, there was a 17% reduction in lap shear strengths when the consolidation temperature was raised from 220˚C to 300˚C during induction heating. However, below a certain threshold of void contents, there was no observable effect on the lap shear strengths as well as on hydrothermal aging resistance of the joints consolidated by the induction heating process.

Keywords: adhesive, aluminium, convection oven, induction heating, mechanical properties, nylon6 (PA6), pretreatment, void

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Authors: M. Kuzhko, M. Gumeniuk, D. Butov, T. Tlustova, O. Denysov, T. Sprynsian

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Abstract: The objective of this work was to study the efficacy and safety of inhaled nebulized chemotherapy in the treatment of patients with newly diagnosed pulmonary tuberculosis in comparison with standard antimycobacterial therapy. Materials and methods: The study involved 68 patients aged between 20 and 70 years with newly diagnosed pulmonary tuberculosis. Patients were allocated to two groups. The first (main, n=21) group of patients received standard chemotherapy and further 0.15 g of isoniazid and rifampicin 0.15 g inhaled through a nebulizer, also they received salmeterol 50 mcg + fluticasone propionate 250 mcg at 2 breaths twice a day for 2 months. The second (control, n=47) group of patients received standard chemotherapy, consisting of orally administered isoniazid (0.3 g), rifampicin (0.6 g), pyrazinamide (2 g), ethambutol (1.2 g) with a dose reduction after the intensive phase of the therapy. The anti-TB drugs were procured through the Ukraine’s centralized national supply system. Results: Intoxication symptoms in the first group reduced following 1.39±0.18 months, whereas in the second group, intoxication symptoms reduced following 2.7±0.1 months, p<.001. Moreover, respiratory symptoms regression in the first group was observed following 1.6±0.2 months, whereas in the second group – following 2.5±0.2 months, p<0.05. Bacillary excretion period evaluated within 1 month was reduced, as it was shown by 66.6±10.5% in the main group compared to 27.6±6.5%, p<0.05, in the control group. In addition, period of cavities healing was reduced to 2.9±0.2 months in the main group compared to 3.7±0.1 months, p<0.05, in the control group. Residual radiological lung damage findings (large residual changes) were observed in 22 (23.8±9.5 %) patients of the main group versus 24 (51.0±7.2 %) patients in the control group, p<0.05. After completion of treatment scar stenosis of the bronchi II-III art. diagnosed in 3 (14.2±7.8%) patients in main group and 17 (68.0±6.8%) - control group, p<0.05. The duration of hospital treatment was 2.4±0.4 months in main group and 4.1±0.4 months in control group, p<0.05. Conclusion: Administration of of inhaled nebulized chemotherapy in patients with newly diagnosed pulmonary tuberculosis resulted in a comparatively quick reduction of disease manifestation.

Keywords: inhaled nebulized chemotherapy, pulmonary tuberculosis, tuberculosis, treatment of tuberculosis

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Authors: Samih Ahmed, Guayente Minchot, Fritz King, Mikael Hallgren

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The stress ribbon system has numerous advantages that include but are not limited to increasing overall stiffness, control deflections, and reduction of materials consumption, which in turn, reduces the load and the cost. Nevertheless, its use is usually limited to bridges, in particular, pedestrian bridges; this can be attributed to the insufficient space that buildings' usually have for end supports, and/or back- stayed cables, that can accommodate the expected high pull-out forces occurring at the cables' ends. In this work, the roof of Västerås Travel Center, which will become one of the longest cable suspended roofs in the world, was chosen as a case study. The aim was to investigate the optimal technique to model the post-tensioned stress ribbon system for the roof structure using the FEM software SAP2000 and to assess any possible reduction in the pull-out forces, deflections, and concrete stresses. Subsequently, a conventional cable suspended roof was simulated using SAP2000, and compared to the post-tension stress ribbon system in order to examine the potential of the latter. Moreover, the effects of temperature loads and support movements on the final design loads were examined. Based on the study, a few practical recommendations concerning the construction method and the iterative design process, required to meet the architectural geometrical demands, are stated by the authors. The results showed that the post-tensioned stress ribbon system reduces the concrete stresses, overall deflections, and more importantly, reduces the pull-out forces and the vertical reactions at both ends by up to 16% and 11%, respectively, which substantially reduces the design forces for the support structures. The magnitude of these reductions was found to be highly correlated to the applied prestressing force, making the size of the prestressing force a key factor in the design.

