Search results for: powder holding capacities
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1765

Search results for: powder holding capacities

205 Electrospun Fibre Networks Loaded with Hydroxyapatite and Barium Titanate as Smart Scaffolds for Tissue Regeneration

Authors: C. Busuioc, I. Stancu, A. Nicoara, A. Zamfirescu, A. Evanghelidis

Abstract:

The field of tissue engineering has expanded its potential due to the use of composite biomaterials belonging to increasingly complex systems, leading to bone substitutes with properties that are continuously improving to meet the patient's specific needs. Furthermore, the development of biomaterials based on ceramic and polymeric phases is an unlimited resource for future scientific research, with the final aim of restoring the original tissue functionality. Thus, in the first stage, composite scaffolds based on polycaprolactone (PCL) or polylactic acid (PLA) and inorganic powders were prepared by employing the electrospinning technique. The targeted powders were: commercial and laboratory synthesized hydroxyapatite (HAp), as well as barium titanate (BT). By controlling the concentration of the powder within the precursor solution, together with the processing parameters, different types of three-dimensional architectures were achieved. In the second stage, both the mineral powders and hybrid composites were investigated in terms of composition, crystalline structure, and microstructure so that to demonstrate their suitability for tissue engineering applications. Regarding the scaffolds, these were proven to be homogeneous on large areas and loaded with mineral particles in different proportions. The biological assays demonstrated that the addition of inorganic powders leads to modified responses in the presence of simulated body fluid (SBF) or cell cultures. Through SBF immersion, the biodegradability coupled with bioactivity were highlighted, with fiber fragmentation and surface degradation, as well as apatite layer formation within the testing period. Moreover, the final composites represent supports accepted by the cells, favoring implant integration. Concluding, the purposed fibrous materials based on bioresorbable polymers and mineral powders, produced by the electrospinning technique, represent candidates with considerable potential in the field of tissue engineering. Future improvements can be attained by optimizing the synthesis process or by simultaneous incorporation of multiple inorganic phases with well-defined biological action in order to fabricate multifunctional composites.

Keywords: barium titanate, electrospinning, fibre networks, hydroxyapatite, smart scaffolds

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204 The Relationship between Anthropometric Obesity Indices and Insulin in Children with Metabolic Syndrome

Authors: Mustafa M. Donma, Orkide Donma

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The number of indices developed for the evaluation of obesity both in adults and pediatric population is ever increasing. These indices are also used in cases with metabolic syndrome (MetS), mostly the ultimate form of morbid obesity. Aside from anthropometric measurements, formulas constituted using these parameters also find clinical use. These formulas can be listed as two groups; being weight-dependent and –independent. Some are extremely sophisticated equations and their clinical utility is questionable in routine clinical practice. The aim of this study is to compare presently available obesity indices and find the most practical one. Their associations with MetS components were also investigated to determine their capacities in differential diagnosis of morbid obesity with and without MetS. Children with normal body mass index (N-BMI) and morbid obesity were recruited for this study. Three groups were constituted. Age- and sex- dependent BMI percentiles for morbid obese (MO) children were above 99 according to World Health Organization tables. Of them, those with MetS findings were evaluated as MetS group. Children, whose values were between 85 and 15 were included in N-BMI group. The study protocol was approved by the Ethics Committee of the Institution. Parents filled out informed consent forms to participate in the study. Anthropometric measurements and blood pressure values were recorded. Body mass index, hip index (HI), conicity index (CI), triponderal mass index (TPMI), body adiposity index (BAI), body shape index (ABSI), body roundness index (BRI), abdominal volume index (AVI), waist-to-hip ratio (WHR) and waist circumference+hip circumference/2 ((WC+HC)/2) were the formulas examined within the scope of this study. Routine biochemical tests including fasting blood glucose (FBG), insulin (INS), triglycerides (TRG), high density lipoprotein-cholesterol (HDL-C) were performed. Statistical package program SPSS was used for the evaluation of study data. p<0.05 was accepted as the statistical significance degree. Hip index did not differ among the groups. A statistically significant difference was noted between N-BMI and MetS groups in terms of ABSI. All the other indices were capable of making discrimination between N-BMI-MO, N-BMI- MetS and MO-MetS groups. No correlation was found between FBG and any obesity indices in any groups. The same was true for INS in N-BMI group. Insulin was correlated with BAI, TPMI, CI, BRI, AVI and (WC+HC)/2 in MO group without MetS findings. In MetS group, the only index, which was correlated with INS was (WC+HC)/2. These findings have pointed out that complicated formulas may not be required for the evaluation of the alterations among N-BMI and various obesity groups including MetS. The simple easily computable weight-independent index, (WC+HC)/2, was unique, because it was the only index, which exhibits a valuable association with INS in MetS group. It did not exhibit any correlation with other obesity indices showing associations with INS in MO group. It was concluded that (WC+HC)/2 was pretty valuable practicable index for the discrimination of MO children with and without MetS findings.

Keywords: children, insulin, metabolic syndrome, obesity indices

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203 Colonizing the Colonizers: Layers of Subjectification in the Russian Caucasus

Authors: Aaron Derner

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Unlike the histories of France, the UK, or even Spain, the Russian colonial past often dissolves before the seemingly more salient Cold War figurations or Soviet dissolution. The obvious explanation behind Caucasian states’ roles—that of Russian-propped governments obeying the whims of their patron—is but the latest instance of such oversight. Where the results of colonial social and cultural interactions are indelibly stamped across France, Algeria, and every other former (and current) French holding, so to are the Muscovite and Russian colonial ambitions embedded within the modern politics and cultures of both Russia and the Caucasus. Russian colonial artefacts are enhanced and perhaps granted an additional social explanatory edge over those of the ‘typical’ colonizers, by the cyclical adoration for and noisy rejection of European cultural markers over the centuries, along with the somewhat unusual composition of the Cossacks: Russia’s main agents of colonialization within the Caucasian frontier. The story of Russia and Chechnya, of all the Caucasus, is of the manufacture of social and individual identity through “modes of subjectification” inherent within the region’s colonial history and driven by the triangular interactions between three main groups: the Cossacks, the Caucasian Mountain Tribes, and the Russian Metropol. Together, interactions between these social groups worked to shape and transform the lifestyles and institutional pathologies that constitute the Russian and Chechen states and the politics between them. At the core of this (Western) state-building is the simultaneous and seemingly contradictory desire to be more Western and emulate Western cultural and political practices while also desperately grasping for a uniquely Russian identity. This sits somewhat ironically against the backdrop that Russia hosted a frontier-based settler society and had established that distinctly European feature of settler colonialism early in its history—arguably establishing a claim to being the most “colonial” of the colonial powers. There is no doubt that these forces worked to shape contemporary Russian political and social identity—apparent in the mythic popularity of the Cossack in Russian literature, politics, and academic discourse. What needs to be expanded from the current narrative, however, is that beyond the Cossack identity’s attractiveness on the grounds of its tones of freedom and resistance to unjust authority, the identity is rooted in the imperial ambitions and colonial experiences of the Russian state, and is, therefore, a direct marker of domination and subjectification. Adding an unusual dimension to this not-uncommon cultural progression, the Russian state needed to colonize both the Caucases and the Russian Cossacks, appropriating them in much the same way they appropriated the Circassian mountain tribes. The focus of this paper is not to tell yet another story of how one culture entered an area to overpower another but how a ‘powerful,’ ‘modern,’ ‘Western(ish)’ culture was profoundly and continually changed through its contact with a group of tribal ‘savages’ and ‘braves.’

Keywords: Russia, chechnya, subjectification, caucasus, cossacks, Ukraine

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202 Feasibility Study of Particle Image Velocimetry in the Muzzle Flow Fields during the Intermediate Ballistic Phase

Authors: Moumen Abdelhafidh, Stribu Bogdan, Laboureur Delphine, Gallant Johan, Hendrick Patrick

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This study is part of an ongoing effort to improve the understanding of phenomena occurring during the intermediate ballistic phase, such as muzzle flows. A thorough comprehension of muzzle flow fields is essential for optimizing muzzle device and projectile design. This flow characterization has heretofore been almost entirely limited to local and intrusive measurement techniques such as pressure measurements using pencil probes. Consequently, the body of quantitative experimental data is limited, so is the number of numerical codes validated in this field. The objective of the work presented here is to demonstrate the applicability of the Particle Image Velocimetry (PIV) technique in the challenging environment of the propellant flow of a .300 blackout weapon to provide accurate velocity measurements. The key points of a successful PIV measurement are the selection of the particle tracer, their seeding technique, and their tracking characteristics. We have experimentally investigated the aforementioned points by evaluating the resistance, gas dispersion, laser light reflection as well as the response to a step change across the Mach disk for five different solid tracers using two seeding methods. To this end, an experimental setup has been performed and consisted of a PIV system, the combustion chamber pressure measurement, classical high-speed schlieren visualization, and an aerosol spectrometer. The latter is used to determine the particle size distribution in the muzzle flow. The experimental results demonstrated the ability of PIV to accurately resolve the salient features of the propellant flow, such as the under the expanded jet and vortex rings, as well as the instantaneous velocity field with maximum centreline velocities of more than 1000 m/s. Besides, naturally present unburned particles in the gas and solid ZrO₂ particles with a nominal size of 100 nm, when coated on the propellant powder, are suitable as tracers. However, the TiO₂ particles intended to act as a tracer, surprisingly not only melted but also functioned as a combustion accelerator and decreased the number of particles in the propellant gas.

