Search results for: reactive routing protocol
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2136

Search results for: reactive routing protocol

1596 Resilience-Based Emergency Bridge Inspection Routing and Repair Scheduling under Uncertainty

Authors: Zhenyu Zhang, Hsi-Hsien Wei

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Highway network systems play a vital role in disaster response for disaster-damaged areas. Damaged bridges in such network systems can impede disaster response by disrupting transportation of rescue teams or humanitarian supplies. Therefore, emergency inspection and repair of bridges to quickly collect damage information of bridges and recover the functionality of highway networks is of paramount importance to disaster response. A widely used measure of a network’s capability to recover from disasters is resilience. To enhance highway network resilience, plenty of studies have developed various repair scheduling methods for the prioritization of bridge-repair tasks. These methods assume that repair activities are performed after the damage to a highway network is fully understood via inspection, although inspecting all bridges in a regional highway network may take days, leading to the significant delay in repairing bridges. In reality, emergency repair activities can be commenced as soon as the damage data of some bridges that are crucial to emergency response are obtained. Given that emergency bridge inspection and repair (EBIR) activities are executed simultaneously in the response phase, the real-time interactions between these activities can occur – the blockage of highways due to repair activities can affect inspection routes which in turn have an impact on emergency repair scheduling by providing real-time information on bridge damages. However, the impact of such interactions on the optimal emergency inspection routes (EIR) and emergency repair schedules (ERS) has not been discussed in prior studies. To overcome the aforementioned deficiencies, this study develops a routing and scheduling model for EBIR while accounting for real-time inspection-repair interactions to maximize highway network resilience. A stochastic, time-dependent integer program is proposed for the complex and real-time interacting EBIR problem given multiple inspection and repair teams at locations as set post-disaster. A hybrid genetic algorithm that integrates a heuristic approach into a traditional genetic algorithm to accelerate the evolution process is developed. Computational tests are performed using data from the 2008 Wenchuan earthquake, based on a regional highway network in Sichuan, China, consisting of 168 highway bridges on 36 highways connecting 25 cities/towns. The results show that the simultaneous implementation of bridge inspection and repair activities can significantly improve the highway network resilience. Moreover, the deployment of inspection and repair teams should match each other, and the network resilience will not be improved once the unilateral increase in inspection teams or repair teams exceeds a certain level. This study contributes to both knowledge and practice. First, the developed mathematical model makes it possible for capturing the impact of real-time inspection-repair interactions on inspection routing and repair scheduling and efficiently deriving optimal EIR and ERS on a large and complex highway network. Moreover, this study contributes to the organizational dimension of highway network resilience by providing optimal strategies for highway bridge management. With the decision support tool, disaster managers are able to identify the most critical bridges for disaster management and make decisions on proper inspection and repair strategies to improve highway network resilience.

Keywords: disaster management, emergency bridge inspection and repair, highway network, resilience, uncertainty

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1595 Dynamic Communications Mapping in NoC-Based Heterogeneous MPSoCs

Authors: M. K. Benhaoua, A. K. Singh, A. E. H. Benyamina

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In this paper, we propose heuristic for dynamic communications mapping that considers the placement of communications in order to optimize the overall performance. The mapping technique uses a newly proposed Algorithm to place communications between the tasks. The placement we propose of the communications leads to a better optimization of several performance metrics (time and energy consumption). Experimental results show that the proposed mapping approach provides significant performance improvements when compared to those using static routing.

Keywords: Multi-Processor Systems-on-Chip (MPSoCs), Network-on-Chip (NoC), heterogeneous architectures, dynamic mapping heuristics

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1594 Proposal of Optimality Evaluation for Quantum Secure Communication Protocols by Taking the Average of the Main Protocol Parameters: Efficiency, Security and Practicality

Authors: Georgi Bebrov, Rozalina Dimova

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In the field of quantum secure communication, there is no evaluation that characterizes quantum secure communication (QSC) protocols in a complete, general manner. The current paper addresses the problem concerning the lack of such an evaluation for QSC protocols by introducing an optimality evaluation, which is expressed as the average over the three main parameters of QSC protocols: efficiency, security, and practicality. For the efficiency evaluation, the common expression of this parameter is used, which incorporates all the classical and quantum resources (bits and qubits) utilized for transferring a certain amount of information (bits) in a secure manner. By using criteria approach whether or not certain criteria are met, an expression for the practicality evaluation is presented, which accounts for the complexity of the QSC practical realization. Based on the error rates that the common quantum attacks (Measurement and resend, Intercept and resend, probe attack, and entanglement swapping attack) induce, the security evaluation for a QSC protocol is proposed as the minimum function taken over the error rates of the mentioned quantum attacks. For the sake of clarity, an example is presented in order to show how the optimality is calculated.