Keywords: cable suspended, post-tension, roof structure, SAP2000, stress ribbon

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Authors: Marriette Sakah, Samuel Gyamfi, Morkporkpor Delight Sedzro, Christoph Kuhn

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Ghana is experiencing rapid economic development and its cities command an increasingly dominant role as centers of both production and consumption. Cities run on energy and are extremely vulnerable to energy scarcity, energy price escalations and health impacts of very poor air quality. The overriding concern in Ghana and other West African states is bridging the gap between energy demand and supply. Energy efficiency presents a cost-effective solution for supply challenges by enabling more coverage with current power supply levels and reducing the need for investment in additional generation capacity and grid infrastructure. In Ghana, major issues for energy policy formulation in residential applications include lack of disaggregated electrical energy consumption data and lack of thorough understanding with regards to socio-economic influences on energy efficiency investment. This study uses a bottom up approach to estimate baseline electricity end-use as well as the energy consumption of best available technologies to enable estimation of energy-efficiency resource in terms of relative reduction in total energy use for Tema city, Ghana. A ground survey was conducted to assess the probable consumer behavior in response to energy efficiency initiatives to enable estimation of the amount of savings that would occur in response to specific policy interventions with regards to funding and incentives provision targeted at households. Results show that 16% - 54% reduction in annual electricity consumption is reasonably achievable depending on the level of incentives provision. The saved energy could supply 10000 - 34000 additional households if the added households use only best available technology. Political support and consumer awareness are necessary to translate energy efficiency resources into real energy savings.

Keywords: achievable energy savings, energy efficiency, Ghana, household appliances

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Authors: S. Korkut, M. S. Kilic, E. Erhan

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In order to detect and quantify the phenolic contents of a wastewater with biosensors, two working electrodes based on modified Poly (Pyrrole) films were fabricated. Enzyme horseradish peroxidase was used as biomolecule of the prepared electrodes. Various phenolics were tested at the biosensor. Phenol detection was realized by electrochemical reduction of quinones produced by enzymatic activity. Analytical parameters were calculated and the results were compared with each other.

Keywords: carbon nanotube, phenol biosensor, polypyrrole, poly (glutaraldehyde)

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Authors: Yeganeh Attari, Gudmund Reidar Eiksund, Hans Peter Jostad

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In Geotechnical practice, there is no standard method recognized by the industry to account for the reduction of safety factor of a slope as an effect of soil displacement and pore pressure build-up during pile installation. Pile driving disturbs causes large strains and generates excess pore pressures in a zone that can extend many diameters from the installed pile, resulting in a decrease of the shear strength of the surrounding soil. This phenomenon may cause slope failure. Moreover, dissipation of excess pore pressure set-up may cause weakening of areas outside the volume of soil remoulded during installation. Because of complex interactions between changes in mean stress and shearing, it is challenging to predict installation induced pore pressure response. Furthermore, it is a complex task to follow the rate and path of pore pressure dissipation in order to analyze slope stability. In cohesive soils it is necessary to implement soil models that account for strain softening in the analysis. In the literature, several cases of slope failure due to pile driving activities have been reported, for instance, a landslide in Gothenburg that resulted in a slope failure destroying more than thirty houses and Rigaud landslide in Quebec which resulted in loss of life. Up to now, several methods have been suggested to predict the effect of pile driving on total and effective stress, pore pressure changes and their effect on soil strength. However, this is still not well understood or agreed upon. In Norway, general approaches applied by geotechnical engineers for this problem are based on old empirical methods with little accurate theoretical background. While the limitations of such methods are discussed, this paper attempts to capture the reduction in the factor of safety of a slope during pile driving, using coupled Finite Element analysis and cavity expansion method. This is demonstrated by analyzing a case of slope failure due to pile driving in Norway.