Keywords: intermediate ballistic, muzzle flow fields, particle image velocimetry, propellant gas, particle size distribution, under expanded jet, solid particle tracers

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201 Advancing Hydrogen Production Through Additive Manufacturing: Optimising Structures of High Performance Electrodes

Authors: Fama Jallow, Melody Neaves, Professor Mcgregor

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The quest for sustainable energy sources has driven significant interest in hydrogen production as a clean and efficient fuel. Alkaline water electrolysis (AWE) has emerged as a prominent method for generating hydrogen, necessitating the development of advanced electrode designs with improved performance characteristics. Additive manufacturing (AM) by laser powder bed fusion (LPBF) method presents an opportunity to tailor electrode microstructures and properties, enhancing their performance. This research proposes investigating the AM of electrodes with different lattice structures to optimize hydrogen production. The primary objective is to employ advanced modeling techniques to identify and select two optimal lattice structures for electrode fabrication. LPBF will be used to fabricate electrodes with precise control over lattice geometry, pore size, and distribution. The performance evaluation will encompass energy consumption and porosity analysis. AWE will assess energy efficiency, aiming to identify lattice structures with enhanced hydrogen production rates and reduced power requirements. Computed tomography (CT) scanning will analyze porosity to determine material integrity and mass transport characteristics. The research aims to bridge the gap between AM and hydrogen production by investigating lattice structures potential in electrode design. By systematically exploring lattice structures and their impact on performance, this study aims to provide valuable insights into the design and fabrication of highly efficient and cost-effective electrodes for AWE. The outcomes hold promise for advancing hydrogen production through AM. The research will have a significant impact on the development of sustainable energy sources. The findings from this study will help to improve the efficiency of AWE, making it a more viable option for hydrogen production. This could lead to a reduction in our reliance on fossil fuels, which would have a positive impact on the environment. The research is also likely to have a commercial impact. The findings could be used to develop new electrode designs that are more efficient and cost-effective. This could lead to the development of new hydrogen production technologies, which could have a significant impact on the energy market.

Keywords: hydrogen production, electrode, lattice structure, Africa

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200 Time Travel Testing: A Mechanism for Improving Renewal Experience

Authors: Aritra Majumdar

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While organizations strive to expand their new customer base, retaining existing relationships is a key aspect of improving overall profitability and also showcasing how successful an organization is in holding on to its customers. It is an experimentally proven fact that the lion’s share of profit always comes from existing customers. Hence seamless management of renewal journeys across different channels goes a long way in improving trust in the brand. From a quality assurance standpoint, time travel testing provides an approach to both business and technology teams to enhance the customer experience when they look to extend their partnership with the organization for a defined phase of time. This whitepaper will focus on key pillars of time travel testing: time travel planning, time travel data preparation, and enterprise automation. Along with that, it will call out some of the best practices and common accelerator implementation ideas which are generic across verticals like healthcare, insurance, etc. In this abstract document, a high-level snapshot of these pillars will be provided. Time Travel Planning: The first step of setting up a time travel testing roadmap is appropriate planning. Planning will include identifying the impacted systems that need to be time traveled backward or forward depending on the business requirement, aligning time travel with other releases, frequency of time travel testing, preparedness for handling renewal issues in production after time travel testing is done and most importantly planning for test automation testing during time travel testing. Time Travel Data Preparation: One of the most complex areas in time travel testing is test data coverage. Aligning test data to cover required customer segments and narrowing it down to multiple offer sequencing based on defined parameters are keys for successful time travel testing. Another aspect is the availability of sufficient data for similar combinations to support activities like defect retesting, regression testing, post-production testing (if required), etc. This section will talk about the necessary steps for suitable data coverage and sufficient data availability from a time travel testing perspective. Enterprise Automation: Time travel testing is never restricted to a single application. The workflow needs to be validated in the downstream applications to ensure consistency across the board. Along with that, the correctness of offers across different digital channels needs to be checked in order to ensure a smooth customer experience. This section will talk about the focus areas of enterprise automation and how automation testing can be leveraged to improve the overall quality without compromising on the project schedule. Along with the above-mentioned items, the white paper will elaborate on the best practices that need to be followed during time travel testing and some ideas pertaining to accelerator implementation. To sum it up, this paper will be written based on the real-time experience author had on time travel testing. While actual customer names and program-related details will not be disclosed, the paper will highlight the key learnings which will help other teams to implement time travel testing successfully.

Keywords: time travel planning, time travel data preparation, enterprise automation, best practices, accelerator implementation ideas

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199 Shaped Crystal Growth of Fe-Ga and Fe-Al Alloy Plates by the Micro Pulling down Method

Authors: Kei Kamada, Rikito Murakami, Masahiko Ito, Mototaka Arakawa, Yasuhiro Shoji, Toshiyuki Ueno, Masao Yoshino, Akihiro Yamaji, Shunsuke Kurosawa, Yuui Yokota, Yuji Ohashi, Akira Yoshikawa

Abstract:

Techniques of energy harvesting y have been widely developed in recent years, due to high demand on the power supply for ‘Internet of things’ devices such as wireless sensor nodes. In these applications, conversion technique of mechanical vibration energy into electrical energy using magnetostrictive materials n have been brought to attention. Among the magnetostrictive materials, Fe-Ga and Fe-Al alloys are attractive materials due to the figure of merits such price, mechanical strength, high magnetostrictive constant. Up to now, bulk crystals of these alloys are produced by the Bridgman–Stockbarger method or the Czochralski method. Using these method big bulk crystal up to 2~3 inch diameter can be grown. However, non-uniformity of chemical composition along to the crystal growth direction cannot be avoid, which results in non-uniformity of magnetostriction constant and reduction of the production yield. The micro-pulling down (μ-PD) method has been developed as a shaped crystal growth technique. Our group have reported shaped crystal growth of oxide, fluoride single crystals with different shape such rod, plate tube, thin fiber, etc. Advantages of this method is low segregation due to high growth rate and small diffusion of melt at the solid-liquid interface, and small kerf loss due to near net shape crystal. In this presentation, we report the shaped long plate crystal growth of Fe-Ga and Fe-Al alloys using the μ-PD method. Alloy crystals were grown by the μ-PD method using calcium oxide crucible and induction heating system under the nitrogen atmosphere. The bottom hole of crucibles was 5 x 1mm² size. A <100> oriented iron-based alloy was used as a seed crystal. 5 x 1 x 320 mm³ alloy crystal plates were successfully grown. The results of crystal growth, chemical composition analysis, magnetostrictive properties and a prototype vibration energy harvester are reported. Furthermore, continuous crystal growth using powder supply system will be reported to minimize the chemical composition non-uniformity along the growth direction.

Keywords: crystal growth, micro-pulling-down method, Fe-Ga, Fe-Al

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198 Development of the Family Capacity of Management of Patients with Autism Spectrum Disorder Diagnosis

Authors: Marcio Emilio Dos Santos, Kelly C. F. Dos Santos

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Caregivers of patients diagnosed with ASD are subjected to high stress situations due to the complexity and multiple levels of daily activities that require the organization of events, behaviors and socioemotional situations, such as immediate decision making and in public spaces. The cognitive and emotional requirement needed to fulfill this caregiving role exceeds the regular cultural process that adults receive in their process of preparation for conjugal and parental life. Therefore, in many cases, caregivers present a high level of overload, poor capacity to organize and mediate the development process of the child or patient about their care. Aims: Improvement in the cognitive and emotional capacities related to the caregiver function, allowing the reduction of the overload, the feeling of incompetence and the characteristic level of stress, developing a more organized conduct and decision making more oriented towards the objectives and procedural gains necessary for the integral development of the patient with diagnosis of ASD. Method: The study was performed with 20 relatives, randomly selected from a total of 140 patients attended. The family members were submitted to the Wechsler Adult Intelligence Scale III intelligence test and the Family assessment Management Measure (FaMM) questionnaire as a previous evaluation. Therapeutic activity in a small group of family members or caregivers, with weekly frequency, with a minimum workload of two hours, using the Feuerstein Instrumental Enrichment Cognitive Development Program - Feuerstein Instrumental Enrichment for ten months. Reapplication of the previous tests to verify the gains obtained. Results and Discussion: There is a change in the level of caregiver overload, improvement in the results of the Family assessment Management Measure and highlight to the increase of performance in the cognitive aspects related to problem solving, planned behavior and management of behavioral crises. These results lead to the discussion of the need to invest in the integrated care of patients and their caregivers, mainly by enabling cognitively to deal with the complexity of Autism. This goes beyond the simple therapeutic orientation about adjustments in family and school routines. The study showed that when the caregiver improves his/her capacity of management, the results of the treatment are potentiated and there is a reduction of the level of the caregiver's overload. Importantly, the study was performed for only ten months and the number of family members attended in the study (n = 20) needs to be expanded to have statistical strength.

