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Authors: Abdelmoniem A. Attaelmanan, Ahmed A. H. Siddig

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This study was conducted in light of continual global climate changes that projected increasing aridity, changes in soil fertility, and pollution. Plant growth and development largely depend on the combination of availing water and nutrients in the soil. Changes in the climate and atmospheric chemistry can cause serious effects on these growth factors. Plant carbon (C), nitrogen (N), and hydrogen (H) play a fundamental role in the maintenance of ecosystem structure and function. Hashab (Acacia senegal), which produces gum Arabic, supports dryland ecosystems in tropical zones by its potentiality to restore degraded soils; hence it is ecologically and economically important for the dry areas of sub-Saharan Africa. The study aims at investigating the effects of water stress (simulated drought) and poor soil type on Acacia senegal C, N, and H contents. Seven days old seedlings were assigned to the treatments in Split- plot design for four weeks. The main plot is irrigation interval (well-watered and water-stressed), and the subplot is soil types (silt and sand soils). Seedling's C%, N%, and H% were measured using CHNS-O Analyzer and applying Standard Test Method. Irrigation intervals and soil types had no effects on seedlings and leaves C%, N%, and H%, irrigation interval had affected stem C and H%, both irrigation intervals and soil types had affected root N% and interaction effect of water and soil was found on leaves and root's N%. Synthesis application of well-watered irrigation with soil that is rich in N and other nutrients would result in the greatest seedling C, N, and H content which will enhance growth and biomass accumulation and can play a crucial role in ecosystem productivity and services in the dryland regions.

Keywords: Acacia senegal, Africa, climate change, drylands, nutrients biomass, Sub-Saharan, Sudan

Procedia PDF Downloads 83

Authors: Adel Dalilottojari, Bahman Delalat, Frances J. Harding, Michaelia P. Cockshell, Claudine S. Bonder, Nicolas H. Voelcker

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Endothelial Progenitor Cell (EPC) based therapies continue to be of interest to treat ischemic events based on their proven role to promote blood vessel formation and thus tissue re-vascularisation. Current strategies for the production of clinical-grade EPCs requires the in vitro isolation of EPCs from peripheral blood followed by cell expansion to provide sufficient quantities EPCs for cell therapy. This study aims to examine the use of different biomolecules to significantly improve the current strategy of EPC capture and expansion on collagen type I (Col I). In this study, four different biomolecules were immobilised on a surface and then investigated for their capacity to support EPC capture and proliferation. First, a cell microarray platform was fabricated by coating a glass surface with epoxy functional allyl glycidyl ether plasma polymer (AGEpp) to mediate biomolecule binding. The four candidate biomolecules tested were Col I, collagen type II (Col II), collagen type IV (Col IV) and vascular endothelial growth factor A (VEGF-A), which were arrayed on the epoxy-functionalised surface using a non-contact printer. The surrounding area between the printed biomolecules was passivated with polyethylene glycol-bisamine (A-PEG) to prevent non-specific cell attachment. EPCs were seeded onto the microarray platform and cell numbers quantified after 1 h (to determine capture) and 72 h (to determine proliferation). All of the extracellular matrix (ECM) biomolecules printed demonstrated an ability to capture EPCs within 1 h of cell seeding with Col II exhibiting the highest level of attachment when compared to the other biomolecules. Interestingly, Col IV exhibited the highest increase in EPC expansion after 72 h when compared to Col I, Col II and VEGF-A. These results provide information for significant improvement in the capture and expansion of human EPC for further application.

Keywords: biomolecules, cell microarray platform, cell therapy, endothelial progenitor cells, high throughput screening

Procedia PDF Downloads 263

Authors: Sung-Jun Yoo, Kazuhide Ito

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In this study, a comprehensive computer simulated person (CSP) that integrates computational human model (virtual manikin) and respiratory tract model (virtual airway), was applied for estimation of indoor environmental quality. Moreover, an inclusive prediction method was established by integrating computational fluid dynamics (CFD) analysis with advanced CSP which is combined with physiologically-based pharmacokinetic (PBPK) model, unsteady thermoregulation model for analysis targeting micro-climate around human body and respiratory area with high accuracy. This comprehensive method can estimate not only the contaminant inhalation but also constant interaction in the contaminant transfer between indoor spaces, i.e., a target area for indoor air quality (IAQ) assessment, and respiratory zone for health risk assessment. This study focused on the usage of the CSP as an air/thermal quality sensor in indoors, which means the application of comprehensive model for assessment of IAQ and thermal environmental quality. Demonstrative analysis was performed in order to examine the applicability of the comprehensive model to the heating, ventilation, air conditioning (HVAC) control scheme. CSP was located at the center of the simple model room which has dimension of 3m×3m×3m. Formaldehyde which is generated from floor material was assumed as a target contaminant, and flow field, sensible/latent heat and contaminant transfer analysis in indoor space were conducted by using CFD simulation coupled with CSP. In this analysis, thermal comfort was evaluated by thermoregulatory analysis, and respiratory exposure risks represented by adsorption flux/concentration at airway wall surface were estimated by PBPK-CFD hybrid analysis. These Analysis results concerning IAQ and thermal comfort will be fed back to the HVAC control and could be used to find a suitable ventilation rate and energy requirement for air conditioning system.

Keywords: CFD simulation, computer simulated person, HVAC control, indoor environmental quality

Procedia PDF Downloads 323

Authors: J. Hrabovský, M. Chabičovský, J. Horský

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Water spray cooling is a technique typically used in heat treatment and other metallurgical processes where controlled temperature regimes are required. Water spray cooling is used in static (without movement) or dynamic (with movement of the steel plate) regimes. The static regime is notable for the fixed position of the hot steel plate and fixed spray nozzle. This regime is typical for quenching systems focused on heat treatment of the steel plate. The second application of spray cooling is the dynamic regime. The dynamic regime is notable for its static section cooling system and moving steel plate. This regime is used in rolling and finishing mills. The fixed position of cooling sections with nozzles and the movement of the steel plate produce nonhomogeneous water distribution on the steel plate. The length of cooling sections and placement of water nozzles in combination with the nonhomogeneity of water distribution leads to discontinued or interrupted cooling conditions. The impact of static and dynamic regimes on cooling intensity and the heat transfer coefficient during the cooling process of steel plates is an important issue. Heat treatment of steel is accompanied by oxide scale growth. The oxide scale layers can significantly modify the cooling properties and intensity during the cooling. The combination of the static and dynamic (section) regimes with the variable thickness of the oxide scale layer on the steel surface impact the final cooling intensity. The study of the influence of the oxide scale layers with different cooling regimes was carried out using experimental measurements and numerical analysis. The experimental measurements compared both types of cooling regimes and the cooling of scale-free surfaces and oxidized surfaces. A numerical analysis was prepared to simulate the cooling process with different conditions of the section and samples with different oxide scale layers.

