Search results for: water ways

Authors: Robin Devillers, Chantal van Dijk

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Children face ambiguities in everyday language use. Particularly ambiguity in pronoun resolution can be challenging, whereas adults can rapidly identify the antecedent of the mentioned pronoun. Two main factors underlie this process, namely the accessibility of the referent and the syntactic cues of the pronoun. After 200ms, adults have converged the accessibility and the syntactic constraints, while relieving cognitive effort by considering contextual cues. As children are still developing their cognitive capacity, they are not able yet to simultaneously assess and integrate accessibility, contextual cues and syntactic information. As such, they fail to identify the correct referent and possibly fixate more on the competitor in comparison to adults. In this study, Dutch while-clauses were used to investigate the interpretation of pronouns by children. The aim is to a) examine the extent to which 7-10 year old children are able to utilise discourse and syntactic information during online and offline sentence processing and b) analyse the contribution of individual factors, including age, working memory, condition and vocabulary. Adult and child participants are presented with filler-items and while-clauses, and the latter follows a particular structure: ‘Anna and Sophie are sitting in the library. While Anna is reading a book, she is taking a sip of water.’ This sentence illustrates the ambiguous situation, as it is unclear whether ‘she’ refers to Anna or Sophie. In the unambiguous situation, either Anna or Sophie would be substituted by a boy, such as ‘Peter’. The pronoun in the second sentence will unambiguously refer to one of the characters due to the syntactic constraints of the pronoun. Children’s and adults’ responses were measured by means of a visual world paradigm. This paradigm consisted of two characters, of which one was the referent (the target) and the other was the competitor. A sentence was presented and followed by a question, which required the participant to choose which character was the referent. Subsequently, this paradigm yields an online (fixations) and offline (accuracy) score. These findings will be analysed using Generalised Additive Mixed Models, which allow for a thorough estimation of the individual variables. These findings will contribute to the scientific literature in several ways; firstly, the use of while-clauses has not been studied much and it’s processing has not yet been identified. Moreover, online pronoun resolution has not been investigated much in both children and adults, and therefore, this study will contribute to adults and child’s pronoun resolution literature. Lastly, pronoun resolution has not been studied yet in Dutch and as such, this study adds to the languages

Keywords: pronouns, online language processing, Dutch, eye-tracking, first language acquisition, language development

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Authors: Manar Amayri, Hussain Kazimi, Quoc-Dung Ngo, Stephane Ploix

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A general approach is proposed to determine occupant behavior (occupancy and activity) in residential buildings and to use these estimates for improved energy management. Occupant behaviour is modelled with a Bayesian Network in an unsupervised manner. This algorithm makes use of domain knowledge gathered via questionnaires and recorded sensor data for motion detection, power, and hot water consumption as well as indoor CO₂ concentration. Two case studies are presented which show the real world applicability of estimating occupant behaviour in this way. Furthermore, experiments integrating occupancy estimation and hot water production control show that energy efficiency can be increased by roughly 5% over known optimal control techniques and more than 25% over rule-based control while maintaining the same occupant comfort standards. The efficiency gains are strongly correlated with occupant behaviour and accuracy of the occupancy estimates.

Keywords: energy, management, control, optimization, Bayesian methods, learning theory, sensor networks, knowledge modelling and knowledge based systems, artificial intelligence, buildings

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Authors: Chaoran Liu

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Bioactive polysaccharides and polysaccharide-protein complex derived from mushrooms and fungi have a wide range of immunomodulatory activity with low side-effects and have therefore the potential to be developed as an adjuvant in cancer therapies. Mushrooms sclerotium is rich in polysaccharides and the polysaccharides isolated from the sclerotium of Polyporus rhinocerus have shown potent in vivo and in vitro immunomodulatory effects. Macrophages are considered to be an important component of the innate immune response against bacterial infection and cancer. To better understanding the immunomodulatory effects and its underlying mechanisms of sclerotial water-soluble polysaccharides extracted from P. rhinocerus on macrophages, the objectives of this study are to purify the water-soluble novel sclerotial polysaccharides and to characterize the structure and properties as well as to study the detailed molecular mechanisms of the in vitro immunomodulating effects in murine macrophages. The hot water-soluble fraction PRW from the sclerotium of P. rhinocerus was obtained using solvent extraction. PRW was further fractionated by membrane ultrafiltration to a give a fraction (PRW1) with molecular mass less than 50 kDa. PRW1 was characterized to be a polysaccharide-protein complex composed of 45.7% polysaccharide and 44.2% protein. The chemical structure of the carbohydrate moiety of PRW1 was elucidated by GC and FTIR to be mainly beta-D-glucan with trace amount of galactose and mannose. The immunomodulatory effects of PRW1 on murine RAW 264.7 macrophages were demonstrated in terms of the increase in nitric oxide production and cytokine production. Mechanistically, PRW1 initiates ERK phosphorylation to activate macrophages within 15 min and significantly improves the expression level of inducible NOS (iNOS) from 6 h after treatment. In summary, this study indicates that PRW1 is a potent immunomodulatory agent for macrophages and suggests that mushroom sclerotia from Polyporus rhinocerus requires for further investigation in cancer research.

Keywords: Polyporus rhinocerus, mushroom sclerotia, Polysaccharide-Protein Complex, macrophage activation

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Authors: U.K. Sarkar, G. Karnatak, P. Mishal, Lianthuamluaia, S. Kumari, S.K. Das, B.K. Das