Keywords: caregiver overload, cognitive development program ASD caregivers, feuerstein instrumental enrichment, family assessment management measure

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197 Bedouin Dispersion in Israel: Between Sustainable Development and Social Non-Recognition

Authors: Tamir Michal

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The subject of Bedouin dispersion has accompanied the State of Israel from the day of its establishment. From a legal point of view, this subject has offered a launchpad for creative judicial decisions. Thus, for example, the first court decision in Israel to recognize affirmative action (Avitan), dealt with a petition submitted by a Jew appealing the refusal of the State to recognize the Petitioner’s entitlement to the long-term lease of a plot designated for Bedouins. The Supreme Court dismissed the petition, holding that there existed a public interest in assisting Bedouin to establish permanent urban settlements, an interest which justifies giving them preference by selling them plots at subsidized prices. In another case (The Forum for Coexistence in the Negev) the Supreme Court extended equitable relief for the purpose of constructing a bridge, even though the construction infringed the Law, in order to allow the children of dispersed Bedouin to reach school. Against this background, the recent verdict, delivered during the Protective Edge military campaign, which dismissed a petition aimed at forcing the State to spread out Protective Structures in Bedouin villages in the Negev against the risk of being hit from missiles launched from Gaza (Abu Afash) is disappointing. Even if, in arguendo, no selective discrimination was involved in the State’s decision not to provide such protection, the decision, and its affirmation by the Court, is problematic when examined through the prism of the Theory of Recognition. The article analyses the issue by tools of theory of Recognition, according to which people develop their identities through mutual relations of recognition in different fields. In the social context, the path to recognition is cognitive respect, which is provided by means of legal rights. By seeing other participants in Society as bearers of rights and obligations, the individual develops an understanding of his legal condition as reflected in the attitude to others. Consequently, even if the Court’s decision may be justified on strict legal grounds, the fact that Jewish settlements were protected during the military operation, whereas Bedouin villages were not, is a setback in the struggle to make the Bedouin citizens with equal rights in Israeli society. As the Court held, ‘Beyond their protective function, the Migunit [Protective Structures] may make a moral and psychological contribution that should not be undervalued’. This contribution is one that the Bedouin did not receive in the Abu Afash verdict. The basic thesis is that the Court’s verdict analyzed above clearly demonstrates that the reliance on classical liberal instruments (e.g., equality) cannot secure full appreciation of all aspects of Bedouin life, and hence it can in fact prejudice them. Therefore, elements of the recognition theory should be added, in order to find the channel for cognitive dignity, thereby advancing the Bedouins’ ability to perceive themselves as equal human beings in the Israeli society.

Keywords: bedouin dispersion, cognitive respect, recognition theory, sustainable development

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196 Decentralized Forest Policy for Natural Sal (Shorea robusta) Forests Management in the Terai Region of Nepal

Authors: Medani Prasad Rijal

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The study outlines the impacts of decentralized forest policy on natural Sal (shorea robusta) forests in the Terai region of Nepal. The government has implemented community forestry program to manage the forest resources and improve the livelihood of local people collectively. The forest management authorities such as conserve, manage, develop and use of forest resources were shifted to the local communities, however, the ownership right of the forestland retained by the government. Local communities took the decision on harvesting, distribution, and sell of forest products by fixing the prices independently. The local communities were putting the low value of forest products and distributed among the user households on the name of collective decision. The decision of low valuation is devaluating the worth of forest products. Therefore, the study hypothesized that decision-making capacities are equally prominent next to the decentralized policy and program formulation. To accomplish the study, individual to group level discussions and questionnaire survey methods were applied with executive committee members and user households. The study revealed that the local intuition called Community Forest User Group (CFUG) committee normally took the decisions on consensus basis. Considering to the access and affording capacity of user households having poor economic backgrounds, low pricing mechanism of forest products has been practiced, even though the Sal timber is far expensive in the local market. The local communities thought that low pricing mechanism is accessible to all user households from poor to better off households. However, the analysis of forest products distribution opposed the assumption as most of the Sal timber, which is the most valuable forest product of community forest only purchased by the limited households of better economic conditions. Since the Terai region is heterogeneous by socio-economic conditions, better off households always have higher affording capacity and possibility of taking higher timber benefits because of low price mechanism. On the other hand, the minimum price rate of forest products has poor contribution in community fund collection. Consequently, it has poor support to carry out poverty alleviation activities to poor people. The local communities have been fixed Sal timber price rate around three times cheaper than normal market price, which is a strong evidence of forest product devaluation itself. Finally, the study concluded that the capacity building of local executives as the decision-makers of natural Sal forests is equally indispensable next to the policy and program formulation for effective decentralized forest management. Unilateral decentralized forest policy may devaluate the forest products rather than devolve of power to the local communities and empower to them.

Keywords: community forestry program, decentralized forest policy, Nepal, Sal forests, Terai

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195 Inclusion Complexes of Some Imidazoline Drugs with Cucurbit[N]Uril (N=7,8): Preparation, Characterization and Theoretical Calculations

Authors: Fakhreldin O. Suliman, Alia H. Al-Battashi

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This work explored the interaction of three different imidazoline drugs, naphazoline nitrate (NPH), oxymetazoline hydrochloride (OXY) and xylometazoline hydrochloride (XYL) with two different synthesized cucurbit[n]urils CB[n], cucurbit[7]uril (CB[7]) and cucuribit[8]uril (CB[8]). Three binary inclusion complexes have been investigated in solution and in the solid state. The solid complexes were obtained by lyophilization, whereas the physical mixtures of guests and hosts at a stoichiometric ratio of 1:1 were obtained for each drug. 1HNMR, electrospray ionization mass spectrometry (ESI-MS), and matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry was used to study the complexes prepared in aqueous media. The lyophilized solid complexes were characterized by Fourier transform-infrared spectroscopy (FT-IR), powder X-ray diffractometry (PXRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). MS, FT-IR and PXRD experimental results established in this work reveal that NPH, OXY and XYL molecules form stable inclusion complexes with the two hosts. The TGA and DSC confirmed the enhancement of the thermal stability of each drug and the production of a thermally stable solid complex. The 1HNMR has shown that the protons of the guests faced shifting in ppm and broadening of their peaks upon the formation of inclusion complexes with the selected CB[n]. The aromatic protons of the guest exhibited the highest changes in the chemical shifts and shape of the NMR peaks, suggesting their inclusion into the cavity of the CB[n]. The diffusion coefficients (D), developed from the diffusion-controlled NMR Spectroscopy (DOSY) measurements, for the complexation of the selected imidazoline drugs with CB[7] and CB[8], were decreased in the presence of hosts compared to the free guests indicating the formation of the guest-host adduct. Furthermore, we conducted molecular dynamic simulations and quantum mechanics calculations on these complexes. The results of the theoretical study corroborate the experimental findings and have also shed light on the mechanism of inclusion of the guests into the two hosts. This study generates initial data for potential drug delivery or drug formulation systems for these three selected imidazoline drug compounds based on their inclusion into the CB[n] cavities.

Keywords: cucurbit[n]urils, imidazoline, inclusion complexes, molecular dynamics, DFT calculations, mass spectrometry

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194 Assessment of Selected Marine Organisms from Malaysian Coastal Areas for Inhibitory Activity against the Chikungunya Virus

Authors: Yik Sin Chan, Nam Weng Sit, Fook Yee Chye, van Ofwegen Leen, de Voogd Nicole, Kong Soo Khoo

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Chikungunya fever is an arboviral disease transmitted by the Aedes mosquitoes. It has resulted in epidemics of the disease in tropical countries in the Indian Ocean and South East Asian regions. The recent spread of this disease to the temperate countries such as France and Italy, coupled with the absence of vaccines and effective antiviral drugs make chikungunya fever a worldwide health threat. This study aims to investigate the anti-chikungunya virus activity of selected marine organism samples collected from Malaysian coastal areas, including seaweeds (Caulerpa racemosa, Caulerpa sertularioides and Kappaphycus alvarezii), a soft coral (Lobophytum microlobulatum) and a sponge (Spheciospongia vagabunda). Following lyophilization (oven drying at 40C for K. alvarezii) and grinding to powder form, each sample was subjected to sequential solvent extraction using hexane, chloroform, ethyl acetate, ethanol, methanol and distilled water in order to extract bioactive compounds. The antiviral activity was evaluated using monkey kidney epithelial (Vero) cells infected with the virus (multiplicity of infection=1). The cell viability was determined by Neutral Red uptake assay. 70% of the 30 extracts showed weak inhibitory activity with cell viability ≤30%. Seven of the extracts exhibited moderate inhibitory activity (cell viability: 31%-69%). These were the chloroform, ethyl acetate, ethanol and methanol extracts of C. racemosa; chloroform and ethyl acetate extracts of L. microlobulatum; and the chloroform extract of C. sertularioides. Only the hexane and ethanol extracts of L. microlobulatum showed strong inhibitory activity against the virus, resulting in cell viabilities (mean±SD; n=3) of 73.3±2.6% and 79.2±0.9%, respectively. The corresponding mean 50% effective concentrations (EC50) for the extracts were 14.2±0.2 and 115.3±1.2 µg/mL, respectively. The ethanol extract of the soft coral L. microlobulatum appears to hold the most promise for further characterization of active principles as it possessed greater selectivity index (SI>5.6) compared to the hexane extract (SI=2.1).