Keywords: cavity expansion method, excess pore pressure, pile driving, slope failure

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Authors: Sruthi Ramagiri, Rajeev T.

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Free radical damage has been entailed as the major culprit in the ischemic stroke contributing for oxidative damage. Recent investigations on Hydroxy Safflower Yellow A (HSYA) suggested its role in cerebral ischemia and various neurodegenerative disorders with unidentified molecular mechanisms. The current study was designed to investigate putative therapeutic role and possible molecular mechanisms of HSYA administration during the onset of reperfusion in cerebral ischemia-reperfusion (I/R) injury in cerebral stroke. Cerebral stroke was achieved by focal ischemic model. HSYA (10 mg/kg) was injected intravenously via the tail vein 5 minutes before reperfusion. Losses of sensorimotor abilities were evaluated by neurological scoring, spontaneous locomotor activity, and rotarod performance. Extent of oxidative stress was evaluated by biochemical parameters i.e., malondialdehyde (MDA), Glutathione (GSH), Super Oxide Dismutase (SOD) and catalase levels. The infarct volume of brain was assessed by 2,3,5-triphenyl tetrazolium chloride (TTC) staining technique. Increased cerebral injury (I/R) was evidenced by motor impairment, increased infarct volume and elevation of MDA levels along with significant reduction in antioxidant i.e.,MDA levels along with significant reduction in antioxidant i.e., GSH, SOD and catalase levels when compared to sham control. However, post conditioning with HSYA (10 mg/kg, i.v.) at the onset of reperfusion has significantly ameliorated sensorimotor abilities, attenuated MDA levels and reduced the infarct volume as compared with vehicle treated I/R injury group. Moreover, HSYA treatments improved antioxidant enzyme levels as compared with vehicle treated I/R-injury group. In conclusion, it may be suggested that HSYA post conditioning could be novel therapeutic approach against I/R injury in cerebral stroke possibly through its anti-oxidant mechanism.

Keywords: HSYA, Ischemia reperfusion injury, oxidative stress, stroke

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Authors: Peter Ekene Egwu

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Waste management is of critical importance in Africa for reasons related to public health, human dignity, climate resilience and environmental preservation. However, delivering waste management services requires adequate funding, which has generally been lacking in a context where the generation of waste is outpacing the development of waste management infrastructure in most cities. The sector represents a growing percentage of cities’ greenhouse gas (GHG) emissions, and some of the African cities profiled in this study are now designing waste management strategies with emission reduction in mind.

Keywords: management waste material, Africa, uses of new technology to manage waste, waste management

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Authors: Muntanavadee Maytapattana

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This research aims to study the effects of the Parent Training Program for Obesity Reduction (PTPOR) on child waist circumference and health behaviors of pre-school children at the Samut-Songkhram kindergarten school, Samut-Songkhram province, Thailand. The objective of this research is to evaluate the effectiveness of the PTPOR on child waist circumference and health behaviors of the pre-school children. The conceptual framework of this study is developed on the basis of the Ecological Systems Theory (EST), not only do the individual factors such as child characteristics and child risk factors contribute to the child’s weight status, but also other factors such as parenting style and family characteristics, as well as community and demographic factors. This research is a quasi-experimental study. Participants were pre-school overweight and obese children and their parents. Forty-one parent-child dyads were recruited into the program. Parents participated in two sessions including an educational session and a group discussion session. Research methodology uses Paired-Samples t-test to determine the difference between groups in the mean scores of the outcome variables of the children and parents. The research results show that there was significant difference between child waist circumferences mean score at the baseline and finishing the program at the 0.01 level (p = 0.001), mean score of the child waist circumference was decrease after finishing the program. And there was no significant difference between child exercise health behaviors mean score at the baseline and finishing the program at the 0.05 level; however, mean score of the child exercise behavior was increase after finishing the program. Meanwhile, there was significant difference between child dietary health behavior mean score at the baseline and finishing the program at the 0.01 level (p = 0.001), mean score of the child dietary was increase after finishing the program.