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Inland open water fisheries provide food, income, livelihood and nutritional security to millions of fishers across the globe. However, the open water ecosystem and fisheries are threatened due to climate change and anthropogenic pressures, which are more visible in the recent six decades, making the resources vulnerable. Understanding the interaction between meteorological parameters and inland fisheries is imperative to develop mitigation and adaptation strategies. As per IPCC 5th assessment report, the earth is warming at a faster rate in recent decades. Global mean surface temperature (GMST) for the decade 2006–2015 (0.87°C) was 6 times higher than the average over the 1850–1900 period. The direct and indirect impacts of climatic parameters on the ecology of fisheries ecosystem have a great bearing on fisheries due to alterations in fish physiology. The impact of meteorological factors on ecosystem health and fish food organisms brings about changes in fish diversity, assemblage, reproduction and natural recruitment. India’s average temperature has risen by around 0.7°C during 1901–2018. The studies show that the mean air temperature in the Ganga basin has increased in the range of 0.20 - 0.47 °C and annual rainfall decreased in the range of 257-580 mm during the last three decades. The studies clearly indicate visible impacts of climatic and environmental factors on inland open water fisheries. Besides, a significant reduction in-depth and area (37.20–57.68% reduction), diversity of natural indigenous fish fauna (ranging from 22.85 to 54%) in wetlands and progression of trophic state from mesotrophic to eutrophic were recorded. In this communication, different applications of biometeorology in inland fisheries management with special reference to the assessment of ecosystem and species vulnerability to climatic variability and change have been discussed. Further, the paper discusses the impact of climate anomaly and extreme climatic events on inland fisheries and emphasizes novel modeling approaches for understanding the impact of climatic and environmental factors on reproductive phenology for identification of climate-sensitive/resilient fish species for the adoption of climate-smart fisheries in the future. Adaptation and mitigation strategies to enhance fish production and the role of culture-based fisheries and enclosure culture in converting sequestered carbon into blue carbon have also been discussed. In general, the type and direction of influence of meteorological parameters on fish biology in open water fisheries ecosystems are not adequately understood. The optimum range of meteorological parameters for sustaining inland open water fisheries is yet to be established. Therefore, the application of biometeorology in inland fisheries offers ample scope for understanding the dynamics in changing climate, which would help to develop a database on such least, addressed research frontier area. This would further help to project fisheries scenarios in changing climate regimes and develop adaptation and mitigation strategies to cope up with adverse meteorological factors to sustain fisheries and to conserve aquatic ecosystem and biodiversity.

Keywords: biometeorology, inland fisheries, aquatic ecosystem, modeling, India

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Authors: Ali Etemadi, Claudia Fernanda Yasar

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Elevated water storage tank structures (EWSTs) are high elevated-ponderous structural systems and very vulnerable to seismic vibrations. In past earthquake events, many of these structures exhibit poor performance and experienced severe damage. The dynamic analysis of the EWSTs under earthquake loads is, therefore, of significant importance for the design of the structure and a key issue for the development of modern methods, such as active control design. In this study, a reduced model of the EWSTs is explained, which is based on a tuned mass damper model (TMD). Vibration analysis of a structure under seismic excitation is presented and then used to propose an active vibration controller. MATLAB/Simulink is employed for dynamic analysis of the system and control of the seismic response. A single degree of freedom (SDOF) and two degree of freedom (2DOF) models of ELSTs are going to be used to study the concept of active vibration control. Lab-scale experimental models similar to pendulum are applied to suppress vibrations in ELST under seismic excitation. One of the most important phenomena in liquid storage tanks is the oscillation of fluid due to the movements of the tank body because of its base motions during an earthquake. Simulation results illustrate that the EWSTs vibration can be reduced by means of an input shaping technique that takes into account the dominant mode shape of the structure. Simulations with which to guide many of our designs are presented in detail. A simple and effective real-time control for seismic vibration damping can be, therefore, design and built-in practice.

Keywords: elevated water storage tank, tuned mass damper model, real time control, shaping control, seismic vibration control, the laplace transform

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Authors: Dimitra Riza

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This paper examines different ways of exploring a city by using smart phones' applications while walking, and the way this new attitude will change our perception of the urban environment. By referring to various examples of such applications we will consider options and possibilities that open up with new technologies, their advantages and disadvantages, as well as ways of experiencing and interpreting the urban environment. The widespread use of smart phones gave access to information, maps, knowledge, etc. at all times and places. The city tourism marketing takes advantage of this event and promotes the city's attractions through technology. Mobile mediated walking tours, provide new possibilities and modify the way we used to explore cities, for instance by giving directions proper to find easily destinations, by displaying our exact location on the map, by creating our own tours through picking points of interest and interconnecting them to create a route. These apps act as interactive ones, as they filter the user's interests, movements, etc. Discovering a city on foot and visiting interesting sites and landmarks, became very easy, and has been revolutionized through the help of navigational and other applications. In contrast to the re-invention of the city as suggested by the Baudelaire's Flâneur in the 19th century, or to the construction of situations by the Situationists in 60s, the new technological means do not allow people to "get lost", as these follow and record our moves. In the case of strolling or drifting around the city, the option of "getting lost" is desired, as the goal is not the "wayfinding" or the destination, but it is the experience of walking itself. Getting lost is not always about dislocation, but it is about getting a feeling, free of the urban environment while experiencing it. So, on the one hand, walking is considered to be a physical and embodied experience, as the observer becomes an actor and participates with all his senses in the city activities. On the other hand, the use of a screen turns out to become a disembodied experience of the urban environment, as we perceive it in a fragmented and distanced way. Relations with the city are similar to Alberti’s isolated viewer, detached from any urban stage. The smartphone, even if we are present, acts as a mediator: we interact directly with it and indirectly with the environment. Contrary to the Flaneur and to the Situationists, who discovered the city with their own bodies, today the body itself is being detached from that experience. While contemporary cities turn out to become more walkable, the new technological applications tend to open out all possibilities in order to explore them by suggesting multiple routes. Exploration becomes easier, but Perception changes.

Keywords: body, experience, mobile apps, walking

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Authors: Glykeria A. Visvini, George Ν. Mathioudakis, Amaia Soto Beobide, George A. Voyiatzis