Keywords: quantum cryptography, quantum secure communcation, quantum secure direct communcation security, quantum secure direct communcation efficiency, quantum secure direct communcation practicality

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1593 Assessment of in vitro Antioxidant and Anti-Inflammatory Potentials of Methanol Extract of Chrysophyllum albidum Cotyledon

Authors: Christianah Adebimpe Dare, Nelson Oghenebrorhie Elvis

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This study was aimed at analysing the phytochemicals in Chrysophyllum albidum cotyledon extract and their in vitro antioxidant and anti-inflammatory effects. The star apple fruit was bought at Igbona market Osogbo, Osun State, Nigeria. The seed from the fruit was removed and defatted. The residue was exhaustively extracted with methanol. The Chrysophyllum albidum cotyledon methanol extract (CCME) was phytochemically screened, flavonoids and phenol contents, antioxidant and anti-inflammatory assays were carried out on the extract using standard procedures. Phytochemicals analysis revealed the presence of steroids, tannins, flavonoid, saponin, triterpenes, and xanthoproteins. The phenolic concentration, total flavonoids concentration, and total sugar concentration were found to be 26.72 ± 0.048 µgTAE/mg, 23.12 ± 1.92µg of Rutin equivalent (RTE)/mg (10.49 ± 1.12µg of Quercetin equivalent (QE/mg) and 778.38 ± 12.82 µg of glucose/ml, respectively. The extract demonstrated significant inhibitory effect compared with the standards as potent antioxidant with percentage inhibition of DPPH as 38.10 %-39.51 %, lipid peroxidation as 45.85 %-65.85 %; ferric reducing power showed linear correlation to the standard and the anti-inflammatory potential with 22.06 %-26.37 % protection of the human red blood membrane and the percentage inhibition of denaturation of albumin 3.42 %-7.32 %. The study showed that C. albidum cotyledon methanol extract is a potent antioxidant and anti-inflammatory agent to combat oxidative stress and pathological diseases caused by reactive species.

Keywords: albumin denaturation, free radicals, lipid peroxidation, reactive species

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1592 Clay Effect on PET/Clay and PEN/Clay Nanocomposites Properties

Authors: F. Zouai, F. Z. Benabid, S. Bouhelal, D. Benachour

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Reinforced plastics or nanocomposites have attracted considerable attention in scientific and industrial fields because a very small amount of clay can significantly improve the properties of the polymer. The polymeric matrices used in this work are two saturated polyesters, i.e., polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). The success of processing compatible blends, based on poly(ethylene terephthalate) (PET)/poly(ethylene naphthalene) (PEN)/clay nanocomposites in one step by reactive melt extrusion is described. Untreated clay was first purified and functionalized ‘in situ’ with a compound based on an organic peroxide/ sulfur mixture and (tetramethylthiuram disulfide) as the activator for sulfur. The PET and PEN materials were first separately mixed in the molten state with functionalized clay. The PET/4 wt% clay and PEN/7.5 wt% clay compositions showed total exfoliation. These compositions, denoted nPET and nPEN, respectively, were used to prepare new n(PET/PEN) nanoblends in the same mixing batch. The n(PET/PEN) nanoblends were compared to neat PET/PEN blends. The blends and nanocomposites were characterized using various techniques. Microstructural and nanostructural properties were investigated. Fourier transform infrared spectroscopy (FTIR) results showed that the exfoliation of tetrahedral clay nanolayers is complete, and the octahedral structure totally disappears. It was shown that total exfoliation, confirmed by wide-angle X-ray scattering (WAXS) measurements, contributes to the enhancement of impact strength and tensile modulus. In addition, WAXS results indicated that all samples are amorphous. The differential scanning calorimetry (DSC) study indicated the occurrence of one glass transition temperature Tg, one crystallization temperature Tc and one melting temperature Tm for every composition.