Keywords: heat transfer coefficient, numerical analysis, oxide layer, spray cooling

Procedia PDF Downloads 376

Authors: N. Lakshmipathy, Ch. S. N. Murthy, M. Aruna

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The design of lighting systems for surface mines is not an easy task because of the unique environment and work procedures encountered in the mines. The primary objective of this paper is to identify the major problems encountered in mine lighting application and to provide guidance in the solution of these problems. In the surface mining reflectance of surrounding surfaces is one of the important factors, which improve the vision, in the night hours. But due to typical working nature in the mines it is very difficult to fulfill these requirements, and also the orientation of the light at work site is a challenging task. Due to this reason machine operator and other workers in a mine need to be able to orient themselves in a difficult visual environment. The haul roads always keep on changing to tune with the mining activity. Other critical area such as dumpyards, stackyards etc. also change their phase with time, and it is difficult to illuminate such areas. Mining is a hazardous occupation, with workers exposed to adverse conditions; apart from the need for hard physical labor, there is exposure to stress and environmental pollutants like dust, noise, heat, vibration, poor illumination, radiation, etc. Visibility is restricted when operating load haul dumper and Heavy Earth Moving Machinery (HEMM) vehicles resulting in a number of serious accidents. one of the leading causes of these accidents is the inability of the equipment operator to see clearly people, objects or hazards around the machine. Results indicate blind spots are caused primarily by posts, the back of the operator's cab, and by lights and light brackets. The careful designed and implemented, lighting systems provide mine workers improved visibility and contribute to improved safety, productivity and morale. Properly designed lighting systems can improve visibility and safety during working in the opencast mines.

Keywords: contrast, efficacy, illuminance, illumination, light, luminaire, luminance, reflectance, visibility

Procedia PDF Downloads 333

Authors: Cristian Matti, Valerie Fowles, Eva Enyedi, Piotr Pogorzelski

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The system mapping process can be defined as a knowledge service where a team of facilitators, experts and practitioners facilitate a guided conversation, enable the exchange of information and support an iterative curation process. System mapping processes rely on science-based tools to introduce and simplify a variety of components and concepts of socio-technical systems through metaphors while facilitating an interactive dialogue process to enable the design of co-created maps. System maps work then as “artifacts” to provide information and focus the conversation into specific areas around the defined challenge and related decision-making process. Knowledge management facilitates the curation of that data gathered during the system mapping sessions through practices of documentation and subsequent knowledge co-production for which common practices from data science are applied to identify new patterns, hidden insights, recurrent loops and unexpected elements. This study presents empirical evidence on the application of these techniques to explore mechanisms by which visual tools provide guiding principles to portray system components, key variables and types of data through the lens of climate change. In addition, data science facilitates the structuring of elements that allow the analysis of layers of information through affinity and clustering analysis and, therefore, develop simple indicators for supporting the decision-making process. This paper addresses methodological and empirical elements on the horizontal learning process that integrate system mapping through visual tools, interpretation, cognitive transformation and analysis. The process is designed to introduce practitioners to simple iterative and inclusive processes that create actionable knowledge and enable a shared understanding of the system in which they are embedded.

Keywords: indicators, knowledge management, system mapping, visual tools

Procedia PDF Downloads 161

Authors: Neel K. Shah

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Passive flow control on aerofoils has largely been achieved through the use of protrusions such as vane-type vortex generators. Consequently, innovative flow-control concepts should be explored in an effort to improve current component performance. Therefore, experimental research has been performed at The University of Manchester to evaluate the flow-control effectiveness of a vortex generator made in the form of a surface indentation. The surface indentation has a trapezoidal planform. A spanwise array of indentations has been applied in a convergent orientation around the maximum-thickness location of the upper surface of a NACA-0015 aerofoil. The aerofoil has been tested in a two-dimensional set-up in a low-speed wind tunnel at an angle of attack (AoA) of 3° and a chord-based Reynolds number (Re) of ~2.7 x 105. The baseline model has been found to suffer from a laminar separation bubble at low AoA. The application of the indentations at 3° AoA has considerably shortened the separation bubble. The indentations achieve this by shedding up-flow pairs of streamwise vortices. Despite the considerable reduction in bubble length, the increase in leading-edge suction due to the shorter bubble is limited by the removal of surface curvature and blockage (increase in surface pressure) caused locally by the convergent indentations. Furthermore, the up-flow region of the vortices, which locally weakens the pressure recovery around the trailing edge of the aerofoil by thickening the boundary layer, also contributes to this limitation. Due to the conflicting effects of the indentations, the changes in the pressure-lift and pressure-drag coefficients, i.e., cl,p and cd,p, are small. Nevertheless, the indentations have improved cl,p and cd,p beyond the uncertainty range, i.e., by ~1.30% and ~0.30%, respectively, at 3° AoA. The wake measurements show that turbulence intensity and Reynolds stresses have considerably increased in the indented case, thus implying that the indentations increase the viscous drag on the model. In summary, the convergent indentations are able to reduce the size of the laminar separation bubble, but conversely, they are not highly effective in reducing cd,p at the tested Reynolds number.

Keywords: aerofoil flow control, laminar separation bubbles, low Reynolds-number flows, surface indentations

Procedia PDF Downloads 206

Authors: Sipho Mbatha, Anne Mastament-Mason

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South African manufacturing global competitiveness was ranked 22nd (out of 38 countries), dropped to 24th in 2013 and is expected to drop further to 25th by 2018. These impacts negatively on the industrialisation project of South Africa. For industrialization to be achieved through labour intensive industries like the Apparel Manufacturing Industries of South Africa (AMISA), South Africa needs to identify and respond to factors negatively impacting on the development of competitive advantage This paper applied factor conditions from Porter’s Diamond Model (1990) to understand the various challenges facing the AMISA. Factor conditions highlighted in Porter’s model are grouped into two groups namely, basic and advance factors. Two AMISA associations representing over 10 000 employees were interviewed. The largest Clothing, Textiles and Leather (CTL) apparel retail group was also interviewed with a government department implementing the industrialisation policy were interviewed The paper points out that while AMISA have basic factor conditions necessary for competitive advantage in the clothing and textiles industries, Advance factor coordination has proven to be a challenging task for the AMISA, Higher Education Institutions (HEIs) and government. Poor infrastructural maintenance has contributed to high manufacturing costs and poor quick response as a result of lack of advanced technologies. The use of Porter’s Factor Conditions as a tool to analyse the sector’s competitive advantage challenges and opportunities has increased knowledge regarding factors that limit the AMISA’s competitiveness. It is therefore argued that other studies on Porter’s Diamond model factors like Demand conditions, Firm strategy, structure and rivalry and Related and supporting industries can be used to analyse the situation of the AMISA for the purposes of improving competitive advantage.