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Polymer nanocomposites are materials in which a polymer matrix is reinforced with nanoscale inclusions, such as nanoparticles, nanoplates, or nanofibers. These nanoscale inclusions can significantly enhance the mechanical, thermal, electrical, and other properties of the polymer matrix, making them attractive for a wide range of industrial applications. These properties can be tailored by adjusting the type and the concentration of the nanoinclusions, which provides a high degree of flexibility in their design and development. An important property that polymeric membranes can exhibit is water vapor permeability (WVP). This can be accomplished by various methods, including the incorporation of micro/nano-fillers into the polymer matrix. In this way, a micro/nano-pore network can be formed, allowing water vapor to permeate through the membrane. At the same time, the membrane can be stretched uni- or bi-axially, creating aligned or cross-linked micropores in the composite, respectively, which can also increase the WVP. Nowadays, in industry, stretched films reinforced with CaCO3 develop micro-porosity sufficient to give them breathability characteristics. Carbon-based nanomaterials, such as graphene oxide (GO), are tentatively expected to be able to effectively improve the WVP of corresponding composite polymer films. The presence in the GO structure of various functional oxidizing groups enhances its ability to attract and channel water molecules, exploiting the unique large surface area of graphene that allows the rapid transport of water molecules. Polypropylene (PP) is widely used in various industrial applications due to its desirable properties, including good chemical resistance, excellent thermal stability, low cost, and easy processability. The specific properties of PP are highly influenced by its crystalline behavior, which is determined by its processing conditions. The development of the β-crystalline phase in PP, in combination with stretching, is anticipating improving the microporosity of the polymer matrix, thereby enhancing its WVP. The aim of present study is to create breathable PP composite membranes using carbon-based nanomaterials, such as graphene oxide (GO), reduced graphene oxide (rGO), and graphene nanoplatelets (GNPs). Unlike traditional methods that rely on the drawing process to enhance the WVP of PP, this study intents to develop a low-cost approach using melt mixing with β-nucleating agents and carbon fillers to create highly breathable PP composite membranes. The study aims to investigate how the concentration of these additives affects the water vapor transport properties of the resulting PP films/membranes. The presence of β-nucleating agents and carbon fillers is expected to enhance β-phase growth in PP, while an alternation between β- and α-phase is expected to lead to improved microporosity and WVP. Our ambition is to develop highly breathable PP composite films with superior performance and at a lower cost compared to the benchmark. Acknowledgment: This research has been co‐financed by the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation, under the call «Special Actions "AQUACULTURE"-"INDUSTRIAL MATERIALS"-"OPEN INNOVATION IN CULTURE"» (project code: Τ6YBP-00337)

Keywords: carbon based nanomaterials, nanocomposites, nucleating agent, polypropylene, water vapor permeability

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Authors: X. Li, Y. Liu, H. Wong, B. Pardoen, A. Fabbri, F. McGregor, E. Liu

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The target of this paper is to investigate how saturated poroelastic soils subject to freezing temperatures behave and how different boundary conditions can intervene and affect the thermo-hydro-mechanical (THM) responses, based on a particular but classical configuration of a finite homogeneous soil layer studied by Terzaghi. The essential relations on the constitutive behavior of a freezing soil are firstly recalled: ice crystal - liquid water thermodynamic equilibrium, hydromechanical constitutive equations, momentum balance, water mass balance, and the thermal diffusion equation, in general, non-linear case where material parameters are state-dependent. The system of equations is firstly linearized, assuming all material parameters to be constants, particularly the permeability of liquid water, which should depend on the ice content. Two analytical solutions solved by the classic Laplace transform are then developed, accounting for two different sets of boundary conditions. Afterward, the general non-linear equations with state-dependent parameters are solved using a commercial code COMSOL based on finite elements method to obtain numerical results. The validity of this numerical modeling is partially verified using the analytical solution in the limiting case of state-independent parameters. Comparison between the results given by the linearized analytical solutions and the non-linear numerical model reveals that the above-mentioned linear computation will always underestimate the liquid pore pressure and displacement, whatever the hydraulic boundary conditions are. In the nonlinear model, the faster growth of ice crystals, accompanying the subsequent reduction of permeability of freezing soil layer, makes a longer duration for the depressurization of water liquid and slower settlement in the case where the ground surface is swiftly covered by a thin layer of ice, as well as a bigger global liquid pressure and swelling in the case of the impermeable ground surface. Nonetheless, the analytical solutions based on linearized equations give a correct order-of-magnitude estimate, especially at moderate temperature variations, and remain a useful tool for preliminary design checks.

Keywords: chemical potential, cryosuction, Laplace transform, multiphysics coupling, phase transformation, thermodynamic equilibrium

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Authors: Ahmed Bolaji Alarape, Oluwatobi Damilola Aba, Usman Shehu

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Wood plastic composite boards were made from sawn dust of Cordia alliodora and recycled polyethylene at a mixing ratio of 1.5ratio1, 2.5ratio1 and 3.5ratio1 and nominal densities of 600 kilograms per meter cube, 700 kilograms per meter cube, and 800 kilograms per meter cube, The material was hot pressed at 150-degree celsius to produce board of 250 millimeter by 250 millimeter by 6 millimeter of which 18 boards were produced. The experiment was subject to 3 by 3 factorial experiments in Completely Randomised Design (CRD). Analysis of variance and Duncan Multiple Range Test (DMRT) was adopted by 3 by 3 at 5 percent probability. The strength properties of the boards such as modulus of rupture (MOR) and modulus of elasticity (MOE) were investigated, while the dimensional properties of the board such as the water absorption (WA) and thickness swelling (TS) were as well determined after 12hrs and 24hrs of water immersion. The result showed that the mean values of MOE ranged from 9100.73 Newtons per square millimeters to 12086.96 Newtons per square millimeters while MOR values ranged from 48.26 Newtons per square millimeters to 103.09 Newtons per square millimeters. The values of WA and TS after 12hrs immersion ranged from 1.21 percent to 1.56 percent and 0.00 percent to 0.13 percent, respectively. The values of WA and TS after 24hrs of water immersion ranged from 1.66 percent to 2.99 percent and 0.02 percent to 0.18 percent, respectively. The higher the value of board density and the high-density polythene /sawdust ratio, the stronger, the stiffer and more dimensionally stable the wood plastic composite boards obtained. In addition, as the density of the board increases, the strength property of the boards increases. Hence the board will be suitable for internal construction materials.

Keywords: wood Plastic composite, modulus of rupture, modulus of elasticity, dimensional stability

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Authors: Nikolaos Souvlakis

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One of the prominent phenomena that have survived even in the 21st century, when science is gaining more and more space in the scientific world, is the evil eye within non-Westernized societies and more specifically in Greek culture. The presentation is based on the Christian Orthodox beliefs and folklore about the evil eye. Evil eye occupies an important role in individuals' everyday life and it is fuelled by Satanic powers. Satanic powers and the belief on them have an immense effect on individual's well-being and mental health causing spiritual suffering. The present paper examines the psychological manifestations of the belief of evil eye in individuals' mental health and the ways to protect from it according to the Greek Orthodox tradition.