Keywords: exfoliation, DRX, DSC, montmorillonite, nanocomposites, PEN, PET, plastograph, reactive melt-mixing

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1591 Independent Control over Surface Charge and Wettability Using Polyelectrolyte Architecture

Authors: Shanshan Guo, Xiaoying Zhu, Dominik Jańczewski, Koon Gee Neoh

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Surface charge and wettability are two prominent physical factors governing cell adhesion and have been extensively studied in the literature. However, a comparison between the two driving forces in terms of their independent and cooperative effects in affecting cell adhesion is rarely explored on a systematic and quantitative level. Herein, we formulate a protocol which allows two-dimensional and independent control over both surface charge and wettability. This protocol enables the unambiguous comparison of the effects of these two properties on cell adhesion. This strategy is implemented by controlling both the relative thickness of polyion layers in the layer-by-layer assembly and the polyion side chain chemical structures. The 2D property matrix spans surface isoelectric point ranging from 5 to 9 and water contact angle from 35º to 70º, with other interferential factors (e.g. roughness) eliminated. The interplay between these two surface variables influences 3T3 fibroblast cell adhesion. The results show that both surface charge and wettability have an effect on its adhesion. The combined effects of positive charge and hydrophilicity led to the highest cell adhesion whereas negative charge and hydrophobicity led to the lowest cell adhesion. Our design strategy can potentially form the basis for studying the distinct behaviors of electrostatic force or wettability driven interfacial phenomena and serving as a reference in future studies assessing cell adhesion to surfaces with known charge and wettability within the property range studied here.

Keywords: cell adhesion, layer-by-layer, surface charge, surface wettability

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1590 A Case Study of Alkali-Silica Reaction Induced Consistent Damage and Strength Degradation Evaluation in a Textile Mill Building Due to Slow-Reactive Aggregates

Authors: Ahsan R. Khokhar, Fizza Hassan

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Alkali-Silica Reaction (ASR) has been recognized as a potential cause of concrete degradation in the world since the 1940s. In Pakistan, mega hydropower structures like dams, weirs constructed from aggregates extracted from a local riverbed exhibited different levels of alkali-silica reactivity over an extended service period. The concrete expansion potential due to such aggregates has been categorized as slow-reactive. Apart from hydropower structures, ASR existence has been identified in the concrete structural elements of a Textile Mill building which used aggregates extracted from the nearby riverbed. The original structure of the Textile Mill was erected in the 80s with the addition of a textile ‘sizing and wrapping’ hall constructed in the 90s. In the years to follow, intensive spalling was observed in the structural members of the subject hall; enough to threat to the overall stability of the building. Limitations such as incomplete building data posed hurdles during the detailed structural investigation. The paper lists observations made while assessing the extent of damage and its effect on the building hall structure. Core testing and Petrographic tests were carried out as per the ASTM standards for strength degradation analysis followed by the identifying its root cause. Results confirmed significant structural strength reduction because of ASR which necessitated the formulation of an immediate re-strengthening solution. The paper also discusses the possible tracks of rehabilitative measures which are being adapted to stabilize the structure and seize further concrete expansion.

Keywords: Alkali-Silica Reaction (ASR), concrete strength degradation, damage assessment, damage evaluation

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1589 A Protocol of Procedures and Interventions to Accelerate Post-Earthquake Reconstruction

Authors: Maria Angela Bedini, Fabio Bronzini

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The Italian experiences, positive and negative, of the post-earthquake are conditioned by long times and structural bureaucratic constraints, also motivated by the attempt to contain mafia infiltration and corruption. The transition from the operational phase of the emergency to the planning phase of the reconstruction project is thus hampered by a series of inefficiencies and delays, incompatible with the need for rapid recovery of the territories in crisis. In fact, intervening in areas affected by seismic events means at the same time associating the reconstruction plan with an urban and territorial rehabilitation project based on strategies and tools in which prevention and safety play a leading role in the regeneration of territories in crisis and the return of the population. On the contrary, the earthquakes that took place in Italy have instead further deprived the territories affected of the minimum requirements for habitability, in terms of accessibility and services, accentuating the depopulation process, already underway before the earthquake. The objective of this work is to address with implementing and programmatic tools the procedures and strategies to be put in place, today and in the future, in Italy and abroad, to face the challenge of the reconstruction of activities, sociality, services, risk mitigation: a protocol of operational intentions and firm points, open to a continuous updating and implementation. The methodology followed is that of the comparison in a synthetic form between the different Italian experiences of the post-earthquake, based on facts and not on intentions, to highlight elements of excellence or, on the contrary, damage. The main results obtained can be summarized in technical comparison cards on good and bad practices. With this comparison, we intend to make a concrete contribution to the reconstruction process, certainly not only related to the reconstruction of buildings but privileging the primary social and economic needs. In this context, the recent instrument applied in Italy of the strategic urban and territorial SUM (Minimal Urban Structure) and the strategic monitoring process become dynamic tools for supporting reconstruction. The conclusions establish, by points, a protocol of interventions, the priorities for integrated socio-economic strategies, multisectoral and multicultural, and highlight the innovative aspects of 'inversion' of priorities in the reconstruction process, favoring the take-off of 'accelerator' interventions social and economic and a more updated system of coexistence with risks. In this perspective, reconstruction as a necessary response to the calamitous event can and must become a unique opportunity to raise the level of protection from risks and rehabilitation and development of the most fragile places in Italy and abroad.