Keywords: compliance rule, apparel manufacturing industry, factor conditions, advance skills and South African industrial policy

Procedia PDF Downloads 336

Authors: Maja Ruzic-Baf, Vedrana Keteles, Andrea Debeljuh

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Younger and younger children are now using a smartphone, a device which has become ‘a must have’ and the life of children would be almost ‘unthinkable’ without one. Devices are becoming lighter and lighter but offering an array of options and applications as well as the unavoidable access to the Internet, without which it would be almost unusable. Numerous features such as taking of photographs, listening to music, information search on the Internet, access to social networks, usage of some of the chatting and messaging services, are only some of the numerous features offered by ‘smart’ devices. They have replaced the alarm clock, home phone, camera, tablet and other devices. Their use and possession have become a part of the everyday image of young people. Apart from the positive aspects, the use of smartphones has also some downsides. For instance, free time was usually spent in nature, playing, doing sports or other activities enabling children an adequate psychophysiological growth and development. The greater usage of smartphones during classes to check statuses on social networks, message your friends, play online games, are just some of the possible negative aspects of their application. Considering that the age of the population using smartphones is decreasing and that smartphones are no longer ‘foreign’ to children of pre-school age (smartphones are used at home or in coffee shops or shopping centers while waiting for their parents, playing video games often inappropriate to their age), particular attention must be paid to a very sensitive group, the teenagers who almost never separate from their ‘pets’. This paper is divided into two sections, theoretical and empirical ones. The theoretical section gives an overview of the pros and cons of the usage of smartphones, while the empirical section presents the results of a research conducted in three elementary schools regarding the usage of smartphones and, specifically, their usage during classes, during breaks and to search information on the Internet, check status updates and 'likes’ on the Facebook social network.

Keywords: education, smartphone, social networks, teenagers

Procedia PDF Downloads 427

Authors: Pratap K. Chhotaray, Jitendriya Swain, Ashok Mishra, Ramesh L. Gardas

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Ionic liquids (ILs) are molten salts, consist predominantly of ions and found to be liquid below 100°C. The unparalleled growing interest in ILs is based upon their never ending design flexibility. The use of ILs as a co-solvent in binary as well as a ternary mixture with molecular solvents multifold it’s utility. Since polarity is one of the most widely applied solvent concepts which represents simple and straightforward means for characterizing and ranking the solvent media, its study for a binary mixture of ILs is crucial for its widespread application and development. The primary approach to the assessment of solution phase intermolecular interactions, which generally occurs on the picosecond to nanosecond time scales, is to exploit the optical response of photophysical probe. Pyrene butyric acid (PBA) is used as fluorescence probe due to its high quantum yield, longer lifetime and high solvent polarity dependence of fluorescence spectra. Propylammonium formate (PAF) is the IL used for this study. Both the UV-absorbance spectra and steady state fluorescence intensity study of PBA in different concentration of aqueous PAF, reveals that with an increase in PAF concentration, both the absorbance and fluorescence intensity increases which indicate the progressive solubilisation of PBA. Whereas, near about 50% of IL concentration, all of the PBA molecules get solubilised as there are no changes in the absorbance and fluorescence intensity. Furthermore, the ratio II/IV, where the band II corresponds to the transition from S1 (ν = 0) to S0 (ν = 0), and the band IV corresponds to transition from S1 (ν = 0) to S0 (ν = 2) of PBA, indicates that the addition of water into PAF increases the polarity of the medium. Time domain lifetime study shows an increase in lifetime of PBA towards the higher concentration of PAF. It can be attributed to the decrease in non-radiative rate constant at higher PAF concentration as the viscosity is higher. The monoexponential decay suggests that homogeneity of solvation environment whereas the uneven width at full width at half maximum (FWHM) indicates there might exist some heterogeneity around the fluorophores even in the water-IL mixed solvents.

Keywords: fluorescence, ionic liquid, lifetime, polarity, pyrene butyric acid

Procedia PDF Downloads 425

Authors: Nada Basset

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Problem Statement: The study examines the important role of leading change inside start-ups and highlights the challenges faced by an entrepreneur during the startup phase of the business. Research Methods/Procedures/Approaches: A qualitative research approach is taken, using the case study analysis method. A comparative study was made between two day care nurseries in Greater Cairo. Non-probability purposive sampling was used and a triangulation of semi-structured interviews, document analysis and participant-observation were applied simultaneously. The in-depth case study analysis took place over a longitudinal study of four calendar months. Results/Findings: Findings demonstrated that leading change in an entrepreneurial setup must be initiated by the entrepreneur, who must also be the owner of the change process. Another important finding showed that the culture of change, although created by the entrepreneur, needs the support and engagement of followers, who should be sharing the same value system and vision of the entrepreneur. Conclusions and Implications: An important implication suggests that during the first year of a start-up lifecycle, special emphasis must be made to the recruitment and selection of personnel, who should play a role into setting the new start-up culture and help it grow or shrink. Another drawn conclusion is that the success of the change must be measured in both quantitative and qualitative terms. Increasing revenues and customer attrition rates -as quantitative KPIs- must be aligned with other qualitative KPIs like customer satisfaction, employee satisfaction, and organizational commitment and business reputation. Originality of Paper: The paper addresses change management in an entrepreneurial concept, with an empirical application on an Egyptian start-up model providing a service to both adults and children. This privileges the research as the constructs measured merged together the level of satisfaction of employees, decision-makers (parents of children), and the users (children).