Keywords: spirituality, belief, evil eye, mental health, well-being, healing

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Authors: Abdelmagid Basyouny Sakr

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Terminological variation is a reality and it is now recognized by terminologists. This paper investigates the terminological variation in the context of specialized economic texts in Italian. It aims to find whether certain patterns or tendencies can be derived from the analysis of these texts. Term variants pose two different kinds of difficulties. The first one is being able to recognize linguistic expressions that denote the same concept in running text. Another one lies in knowing which variant should be considered and for what purpose. This would help to differentiate between variants that could be candidates for inclusion in terminological resources and the ones which are synonyms or contextual variants. New insights about terminological variation in specialized texts could contribute to improve specialized dictionaries which will better account for the different ways in which a given thought is expressed.

Keywords: corpus linguistics, specialized communication, terms and concepts, terminological variation

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Authors: Bilha Paryente, Rivi Frei Landau

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Autoethnography - a combination of autobiography and ethnography - focuses on the intersection of personal experiences and the culture in which they take place and is considered a viable method for exploring human experiences. The Russo-Ukrainian war has resulted in millions of forcibly displaced asylum-seeking refugees facing ambiguous loss. Whereas much is known about refugees' support needs, little is known about the needs and experiences of the humanitarian delegation members (HDM) who assist them. Through a debrief-based co-autoethnographic account of a female HDM who supported Ukrainian refugee mothers and children on the Polish borders, we explored the lived experiences involved in such a mission. Specifically, we conducted a transnational dyadic autoethnography debrief-based co-autoethnography which included both verbal and photo-based debriefing (8 two-hour sessions) alongside a reflexive (10-day) field diary analysis. Content analysis revealed cognitive dilemmas, emotional struggles, and practical adaptations occurring within the HDM's three identity-related domains: personal, professional (psychologist), and ethnic. The methodology presented and demonstrated in this paper enhances our theoretical understanding of the challenges faced by HDMs and may contribute to better future design of HDM training. Practically, the findings of the current study suggest the need for a three-stage accompaniment for HDMs relating to their personal, professional, and ethnic identities and considering their cognitive, emotional, and adaptive aspects. First, before leaving, HDMs should be briefed on personal and professional aspects of their experiences and ways of coping with them, as well as ethnic and religious affiliation issues. Second, while volunteering every evening their dilemmas, emotional struggles, and ways of adapting should be addressed for the three layers of identities. And finally, shortly after their return, there should be a final meeting to discuss all aspects of their identities and layers of personality. In this way, HDMs can become more effective in the important mission they fulfill. We hope that future HDMs and the bodies that send them on humanitarian missions of paramount importance will adopt these recommendations and generate proactive insights for members of future delegations.

Keywords: autoethnography, refugees, humanitarian delegation, ambiguous loss, Russo-Ukraine War, parenting

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Authors: Vladimir A. Rozov

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Comparative studies of religion and ritual could contribute better understanding of human culture universalities. Belief in supernatural beings seems to be a common feature of the religion. A significant part of the Islamic concepts that concern supernatural beings is based on a tradition based on the Hadiths. They reflect, among other things, his ideas about a proper way to interact with supernatural beings. These ideas to a large extent follow from the pre-Islamic religious experience of the Arabs and had been reflected in a number of ritual actions. Some of those beliefs concern a particular function of clothing. For example, it is known that Muhammad was wrapped in clothes during the revelation of the Quran. The same thing was performed by pre-Islamic soothsayers (kāhin) and by rival opponents of Muhammad during their trances. Muhammad also turned the clothes inside out during religious rituals (prayer for rain). Besides these specific ways of clothing which prove the external similarity of Muhammad with the soothsayers and other people who claimed the connection with supernatural forces, the pre-Islamic soothsayers had another characteristic feature which is physical flaws. In this regard, it is worth to note Muhammad's so-called "Seal the Prophecy" (h̠ ātam an- nubūwwa) -protrusion or outgrowth on his back. Another interesting feature of Muhammad's behavior was his attitude to eating onion and garlic. In particular, the Prophet didn`t eat them and forbade people who had tasted these vegetables to enter mosques, until the smell ceases to be felt. The reason for this ban on eating onion and garlic is caused by a belief that the smell of these products prevents communication with otherworldly forces. The materials of the Hadith also suggest that Muhammad shared faith in the apotropical properties of water. Both of these ideas have parallels in other cultures of the world. Muhammad's actions supposed to provide an interaction with the supernatural beings are not accidental. They have parallels in the culture of pre-Islamic Arabia as well as in many past and present world cultures. The latter fact can be explained by the similarity of the universal human beliefs in supernatural beings and how they should be interacted with. Later a number of similar ideas shared by the Prophet Muhammad was legitimized by the Islamic tradition and formed the basis of popular Islamic rituals. Thus, these parallels emphasize the commonality of human notions of supernatural beings and also demonstrate the significance of the pre-Islamic cultural context in analyzing the genesis of Islamic religious beliefs.

Keywords: hadith, Prophet Muhammad, ritual, supernatural beings

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Authors: Priti Rani, Rajni Johar, P. S. Jassal

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The magnetic chitosan beads (MCB) were synthesized using co-precipitation method and made to react with epichlorohydrin (ECH) to get the cross-linked derivative (ECH-MCB). The beads were characterized by FTIR, SEM, EDX, and TGA. It is found that zinc metal ion sorption efficiency of ECH-MCB is significantly higher than MCB. Various factors affecting the uptake behavior of metal ions, such as pH, adsorbent dosage, contact time, and temperature effects, were investigated. The adsorption parameters fitted well with Langmuir and Freundlich isotherms. The equilibrium parameter RL values support that the adsorption (0 < RL < 1) is favorable and spontaneous process. The thermodynamic parameters confirm that it is an endothermic reaction, which results in an increase in the randomness of adsorption process. The beads were regenerated using ethylene diamine tetraacetic acid (EDTA) for further use. These beads prove as promising materials for the removal of pollutants from industrial wastewater. Water samples from Yamuna and Hindon rivers were analysed for the detection of Zn (II) ions.