Keywords: antiviral, seaweed, sponge, soft coral, vero cell

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193 Synthesis of Iron Oxide Nanoparticles Using Different Stabilizers and Study of Their Size and Properties

Authors: Mohammad Hassan Ramezan zadeh 1 , Majid Seifi 2 , Hoda Hekmat ara 2 1Biomedical Engineering Department, Near East University, Nicosia, Cyprus 2Physics Department, Guilan University , P.O. Box 41335-1914, Rasht, Iran.

Abstract:

Magnetic nano particles of ferric chloride were synthesised using a co-precipitation technique. For the optimal results, ferric chloride at room temperature was added to different surfactant with different ratio of metal ions/surfactant. The samples were characterised using transmission electron microscopy, X-ray diffraction and Fourier transform infrared spectrum to show the presence of nanoparticles, structure and morphology. Magnetic measurements were also carried out on samples using a Vibrating Sample Magnetometer. To show the effect of surfactant on size distribution and crystalline structure of produced nanoparticles, surfactants with various charge such as anionic cetyl trimethyl ammonium bromide (CTAB), cationic sodium dodecyl sulphate (SDS) and neutral TritonX-100 was employed. By changing the surfactant and ratio of metal ions/surfactant the size and crystalline structure of these nanoparticles were controlled. We also show that using anionic stabilizer leads to smallest size and narrowest size distribution and the most crystalline (polycrystalline) structure. In developing our production technique, many parameters were varied. Efforts at reproducing good yields indicated which of the experimental parameters were the most critical and how carefully they had to be controlled. The conditions reported here were the best that we encountered but the range of possible parameter choice is so large that these probably only represent a local optimum. The samples for our chemical process were prepared by adding 0.675 gr ferric chloride (FeCl3, 6H2O) to three different surfactant in water solution. The solution was sonicated for about 30 min until a transparent solution was achieved. Then 0.5 gr sodium hydroxide (NaOH) as a reduction agent was poured to the reaction drop by drop which resulted to participate reddish brown Fe2O3 nanoparticles. After washing with ethanol the obtained powder was calcinated in 600°C for 2h. Here, the sample 1 contained CTAB as a surfactant with ratio of metal ions/surfactant 1/2, sample 2 with CTAB and ratio 1/1, sample 3 with SDS and ratio 1/2, sample 4 SDS 1/1, sample 5 is triton-X-100 with 1/2 and sample 6 triton-X-100 with 1/1.

Keywords: iron oxide nanoparticles, stabilizer, co-precipitation, surfactant

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192 The Microstructure and Corrosion Behavior of High Entropy Metallic Layers Electrodeposited by Low and High-Temperature Methods

Authors: Zbigniew Szklarz, Aldona Garbacz-Klempka, Magdalena Bisztyga-Szklarz

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Typical metallic alloys bases on one major alloying component, where the addition of other elements is intended to improve or modify certain properties, most of all the mechanical properties. However, in 1995 a new concept of metallic alloys was described and defined. High Entropy Alloys (HEA) contains at least five alloying elements in an amount from 5 to 20 at.%. A common feature this type of alloys is an absence of intermetallic phases, high homogeneity of the microstructure and unique chemical composition, what leads to obtaining materials with very high strength indicators, stable structures (also at high temperatures) and excellent corrosion resistance. Hence, HEA can be successfully used as a substitutes for typical metallic alloys in various applications where a sufficiently high properties are desirable. For fabricating HEA, a few ways are applied: 1/ from liquid phase i.e. casting (usually arc melting); 2/ from solid phase i.e. powder metallurgy (sintering methods preceded by mechanical synthesis) and 3/ from gas phase e.g. sputtering or 4/ other deposition methods like electrodeposition from liquids. Application of different production methods creates different microstructures of HEA, which can entail differences in their properties. The last two methods also allows to obtain coatings with HEA structures, hereinafter referred to as High Entropy Films (HEF). With reference to above, the crucial aim of this work was the optimization of the manufacturing process of the multi-component metallic layers (HEF) by the low- and high temperature electrochemical deposition ( ED). The low-temperature deposition process was crried out at ambient or elevated temperature (up to 100 ᵒC) in organic electrolyte. The high-temperature electrodeposition (several hundred Celcius degrees), in turn, allowed to form the HEF layer by electrochemical reduction of metals from molten salts. The basic chemical composition of the coatings was CoCrFeMnNi (known as Cantor’s alloy). However, it was modified by other, selected elements like Al or Cu. The optimization of the parameters that allow to obtain as far as it possible homogeneous and equimolar composition of HEF is the main result of presented studies. In order to analyse and compare the microstructure, SEM/EBSD, TEM and XRD techniques were employed. Morover, the determination of corrosion resistance of the CoCrFeMnNi(Cu or Al) layers in selected electrolytes (i.e. organic and non-organic liquids) was no less important than the above mentioned objectives.

Keywords: high entropy alloys, electrodeposition, corrosion behavior, microstructure

Procedia PDF Downloads 57
191 Antibacterial Effects of Some Medicinal and Aromatic Plant Extracts on Pathogenic Bacteria Isolated from Pear Orchards

Authors: Kubilay Kurtulus Bastas

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Bacterial diseases are very destructive and cause economic losses on pears. Promising plant extracts for the management of plant diseases are environmentally safe, long-lasting and extracts of certain plants contain alkaloids, tannins, quinones, coumarins, phenolic compounds, and phytoalexins. In this study, bacteria were isolated from different parts of pear exhibiting characteristic symptoms of bacterial diseases from the Central Anatolia, Turkey. Pathogenic bacteria were identified by morphological, physiological, biochemical and molecular methods as fire blight (Erwinia amylovora (39%)), bacterial blossom blast and blister bark (Pseudomonas syringae pv. syringae (22%)), crown gall (Rhizobium radiobacter (1%)) from different pear cultivars, and determined virulence levels of the pathogens with pathogenicity tests. The air-dried 25 plant material was ground into fine powder and extraction was performed at room temperature by maceration with 80% (v/v) methanol/distilled water. The minimum inhibitory concentration (MIC) values were determined by using modified disc diffusion method at five different concentrations and streptomycin sulphate was used as control chemical. Bacterial suspensions were prepared as 108 CFU ml⁻¹ densities and 100 µl bacterial suspensions were spread to TSA medium. Antimicrobial activity was evaluated by measuring the inhibition zones in reference to the test organisms. Among the tested plants, Origanum vulgare, Hedera helix, Satureja hortensis, Rhus coriaria, Eucalyptus globulus, Rosmarinus officinalis, Ocimum basilicum, Salvia officinalis, Cuminum cyminum and Thymus vulgaris showed a good antibacterial activity and they inhibited the growth of the pathogens with inhibition zone diameter ranging from 7 to 27 mm at 20% (w/v) in absolute methanol in vitro conditions. In vivo, the highest efficacy was determined as 27% on reducing tumor formation of R. radiobacter, and 48% and 41% on reducing shoot blight of E. amylovora and P. s. pv. syringae on pear seedlings, respectively. Obtaining data indicated that some plant extracts may be used against the bacterial diseases on pome fruits within sustainable and organic management programs.

Keywords: bacteria, eco-friendly management, organic, pear, plant extract

Procedia PDF Downloads 303
190 The Role of Interest Groups in Foreign Policy: Assessing the Influence of the 'Pro-Jakarta Lobby' in Australia and Indonesia's Bilateral Relations

Authors: Bec Strating

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This paper examines the ways that domestic politics and pressure–generated through lobbying, public diplomacy campaigns and other tools of soft power-contributes to the formation of short-term and long-term national interests, priorities and strategies of states in their international relations. It primarily addresses the conceptual problems regarding the kinds of influence that lobby groups wield in foreign policy and how this influence might be assessed. Scholarly attention has been paid to influential foreign policy lobbies and interest groups, particularly in the areas of US foreign policy. Less attention has been paid to how lobby groups might influence the foreign policy of a middle power such as Australia. This paper examines some of the methodological complexities in developing and conducting a research project that can measure the nature and influence of lobbies on foreign affairs priorities and activities. This paper will use Australian foreign policy in the context of its historical bilateral relationship with Indonesia as a case study for considering the broader issues of domestic influences on foreign policy. Specifically, this paper will use the so-called ‘pro-Jakarta lobby’ as an example of an interest group. The term ‘pro-Jakarta lobby’ is used in media commentary and scholarship to describe an amorphous collection of individuals who have sought to influence Australian foreign policy in favour of Indonesia. The term was originally applied to a group of Indonesian experts at the Australian National University in the 1980s but expanded to include journalists, think tanks and key diplomats. The concept of the ‘pro-Jakarta lobby’ was developed largely through criticisms of Australia’s support for Indonesia’s sovereignty of East Timor and West Papua. Pro-Independence supporters were integral for creating the ‘lobby’ in their rhetoric and criticisms about the influence on Australian foreign policy. In these critical narratives, the ‘pro-Jakarta lobby’ supported a realist approach to relations with Indonesia during the years of President Suharto’s regime, which saw appeasement of Indonesia as paramount to values of democracy and human rights. The lobby was viewed as integral in embedding a form of ‘foreign policy exceptionalism’ towards Indonesia in Australian policy-making circles. However, little critical and scholarly attention has been paid to nature, aims, strategies and activities of the ‘pro-Jakarta lobby.' This paper engages with methodological issues of foreign policy analysis: what was the ‘pro-Jakarta lobby’? Why was it considered more successful than other activist groups in shaping policy? And how can its influence on Australia’s approach to Indonesia be tested in relation to other contingent factors shaping policy? In addressing these questions, this case study will assist in addressing a broader scholarly concern about the capacities of collectives or individuals in shaping and directing the foreign policies of states.