Keywords: leadership, change management, entrepreneurship, startup business

Procedia PDF Downloads 155

Authors: Ranjit Kumar Sahu, Ramakar Jha

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Urban Water Management is the practice of managing freshwater, waste water, and storm water as components of a basin-wide management plan. It builds on existing water supply and sanitation considerations within an urban settlement by incorporating urban water management within the scope of the entire river basin. The pervasive problems generated by urban development have prompted, in the present work, to study the spatial extent of urbanization in Golden Triangle of Odisha connecting the cities Bhubaneswar (20.2700° N, 85.8400° E), Puri (19.8106° N, 85.8314° E) and Konark (19.9000° N, 86.1200° E)., and patterns of periodic changes in urban development (systematic/random) in order to develop future plans for (i) urbanization promotion areas, and (ii) urbanization control areas. Remote Sensing, using USGS (U.S. Geological Survey) Landsat8 maps, supervised classification of the Urban Sprawl has been done for during 1980 - 2014, specifically after 2000. This Work presents the following: (i) Time series analysis of Hydrological data (ground water and rainfall), (ii) Application of SWMM (Storm Water Management Model) and other soft computing techniques for Urban Water Management, and (iii) Uncertainty analysis of model parameters (Urban Sprawl and correlation analysis). The outcome of the study shows drastic growth results in urbanization and depletion of ground water levels in the area that has been discussed briefly. Other relative outcomes like declining trend of rainfall and rise of sand mining in local vicinity has been also discussed. Research on this kind of work will (i) improve water supply and consumption efficiency (ii) Upgrade drinking water quality and waste water treatment (iii) Increase economic efficiency of services to sustain operations and investments for water, waste water, and storm water management, and (iv) engage communities to reflect their needs and knowledge for water management.

Keywords: Storm Water Management Model (SWMM), uncertainty analysis, urban sprawl, land use change

Procedia PDF Downloads 402

Authors: Amal Shehata

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Low back pain related to disc prolapse is localized in the lumbar area and it may be radiated to the lower extremities, starting from neurons near or around the spinal canal. Most of the population may be affected with disc prolapse within their lifetime and leads to lost productivity, disability and loss of function. The study purpose was to examine the effect of rehabilitative nursing program on pain intensity and functional status among patients with discectomy. Design: Aquasi experimental design was utilized. Setting: The study was carried out at neurosurgery department and out patient's clinic of Menoufia University and Teaching hospitals at Menoufia governorate, Egypt. Instrument of the study: Five Instruments were used for data collection: Structured interviewing questionnaire, Functional assessment instrument, Observational check list, Numeric rating Scale and Oswestry low back pain disability questionnaire. Results: There was an improvement in mean total knowledge score about disease process, discectomy and rehabilitation program in study group (25.32%) than control group (7.32%). There was highly statistically significant improvement in lumbar flexibility among study group (80%) than control group (30%) after rehabilitation program than before. Also there was a decrease in pain score in study group (58% no pain) than control group (28% no pain) after rehabilitation program. There was an improvement in total disability score of study group (zero %) regarding effect of pain on the activity of daily living after rehabilitation program than control group (16%). Conclusion: Application of rehabilitative nursing program for patient with discectomy had proven a positive effect in relation to knowledge score, pain reduction, activity of daily living and functional abilities. Recommendation: A continuous rehabilitative nursing program should be carried out for all patients immediately after discectomy surgery on regular basis. Also A colored illustrated booklet about rehabilitation program should be available and distributed for all patients before surgery.

Keywords: discectomy, rehabilitative nursing program, pain intensity, functional status

Procedia PDF Downloads 117

Authors: Elisa K. Schoenell, Cristiano De Oliveira, Luiz R. H. Dos Santos, Alexandre Giacobbo, Andréa M. Bernardes, Marco A. S. Rodrigues

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Water is an indispensable natural resource, which must be preserved to human activities as well the ecosystems. However, the sewage discharge has been contaminating water resources. Conventional treatment, such as physicochemical treatment followed by biological processes, has not been efficient to the complete degradation of persistent organic compounds, such as medicines and hormones. Therefore, the use of advanced technologies to sewage treatment has become urgent and necessary. The aim of this study was to apply Reverse Osmosis (RO) on sewage tertiary treatment from a Waste Water Treatment Plant (WWTP) in south Brazil. It was collected 200 L of sewage pre-treated by wetland with aquatic macrophytes. The sewage was treated in a RO pilot plant, using a polyamide membrane BW30-4040 model (DOW FILMTEC), with 7.2 m² membrane area. In order to avoid damage to the equipment, this system contains a pleated polyester filter with 5 µm pore size. It was applied 8 bar until achieve 5 times of concentration, obtaining 80% of recovery of permeate, with 10 L.min-1 of concentrate flow rate. Samples of sewage pre-treated on WWTP, permeate and concentrate generated on RO was analyzed for physicochemical parameters and by gas chromatography (GC) to qualitative analysis of organic compounds. The results proved that the sewage treated on WWTP does not comply with the limit of phosphorus and nitrogen of Brazilian legislation. Besides this, it was found many organic compounds in this sewage, such as benzene, which is carcinogenic. Analyzing permeate results, it was verified that the RO as sewage tertiary treatment was efficient to remove of physicochemical parameters, achieving 100% of iron, copper, zinc and phosphorus removal, 98% of color removal, 91% of BOD and 62% of ammoniacal nitrogen. RO was capable of removing organic compounds, however, it was verified the presence of some organic compounds on de RO permeate, showing that RO did not have the capacity of removal all organic compounds of sewage. It has to be considered that permeate showed lower intensity of peaks in chromatogram in comparison to the sewage of WWTP. It is important to note that the concentrate generate on RO needs a treatment before its disposal in environment.

Keywords: organic compounds, reverse osmosis, sewage treatment, tertiary treatment

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Authors: Abdul Matin, Muazzama Akhtar, Shahid Nisar, Saddaf Mazzar, Umer Rashid

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Antibiotic resistance is an increasing concern worldwide now a day. Neisseria gonorrhea and Staphylococcus aureus are known to cause major human sexually transmitted and respiratory diseases respectively. Nanotechnology is an emerging discipline and its application in various fields especially in medical sciences is gigantic. In the present study, we synthesized multi-walled carbon nanotubes (MWNTs) using acid oxidation method and solubilized MWNTs were with length predominantly >500 nm and diameters ranging from 40 to 50 nm. The locally synthesized MWNTs were used against gram positive and negative bacteria to determine their impact on bacterial growth. Clinical isolates of Neisseria gonorrhea (isolate: 4C-11) and Staphylococcus aureus (isolate: 38541) were obtained from local hospital and normally cultured in LB broth at 37°C. Both clinical strains can be obtained on request from University of Gujarat. Spectophometric assay was performed to determine the impact of MWNTs on bacterial growth in vitro. To determine the effect of MWTNs on test organisms, various concentration of MWNTs were used and recorded observation on various time intervals to understand the growth inhibition pattern. Our results demonstrated that MWNTs exhibited toxic effects to Staphylococcus aureus while showed very limited growth inhibition to Neisseria gonorrhea, which suggests the resistant potential of Neisseria against nanoparticles. Our results clearly demonstrate the gradual decrease in bacterial numbers with passage of time when compared with control. Maximum bacterial inhibition was observed at maximum concentration (50 µg/ml). Our future work will include further characterization and mode of action of our locally synthesized MWNTs. In conclusion, we investigated and reported for the first time the inhibitory potential of locally synthesized MWNTs on local clinical isolates of Staphylococcus aureus and Neisseria gonorrhea.