Keywords: chitosan magnetic beads, EDTA, epichlorohydrin, removal efficiency

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Authors: Salim Ahmed

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Electrocoagulation has proven its effectiveness in industrial effluent treatment by eliminating pollutants, particularly metallic ones. The electrochemical processes that occur at aluminium electrodes give excellent performance. In this work, electrocoagulation tests were carried out on an industrial effluent from an electroplating bath located in Casablanca (Morocco). The aim was to remove chromium and reuse the purified water for other purposes within the company. To this end, we have optimised the operating parameters that affect the efficiency of electrocoagulation, such as electrical voltage, electrode material, stirring speed and distance between electrodes. We also evaluated these parameters. The effect on pH, conductivity, turbidity and chromium concentration. The tests were carried out in a perfectly stirred reactor on an industrial solution rich in chromium. The effluent concentration was 1000 mg/L of Cr6+. Chromium removal efficiency was determined for the following operating conditions: aluminium electrodes, regulated voltage of 6 volts and 12 volts, optimum stirring speed of 600 rpm and distance between electrodes of 2 cm. The sludge produced by electrocoagulation was characterised by X-ray diffractometry, infrared spectroscopy (IR) and scanning electron microscopy (SEM).

Keywords: wastewater, chromium, electrocoagulation, aluminium, aluminium hydroxide

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Authors: Fatbardha Kadiu, Nulifer Caliskan

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The value added tax came as a necessity of substituting the old tax on sales. Based on the advantages of this new tax in our days it is used successfully in more than 140 countries around the world. The aim of the paper is to describe the nature of this tax with its advantages and disadvantages. Also it will describe the way how it functions in most of the European countries and the actual challenges of these countries on value added tax. It will be present the types of goods which are exempt from this tax, the reasons and the consequences of those exemptions. The paper will be based on secondary data taken from respective literature. An econometric model will be present in order to identify the dependence of value tax from other parameters. The analyzing most refers to the two main principles of harmonization and billing on the fiscal system and the ways how to restructures the system in order to minimize the fiscal evasion.

Keywords: value added tax, revenues, complexity, legal uncertainty

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Authors: Isabella B. Davidman

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Violence used against Jewish women in both the Eastern European pogroms and during the Nazi era was specifically gendered, targeting their female identity and dignity of womanhood. Not only did these acts of gendered violence dehumanize Jewish women, but they also hurt the Jewish community as a whole. The devastating sexual violence that women endured during the pogroms and the Nazi era caused profound trauma. Out of shame and fear, silence about women’s experiences of sexual abuse manifests in forms that words cannot translate. Women have turned to art and other means of storytelling to convey their female experiences in visual and non-verbal ways. Therefore, this paper aims to address the historical accounts of gendered violence against Jewish women during the pogroms and Nazi era, as well as art that reflects upon the female experience, in order to understand the emotional impact resulting from these events. To analyze the artwork, a feminist analysis was used to understand the intersection of gender with the other systems of inequality, such as systemic anti-semitism, in women’s lives; this ultimately explained the ways in which cultural productions undermine and reinforce the political and social oppression of women by exploring how art confronts the exploitation of women's bodies. By analyzing the art in the context of specific acts of violence, such as public rape, as a strategic weapon, we are able to understand women’s experiences and how these experiences, in turn, challenged their womanhood. Additionally, these atrocities, which often occurred in the public space, were dismissed and forgotten due to the social stigma of rape. In this sense, the experiences of women in pogroms and the Nazi era were both highly unacknowledged and forgotten. Therefore, the art that was produced during those time periods, as well as those after those events, gives voice to the profound silence on the narratives of Jewish women. Sexual violence is a weapon of war used to cause physical and psychological destruction, not only as a product of war. In both the early twentieth-century pogroms and the Holocaust, the sexual violence that Jewish women endured was fundamentally the same: the rape of Jewish women became a focal target in the theater of violence– women were not raped because they were women, but specifically, because they were Jewish women. Although the events of the pogroms and the Holocaust are in the past, the art that serves as testimony to the experience of Jewish women remains an everlasting reminder of the gendered violence that occurred. Even though covert expressions, such as an embroidered image of a bird eating an apple, the artwork gives voice to the many silenced victims of sexualized and gendered violence.

Keywords: gendered violence, holocaust, Nazi era, pogroms

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Authors: Hatem I. Mokhtar, Randa A. Abd-El-Salam, Ghada M. Hadad

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An improved nano-composite of self-doped polyaniline nanofibers and silica-coated magnetite nanoparticles were prepared and evaluated for suitability to magnetic dispersive micro solid-phase extraction. The work focused on optimization of the composite capacity to extract four fluoroquinolones (FQs) antibiotics, ciprofloxacin, enrofloxacin, danofloxacin, and difloxacin from water and improvement of composite stability towards acid and atmospheric degradation. Self-doped polyaniline nanofibers were prepared by oxidative co-polymerization of aniline with anthranilic acid. Magnetite nanopariticles were prepared by alkaline co-precipitation and coated with silica by silicate hydrolysis on magnetite nanoparticles surface at pH 6.5. The composite was formed by self-assembly by mixing self-doped polyaniline nanofibers with silica-coated magnetite nanoparticles dispersions in ethanol. The composite structure was confirmed by transmission electron microscopy (TEM). Self-doped polyaniline nanofibers and magnetite chemical structures were confirmed by FT-IR while silica coating of the magnetite was confirmed by Energy Dispersion X-ray Spectroscopy (EDS). Improved stability of the composite magnetic component was evidenced by resistance to degrade in 2N HCl solution. The adsorption capacity of self-doped polyaniline nanofibers based composite was higher than previously reported corresponding composite prepared from polyaniline nanofibers instead of self-doped polyaniline nanofibers. Adsorption-pH profile for the studied FQs on the prepared composite revealed that the best pH for adsorption was in range of 6.5 to 7. Best extraction recovery values were obtained at pH 7 using phosphate buffer. The best solvent for FQs desorption was found to be 0.1N HCl in methanol:water (8:2; v/v) mixture. 20 mL of Spiked water sample with studied FQs were preconcentrated using 4.8 mg of composite and resulting extracts were analysed by HPLC-UV method. The prepared composite represented a suitable adsorbent phase for magnetic dispersive micro-solid phase application.