Keywords: PTPOR, child waist circumference, child health behaviors, pre-school children

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Authors: M. H. Rajikin, S. M. M. Syairah, A. R. Sharaniza

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Effects of nicotine on pre-partum body weight and preimplantation embryonic development has been reported previously. Present study was conducted to determine the effects of annatto (Bixa orellana)-derived delta-tocotrienol (TCT) (with presence of 10% gamma-TCT isomer) on the nicotine-induced reduction in body weight and 8-cell embryonic growth in mice. Twenty four 6-8 weeks old (23-25g) female balb/c mice were randomly divided into four groups (G1-G4; n=6). Those groups were subjected to the following treatments for 7 consecutive days: G1 (control) were gavaged with 0.1 ml tocopherol stripped corn oil, G2 was subcutaneously (s.c.) injected with 3 mg/kg/day of nicotine, G3 received concurrent treatment of nicotine (3 mg/kg/day) and 60 mg/kg/day of δ-TCT mixture (contains 90% delta & 10% gamma isomers) and G4 was given 60 mg/kg/day of δ-TCT mixture alone. Body weights were recorded daily during the treatment. On Day 8, females were superovulated with 5 IU Pregnant Mare’s Serum Gonadotropin (PMSG) for 48 hours followed with 5 IU human Chorionic Gonadotropin (hCG) before mated with males at the ratio of 1:1. Females were sacrificed by cervical dislocation for embryo collection 48 hours post-coitum. Collected embryos were cultured in vitro. Results showed that throughout Day 1 to Day 7, the body weight of nicotine treated group (G2) was significantly lower (p<0.05) than that of G1, G3 and G4. Intervention with δ-TCT mixture (G3) managed to increase the body weight close to the control group. This is also observed in the group treated with δ-TCT mixture alone (G4). The development of 8-cell embryos following in vitro culture (IVC) was totally inhibited in G2. Intervention with δ-TCT mixture (G3) resulted in the production of 8-cell embryos, although it was not up to that of the control group. Treatment with δ-TCT mixture alone (G4) caused significant increase in the average number of produced 8-cell embryo compared to G1. Present data indicated that δ-TCT mixture was able to reverse the body weight loss in nicotine treated mice and the development of 8-cell embryos was also improved.

Keywords: δ-tocotrienol, body weight, nicotine, preimplantation embryonic development

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Authors: Kayla Murray, Andrew Green, Gopi Paliyath, Keith Warriner

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Introduction: It is now acknowledged that control of human pathogens associated with fresh produce requires an integrated approach of several interventions as opposed to relying on post-harvest washes to remove field acquired contamination. To this end, current research is directed towards identifying such interventions that can be applied at different points in leafy green processing. Purpose: In the following the efficacy of different gas phase treatments to decontaminate whole lettuce heads during pre-processing storage were evaluated. Methods: Whole Cos lettuce heads were spot inoculated with L. monocytogenes, E. coli O157:H7 or Salmonella spp. The inoculated lettuce heads were then placed in a treatment chamber and exposed to ozone, chlorine dioxide or hydroxyl radicals at different time periods under a range of relative humidity. Survivors of the treatments were enumerated along with sensory analysis performed on the treated lettuce. Results: Ozone gas reduced L. monocytogenes by 2-log10 after ten-minutes of exposure with Salmonella and E. coli O157:H7 being decreased by 0.66 and 0.56-log cfu respectively. Chlorine dioxide gas treatment reduced L. monocytogenes and Salmonella on lettuce heads by 4 log cfu but only supported a 0.8 log cfu reduction in E. coli O157:H7 numbers. In comparison, hydroxyl radicals supported a 2.9 – 4.8 log cfu reduction of model human pathogens inoculated onto lettuce heads but required extended exposure times and relative humidity < 0.8. Significance: From the gas phase sanitizers tested, chlorine dioxide and hydroxyl radicals are the most effective. The latter process holds most promise based on the ease of delivery, worker safety and preservation of lettuce sensory characteristics. Although expose times for hydroxyl radicles was relatively long (24h) this should not be considered a limitation given the intervention is applied in store rooms or in transport containers during transit.