Keywords: antibacterial activity, multi walled carbon nanotubes, Neisseria gonorrhea, spectrophotometer assay, Staphylococcus aureus

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Authors: Sayed M. Ahmed, Sawsan S. Darwish, Mahmoud A. Adam, Nagib A. Elmarzugi, Mohammad A. Al-Dosari, Nadia A. Al-Mouallimi

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Historical stone surfaces and architectural heritage especially which located in open areas may undergo unwanted changes due to the exposure to many physical and chemical deterioration factors, air pollution, soluble salts, Rh/temperature, and biodeterioration are the main causes of decay of stone building materials. The development and application of self-cleaning treatments on historical and architectural stone surfaces could be a significant improvement in conservation, protection, and maintenance of cultural heritage. In this paper, nanometric titanium dioxide has become a promising photocatalytic material owing to its ability to catalyze the complete degradation of many organic contaminants and represent an appealing way to create self-cleaning surfaces, thus limiting maintenance costs, and to promote the degradation of polluting agents. The obtained nano-TiO2 coatings were applied on travertine (Marble and limestone often used in historical and monumental buildings). The efficacy of the treatments has been evaluated after coating and artificial thermal aging, through capillary water absorption, Ultraviolet-light exposure to evaluate photo-induced and the hydrophobic effects of the coated surface, while the surface morphology before and after treatment was examined by scanning electron microscopy (SEM). The changes of molecular structure occurring in treated samples were spectroscopy studied by FTIR-ATR, and Colorimetric measurements have been performed to evaluate the optical appearance. All the results get together with the apparent effect that coated TiO2 nanoparticles is an innovative method, which enhanced the durability of stone surfaces toward UV aging, improved their resistance to relative humidity and temperature, self-cleaning photo-induced effects are well evident, and no alteration of the original features.

Keywords: architectural calcareous stone monuments, coating, photocatalysis TiO2, self-cleaning, thermal aging

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Authors: Ana M. G. Sperandio, Adriana A. C. Rosa, Jussara C. Guarnieri

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This study consists of a research of the Post Occupancy Assessment (POA) of Medicinal Gardens' project of Urban Social Center’s square, in the city of 'Santa Barbara d'Oeste', located in the interior of Sao Paulo, Brazil. In view of the fact that community gardens, as well as medicinal gardens, are based on innumerable functions. The addition to the pedagogical function rescues people from their origins through (re)contact with the land, as a vehicle for social integration. Bearing in mind the project has the potential to fight hunger among the low-income population, to treat some diseases, also works as a strategy of environmental recovery especially of idle land. Such as very often only accumulate weeds and garbage, and therefore, must be considered in the Municipal Master Plan for the activity to be regulated. Objective: Identify on implantation the medicinal plants' value and principles for the promotion of a healthy city. Methodology: Application of the walkthrough, where it is possible to affirm that this instrument has three routes: one officer applied within the urban social center and two complementary ones, one being about 3 miles and the other being almost 5,5 miles. Results: Through a dialogical course, one can observe the benefits that the community medicinal gardens bring to the local population. In addition, it is consistent with the proposal for the community to be enabled to access collective care with home orientations that rescue the local and regional culture making the physical environment. This project aims at promoting more pleasant and inclusive through the actions of the caregiver, local leadership and the co-participation of local government. Although with the aim of increasing the supply value and improving the living conditions of social groups and interrelationship. Conclusion: This type of urban intervention, which articulates social participation, rescue of medicinal cultures and local knowledge, intersectoriality, social inclusion, among other premises connected with health promotion, and the city presents a potential for reverberation of practices in social networks with the objective of meeting the healthy city strategies.

Keywords: healthy city, healthy urban planning, medicinal gardens, social participation

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Authors: Rajashree Naik, Laxmi Kant Sharma

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Sambhar lake is the largest inland Salt Lake of India, declared as a Ramsar site on 23 March 1990. Due to high salinity and alkalinity condition its biodiversity richness is contributed by haloalkaliphilic flora and fauna along with the diverse land cover including waterbody, wetland, salt crust, saline soil, vegetation, scrub land and barren land which welcome large number of flamingos and other migratory birds for winter harboring. But with the gradual increase in the irrational salt extraction activities, the ecological diversity is at stake. There is an urgent need to assess the ecosystem. Advanced technology like remote sensing and GIS has enabled to look into the past, compare with the present for the future planning and management of the natural resources in a judicious way. This paper is a research work intended to present a vegetation in typical inland lake environment of Sambhar wetland using satellite data of NASA’s EO-1 Hyperion sensor launched in November 2000. With the spectral range of 0.4 to 2.5 micrometer at approximately 10nm spectral resolution with 242 bands 30m spatial resolution and 705km orbit was used to produce a vegetation map for a portion of the wetland. The vegetation map was tested for classification accuracy with a pre-existing detailed GIS wetland vegetation database. Though the accuracy varied greatly for different classes the algal communities were successfully identified which are the major sources of food for flamingo. The results from this study have practical implications for uses of spaceborne hyperspectral image data that are now becoming available. Practical limitations of using these satellite data for wetland vegetation mapping include inadequate spatial resolution, complexity of image processing procedures, and lack of stereo viewing.

Keywords: Algal community, NASA’s EO-1 Hyperion, salt-tolerant species, wetland vegetation mapping

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Authors: Meriem Abid, Erika Oliveria-Jardim, Andres Fullana, Joaquin Silvestre-Albero

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The rapid industrial development associated with the increase of volatile organic compounds (VOCs) has seriously impacted the environment. Among VOCs, hydrogen sulfide (H₂S) is known as a highly toxic, malodorous, flammable, and corrosive gas, which is emitted from diverse chemical processes, including industrial waste-gas streams, natural gas processing, and biogas purification. The high toxicity, corrosively, and very characteristic odor threshold of H2S call for urgent development of efficient desulfurization processes from the viewpoint of environmental protection and resource regeneration. In order to reduce H₂S emissions, effective technologies for have been performed. The general method of H₂S removal included amine aqueous solution, adsorption process, biological methods, and fixed-bed solid catalytic oxidation processes. Ecologically and economically, low-temperature direct oxidation of H₂S to elemental sulfur using catalytic oxidation is the preferred approach for removing H₂S-containing gas streams. A large number of catalysts made from carbon, metal oxides, clay, and others, have been studied extensively for this application. In this sense, activated carbon (AC) is an attractive catalyst for H₂S removal because it features a high specific surface area, diverse functional groups, low cost, durability, and high efficiency. It is interesting to stand out that AC is modified using metal oxides to promote the efficiency of H₂S removal and to enhance the catalytic performance. Based on these premises, the main goal of the present study is the evaluation of the H₂S adsorption performance in carbon-encapsulated iron nanoparticles obtained from an olive mill, thermally treated at 600, 800 and 1000 ºC temperatures under anaerobic conditions. These results anticipate that carbon-encapsulated iron nanoparticles exhibit a promising performance for the H₂S removal up to 360 mg/g.