Keywords: fluoroquinolones, magnetic dispersive micro extraction, nano-composite, self-doped polyaniline nanofibers

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Authors: Moses Mncwabe

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Both Public Representatives and Legislatures have an imperative role towards strengthening interventions to reduce and cease Sexual Transmitted Infections (STIs) specifically the Human Immunodeficiency Virus (HIV). Scaling-up constituency work in support of interventions earmarked for mitigating the compromising socio-economic impacts of advanced HIV is extremely essential. Though the antiretroviral treatment (ART) has saved million lives that would have perished without it, the Joint United Nations Programme on HIV/AIDS (2012) states that more efforts should be redirected to prevention strategies to close the tap of new infections. It is against this backdrop that Legislatures as law making institutions have undisputed role to play in HIV alleviation because of the position they occupy in the society. Furthermore, Public Representatives are arguably idolised by young people for the role they play hence it is incumbent upon them to use their moral and political responsibility to aid the interventions for HIV prevention (Inter-Parliamentary Union, Joint United Nations Programme on HIV/AIDS & United Nations Development Programme, 2007). Moreover, the continuous HIV infection and its devastating effects specifically in Southern African region has brought closer the disease to public representatives and demanded calculated interventions warranting both public representatives and legislatures to be more visible in various ways such as taking HIV counselling and testing publicly, oversight, reducing stigma and discrimination, partnering with civil society organisations (CSOs) and facilitating debates on HIV across parliamentary and social platforms. The effects of advanced HIV yearn for public representatives to be seen, accessed, felt, engaged, partnered and lobbied for pro-human rights legislations and ideal oversight to coerce the executive to deliver on their core responsibilities like providing basic services to the electorates (AIDS Law Project (2003). The National Democratic Institute for International Affairs and the Southern African Development Community Parliamentary Forum (2004) assert that the omission of Public Representatives and Legislatures in the HIV prevention agenda is a serious deficiency in the fight against HIV and AIDS. In light of this, this paper argues the innovative and legislative ways in which both the Public Representative and the Legislatures should play in HIV prevention.

Keywords: legislature, public representative, oversight, HIV and AIDS, constituency, service delivery

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Authors: Jiří Vágner, Dana Fialová

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The Covid-19 pandemic and its effects have triggered significant changes in travel behavior. On the contrary to a deep decline in international tourism, domestic tourism has recovered. It has not fully replaced the total volume of national tourism so far. However, from a regional point of view, and especially according to the type of destinations, regional targeting has changed significantly compared to the previous period. Urban destinations, which used to be the domain of foreign tourists, have been relatively orphaned, in contrast to destinations tied to natural attractions, which have seen seasonal increases. Even here, at a lower hierarchical geographic level, we can observe the differentiation resulting from the existing localization and infrastructure. The case study is focused on the three largest water reservoirs of the Vltava Cascade in Czechia– Lipno, Orlík, and Slapy. Based on a detailed field survey, in the periods before and during the pandemic, as well as available statistical data (Tourdata; Czech Statistical Office, Czech Cadaster and Ordnance Survey), different trends in the exploitation of these destinations with regard to existing or planned infrastructure are documented, analyzed and explained. This gives us the opportunity to discuss on concrete examples of generally known phenomena that are usually neglected in tourism: slum, brownfield, greenfield. Changes in travel behavior – especially the focus on spending leisure time individually in naturally attractive destinations – can affect the use of sites, which can be defined as a tourist or recreational slum, brownfield, but also as a tourist greenfield development. Sociocultural changes and perception of destinations by tourists and other actors represent, besides environmental changes, major trends in current tourism.

Keywords: Covid-19 pandemic, czechia, sociocultural and environmental impacts, tourist infrastructure, travel behavior, the Vltava Cascade water reservoirs

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Authors: Yu-Hsuan Chang, Jian-Hao Su, Chen-Yu Chen, Wei-Mon Yan

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In this work, the experimental measurement was applied to examine the membrane type and flow field design on the performance of a planar membrane humidifier. The performance indexes were used to evaluate the planar membrane humidifier. The performance indexes of the membrane humidifier include the dew point approach temperature (DPAT), water recovery ratio (WRR), water flux (J) and pressure loss (P). The experiments contain mainly three parts. In the first part, a single membrane humidifier was tested using different flow field under different dry-inlet temperatures. The measured results show that the dew point approach temperature decreases with increasing the depth of flow channel at the same width of flow channel. However, the WRR and J reduce with an increase in the dry air-inlet temperature. The pressure loss tests indicate that pressure loss decreases with increasing the hydraulic diameter of flow channel, resulting from an increase in Darcy friction. Owing to the comparison of humidifier performances and pressure losses, the flow channel of width W=1 and height H=1.5 was selected as the channel design of the multi-membrane humidifier in the second part of experiment. In the second part, the multi-membrane humidifier was used to evaluate the humidification performance under different relative humidity and flow rates. The measurement results indicate that the humidifier at both lower temperature and relative humidity of inlet dry air have higher DPAT but lower J and WRR. In addition, the counter flow approach has better mass and heat transfer performance than the parallel flow approach. Moreover, the effects of dry air temperature, relative humidity and humidification approach are not significant to the pressure loss in the planar membrane humidifier. For the third part, different membranes were tested in this work in order to find out which kind membrane is appropriate for humidifier.

Keywords: water management, planar membrane humidifier, heat and mass transfer, pressure loss, PEM fuel cell

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Authors: D. Deepak, N. Yagnesh Sharma

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Abrasive Water Jet (AWJ) machining is a relatively new nontraditional machine tool used in machining of fiber reinforced composite. The quality of machined surface depends on jet exit kinetic energy which depends on various operating and material parameters. In the present work the effect abrasive parameters such as its size, concentration and type on jet kinetic energy is investigated using computational fluid dynamics (CFD). In addition, the effect of these parameters on wall shear stress developed inside the nozzle is also investigated. It is found that for the same operating parameters, increase in the abrasive volume fraction (concentration) results in significant decrease in the wall shear stress as well as the jet exit kinetic energy. Increase in the abrasive particle size results in marginal decrease in the jet exit kinetic energy. Numerical simulation also indicates that garnet abrasives produce better jet exit kinetic energy than aluminium oxide and silicon carbide.