Keywords: gas phase sanitizers, iceberg lettuce heads, leafy green processing

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Authors: R. Gwynn, P. Panwalkar, K. Veravalli , M. Tofighi, R. Clement, A. Mofidi

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The aim of this study was to access the impact of Covid-19 and lockdown on the incidence, injury pattern, and treatment of tibial plateau fractures in a combined rural and urban population in wales. Methods: Retrospective study was performed to identify tibial plateau fractures in 15-month period of Covid-19 lockdown 15-month period immediately before lockdown. Patient demographics, injury mechanism, injury severity (based on Schatzker classification), and associated injuries, treatment methods, and outcome of fractures in the Covid-19 period was studied. Results: The incidence oftibial plateau fracture was 9 per 100000 during Covid-19, and 8.5 per 100000, and both were similar to previous studies. The average age was 52, and female to male ratio was 1:1 in both control and study group. High energy injury was seen in only 20% of the patients and 35% in the control groups (2=12, p<0025). 14% of the covid-19 population sustained other injuries as opposed 16% in the control group(2=0.09, p>0.95). Lower severity isolated lateral condyle fracturesinjury (Schatzker 1-3) were seen in 40% of fractures this was 60% in the control populations. Higher bicondylar and shaft fractures (Schatzker 5-6) were seen in 60% of the Covid-19 group and 35% in the control groups(2=7.8, p<0.02). Treatment mode was not impacted by Covid-19. The complication rate was low in spite of higher number of complex fractures and the impact of covid-19 pandemic. Conclusion: The associated injuries were similar in spite of a significantly lower mechanism of injury. There were unexpectedly worst tibial plateau fracture based Schatzker classification in the Covid-19 period as compared to the control groups. This was especially relevant for medial condyle and shaft fractures. This was postulated to be caused by reduction in bone density caused by lack of vitamin D and reduction in activity. The treatment mode and outcome was not impacted by the impact of Covid-19 on care for tibial plateau fractures.

Keywords: Covid-19, knee, tibial plateau fracture, trauma

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Authors: Romel Cordova Shedan

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The traditional seismic design is the methodology of Forced Based Design (FBD). The Displacement Based Design (DBD) is a seismic design that considers structural damage to achieve a failure mechanism of the structure before the collapse. It is easier to quantify damage of a structure with displacements rather than forces. Therefore, a structure to achieve an inelastic displacement design with good ductility, it is necessary to be damaged. The first part of this investigation is about differences between the methodologies of DBD and FBD with some DBD advantages. In the second part, there is a study case about a dual building 5-story, which is regular in plan and elevation. The building is located in a seismic zone, which acceleration in firm soil is 45% of the acceleration of gravity. Then it is applied both methodologies into the study case to compare its displacements, shear forces and overturning moments. In the third part, the Dynamic Time History Analysis (DTHA) is done, to compare displacements with DBD and FBD methodologies. Three accelerograms were used and the magnitude of the acceleration scaled to be spectrum compatible with design spectrum. Then, using ASCE 41-13 guidelines, the hinge plastics were assigned to structure. Finally, both methodologies results about study case are compared. It is important to take into account that the seismic performance level of the building for DBD is greater than FBD method. This is due to drifts of DBD are in the order of 2.0% and 2.5% comparing with FBD drifts of 0.7%. Therefore, displacements of DBD is greater than the FBD method. Shear forces of DBD result greater than FBD methodology. These strengths of DBD method ensures that structure achieves design inelastic displacements, because those strengths were obtained due to a displacement spectrum reduction factor which depends on damping and ductility of the dual system. Also, the displacements for the study case for DBD results to be greater than FBD and DTHA. In that way, it proves that the seismic performance level of the building for DBD is greater than FBD method. Due to drifts of DBD which are in the order of 2.0% and 2.5% compared with little FBD drifts of 0.7%.

Keywords: displacement-based design, displacement spectrum reduction factor, dynamic time history analysis, forced based design

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Authors: Maria Kralova, Michal Palecek

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We have detected factors leading to recidivism (the Czech Republic data). The employment during imprisonment turned out to be the most significant predictor with a positive effect on reduction of a rate of recidivism. Accordingly, we mainly focus on this predictor and its economic consequences. Smart public policy can cut government costs dramatically as more than a half of prisoners in the Czech Republic are recidivists. The operating cost cut of the Czech prison service could be CZK 127,680,000 (USD 5,889,623) in 2013 if a public policy had been set smarter.