Keywords: H₂S removal, catalytic oxidation, carbon encapsulated iron, olive mill wastewater

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Authors: Ifeanyichukwu Edeh, Tim Overton, Steve Bowra

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Currently biodiesel is produced from plant oils or animal’s fats by a liquid-phase catalysed transesterification process at low temperature. Although biodiesel is renewable and to a large extent sustainable, inherent properties such as poor cold flow, low oxidation stability, low cetane value restrict application to blends with fossil fuels. An alternative to biodiesel is renewable diesel produced by catalytic hydrotreating of oils and fats and is considered a drop in fuel because its properties are similar to petroleum diesel. In addition to developing alternative productions routes there is continued interest in reducing the cost of the feed stock, waste cooking oils and fats are increasingly used as the feedstocks due to low cost. However, use of oils and fat are highly adulterated resulting in high free fatty acid content which turn impacts on the efficiency of FAME production. Therefore, in light of the need to develop, alternative lipid feed stocks and related efficient catalysis the present study investigates the potential of producing renewable diesel from the lipids-extracted from activated sludge, a waste water treatment by-product, through catalytic hydrothermal decarboxylation. The microbial lipids were first extracted from the activated sludge using the Folch et al method before hydrothermal decarboxylation reactions were carried out using palladium (Pd/C) and platinum (Pt/C) on activated carbon as the catalysts in a batch reactor. The impact of three temperatures 290, 300, 330 °C and residence time between 30 min and 4hrs was assessed. At the end of the reaction, the products were recovered using organic solvents and characterized using gas chromatography (GC). The principle products of the reaction were pentadecane and heptadecane. The highest yields of pentadecane and heptadecane from lipid-extract were 23.23% and 15.21%, respectively. These yields were obtained at 290 °C and residence time 1h using Pt/C. To the best of our knowledge, the current work is the first investigation on the hydrothermal decarboxylation of lipid-extract from activated sludge.

Keywords: activated sludge, lipid, hydrothermal decarboxylation, renewable diesel

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Authors: Ghulam Abbas, Ikramul Haq, Ghulam Ghouse

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Bread wheat Triticum aestivum L. (Poaceae) is the major source of the staple food for a number of countries of the world including Pakistan. Since it is the staple food of the country, it has been desired, and efforts have been made, that it does not undergo application of pesticides to ensure the food safety. Luckily, wheat does not face a serious threat of insect pests, in ecological conditions of Pakistan, except aphids and armyworm which infest the wheat prior to maturity. It has been observed that almost 5 species of aphid have been reported to attack wheat ie. Ropalosiphum maidi, R. Padi, Schizaphis graminum, Diuraphis noxia, and Sitibion miscanthi but due to natural rise in temperature in terminal season of wheat, the population of aphid gradually decreases and wheat has a safe escape from its infestation. In case, mild temperatures 15ºC to 30ºC prolong, the infestation of aphids also prolongs and it can severely damage wheat in patches, and it has potential to substantially reduce the yield of wheat in infested patch. In years 2013, 2014, and 2015 the studies were undertaken to determine the potential of damage caused by aphid complex in 10 fields in infested patches. The damage caused by aphid complex was calculated on the basis of 1000 grain weight of wheat grains taken from the infested patch and were compared with 1000 grain weight of the healthy plants of the same fields. It was observed that there was 26 to 42% decrease in the weight of grain in infested patches. This patch also escaped from general harvesting by combine harvester and enhanced the loss 13 to 46%. The quality of the wheat straw was also reduced and its acceptance to the animals was also affected up to 50 to 100%. Moreover, the population of naturally existing beneficial fauna was recorded and factors promoting establishment and manipulation of beneficial fauna were studied and analysed.

Keywords: Triticum aestivum, wheat, Pakistan, beneficial fauna, aphid complex

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Authors: Kwasi Sarfo, Bernard Okoampah Otu

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The 1992 constitution of the Republic of Ghana recognises the authority and roles of traditional leaders and considers them as being entrusted with fiduciary responsibility over land in their respective territories. The new land act, Act 1036 of 2020, in buttressing the fiduciary role of traditional leaders in land matters, inserted the traditional leaders’ accountability clause. Many traditional leaders have expressed their misgivings about the insertion of this clause. Therefore, there appears to be a misunderstanding of the concept of fiduciary in land management in Ghana. The objective of this study is to examine the concept of fiduciary in respect of allodial rights holders in land management and administration and how this concept is perceived and applied by traditional leaders. The study seeks to provide insights into the discrepancy between fiduciary theory and its practical implementation in Ghana. The study is based on a qualitative empirical research approach and adopts in-depth interviews as a primary method of data collection. The study also adopts the theory of New Institutionalism of social anthropology in analysing and interpreting the findings. The data for this study was collected over a period of one year, from July 2022 to July 2023, as part of one of the author's PhD dissertation. The collected data were carefully analysed using the principles of thematic analysis, identifying key themes and patterns. This study does not seek to pursue the discussions from a legal standpoint but from a social anthropological perspective and argues that the concept of fiduciary in theory is far different from what pertains in practice and that traditional leaders’ assumptions and application of this concept contribute to the alienation of customary and communal land at the expense of their subjects. This study deepens our understanding of the continuous expropriation of communal landholders in many rural communities in Africa in the era of global land grabbing, which worsens their poverty levels. It also explains further the theory of new institutionalism of social anthropology by highlighting how the theory manifests in practice in the case of Ghana.