Keywords: foreign policy, interests groups, Australia, Indonesia

Procedia PDF Downloads 322
189 Jurisdiction Conflicts in Contracts of International Maritime Transport: The Application of the Forum Selection Clause in Brazilian Courts

Authors: Renan Caseiro De Almeida, Mateus Mello Garrute

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The world walks to be ever more globalised. This trend promotes an increase on the number of transnational commercial transactions. The main modal for carriage of goods is by sea, and many countries have their economies dependent on the maritime freightage – it could be because they exercise largely this activity or because they follow the tendency of using the maritime logistic widely. Among these ones, Brazil is included. This nation counts with sixteen ports with good capacities, which receive most of the international income by sea. It is estimated that 85 per cent of the total influx of goods in Brazil is by maritime modal, leaving mere 15 per cent for the other ones. This made it necessary to develop maritime law in international and national basis, to create a standard to be applied with the intention to harmonize the transnational carriage of goods by sea. Maritime contracts are very specific and have interesting peculiarities, but in their range, little research has been made on what causes the main divergences when it comes to international contracts: the jurisdiction conflict. Likewise any other international contract, it is common for the parties to set a forum selection clause to choose the forum which will be able to judge the litigations that could rise from a maritime transport contract and, consequently, also which law should be applied to the cases. However, the forum choice in Brazil has always been somewhat polemical – not only in the maritime law sphere - for sometimes national tribunals overlook the parties’ choice and call the competence for themselves. In this sense, it is interesting to mention that the Mexico Convention of 1994 about the law applicable to international contracts did not gain strength in Brazil, nor even reached the Congress to be considered for ratification. Furthermore, it is also noteworthy that Brazil has a new Civil Procedure Code, which was put into reinforcement in 2016 bringing new legal provisions specifically about the forum selection. This represented a mark in the national legal system in this matter. Therefore, this paper intends to give an insight through Brazilian jurisprudence, making an analysis of how this issue has been treated on litigations about maritime contracts in the national tribunals, as well as the solutions found by the Brazilian legal system for the jurisdiction conflicts in those cases. To achieve the expected results, the hypothetical-deductive method will be used in combination with researches on doctrine and legislations. Also, jurisprudential research and case law study will have a special role, since the main point of this paper is to verify and study the position of the courts in Brazil in a specific matter. As a country of civil law, the Brazilian judges and tribunals are very attached to the rules displayed on codes. However, the jurisprudential understanding has been changing during the years and with the advent of the new rules about the applicable law and forum selection clause, it is noticeable that new winds are being blown.

Keywords: applicable law, forum selection clause, international business, international maritime contracts, litigation in courts

Procedia PDF Downloads 252
188 Water Infrastructure Asset Management: A Comparative Analysis of Three Urban Water Utilities in South Africa

Authors: Elkington S. Mnguni

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Water and sanitation services in South Africa are characterized by both achievements and challenges. After the end of apartheid in 1994 the newly elected government faced the challenge of eradicating backlogs with respect to access to basic services, including water and sanitation. Capital investment made in the development of new water and sanitation infrastructure to provide basic services to previously disadvantaged communities has grown, to a certain extent, at the expense of investment in the operation and maintenance of new and existing infrastructure. Challenges resulting from aging infrastructure and poor plant performance highlight the need for investing in the maintenance, rehabilitation, and replacement of existing infrastructure to optimize the return on investment. Advanced water infrastructure asset management (IAM) is key to achieving adequate levels of service, particularly with regard to reliable and high quality drinking water supply, prevention of urban flooding, efficient use of natural resources and prevention of pollution and associated risks. Against this backdrop, this paper presents an appraisal of water and sanitation IAM systems in South Africa’s three utilities, being metropolitan cities in the Gauteng Province. About a quarter of the national population lives in the three rapidly urbanizing cities of Johannesburg, Ekurhuleni and Tshwane, located in a semi-arid region. A literature review has been done and field visits to some of the utility facilities are being conducted. Semi-structured interviews will be conducted with the three utilities. The following critical factors are being analysed in terms of compliance with the national Water Services IAM Strategy (2011) and other applicable legislation: asset registers; capacity of assets; current and predicted demand; funding availability / budget allocations; plans: operation & maintenance, renewal & replacement, and risk management; no-drop status (non-revenue water levels); blue drop status (water quality); green drop status (effluent quality); and skills availability. Some of the key challenges identified in the literature review include: funding constraints, Skills shortage, and wastewater treatment plants operating beyond their design capacities. These challenges will be verified during field visits and research interviews. Gaps between literature and practice will be identified and relevant recommendations made if necessary. The objective of this study is to contribute to the resolution of the challenges brought about by the backlogs in the operation and maintenance of water and sanitation assets in the country in general, and in the three cities in particular, thus improving the sustainability thereof.

Keywords: asset management, backlogs, levels of service, sustainability, water and sanitation infrastructure

Procedia PDF Downloads 202
187 Viscoelastic Behavior of Human Bone Tissue under Nanoindentation Tests

Authors: Anna Makuch, Grzegorz Kokot, Konstanty Skalski, Jakub Banczorowski

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Cancellous bone is a porous composite of a hierarchical structure and anisotropic properties. The biological tissue is considered to be a viscoelastic material, but many studies based on a nanoindentation method have focused on their elasticity and microhardness. However, the response of many organic materials depends not only on the load magnitude, but also on its duration and time course. Depth Sensing Indentation (DSI) technique has been used for examination of creep in polymers, metals and composites. In the indentation tests on biological samples, the mechanical properties are most frequently determined for animal tissues (of an ox, a monkey, a pig, a rat, a mouse, a bovine). However, there are rare reports of studies of the bone viscoelastic properties on microstructural level. Various rheological models were used to describe the viscoelastic behaviours of bone, identified in the indentation process (e. g Burgers model, linear model, two-dashpot Kelvin model, Maxwell-Voigt model). The goal of the study was to determine the influence of creep effect on the mechanical properties of human cancellous bone in indentation tests. The aim of this research was also the assessment of the material properties of bone structures, having in mind the energy aspects of the curve (penetrator loading-depth) obtained in the loading/unloading cycle. There was considered how the different holding times affected the results within trabecular bone.As a result, indentation creep (CIT), hardness (HM, HIT, HV) and elasticity are obtained. Human trabecular bone samples (n=21; mean age 63±15yrs) from the femoral heads replaced during hip alloplasty were removed and drained from alcohol of 1h before the experiment. The indentation process was conducted using CSM Microhardness Tester equipped with Vickers indenter. Each sample was indented 35 times (7 times for 5 different hold times: t1=0.1s, t2=1s, t3=10s, t4=100s and t5=1000s). The indenter was advanced at a rate of 10mN/s to 500mN. There was used Oliver-Pharr method in calculation process. The increase of hold time is associated with the decrease of hardness parameters (HIT(t1)=418±34 MPa, HIT(t2)=390±50 MPa, HIT(t3)= 313±54 MPa, HIT(t4)=305±54 MPa, HIT(t5)=276±90 MPa) and elasticity (EIT(t1)=7.7±1.2 GPa, EIT(t2)=8.0±1.5 GPa, EIT(t3)=7.0±0.9 GPa, EIT(t4)=7.2±0.9 GPa, EIT(t5)=6.2±1.8 GPa) as well as with the increase of the elastic (Welastic(t1)=4.11∙10-7±4.2∙10-8Nm, Welastic(t2)= 4.12∙10-7±6.4∙10-8 Nm, Welastic(t3)=4.71∙10-7±6.0∙10-9 Nm, Welastic(t4)= 4.33∙10-7±5.5∙10-9Nm, Welastic(t5)=5.11∙10-7±7.4∙10-8Nm) and inelastic (Winelastic(t1)=1.05∙10-6±1.2∙10-7 Nm, Winelastic(t2) =1.07∙10-6±7.6∙10-8 Nm, Winelastic(t3)=1.26∙10-6±1.9∙10-7Nm, Winelastic(t4)=1.56∙10-6± 1.9∙10-7 Nm, Winelastic(t5)=1.67∙10-6±2.6∙10-7)) reaction of materials. The indentation creep increased logarithmically (R2=0.901) with increasing hold time: CIT(t1) = 0.08±0.01%, CIT(t2) = 0.7±0.1%, CIT(t3) = 3.7±0.3%, CIT(t4) = 12.2±1.5%, CIT(t5) = 13.5±3.8%. The pronounced impact of creep effect on the mechanical properties of human cancellous bone was observed in experimental studies. While the description elastic-inelastic, and thus the Oliver-Pharr method for data analysis, may apply in few limited cases, most biological tissues do not exhibit elastic-inelastic indentation responses. Viscoelastic properties of tissues may play a significant role in remodelling. The aspect is still under an analysis and numerical simulations. Acknowledgements: The presented results are part of the research project founded by National Science Centre (NCN), Poland, no.2014/15/B/ST7/03244.