Keywords: cost-cut, effective, optimal, public policy, reducing recidivism

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Authors: Bikram K. Das, Kalyan K. Chattopadhyay

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The advent of 2-D materials in the last decade has induced a fresh spur of growth in fuel cell technology as these materials have some highly promising traits that can be exploited to felicitate Oxygen Reduction Reaction (ORR) in an efficient way. Among the various 2-D carbon materials, graphyne (Gy) and graphdiyne (Gdy)1 with their intrinsic non-uniform charge distribution holds promises in this purpose and it is expected2 that substitutional Nitrogen (N) doping could further enhance their efficiency. In this regard, dispersive force corrected density functional theory is used to map the oxygen reduction reaction (ORR) kinetics of five different kinds of N doped graphyne and graphdiyne systems (namely αGy, βGy, γGy, RGy and 6,6,12Gy and Gdy) in alkaline medium. The best doping site for each of the Gy/ Gdy system is determined comparing the formation energies of the possible doping configurations. Similarly, the best di-oxygen (O₂) adsorption sites for the doped systems are identified by comparing the adsorption energies. O₂ adsorption on all N doped Gy/ Gdy systems is found to be energetically favorable. ORR on a catalyst surface may occur either via the Eley-Rideal (ER) or the Langmuir–Hinschelwood (LH) pathway. Systematic studies performed on the considered systems reveal that all of them favor the ER pathway. Further, depending on the nature of di-oxygen adsorption ORR can follow either associative or dissociative mechanism; the possibility of occurrence of both the mechanisms is tested thoroughly for each N doped Gy/ Gdy. For the ORR process, all the Gy/Gdy systems are observed to prefer the efficient four-electron pathway but the expected monotonically exothermic reaction pathway is found only for N doped 6,6,12Gy and RGy following the associative pathway and for N doped βGy, γGy and Gdy following the dissociative pathway. Further computation performed for these systems reveals that for N doped 6,6,12Gy, RGy, βGy, γGy and Gdy the overpotentials are 1.08 V, 0.94 V, 1.17 V, 1.21 V and 1.04 V respectively depicting N doped RGy is the most promising material, to carry out ORR in alkaline medium, among the considered ones. The stability of the ORR intermediate states with the variation of pH and electrode potentials is further explored with Pourbiax diagrams and the activities of these systems in the alkaline medium are compared with the prior reported B/N doped identical systems for ORR in an acidic medium in terms of a common descriptor.

Keywords: graphdiyne, graphyne, nitrogen-doped, ORR

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Authors: Sachin Kamble, Raghothama Anekal, Shivakumar Bhavi

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Thermal management of electronic components packaged inside an IP65 rated enclosure is of prime importance in industrial applications. Electrical enclosure protects the multiple board configurations such as inverter, power, controller board components, busbars, and various power dissipating components from harsh environments. Industrial environments often experience relatively warm ambient conditions, and the electronic components housed in the enclosure dissipate heat, due to which the enclosures and the components require thermal management as well as reduction of internal ambient temperatures. Design of Experiments based thermal simulation approach with MOSFET arrangement, Heat sink design, Enclosure Volume, Copper and Aluminum Spreader, Power density, and Printed Circuit Board (PCB) type were considered to optimize air temperature inside the IP65 enclosure to ensure conducive operating temperature for controller board and electronic components through the different modes of heat transfer viz. conduction, natural convection and radiation using Ansys ICEPAK. MOSFET’s with the parallel arrangement, IP65 enclosure molded heat sink with rectangular fins on both enclosures, specific enclosure volume to satisfy the power density, Copper spreader to conduct heat to the enclosure, optimized power density value and selecting Aluminum clad PCB which improves the heat transfer were the contributors towards achieving a conducive operating temperature inside the IP-65 rated Motor Inverter enclosure. A reduction of 52 ℃ was achieved in internal ambient temperature inside the IP65 enclosure between baseline and final design parameters, which met the operative temperature requirements of the electronic components inside the IP-65 rated Motor Inverter.