Keywords: fiduciary, customary land tenure, allodial rights, land alienation, communal land, Ghana

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Authors: V. D. Povolockiy, V. E. Roshchin, Y. Kapelyushin

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Smelting of copper matte is followed by production of a large amount of slag. This slag mostly contains silicates and can be utilized in a construction industry. In addition to silicates it also contains Fe; if the Fe content is high, the density of the silicate phases increases and such a slag cannot be used as an additive for the concrete. Furthermore, slags obtained during copper matte production contain copper, sulphur, zinc and some other elements. Fe is the element with the highest price in these slags. An extraction of Fe is possible even using the conventional methods, e.g., the addition of slag to the charge materials during production of sinter for the blast furnace smelting. However, in this case, the blast furnace hot metal would accumulate sulphur and copper which is very harmful impurity for the steelmaking. An accumulation of copper by the blast furnace hot metal is unacceptable, as copper cannot be removed during further steelmaking operations having a critical effect on the properties of steel. In present work, the technological scheme for non-waste utilization of the copper smelting slags has been suggested and experimentally confirmed. This scheme includes a solid state reduction of Fe and smelting for the separation of cast iron and slag. During solid state reduction, the zinc vapor was trapped. After the reduction and smelting operations, the cast iron containing copper was used for the production of metal balls with increased mechanical properties allowing their utilization for milling of ore minerals. Such a cast iron could also be applied in the production of special types of steel with copper. The silicate slag freed from Fe might be used as a propping agent in the oil industry, or granulated for application as an additive for concrete in a construction industry. Thereby, the suggested products for a Mini Mill plant with non-waste utilization of the copper smelting slags are cast iron grinding balls for the ore minerals, special types of steel with copper, silicate slag utilized as an additive for the concrete and propping agents for the oil industry.

Keywords: utilization of copper slag, cast iron, grinding balls, propping agents

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Authors: Tong Ming Liu

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Human mesenchymal stem cells (MSCs) represent the most used stem cells for clinical application, which have been used in over 1000 clinical trials to treat over 30 diseases due to multilineage differentiation potential, secretome and immunosuppression. Gene therapies of MSCs hold great promise in the treatment of many diseases due to enhanced MSC-based clinical outcomes. To identify genes for gene therapy of MSCs, by comparing gene expression profile before and after MSC differentiation following by functional screening, we have identified ZNF145 that regulated MSC differentiation. Forced expression of ZNF145 resulted in enhanced in vitro chondrogenesis of MSCs as an upstream factor of SOX9 and improved osteochondral repair upon implant into osteochondral defects in rodents. By comparing gene expression profile during differentiation of iPSCs toward MSCs, we also identified gene HOX regulating MSC stemness, which was much downregulated in late-passaged MSCs. Knockdown of this gene greatly compromised MSC stemness including abolished proliferation, decreased CFU-F, promoted senescence and reduced expression of cell surface antigens linked to the MSC phenotype. In addition, multi-linage differentiation was also greatly impaired. Notably, HOX overexpression resulted in improved multi-lineage differentiation. In the mechanism, HOX expression significantly deceased in late passage of MSCs compared with early passage of MSCs, correlating with MSC important genes. ChIP-seq data shown that HOX binds to genes related to MSC self-renewal and differentiation. Most importantly, most HOX binding sites are lost in late passage of MSCs. HOX exerts its effects by directing binding Twist1, one important gene of MSCs. The identification of the genes regulating MSC differentiation and stemness will provide and promising strategies for gene therapy of MSCs in regenerative medicine.

Keywords: mesenchymal stem cell, novel transcription factor, stemness, gene therapy, cartilage repair, signaling pathway

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Authors: Meenu Joshi, Natalie Naidoo, Farzeen Kader

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Identification of body fluids is an essential step in forensic investigation to aid in crime reconstruction. Tissue-specific differentially methylated regions (tDMRs) of the human genome can be targeted to be used as biomarkers to differentiate between body fluids. The present study was undertaken to establish the methylation status of potential tDMRs in blood, semen, saliva, and vaginal fluid by using methylation-specific PCR (MSP) and bisulfite sequencing (BS). The methylation statuses of 3 potential tDMRS in genes ZNF282, PTPRS, and HPCAL1 were analysed in 10 samples of each body fluid. With MSP analysis, the ZNF282, and PTPRS1 tDMR displayed semen-specific hypomethylation while HPCAL1 tDMR showed saliva-specific hypomethylation. With quantitative analysis by BS, the ZNF282 tDMR showed statistically significant difference in overall methylation between semen and all other body fluids as well as at individual CpG sites (p < 0.05). To evaluate the effect of environmental conditions on the stability of methylation profiles of the ZNF282 tDMR, five samples of each body fluid were subjected to five different forensic simulated conditions (dry at room temperature, wet in an exsiccator, outside on the ground, sprayed with alcohol, and sprayed with bleach) for 50 days. Vaginal fluid showed highest DNA recovery under all conditions while semen had least DNA quantity. Under outside on the ground condition, all body fluids except semen showed a decrease in methylation level; however, a significant decrease in methylation level was observed for saliva. A statistical significant difference was observed for saliva and semen (p < 0.05) for outside on the ground condition. No differences in methylation level were observed for the ZNF282 tDMR under all conditions for vaginal fluid samples. Thus, in the present study ZNF282 tDMR has been identified as a novel and stable semen-specific hypomethylation marker.

Keywords: body fluids, bisulphite sequencing, forensics, tDMRs, MSP

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Authors: Monika Benedek

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Improvisation is an integral part of music education programmes worldwide since teachers recognize that improvisation helps to broaden stylistic knowledge, develops creativity and various musical skills, in particular, aural skills, and also motivates to learn music theory. In Hungary, where Kodály concept is a core element of music teacher education, improvisation has been relatively neglected subject in both primary school and classical music school curricula. Therefore, improvisation was an important theme of a one-year-long research project carried out at the Liszt Academy of Music in Budapest. The project aimed to develop the music teacher training programme, and among others, focused on testing how improvisation could be used as a teaching tool to improve students’ musical reading and writing skills and creative musical skills. Teacher-researchers first tested various teaching approaches of improvisation with numerous teaching modules in music lessons at public schools and music schools. Data were collected from videos of lessons and from teachers’ reflective notes. After analysing data and developing teaching modules, all modules were tested again in a pilot course in 30 contact lessons for music teachers. Teachers gave written feedback of the pilot programme, tested two modules by their choice in their own teaching and wrote reflecting comments about their experiences in applying teaching modules of improvisation. The overall results indicated that improvisation could be an innovative approach to teaching various musical subjects, in particular, solfege, music theory, and instrument, either in individual or in group instruction. Improvisation, especially with the application of relative solmisation and singing, appeared to have been a beneficial tool to develop various musicianship skills of students and teachers, in particular, the aural, musical reading and writing skills, and creative musical skills. Furthermore, improvisation seemed to have been a motivating teaching tool to learn music theory by creating a bridge between various musical styles. This paper reports on the results of the research project.