Keywords: abrasive water jet machining, jet kinetic energy, operating pressure, wall shear stress, Garnet abrasive

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Authors: G. T. Aigarinova

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This article considers the legal issues of food security as a major component of national security of the republic. The problem of food security is the top priority of the economic policy strategy of any state, the effectiveness of this solution influences social, political, and ethnic stability in society. Food security and nutrition is everyone’s business. Food security exists when all people, at all times, have physical, social and economic access to sufficient safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life. By analyzing the existing legislation in the area of food security, the author identifies weaknesses and gaps, suggesting ways to improve it.

Keywords: food security, national security, agriculture, public resources, economic security

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Authors: Eun-Taek Sin, Hyun-Ju Jang, Chang Geun Song, Yong-Sik Han

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Due to the climate change, the coastal urban area repeatedly suffers from the loss of property and life by flooding. There are three main causes of inland submergence. First, when heavy rain with high intensity occurs, the water quantity in inland cannot be drained into rivers by increase in impervious surface of the land development and defect of the pump, storm sewer. Second, river inundation occurs then water surface level surpasses the top of levee. Finally, Coastal inundation occurs due to rising sea water. However, previous studies ignored the complex mechanism of flooding, and showed discrepancy and inadequacy due to linear summation of each analysis result. In this study, inland flooding and river inundation were analyzed together by HDM-2D model. Petrov-Galerkin stabilizing method and flux-blocking algorithm were applied to simulate the inland flooding. In addition, sink/source terms with exponentially growth rate attribute were added to the shallow water equations to include the inland flooding analysis module. The applications of developed model gave satisfactory results, and provided accurate prediction in comprehensive flooding analysis. The applications of developed model gave satisfactory results, and provided accurate prediction in comprehensive flooding analysis. To consider the coastal surge, another module was developed by adding seawater to the existing Inland Flooding-River Inundation binding module for comprehensive flooding analysis. Based on the combined modules, the Coastal Inundation – Inland & River Flow Interface was simulated by inputting the flow rate and depth data in artificial flume. Accordingly, it was able to analyze the flood patterns of coastal cities over time. This study is expected to help identify the complex causes of flooding in coastal areas where complex flooding occurs, and assist in analyzing damage to coastal cities. Acknowledgements—This research was supported by a grant ‘Development of the Evaluation Technology for Complex Causes of Inundation Vulnerability and the Response Plans in Coastal Urban Areas for Adaptation to Climate Change’ [MPSS-NH-2015-77] from the Natural Hazard Mitigation Research Group, Ministry of Public Safety and Security of Korea.

Keywords: flooding analysis, river inundation, inland flooding, 2D hydrodynamic model

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Authors: Karina I. Hidas, Csaba Németh, Anna Visy, Judit Csonka, László Friedrich, Ildikó Cs. Nyulas-Zeke

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Egg yolk is a popular ingredient in the food industry due to its gelling, emulsifying, colouring, and coagulating properties. Because of the heat sensitivity of proteins, egg yolk can only be heat treated at low temperatures, so its shelf life, even with the addition of a preservative, is only a few weeks. Freezing can increase the shelf life of liquid egg yolk up to 1 year, but it undergoes gelling below -6 ° C, which is an irreversible phenomenon. The degree of gelation depends on the time and temperature of freezing and is influenced by the process of thawing. Therefore, in our experiment, we examined egg yolks thawed in different ways. In this study, unpasteurized, industrially broken, separated, and homogenized liquid egg yolk was used. Freshly produced samples were frozen in plastic containers at -18°C in a laboratory freezer. Frozen storage was performed for 90 days. Samples were analysed at day zero (unfrozen) and after frozen storage for 1, 7, 14, 30, 60 and 90 days. Samples were thawed in two ways (at 5°C for 24 hours and 30°C for 3 hours) before testing. Calorimetric properties were examined by differential scanning calorimetry, where heat flow curves were recorded. Denaturation enthalpy values were calculated by fitting a linear baseline, and denaturation temperature values were evaluated. Besides, dry matter content of samples was measured by the oven method with drying at 105°C to constant weight. For statistical analysis two-way ANOVA (α = 0.05) was employed, where thawing mode and freezing time were the fixed factors. Denaturation enthalpy values decreased from 1.1 to 0.47 at the end of the storage experiment, which represents a reduction of about 60%. The effect of freezing time was significant on these values, already the enthalpy of samples stored frozen for 1 day was significantly reduced. However, the mode of thawing did not significantly affect the denaturation enthalpy of the samples, and no interaction was seen between the two factors. The denaturation temperature and dry matter content did not change significantly either during the freezing period or during the defrosting mode. Results of our study show that slow freezing and frozen storage at -18°C greatly reduces the amount of protein that can be denatured in egg yolk, indicating that the proteins have been subjected to aggregation, denaturation or other protein conversions regardless of how they were thawed.

Keywords: denaturation enthalpy, differential scanning calorimetry, liquid egg yolk, slow freezing

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Authors: Nabia Siddiqui, Tahira Mohsin Ali, Tanveer Abbas, Abid Hasnain

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The present study proposed the use of different onion peel extracts in a South Asian snacks called ‘sew’. The polyphenols extracted from peels were initially analyzed for their antimicrobial potential and bioactive components following three different extraction systems. A relatively higher level of total phenolic content (TP), total flavonoid (TF) and antioxidant activity was observed for EWE (ethanol and water based) extracts followed by EAAE (ethanol and acetic acid) and WE (water extract) sample. Onion extracts showed ability to inhibit gram-positive as well as gram-negative bacteria. The incorporation of onion peel extracts in sew showed a marked increase in bioactive components. Besides bioactivity, sensory attributes, textural characteristics and storage stability of these snacks containing onion peel extract also significantly improved during the shelf study at ambient temperature for up to two months. Thus, these results justify the utilization of these plant polyphenols in fried snacks.