Keywords: an operational protocol for reconstruction, operational priorities for coexistence with seismic risk, social and economic interventions accelerators of building reconstruction, the difficult post-earthquake reconstruction in Italy

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1588 Removal Capacity of Activated Carbon (AC) by Combining AC and Titanium Dioxide (TIO₂) in a Photocatalytically Regenerative Activated Carbon

Authors: Hanane Belayachi, Sarra Bourahla, Amel Belayachi, Fadela Nemchi, Mostefa Belhakem

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The most used techniques to remove pollutants from wastewater are adsorption onto activated carbon (AC) and oxidation using a photocatalyst slurry. The aim of this work is to eliminate such drawbacks by combining AC and titanium dioxide (TiO₂) in a photocatalytically Regenerative Activated Carbon. Anatase titania was deposited on powder-activated carbon made from grape seeds by the impregnation method, and then the composite photocatalyst was employed for the removal of reactive black 5, which is an anionic azo dye, from water. The AGS/TiO₂ was characterized by BET, MEB, RDX and optical absorption spectroscopy. The BET surface area and the pore structure of composite photocatalysts (AGS/TiO₂) and activated grape seeds (AGS) were evaluated from nitrogen adsorption data at 77 K in relation to process conditions. Our results indicate that the photocatalytic activity of AGS/TiO₂ was much higher than single-phase titania. The adsorption equilibrium of reactive black 5 from aqueous solutions on the examined materials was investigated. Langmuir, Freundlich, and Redlich–Petersen models were fitted to experimental equilibrium data, and their goodness of fit is compared. The degradation kinetics fitted well to the Langmuir-Hinselwood pseudo first order rate low. The photocatalytic activity of AGS/TiO₂ was much higher than virgin TiO₂. Chemical oxygen demand (COD) removal was measured at regular intervals to quantify the mineralization of the dye. Above 96% mineralization was observed. These results suggest that UV-irradiated TiO₂ immobilized on activated carbon may be considered an adequate process for the treatment of diluted colored textile wastewater.

Keywords: activated carbon, pollutant, catalysis, TiO₂

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1587 Islamic Banking Adoption Model from Technology Prospective

Authors: Amer Alzaidi

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Islamic banking is an alternative solution to those people who are worried about Riba (interest) in all forms of transaction while using banking services and products. Today, banks around the world have Islamic banking services and products the in one form or another. The use of Islamic banking is not only restricted to Muslims world but have reached to non-Muslim countries like UK, USA, Australia and Canada as well. Compared to conventional banking, the adoption rate of Islamic banking is low because of unawareness of customers, financial cost, and performance issues. The interest in Islamic banking by financial institutions as well as low adoption rate motivated us to look this matter into detail in order to identify Critical Success Factors, which are positively motivating customers to use Islamic banking services/ products and Critical Risk Factors, which have significantly negative effect on the adoption of Islamic banking. The CSFs and CRFs will be initially identified from the literature using methodology called Systematic Literature Review, followed by the empirical analysis of these factors using survey research method. Later, we will develop Islamic Banking Adoption Model (IBAM) to help banks to assess their Islamic banking strategic positioning and to improve their operational efficiency. The first potential contribution of this research study will be the development of IBAM protocol that will provide us guidelines for conducting our actual SLR. The second major contribution of this research will be the development of Islamic Banking Adoption Model (IBAM), and the third contribution of this research study will be the evaluation of the developed IBMA.