Keywords: improvisation, Kodály concept, music school, public school, teacher training

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Authors: M. Ghosh, A. Miroux, L. A. I. Kestens

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At molecular or micrometre scale, practically all materials are neither homogeneous nor isotropic. The concept of texture is used to identify the structural features that cause the properties of a material to be anisotropic. For metallic materials, the anisotropy of the mechanical behaviour originates from the crystallographic nature of plastic deformation, and is therefore controlled by the crystallographic texture. Anisotropy in mechanical properties often constitutes a disadvantage in the application of materials, as it is often illustrated by the earing phenomena during drawing. However, advantages may also be attained when considering other properties (e.g. optimization of magnetic behaviour to a specific direction) by controlling texture through thermo-mechanical processing). Nevertheless, in order to have better control over the final properties it is essential to relate texture with materials processing route and subsequently optimise their performance. However, up to date, few studies have been reported about the evolution of texture in 6061 aluminium alloy during warm processing (from room temperature to 250ºC). In present investigation, recrystallized 6061 aluminium alloy samples were subjected to tensile and plane strain compression (PSC) at room and warm temperatures. The gradual change of texture following both deformation modes were measured and discussed. Tensile tests demonstrate the mechanism at low strain while PSC does the same at high strain and eventually simulate the condition of rolling. Cube dominated texture of the initial rolled and recrystallized AA6061 sheets were replaced by domination of S and R components after PSC at room temperature, warm temperature (250ºC) though did not reflect any noticeable deviation from room temperature observation. It was also noticed that temperature has no significant effect on the evolution of grain morphology during PSC. The band contrast map revealed that after 30% deformation the substructure inside the grain is mainly made of series of parallel bands. A tendency for decrease of Cube and increase of Goss was noticed after tensile deformation compared to as-received material. Like PSC, texture does not change after deformation at warm temperature though. n-fibre was noticed for all the three textures from Goss to Cube.

Keywords: AA 6061, deformation, temperature, tensile, PSC, texture

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Authors: R. Bužgová, R. Kozáková, M. Škutová, M. Bar, P. Ressner, P. Bártová

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Introduction: Currently, there has been an increasing concern about the provision of palliative care in non-oncological patients in both professional literature and clinical practice. However, there is not much scientific information on how to provide neurological and palliative care together. The main objective of the project is to create and to verify a concept of neuro-palliative and rehabilitative care for patients with selected neurological diseases in an advanced stage of the disease and also to evaluate bio-psychosocial and spiritual needs of these patients and their caregivers related to the quality of life using created standardized tools. Methodology: Triangulation of research methods (qualitative and quantitative) will be used. A concept of care and assessment tools will be developed by analyzing interviews and focus groups. Qualitative data will be analyzed using grounded theory. The concept of care will be tested in the context of the intervention study. Using quantitative analysis, we will assess the effect of an intervention provided on the saturation of needs, quality of life, and quality of care. A research sample will be made up of the patients with selected neurological diseases (Parkinson´s syndrome, motor neuron disease, multiple sclerosis, Huntington’s disease), together with patients´ family members. Based on the results, educational materials and a certified course for health care professionals will be created. Findings: Based on qualitative data analysis, we will propose the concept of integrated care model combining neurological, rehabilitative and specialist palliative care for patients with selected neurological diseases in different settings of care and services. Patients´ needs related to quality of life will be described by newly created and validated measuring tools before the start of intervention (application of neuro-palliative and palliative approach) and then in the time interval. Conclusion: Based on the results, educational materials and a certified course for doctors and health care professionals will be created.

Keywords: multidisciplinary approach, neuropalliative care, research, quality of life

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Authors: Hamidreza Mansouri

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In the construction industry, the lifespan of a metal structure is directly related to the quality of welding. In most metal structures, the welded area is considered critical and is one of the most important factors in design. To date, many fracture incidents caused by these types of cracks have occurred. Various methods exist to increase the lifespan of welds to prevent failure in the welded area. Among these methods, the application of ultrasonic peening, in addition to the stress relief process, can manually and more precisely adjust the geometry of the weld toe and prevent stress concentration in this part. This research examined Gas Tungsten Arc Welding (GTAW) on common structural steels and 316 stainless steel, which require precise welding, to predict the optimal condition. The GTAW method was used to create residual stress; two samples underwent ultrasonic stress relief, and for comparison, two samples underwent thermal stress relief. Also, no treatment was considered for two samples. The residual stress of all six pieces was measured by X-Ray Diffraction (XRD) method. Then, the two ultrasonically stress-relieved samples and two untreated samples were exposed to a corrosive environment to initiate cracking and determine the effectiveness of the ultrasonic stress relief method. Thus, the residual stress caused by GTAW in the samples decreased by 3.42% with thermal treatment and by 7.69% with ultrasonic peening. Furthermore, the results show that the untreated sample developed cracks after 740 hours, while the ultrasonically stress-relieved piece showed no cracks. Given the high costs of welding and post-welding zone modification processes, finding an economical, effective, and comprehensive method that has the least limitations alongside a broad spectrum of usage is of great importance. Therefore, the impact of various ultrasonic peening stress relief parameters and the selection of the best stress relief parameter to achieve the longest lifespan for the weld area is highly significant.

Keywords: GTAW welding, stress corrosion cracking(SCC), thermal method, ultrasonic peening.

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Authors: Ramzi Suleiman

Abstract:

Recently, the author proposed an observationally-based relativity theory termed information relativity theory (IRT). The theory is simple and is based only on basic principles, with no prior axioms and no free parameters. For the case of a body of mass in uniform rectilinear motion relative to an observer, the theory transformations uncovered a matter-dark matter duality, which prescribes that the sum of the densities of the body's baryonic matter and dark matter, as measured by the observer, is equal to the body's matter density at rest. It was shown that the theory transformations were successful in predicting several important phenomena in small particle physics, quantum physics, and cosmology. This paper extends the theory transformations to the cases of rotating disks and spheres. The resulting transformations for a rotating disk are utilized to derive predictions of the radial distributions of matter and dark matter densities in rotationally supported galaxies based solely on their observed rotation curves. It is also shown that for galaxies with flattening curves, good approximations of the radial distributions of matter and dark matter and of the dark matter fraction could be obtained from one measurable scale radius. Test of the model on five galaxies, chosen randomly from the SPARC database, yielded impressive predictions. The rotation curves of all the investigated galaxies emerged as accurate traces of the predicted radial density distributions of their dark matter. This striking result raises an intriguing physical explanation of gravity in galaxies, according to which it is the proximal drag of the stars and gas in the galaxy by its rotating dark matter web. We conclude by alluding briefly to the application of the proposed model to stellar systems and black holes. This study also hints at the potential of the discovered matter-dark matter duality in fixing the standard model of elementary particles in a natural manner without the need for hypothesizing about supersymmetric particles.

Keywords: dark matter, galaxies rotation curves, SPARC, rotating disk

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