Keywords: onion peels extract, South Asian snacks, antioxidant capacity, bioactivity

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Authors: M. S. Yalfani, J. Kohzadi, P. Ghadimi, S. Sobhani, M. Ghadimi

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The use of oil and water-soluble corrosion inhibitors has been established in Iranian oil and gas production systems for a long time. Imidazoline and its derivatives are being extensively used which are known as conventional corrosion inhibitors. This type of product has shown significant performance and low side effects, so that could monopolize the market of inhibitors in this region. However, the price growth of imidazolines, as well as the development of new lower-cost components with similar or even higher performance than imidazoline, have influenced the exclusive market of imidazoline-based products. During the latest years, pyridine and its derivatives have challenged imidazoline due to their remarkable anticorrosive properties and lower prices as well. Recently, we presented a formulated water-soluble inhibitor based on pyridine - an alkyl pyridine quaternary salt (APQS) - which could successfully pass all lab tests and eventually succeeded in being applied in an offshore sweet oil pipeline. The product was able to achieve high corrosion protection (> 90 %) with the LPR technique at low dosages of 15-25 ppm under severe corrosion conditions. Moreover, the lab test results showed that the APQS molecule is able to form a strong and persistent bond with the metal surface. The product was later nominated to be evaluated through a field trial in an offshore sweet oil pipeline where PH2S < 0.05 psi and CO2 is 6.4 mol%. The three-month trial - extended to six months- resulted in remarkable internal protection obtained by continuous injection of 10 ppm inhibitor, which was as low as 1 mpy measured by both weight loss corrosion coupons and online ER probes. In addition, no side effects, such as tight emulsion and stable foaming, were observed. The residual of the corrosion inhibitor was measured at the end of the pipeline to ensure the full coverage of the inhibitor throughout the pipeline. Eventually, these promising results were able to convince the end user to consider pyridine-based inhibitors as a reliable alternative to imidazoline.

Keywords: corrosion inhibitor, pyridine, sweet oil, pipeline, offshore

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Authors: Ali Yaro Kankia

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Millennium Development Goals are eight goals set by the 189 United Nations member States with 2015 as its target year of achievement. Since its signing in September 2000, individual nations have been finding ways and means of actualizing them. This paper consider how a refocused basic Mathematics curriculum could serve as an appropriate tool in achieving these goals. This was done by considering the theme in the following sub-headings. Basic Mathematics curriculum before now, basic Mathematics curriculum and the millennium development Goals and challenges of a refocused basic Mathematics curriculum for the MDGs. The appropriate conclusion was reached.

Keywords: actualizing, curriculum, MDGs, refocused

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Authors: Mathewos Temesgen, Lemi Geleta

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Lake Koka is one of the Ethiopian Central Rift Valleys lakes, where the absorbance of domestic, agricultural, and industrial waste from the nearby industrial and agro-industrial activities is very common. The aim of this research was to assess the heavy metal bioaccumulation in edible parts of common carp (Cyprinus carpio) in Lake Koka and the health risks associated with the dietary intake of the fish. Three sampling sites were selected randomly for primary data collection. Physicochemical parameters (pH, Total Dissolved Solids, Dissolved Oxygen and Electrical Conductivity) were measured in-situ. Four heavy metals (Cd, Cr, Pb, and Zn) in water and bio-accumulation in the edible parts of the fish were analyzed with flame atomic absorption spectrometry. The mean values of TDS, EC, DO and pH of the lake water were 458.1 mg/L, 905.7 µ s/cm, 7.36 mg/L, and 7.9, respectively. The mean concentrations of Zn, Cr, and Cd in the edible part of fish were also 0.18 mg/kg, ND-0.24 mg/kg, and ND-0.03 mg/kg, respectively. Pb was, however, not identified. The amount of Cr in the examined fish muscle was above the level set by FAO, and the accumulation of the metals showed marked differences between sampling sites (p<0.05). The concentrations of Cd, Pb and were below the maximum permissible limit. The results also indicated that Cr has a high transfer factor value and Zn has the lowest. The carcinogenic hazard ratio values were below the threshold value (<1) for the edible parts of fish. The estimated weekly intake of heavy metals from fish muscles ranked as Cr>Zn>Cd, but the values were lower than the Reference Dose limit for metals. The carcinogenic risk values indicated a low health risk due to the intake of individual metals from fish. Furthermore, the hazard index of the edible part of fish was less than unity. Generally, the water quality is not a risk for the survival and reproduction of fish, and the heavy metal contents in the edible parts of fish exhibited low carcinogenic risk through the food chain.

Keywords: bio-accumulation, cyprinus carpio, hazard index, heavy metals, Lake Koka

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Authors: Cui Li, Xu Yuping

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Based on the question of, "Are short video creators who are digital workers controlled by platform rules?" this study discusses the specific ways of platform rules control and the impact on short video creators. Based on the theory of digital labor, this paper adopts the method of in-depth interview and participant observation and chooses 24 producers of short video content of Tiktok to conduct in-depth interview. At the same time, through entering the short video creation field, the author carries on the four-month field investigation, obtains the creation process related data, and analyzes how the short video creator, as the digital labor, is controlled by the platform rule, as well as the creator in this process of compromise and resistance, a more comprehensive presentation of the short video creators of the labor process. It is found that the short video creators are controlled by the platform rules, mainly in the control of traffic rules, and the creators create content, compromise and resist under the guidance of traffic. First, while the platform seems to offer a flexible and autonomous way for creators to monetize, the threshold for participating in the event is actually very high for creators, and the rules for monetizing the event are vague. Under the influence of the flow rule, the creator is faced unstable incomes and high costs. Therefore, creators have to follow the rules of traffic to guide their own creation, began to flow-oriented content production, mainly reflected in the need to keep up-to-date, the pursuit of traffic to ride on the hot spots, in order to flow regardless, set up people "Born for the show", by the label solidified content creation. Secondly, the irregular working hours lead to the extension and overwork of the working hours, which leads to the internal friction of the short video creators at the spiritual level, and finally leads to the Rat Race of video creation. Thirdly, the video creator has completed the internalization and compromise of the platform rules in practice, which promotes the creator to continue to create independently, and forms the intrinsic motive force of the creator. Finally, the rule-controlled short video creators resist and fight in flexible ways, make use of the mechanism and rules of the platform to carry on the second creation, carry on the routine production, purchase the false flow, transfer the creation position to maintain own creation autonomy.

Keywords: short videos, tiktok, production, digital labors

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