Keywords: bone, creep, indentation, mechanical properties

Procedia PDF Downloads 147
186 Tunable Crystallinity of Zinc Gallogermanate Nanoparticles via Organic Ligand-Assisted Biphasic Hydrothermal Synthesis

Authors: Sarai Guerrero, Lijia Liu

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Zinc gallogermanate (ZGGO) is a persistent phosphor that can emit in the near infrared (NIR) range once dopped with Cr³⁺ enabling its use for in-vivo deep-tissue bio-imaging. Such a property also allows for its application in cancer diagnosis and therapy. Given this, work into developing a synthetic procedure that can be done using common laboratory instruments and equipment as well as understanding ZGGO overall, is in demand. However, the ZGGO nanoparticles must have a size compatible for cell intake to occur while still maintaining sufficient photoluminescence. The nanoparticle must also be made biocompatible by functionalizing the surface for hydrophilic solubility and for high particle uniformity in the final product. Additionally, most research is completed on doped ZGGO, leaving a gap in understanding the base form of ZGGO. It also leaves a gap in understanding how doping affects the synthesis of ZGGO. In this work, the first step of optimizing the particle size via the crystalline size of ZGGO was done with undoped ZGGO using the organic acid, oleic acid (OA) for organic ligand-assisted biphasic hydrothermal synthesis. The effects of this synthesis procedure on ZGGO’s crystallinity were evaluated using Powder X-Ray Diffraction (PXRD). OA was selected as the capping ligand as experiments have shown it beneficial in synthesizing sub-10 nm zinc gallate (ZGO) nanoparticles as well as palladium nanocrystals and magnetite (Fe₃O₄) nanoparticles. Later it is possible to substitute OA with a different ligand allowing for hydrophilic solubility. Attenuated Total Reflection Fourier-Transform Infrared (ATR-FTIR) was used to investigate the surface of the nanoparticle to investigate and verify that OA had capped the nanoparticle. PXRD results showed that using this procedure led to improved crystallinity, comparable to the high-purity reagents used on the ZGGO nanoparticles. There was also a change in the crystalline size of the ZGGO nanoparticles. ATR-FTIR showed that once capped ZGGO cannot be annealed as doing so will affect the OA. These results point to this new procedure positively affecting the crystallinity of ZGGO nanoparticles. There are also repeatable implying the procedure is a reliable source of highly crystalline ZGGO nanoparticles. With this completed, the next step will be working on substituting the OA with a hydrophilic ligand. As these ligands effect the solubility of the nanoparticle as well as the pH that the nanoparticles can dissolve in, further research is needed to verify which ligand is best suited for preparing ZGGO for bio-imaging.

Keywords: biphasic hydrothermal synthesis, crystallinity, oleic acid, zinc gallogermanate

Procedia PDF Downloads 106
185 Numerical Investigation of Thermal Energy Storage Panel Using Nanoparticle Enhanced Phase Change Material for Micro-Satellites

Authors: Jelvin Tom Sebastian, Vinod Yeldho Baby

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In space, electronic devices are constantly attacked with radiation, which causes certain parts to fail or behave in unpredictable ways. To advance the thermal controllability for microsatellites, we need a new approach and thermal control system that is smaller than that on conventional satellites and that demand no electric power. Heat exchange inside the microsatellites is not that easy as conventional satellites due to the smaller size. With slight mass gain and no electric power, accommodating heat using phase change materials (PCMs) is a strong candidate for solving micro satellites' thermal difficulty. In other words, PCMs can absorb or produce heat in the form of latent heat, changing their phase and minimalizing the temperature fluctuation around the phase change point. The main restriction for these systems is thermal conductivity weakness of common PCMs. As PCM is having low thermal conductivity, it increases the melting and solidification time, which is not suitable for specific application like electronic cooling. In order to increase the thermal conductivity nanoparticles are introduced. Adding the nanoparticles in base PCM increases the thermal conductivity. Increase in weight concentration increases the thermal conductivity. This paper numerically investigates the thermal energy storage panel with nanoparticle enhanced phase change material. Silver nanostructure have increased the thermal properties of the base PCM, eicosane. Different weight concentration (1, 2, 3.5, 5, 6.5, 8, 10%) of silver enhanced phase change material was considered. Both steady state and transient analysis was performed to compare the characteristics of nanoparticle enhanced phase material at different heat loads. Results showed that in steady state, the temperature near the front panel reduced and temperature on NePCM panel increased as the weight concentration increased. With the increase in thermal conductivity more heat was absorbed into the NePCM panel. In transient analysis, it was found that the effect of nanoparticle concentration on maximum temperature of the system was reduced as the melting point of the material reduced with increase in weight concentration. But for the heat load of maximum 20W, the model with NePCM did not attain the melting point temperature. Therefore it showed that the model with NePCM is capable of holding more heat load. In order to study the heat load capacity double the load is given, maximum of 40W was given as first half of the cycle and the other is given constant OW. Higher temperature was obtained comparing the other heat load. The panel maintained a constant temperature for a long duration according to the NePCM melting point. In both the analysis, the uniformity of temperature of the TESP was shown. Using Ag-NePCM it allows maintaining a constant peak temperature near the melting point. Therefore, by altering the weight concentration of the Ag-NePCM it is possible to create an optimum operating temperature required for the effective working of the electronics components.

Keywords: carbon-fiber-reinforced polymer, micro/nano-satellite, nanoparticle phase change material, thermal energy storage

Procedia PDF Downloads 187
184 Evaluation of Batch Splitting in the Context of Load Scattering

Authors: S. Wesebaum, S. Willeke

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Production companies are faced with an increasingly turbulent business environment, which demands very high production volumes- and delivery date flexibility. If a decoupling by storage stages is not possible (e.g. at a contract manufacturing company) or undesirable from a logistical point of view, load scattering effects the production processes. ‘Load’ characterizes timing and quantity incidence of production orders (e.g. in work content hours) to workstations in the production, which results in specific capacity requirements. Insufficient coordination between load (demand capacity) and capacity supply results in heavy load scattering, which can be described by deviations and uncertainties in the input behavior of a capacity unit. In order to respond to fluctuating loads, companies try to implement consistent and realizable input behavior using the capacity supply available. For example, a uniform and high level of equipment capacity utilization keeps production costs down. In contrast, strong load scattering at workstations leads to performance loss or disproportionately fluctuating WIP, whereby the logistics objectives are affected negatively. Options for reducing load scattering are e.g. shifting the start and end dates of orders, batch splitting and outsourcing of operations or shifting to other workstations. This leads to an adjustment of load to capacity supply, and thus to a reduction of load scattering. If the adaptation of load to capacity cannot be satisfied completely, possibly flexible capacity must be used to ensure that the performance of a workstation does not decrease for a given load. Where the use of flexible capacities normally raises costs, an adjustment of load to capacity supply reduces load scattering and, in consequence, costs. In the literature you mostly find qualitative statements for describing load scattering. Quantitative evaluation methods that describe load mathematically are rare. In this article the authors discuss existing approaches for calculating load scattering and their various disadvantages such as lack of opportunity for normalization. These approaches are the basis for the development of our mathematical quantification approach for describing load scattering that compensates the disadvantages of the current quantification approaches. After presenting our mathematical quantification approach, the method of batch splitting will be described. Batch splitting allows the adaptation of load to capacity to reduce load scattering. After describing the method, it will be explicitly analyzed in the context of the logistic curve theory by Nyhuis using the stretch factor α1 in order to evaluate the impact of the method of batch splitting on load scattering and on logistic curves. The conclusion of this article will be to show how the methods and approaches presented can help companies in a turbulent environment to quantify the occurring work load scattering accurately and apply an efficient method for adjusting work load to capacity supply. In this way, the achievements of the logistical objectives are increased without causing additional costs.

Keywords: batch splitting, production logistics, production planning and control, quantification, load scattering

Procedia PDF Downloads 378
183 Epidemiological Data of Schistosoma haematobium Bilharzia in Rural and Urban Localities in the Republic of Congo

Authors: Jean Akiana, Digne Merveille Nganga Bouanga, Nardiouf Sjelin Nsana, Wilfrid Sapromet Ngoubili, Chyvanelle Ndous Akiridzo, Vishnou Reize Ampiri, Henri-Joseph Parra, Florence Fenollar, Didier Raoult, Oleg Mediannikov, Cheikh Sadhibou Sokhna

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Schistosoma haematobium schistosomiasis is an endemic disease in which the level of human exposure, incidence, and fatality attributed to it remains, unfortunately, high worldwide. The erection of hydroelectric infrastructures constitute a major factor in the emergence of this disease. In the context of the Republic of the Congo, which considers industrialization and modernization as two essential pillars of development, building the hydroelectric dams of Liouesso (19 Mw) and the feasibility studies of the dams of Chollet (600MW) in the Sangha, of Sounda (1000MW) in Kouilou and Kouembali (150MW) on Lefini is necessary to increase the country's energy capacities. Likewise, the urbanization of former endemic localities should take into account the maintenance of contamination points. However, health impact studies on schistosomiasis epidemiology in general and urinary bilharzia, in particular, have never been carried out in these areas, neither before nor after the erection of those dams. Participants benefited from an investigative questionnaire, urinalysis both by dipstick and urine filtrate examined under a microscope. Assessment of the genetic diversity of schistosoma species populations was considered as well as PCR analysis to confirm the test strip and microscopy tests. 405 participants were registered in five localities. The sampling was made up of a balanced population in terms of male/female ratio, which is around 1. The prevalence rate was 45% (55/123) in Nkayi, 10.40% (11/106) in Loudima, 1 case in Mbomo (West Cuvette), which would probably be imported, zero in Liouesso and Kabo. The highest oviuria (number of eggs per volume of urine) is 150 S. haematobium eggs/10ml in Nkayi, apart from the case of imported Mbomo, imported from Gabon, which has 160 S. haematobium eggs/10ml. The lowest oviuria was 2 S. haematobium eggs/10ml. Prevalence rates are still high in semi-urban areas (Nkayi). As praziquantel treatments are available and effective, it is important to step up mass treatment campaigns in high risk areas already largely initiated by the National Schistosomiasis Control Program. Prevalence rates are still high in semi-urban areas (Nkayi). As praziquantel treatments are available and effective, it is important to step up mass treatment campaigns in high risk areas already largely initiated by the National Schistosomiasis Control Program.