Keywords: Ansys ICEPAK, aluminium clad PCB, IP 65 enclosure, motor inverter, thermal simulation

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Authors: Arben Murtezani, Shefqet Mrasori, Vančo Spirov, Bukurije Rama, Oliver Dimitrovski, Visar Bunjaku

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Overview: Temporomandibular disorders (TMDs) are chronic musculoskeletal pain conditions. Clinical indicators of discomfort are related to the use of the joint stiffness during first motions after extended rest and restricted joint range of motion can cause substantial pain and disability. There is little evidence that physical therapy methods of management cause long-lasting reduction in signs and symptoms. Exercise programs premeditated to improve physical fitness have beneficial effects on chronic pain and disability of the musculoskeletal system. Objective: The aim of this study was to assess the effectiveness of physical therapy interventions in the management of temporomandibular disorders. Materials and Methods: A prospective comparative study with a 2-month follow-up period was conducted between April 2016 and June 2016 at the Physical Medicine and Rehabilitation Clinic in Prishtina. Forty six patients with TMDs, (more than three months duration of symptoms) were randomized into two groups: the TENS therapy group (n=24) and combination of active exercise and manual therapy group (n=22). The TENS therapy group patients were treated with twelve sessions of TENS. The treatment period of both groups was 3 weeks at an outpatient clinic. Following main outcome measures were evaluated: (1) pain at rest (2) pain at stress (3) impairment (4) mouth opening at base-line, before and after treatment and at 3 month follow-up. Results: Significant reduction in pain was observed in both treatment groups. In the TENS group 73% (16/22) achieved at least 80% improvement from baseline in TMJ pain at 2 months compared with 54% (13/24) in the exercise group (difference of 19%; 95% confidence interval 220 to 30%). Active and passive maximum mouth opening has been greater in the TENS group (p < 0.05). Conclusion: Exercise therapy in combination with TENS seems to be useful in the treatment of temporomandibular disorders.

Keywords: temporomandibular joint disorders, TENS, manual therapy, exercise

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Authors: Ratnakar Rao, Subair Khan, Hari Haran

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Posterior cruciate ligament (PCL) avulsion fractures is a rare condition and commonly mismanaged.Surgical reattachment has been shown to produce better result compared with conservative management.Only few techniques are reported in arthroscopic fixation of PCL Avulsion Fracture and they are complex.We describe a new technique in fixation of the PCL Avulsion fracture through a posterior trans septal portal using button fixation device (Mini Tight Rope). Eighteen patients with an isolated posterior cruciate ligament avulsion fracture were operated under arthroscopy. Standard Antero Medial Portal and Antero Lateral portals made and additional Postero Medial and Postero Lateral portals made and trans Septal portal established. Avulsion fracture identified, elevated, prepared. Reduction achieved using PCL Tibial guide (Arthrex) and fixation was achieved using Mini Tight Rope,Arthrex (2 buttons with a suture). Reduction confirmed using probe and Image intensifier. Postoperative assessment made clinically and radiologically. 15 patients had good to excellent results with no posterior sag or instability. The range of motion was normal. No complications were recorded per operatively. 2 patients had communition of the fragment while drilling, for one patient it was managed by suturing technique and the second patient PCL Reconstruction was done. One patient had persistent instability with poor outcome. Establishing trans septal portal helps in better visualization of the posterior compartment of the knee. Assessment of the bony fragment, preparation 0f the bone bed andit protects from injury to posterior neurovascular structures. Fixation using the button with suture (Mini Tight Rope) is stable and easily reproducible for PCL Avulsion fracture with single large fragment.