Keywords: Islamic banking, adoption model, protocol, technology

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1586 Comparison of Various Policies under Different Maintenance Strategies on a Multi-Component System

Authors: Demet Ozgur-Unluakin, Busenur Turkali, Ayse Karacaorenli

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Maintenance strategies can be classified into two types, which are reactive and proactive, with respect to the time of the failure and maintenance. If the maintenance activity is done after a breakdown, it is called reactive maintenance. On the other hand, proactive maintenance, which is further divided as preventive and predictive, focuses on maintaining components before a failure occurs to prevent expensive halts. Recently, the number of interacting components in a system has increased rapidly and therefore, the structure of the systems have become more complex. This situation has made it difficult to provide the right maintenance decisions. Herewith, determining effective decisions has played a significant role. In multi-component systems, many methodologies and strategies can be applied when a component or a system has already broken down or when it is desired to identify and avoid proactively defects that could lead to future failure. This study focuses on the comparison of various maintenance strategies on a multi-component dynamic system. Components in the system are hidden, although there exists partial observability to the decision maker and they deteriorate in time. Several predefined policies under corrective, preventive and predictive maintenance strategies are considered to minimize the total maintenance cost in a planning horizon. The policies are simulated via Dynamic Bayesian Networks on a multi-component system with different policy parameters and cost scenarios, and their performances are evaluated. Results show that when the difference between the corrective and proactive maintenance cost is low, none of the proactive maintenance policies is significantly better than the corrective maintenance. However, when the difference is increased, at least one policy parameter for each proactive maintenance strategy gives significantly lower cost than the corrective maintenance.

Keywords: decision making, dynamic Bayesian networks, maintenance, multi-component systems, reliability

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1585 Performance Analysis of Hierarchical Agglomerative Clustering in a Wireless Sensor Network Using Quantitative Data

Authors: Tapan Jain, Davender Singh Saini

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Clustering is a useful mechanism in wireless sensor networks which helps to cope with scalability and data transmission problems. The basic aim of our research work is to provide efficient clustering using Hierarchical agglomerative clustering (HAC). If the distance between the sensing nodes is calculated using their location then it’s quantitative HAC. This paper compares the various agglomerative clustering techniques applied in a wireless sensor network using the quantitative data. The simulations are done in MATLAB and the comparisons are made between the different protocols using dendrograms.

Keywords: routing, hierarchical clustering, agglomerative, quantitative, wireless sensor network

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1584 Ex Situ Conservation of Neutraceutical Banana-Musa paradisiaca cv. Karibale Monthan

Authors: V. Krishna, Shashikumar

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Edible Bananas (Musa spp.) are the major staple food for rural and urban consumers in India and an important source of rural income. The cultivar Musa paradisiaca cv. Karibale Monthan is an endemic cultivar of Malnad region of Karnataka and used as a glomolueroprotective neutraceutical to solve kidney problems. The protocol for mass multiplication of plantlets for this indigenous banana cultivar Karibale Monthan has not yet been standardized so far. In the present study, an attempt has been made to develop high frequency in vitro regeneration protocol and evaluation of morphoagronomic characteristics in the farmyard. The high frequency shoot initiation (93.33 %) was recorded at the synergetic effect of BAP (2 to 8mg/L), TDZ (0.1 to 1.2mg/L) and coconut water (0.1 to 1.2ml/L). It was optimized at the concentration 5 mg/l BAP, 0.5 mg/l TDZ and 0.5 ml/l coconut water with 15.90 ± 1.66 frequency of shoots per propagule. Supplementation of 1.0 mg/l IBA induces 5.33 ± 1.21 numbers of roots with a mean root length of 7.50 ± 1.87 roots. 99% of plantlets with distinct roots and shoots were successfully acclimatized in the green house and transferred to the field to evaluate the agro-morphological variations. The micropropagated plants showed significantly higher morphometric values for height of the plant (16.80±2.17), number of leaves (12.40±1.14), length of the bunch (56.20±2.17), weight of the bunch (13.60±1.14), number of hands in a bunch (11.40±1.14) and girth of the pseudostem (49.80±1.48) when compared with in vivo plants.