Keywords: Bilharzia, Schistosoma haematobium, oviuria, urbanization, Congo

Procedia PDF Downloads 128
182 Synergy Surface Modification for High Performance Li-Rich Cathode

Authors: Aipeng Zhu, Yun Zhang

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The growing grievous environment problems together with the exhaustion of energy resources put urgent demands for developing high energy density. Considering the factors including capacity, resource and environment, Manganese-based lithium-rich layer-structured cathode materials xLi₂MnO₃⋅(1-x)LiMO₂ (M = Ni, Co, Mn, and other metals) are drawing increasing attention due to their high reversible capacities, high discharge potentials, and low cost. They are expected to be one type of the most promising cathode materials for the next-generation Li-ion batteries (LIBs) with higher energy densities. Unfortunately, their commercial applications are hindered with crucial drawbacks such as poor rate performance, limited cycle life and continuous falling of the discharge potential. With decades of extensive studies, significant achievements have been obtained in improving their cyclability and rate performances, but they cannot meet the requirement of commercial utilization till now. One major problem for lithium-rich layer-structured cathode materials (LLOs) is the side reaction during cycling, which leads to severe surface degradation. In this process, the metal ions can dissolve in the electrolyte, and the surface phase change can hinder the intercalation/deintercalation of Li ions and resulting in low capacity retention and low working voltage. To optimize the LLOs cathode material, the surface coating is an efficient method. Considering the price and stability, Al₂O₃ was used as a coating material in the research. Meanwhile, due to the low initial Coulombic efficiency (ICE), the pristine LLOs was pretreated by KMnO₄ to increase the ICE. The precursor was prepared by a facile coprecipitation method. The as-prepared precursor was then thoroughly mixed with Li₂CO₃ and calcined in air at 500℃ for 5h and 900℃ for 12h to produce Li₁.₂[Ni₀.₂Mn₀.₆]O₂ (LNMO). The LNMO was then put into 0.1ml/g KMnO₄ solution stirring for 3h. The resultant was filtered and washed with water, and dried in an oven. The LLOs obtained was dispersed in Al(NO₃)₃ solution. The mixture was lyophilized to confer the Al(NO₃)₃ was uniformly coated on LLOs. After lyophilization, the LLOs was calcined at 500℃ for 3h to obtain LNMO@LMO@ALO. The working electrodes were prepared by casting the mixture of active material, acetylene black, and binder (polyvinglidene fluoride) dissolved in N-methyl-2-pyrrolidone with a mass ratio of 80: 15: 5 onto an aluminum foil. The electrochemical performance tests showed that the multiple surface modified materials had a higher initial Coulombic efficiency (84%) and better capacity retention (91% after 100 cycles) compared with that of pristine LNMO (76% and 80%, respectively). The modified material suggests that the KMnO₄ pretreat and Al₂O₃ coating can increase the ICE and cycling stability.

Keywords: Li-rich materials, surface coating, lithium ion batteries, Al₂O₃

Procedia PDF Downloads 109
181 Modeling of Geotechnical Data Using GIS and Matlab for Eastern Ahmedabad City, Gujarat

Authors: Rahul Patel, S. P. Dave, M. V Shah

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Ahmedabad is a rapidly growing city in western India that is experiencing significant urbanization and industrialization. With projections indicating that it will become a metropolitan city in the near future, various construction activities are taking place, making soil testing a crucial requirement before construction can commence. To achieve this, construction companies and contractors need to periodically conduct soil testing. This study focuses on the process of creating a spatial database that is digitally formatted and integrated with geotechnical data and a Geographic Information System (GIS). Building a comprehensive geotechnical Geo-database involves three essential steps. Firstly, borehole data is collected from reputable sources. Secondly, the accuracy and redundancy of the data are verified. Finally, the geotechnical information is standardized and organized for integration into the database. Once the Geo-database is complete, it is integrated with GIS. This integration allows users to visualize, analyze, and interpret geotechnical information spatially. Using a Topographic to Raster interpolation process in GIS, estimated values are assigned to all locations based on sampled geotechnical data values. The study area was contoured for SPT N-Values, Soil Classification, Φ-Values, and Bearing Capacity (T/m2). Various interpolation techniques were cross-validated to ensure information accuracy. The GIS map generated by this study enables the calculation of SPT N-Values, Φ-Values, and bearing capacities for different footing widths and various depths. This approach highlights the potential of GIS in providing an efficient solution to complex phenomena that would otherwise be tedious to achieve through other means. Not only does GIS offer greater accuracy, but it also generates valuable information that can be used as input for correlation analysis. Furthermore, this system serves as a decision support tool for geotechnical engineers. The information generated by this study can be utilized by engineers to make informed decisions during construction activities. For instance, they can use the data to optimize foundation designs and improve site selection. In conclusion, the rapid growth experienced by Ahmedabad requires extensive construction activities, necessitating soil testing. This study focused on the process of creating a comprehensive geotechnical database integrated with GIS. The database was developed by collecting borehole data from reputable sources, verifying its accuracy and redundancy, and organizing the information for integration. The GIS map generated by this study is an efficient solution that offers greater accuracy and generates valuable information that can be used as input for correlation analysis. It also serves as a decision support tool for geotechnical engineers, allowing them to make informed decisions during construction activities.

Keywords: arcGIS, borehole data, geographic information system (GIS), geo-database, interpolation, SPT N-value, soil classification, φ-value, bearing capacity

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180 Biodsorption as an Efficient Technology for the Removal of Phosphate, Nitrate and Sulphate Anions in Industrial Wastewater

Authors: Angel Villabona-Ortíz, Candelaria Tejada-Tovar, Andrea Viera-Devoz

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Wastewater treatment is an issue of vital importance in these times where the impacts of human activities are most evident, which have become essential tasks for the normal functioning of society. However, they put entire ecosystems at risk by time destroying the possibility of sustainable development. Various conventional technologies are used to remove pollutants from water. Agroindustrial waste is the product with the potential to be used as a renewable raw material for the production of energy and chemical products, and their use is beneficial since products with added value are generated from materials that were not used before. Considering the benefits that the use of residual biomass brings, this project proposes the use of agro-industrial residues from corn crops for the production of natural adsorbents whose purpose is aimed at the remediation of contaminated water bodies with large loads of nutrients. The adsorption capacity of two biomaterials obtained from the processing of corn stalks was evaluated by batch system tests. Biochar impregnated with sulfuric acid and thermally activated was synthesized. On the other hand, the cellulose was extracted from the corn stalks and chemically modified with cetyltrimethylammonium chloride in order to quaternize the surface of the adsorbent. The adsorbents obtained were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), infrared spectrometry with Fourier Transform (FTIR), analysis by Brunauer, Emmett and Teller method (BET) and X-ray Diffraction analysis ( XRD), which showed favorable characteristics for the cellulose extraction process. Higher adsorption capacities of the nutrients were obtained with the use of biochar, with phosphate being the anion with the best removal percentages. The effect of the initial adsorbate concentration was evaluated, with which it was shown that the Freundlich isotherm better describes the adsorption process in most systems. The adsorbent-phosphate / nitrate systems fit better to the Pseudo Primer Order kinetic model, while the adsorbent-sulfate systems showed a better fit to the Pseudo second-order model, which indicates that there are both physical and chemical interactions in the process. Multicomponent adsorption tests revealed that phosphate anions have a higher affinity for both adsorbents. On the other hand, the thermodynamic parameters standard enthalpy (ΔH °) and standard entropy (ΔS °) with negative results indicate the exothermic nature of the process, whereas the ascending values of standard Gibbs free energy (ΔG °). The adsorption process of anions with biocarbon and modified cellulose is spontaneous and exothermic. The use of the evaluated biomateriles is recommended for the treatment of industrial effluents contaminated with sulfate, nitrate and phosphate anions.