Keywords: PCL avulsion, arthroscopy, transeptal, minitight rope technique

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Authors: Ghodsieh Isapour Toutizad, Aiyong Wang, Joonsoo Han, Derek Creaser, Louise Olsson, Magnus Skoglundh, Hanna HaRelind

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Nitrous oxide (N2O), which is generally formed as a byproduct of industrial chemical processes and fossil fuel combustion, has attracted considerable attention due to its destructive role in global warming and ozone layer depletion. From various developed technologies used for lean NOx reduction, the selective catalytic reduction (SCR) of NOx with ammonia is presently the most applied method. Therefore, the development of catalysts for efficient lean NOx reduction without forming N2O in the process, or only forming it to a very small extent from the exhaust gases is of crucial significance. One type of catalysts that nowadays are used for this aim are zeolite-based catalysts. It is owing to their remarkable catalytic performance under practical reaction conditions such as high thermal stability and high N2 selectivity. Among all zeolites, copper ion-exchanged zeolites, with CHA, MFI, and BEA framework structure (like SSZ-13, ZSM-5 and Beta, respectively), represent higher hydrothermal stability, high activity and N2 selectivity. This work aims at investigating the effect of the zeolite framework structure on the formation of N2O during NH3-SCR reaction conditions over three Cu-based zeolites ranging from small-pore to large-pore framework structure. In the zeolite framework, Cu exists in two cationic forms, that can catalyze the SCR reaction by activating NO to form NO+ and/or surface nitrate species. The nitrate species can thereafter react with NH3 to form another intermediate, ammonium nitrate, which seems to be one source for N2O formation at low temperatures. The results from in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) indicate that during the NO oxidation step, mainly NO+ and nitrate species are formed on the surface of the catalysts. The intensity of the absorption peak attributed to NO+ species is higher for the Cu-CHA sample compared to the other two samples, indicating a higher stability of this species in small cages. Furthermore, upon the addition of NH3, through the standard SCR reaction conditions, absorption peaks assigned to N-H stretching and bending vibrations are building up. At the same time, negative peaks are evolving in the O-H stretching region, indicating blocking/replacement of surface OH-groups by NH3 and NH4+. By removing NH3 and adding NO2 to the inlet gas composition, the peaks in the N-H stretching and bending vibration regions show a decreasing trend in intensity, with the decrease being more pronounced for increasing pore size. It can probably be owing to the higher accumulation of ammonia species in the small-pore size zeolite compared to the other two samples. Furthermore, it is worth noting that the ammonia surface species are strongly bonded to the CHA zeolite structure, which makes it more difficult to react with NO2. To conclude, the framework structure of the zeolite seems to play an important role in the formation and reactivity of surface species relevant for the SCR process. Here we intend to discuss the connection between the zeolite structure, the surface species, and the formation of N2O during ammonia-SCR.

Keywords: fast SCR, nitrous oxide, NOx, standard SCR, zeolites

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Authors: Y. Fandja, O. Colot, M. Croquet

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Small and medium-sized firms (SMEs) face difficulties in accessing bank credit. Bank credit is actually the main source of external financing for SMEs. In general, SMEs are risky businesses because of the potential opacity maintained by the leader in the management of affairs, the agency conflicts between business owners and third-party funders and the potential opportunism of the leader due to the incompleteness of the contracts. These elements accentuate the problems of information asymmetries between SMEs and bankers leading to capital rationing. Moreover, the last economic crisis reinforced this rationing of capital. However, a long-term relationship between SMEs and their bank would enable the latter to accumulate a set of relevant information allowing the reduction of information asymmetry and, consequently, the reduction of credit rationing. The objective of this research is to investigate the lived experience of SMEs loan officers in their relationships with their clients in order to understand how these relationships can affect the financing structure of these SMEs. To carry out this research, an Interpretative Phenomenological Analysis is implemented. This approach is part of the constructivist paradigm and refers to the subjective narratives of the individual rather than to an objective description of the facts. The role of the researcher is to explore the lived experience of the interviewees and to try to understand the meaning they give to this experience. Currently, several sixty-minute semi-structured interviews with loan officers for SMEs have been conducted. The analysis of the content of these interviews brought out three main themes. First, the relationship between the credit officer and the company manager is complex because the credit officer is not aware of establishing a personal relationship with his client. Second; the emotional involvement in the bank financing decision is present and third, the trust in the relationship between the credit officer and his client is very important. The originality of this research is to use the interpretative phenomenological analysis more specific to psychology and sociology in order to approach in a different way the problem of the financing of SMEs through their particular relations with the bankers.

Keywords: financing structure, interpretative phenomenological analysis, relationship financing, SME

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