Keywords: banana cv. Karibale Monthan, neutraceutical, high-frequency regeneration, morphometric evaluation

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1583 Trafficking of Women and Children and Solutions to Combat It: The Case of Nigeria

Authors: Olatokunbo Yakeem

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Human trafficking is a crime against gross violations of human rights. Trafficking in persons is a severe socio-economic dilemma that affects the national and international dimensions. Human trafficking or modern-day-slavery emanated from slavery, and it has been in existence before the 6ᵗʰ century. Today, no country is exempted from dehumanizing human beings, and as a result, it has been an international issue. The United Nations (UN) presented the International Protocol to fight human trafficking worldwide, which brought about the international definition of human trafficking. The protocol is to prevent, suppress, and punish trafficking in persons, especially women and children. The trafficking protocol has a link with transnational organised crime rather than migration. Over a hundred and fifty countries nationwide have enacted their criminal and panel code trafficking legislation from the UN trafficking protocol. Sex trafficking is the most common type of exploitation of women and children. Other forms of this crime involve exploiting vulnerable victims through forced labour, child involvement in warfare, domestic servitude, debt bondage, and organ removal for transplantation. Trafficking of women and children into sexual exploitation represents the highest form of human trafficking than other types of exploitation. Trafficking of women and children can either happen internally or across the border. It affects all kinds of people, regardless of their race, social class, culture, religion, and education levels. However, it is more of a gender-based issue against females. Furthermore, human trafficking can lead to life-threatening infections, mental disorders, lifetime trauma, and even the victim's death. The study's significance is to explore why the root causes of women and children trafficking in Nigeria are based around poverty, entrusting children in the hands of relatives and friends, corruption, globalization, weak legislation, and ignorance. The importance of this study is to establish how the national, regional, and international organisations are using the 3P’s Protection, Prevention, and Prosecution) to tackle human trafficking. The methodology approach for this study will be a qualitative paradigm. The rationale behind this selection is that the qualitative method will identify the phenomenon and interpret the findings comprehensively. The data collection will take the form of semi-structured in-depth interviews through telephone and email. The researcher will use a descriptive thematic analysis to analyse the data by using complete coding. In summary, this study aims to recommend to the Nigerian federal government to include human trafficking as a subject in their educational curriculum for early intervention to prevent children from been coerced by criminal gangs. And the research aims to find the root causes of women and children trafficking. Also, to look into the effectiveness of the strategies in place to eradicate human trafficking globally. In the same vein, the research objective is to investigate how the anti-trafficking bodies such as law enforcement and NGOs collaborate to tackle the upsurge in human trafficking.

Keywords: children, Nigeria, trafficking, women

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1582 Hardware in the Loop Platform for Virtual Commissioning: Case Study of a Hydraulic-Press Model Simulated in Real-Time

Authors: Jorge Rodriguez-Guerra, Carlos Calleja, Aron Pujana, Ana Maria Macarulla

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Hydraulic-press commissioning consumes a great amount of man-hours, due to the fact that it takes place several miles away from where it has been designed. This factor became exacerbated due to control designers’ lack of knowledge about which will be the final controller gains before they start working with it. Virtual commissioning has been postulated as an optimal solution to deal with this lack of knowledge. Here, a case study is presented in which a controller is set up against a real-time model based on a hydraulic-press. The press model is designed following manufacturer specifications and it is embedded in a real-time simulator. This methodology ensures that the model achieves similar responses as the real machine that would be placed on the industry. A deterministic communication protocol is in charge of the bidirectional information transmission between the real-time model and the controller. This platform allows the engineer to test and verify the final control responses with exactly the same hardware that is going to be installed in the hydraulic-press, in other words, realize a virtual commissioning of the electro-hydraulic actuator. The Hardware in the Loop (HiL) platform validates in laboratory conditions and harmless for the machine the control algorithms designed, which allows embedding them afterwards in the industrial environment without further modifications.

Keywords: deterministic communication protocol, electro-hydraulic actuator, hardware in the loop, real-time, virtual commissioning

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1581 The Effect of a Reactive Poly (2-Vinyl-2-Oxazoline) Monolayer of Carbon Fiber Surface on the Mechanical Property of Carbon Fiber/Polypropylene Composite Using Maleic Anhydride Grafted Polypropylene