Keywords: adsorption, biochar, modified cellulose, corn stalks

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179 Beneficial Effects of Whey Protein Concentrate in Venous Thrombosis

Authors: Anna Tokajuk, Agnieszka Zakrzeska, Ewa Chabielska, Halina Car

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Whey is a by-product generated mainly in the production of cheese and casein. Powder forms of whey are used widely in the food industry as well as a high-protein food for infants, for convalescents, by athletes and especially by bodybuilders to increase muscle mass during exercise. Whey protein concentrate-80 (WPC-80) is a source of bioactive peptides with beneficial effects on the cardiovascular system. It is known that whey proteins health beneficial properties include antidiabetic, blood pressure lowering, improving cardiovascular system function, antibacterial, antiviral and other effects. To study its influence on the development of thrombosis, venous thrombosis model was performed according to the protocol featured by Reyers with modification by Chabielska and Gromotowicz. Male Wistar-Crl: WI (Han) rats from researched groups were supplemented with two doses of WPC-80 (0.3 or 0.5 g/kg) for 7, 14 or 21 days and after these periods, one-hour venous thrombosis model was performed. Control group received 0.9 % NaCl solution and was sham operated. The statistical significance of results was computed by Mann – Whitney’s test. We observed that thrombus weight was decreased in animals obtaining WPC-8080 and that was statistically significant in 14 and 21-day supplemented groups. Blood count parameters did not differ significantly in rats with and without thrombosis induction whether they were fed with WPC-80 or not. Moreover, the number of platelets (PLT) was within the normal range in each group. The examined coagulation parameters in rats of the control groups were within normal limits. After WPC-80 supplementation there was the tendency to prolonged activated partial thromboplastin time (aPTT), but in comparison, the results did not turn out significant. In animals that received WPC-80 0.3 g·kg-1 for 21 days with and without induced thrombosis, prothrombin time (PT) and an international normalized ratio (INR) was somewhat decreased, remaining within the normal range, but the nature and significance of this observation are beyond the framework of the current study. Additionally, fibrinogen and thrombin time (TT) did not differ significantly between groups. Therefore the exact effect of WPC-80 on coagulation system is still elusive and requires further thorough research including mechanisms of action. Determining the potential clinical application of WPC-80 requires the selection of the optimal dose and duration of supplementation.

Keywords: antithrombotic, rats, venous thrombosis, WPC-80

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178 Collaborative Management Approach for Logistics Flow Management of Cuban Medicine Supply Chain

Authors: Ana Julia Acevedo Urquiaga, Jose A. Acevedo Suarez, Ana Julia Urquiaga Rodriguez, Neyfe Sablon Cossio

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Despite the progress made in logistics and supply chains fields, it is unavoidable the development of business models that use efficiently information to facilitate the integrated logistics flows management between partners. Collaborative management is an important tool for materializing the cooperation between companies, as a way to achieve the supply chain efficiency and effectiveness. The first face of this research was a comprehensive analysis of the collaborative planning on the Cuban companies. It is evident that they have difficulties in supply chains planning where production, supplies and replenishment planning are independent tasks, as well as logistics and distribution operations. Large inventories generate serious financial and organizational problems for entities, demanding increasing levels of working capital that cannot be financed. Problems were found in the efficient application of Information and Communication Technology on business management. The general objective of this work is to develop a methodology that allows the deployment of a planning and control system in a coordinated way on the medicine’s logistics system in Cuba. To achieve these objectives, several mechanisms of supply chain coordination, mathematical programming models, and other management techniques were analyzed to meet the requirements of collaborative logistics management in Cuba. One of the findings is the practical and theoretical inadequacies of the studied models to solve the current situation of the Cuban logistics systems management. To contribute to the tactical-operative management of logistics, the Collaborative Logistics Flow Management Model (CLFMM) is proposed as a tool for the balance of cycles, capacities, and inventories, always to meet the final customers’ demands in correspondence with the service level expected by these. The CLFMM has as center the supply chain planning and control system as a unique information system, which acts on the processes network. The development of the model is based on the empirical methods of analysis-synthesis and the study cases. Other finding is the demonstration of the use of a single information system to support the supply chain logistics management, allows determining the deadlines and quantities required in each process. This ensures that medications are always available to patients and there are no faults that put the population's health at risk. The simulation of planning and control with the CLFMM in medicines such as dipyrone and chlordiazepoxide, during 5 months of 2017, permitted to take measures to adjust the logistic flow, eliminate delayed processes and avoid shortages of the medicines studied. As a result, the logistics cycle efficiency can be increased to 91%, the inventory rotation would increase, and this results in a release of financial resources.

Keywords: collaborative management, medicine logistic system, supply chain planning, tactical-operative planning

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177 From Shelf to Shell - The Corporate Form in the Era of Over-Regulation

Authors: Chrysthia Papacleovoulou

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The era of de-regulation, off-shore and tax haven jurisdictions, and shelf companies has come to an end. The usage of complex corporate structures involving trust instruments, special purpose vehicles, holding-subsidiaries in offshore haven jurisdictions, and taking advantage of tax treaties is soaring. States which raced to introduce corporate friendly legislation, tax incentives, and creative international trust law in order to attract greater FDI are now faced with regulatory challenges and are forced to revisit the corporate form and its tax treatment. The fiduciary services industry, which dominated over the last 3 decades, is now striving to keep up with the new regulatory framework as a result of a number of European and international legislative measures. This article considers the challenges to the company and the corporate form as a result of the legislative measures on tax planning and tax avoidance, CRS reporting, FATCA, CFC rules, OECD’s BEPS, the EU Commission's new transparency rules for intermediaries that extends to tax advisors, accountants, banks & lawyers who design and promote tax planning schemes for their clients, new EU rules to block artificial tax arrangements and new transparency requirements for financial accounts, tax rulings and multinationals activities (DAC 6), G20's decision for a global 15% minimum corporate tax and banking regulation. As a result, states are found in a race of over-regulation and compliance. These legislative measures constitute a global up-side down tax-harmonisation. Through the adoption of the OECD’s BEPS, states agreed to an international collaboration to end tax avoidance and reform international taxation rules. Whilst the idea was to ensure that multinationals would pay their fair share of tax everywhere they operate, an indirect result of the aforementioned regulatory measures was to attack private clients-individuals who -over the past 3 decades- used the international tax system and jurisdictions such as Marshal Islands, Cayman Islands, British Virgin Islands, Bermuda, Seychelles, St. Vincent, Jersey, Guernsey, Liechtenstein, Monaco, Cyprus, and Malta, to name but a few, to engage in legitimate tax planning and tax avoidance. Companies can no longer maintain bank accounts without satisfying the real substance test. States override the incorporation doctrine theory and apply a real seat or real substance test in taxing companies and their activities, targeting even the beneficial owners personally with tax liability. Tax authorities in civil law jurisdictions lift the corporate veil through the public registries of UBO Registries and Trust Registries. As a result, the corporate form and the doctrine of limited liability are challenged in their core. Lastly, this article identifies the development of new instruments, such as funds and private placement insurance policies, and the trend of digital nomad workers. The baffling question is whether industry and states can meet somewhere in the middle and exit this over-regulation frenzy.

Keywords: company, regulation, TAX, corporate structure, trust vehicles, real seat

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176 The Digital Transformation of Life Insurance Sales in Iran With the Emergence of Personal Financial Planning Robots; Opportunities and Challenges

Authors: Pedram Saadati, Zahra Nazari

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Anticipating and identifying future opportunities and challenges facing industry activists for the emergence and entry of new knowledge and technologies of personal financial planning, and providing practical solutions is one of the goals of this research. For this purpose, a future research tool based on receiving opinions from the main players of the insurance industry has been used. The research method in this study was in 4 stages; including 1- a survey of the specialist salesforce of life insurance in order to identify the variables 2- the ranking of the variables by experts selected by a researcher-made questionnaire 3- holding a panel of experts with the aim of understanding the mutual effects of the variables and 4- statistical analyzes of the mutual effects matrix in Mick Mac software is done. The integrated analysis of influencing variables in the future has been done with the method of Structural Analysis, which is one of the efficient and innovative methods of future research. A list of opportunities and challenges was identified through a survey of best-selling life insurance representatives who were selected by snowball sampling. In order to prioritize and identify the most important issues, all the issues raised were sent to selected experts who were selected theoretically through a researcher-made questionnaire. The respondents determined the importance of 36 variables through scoring, so that the prioritization of opportunity and challenge variables can be determined. 8 of the variables identified in the first stage were removed by selected experts, and finally, the number of variables that could be examined in the third stage became 28 variables, which, in order to facilitate the examination, were divided into 6 categories, respectively, 11 variables of organization and management. Marketing and sales 7 cases, social and cultural 6 cases, technological 2 cases, rebranding 1 case and insurance 1 case were divided. The reliability of the researcher-made questionnaire was confirmed with the Cronbach's alpha test value of 0.96. In the third stage, by forming a panel consisting of 5 insurance industry experts, the consensus of their opinions about the influence of factors on each other and the ranking of variables was entered into the matrix. The matrix included the interrelationships of 28 variables, which were investigated using the structural analysis method. By analyzing the data obtained from the matrix by Mic Mac software, the findings of the research indicate that the categories of "correct training in the use of the software, the weakness of the technology of insurance companies in personalizing products, using the approach of equipping the customer, and honesty in declaring no need Customer to Insurance", the most important challenges of the influencer and the categories of "salesforce equipping approach, product personalization based on customer needs assessment, customer's pleasant experience of being consulted with consulting robots, business improvement of the insurance company due to the use of these tools, increasing the efficiency of the issuance process and optimal customer purchase" were identified as the most important opportunities for influence.

Keywords: personal financial planning, wealth management, advisor robots, life insurance, digital transformation

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