Authors: Teruya Goto, Hokuto Chiba, Tatsuhiro Takahashi

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Carbon fiber reinforced thermoplastic resin using short carbon fiber has been produced by melt mixing and the improvement of mechanical properties has been frequently reported up to now. One of the most frequently reported enhancement has been seen in carbon fiber / polypropylene (PP) composites by adding small amount of maleic anhydride grafted polypropylene (MA-g-PP) into PP matrix. However, the further enhancement of tensile strength and tensile modules has been expected for lightning the composite more. Our present research aims to improve the mechanical property by using a highly reactive monolayer polymer, which can react with both COOH of carbon fiber surface and maleic anhydride of MA-g-PP in the matrix, on carbon fiber for PP/CF composite. It has been known that oxazoline has much higher reactivity with COOH without catalysts, compared with amine group and alcohol OH group. However, oxazoline group has not been used for the interface. To achieve the purpose, poly-2-vinyl-2-oxazoline (Pvozo), having highly reactivity with COOH and maleic anhydride, has been originally synthesized through radical polymerization using 2-vinyl-2-oxazoline as a monomer, resulting in the Mw around 140,000. Monolayer Pvozo chemically reacted on CF was prepared in 1-methoxy-2-propanol solution of Pvozo by heating at 100oC for 3 hours. After this solution treatment, unreacted Pvozo was completely washed out by methanol, resulting the uniform formation of the monolayer Pvozo on CF. Monolayer Pvozo coated CF was melt mixed by with PP and a small amount of MA-g-PP for the preparation of the composite samples using a batch type melt mixer. With performing the tensile strength tests of the composites, the tensile strength of CF/MA-g-PP/PP showed 40% increase, compared to that of CF/PP. While, that of Pvozo coated CF/MA-g-PP/PP exhibited 80% increase, compared to that of CF/PP. To get deeper insight of the dramatic increase, the weight percentage of chemically grafted polymer based on CF was evaluated by dissolving and removing the matrix polymer by xylene using by thermos gravimetric analysis (TGA). The chemically grafted remained polymer was found to be 0.69wt% in CF/PP, 0.98wt% in CF/MA-g-PP/PP, 1.51wt% in Pvozo coated CF/MA-g-PP/PP, suggesting that monolayer Pvozo contributed to the increase of the grafted polymer amount. In addition, the very strong adhesion by Pvozo was confirmed by observing the fractured cross-sectional surface of the composite by scanning electron micrograph (SEM). As a conclusion, the effectiveness of a highly reactive monolayer Pvozo on CF for the enhancement of the mechanical properties of CF/PP composite was demonstrated, which can be interpreted by the clear evidence of the increase of the grafting polymer on CF.

Keywords: CFRTP, interface, oxazoline, polymer graft, mechanical property

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1580 Therapeutic Hypothermia Post Cardiac Arrest

Authors: Tahsien Mohamed Okasha

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We hypothesized that Post cardiac arrest patients with Glasgow coma scale (GCS) score of less than (8) and who will be exposed to therapeutic hypothermia protocol will exhibit improvement in their neurological performance. Purposive sample of 17 patients who were fulfilling the inclusion criteria during one year collected. The study carried out using Quasi-experimental research design. Four Tools used for data collection of this study: Demographic and medical data sheet, Post cardiac arrest health assessment sheet, Bedside Shivering Assessment Scale (BSAS), and Glasgow Pittsburgh cerebral performance category scale (CPC). Result: the mean age was X̅ ± SD = 53 ± 8.122 years, 47.1% were arrested because of cardiac etiology. 35.3% with initial arrest rhythm ventricular tachycardia (VT), 23.5% with ventricular fibrillation (VF), and 29.4% with A-Systole. Favorable neurological outcome was seen among 70.6%. There was significant statistical difference in WBC, Platelets, blood gases value, random blood sugar. Also Initial arrest rhythm, etiology of cardiac arrest, and shivering status were significantly correlated with cerebral performance categories score. therapeutic hypothermia has positive effects on neurological performance among post cardiac arrest patients with GCS score of less than (8). replication of the study on larger probability sample, with randomized control trial design. Further study for suggesting nursing protocol for patients undergoing therapeutic hypothermia.

Keywords: therapeutic hypothermia, neurological performance, after resuscitation from cardiac arrest., resuscitation

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1579 Gingival Tissue Appearance Changes According Hormonal Oscillations at Female Patients

Authors: Ilma Robo, Saimir Heta, Vera Ostreni, Elsaida Agrushi, Eduart Kapaj

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Introduction: Cyclic hormonal fluctuations are known from literature to have a clinically visible effects on gingival tissue reactions, to the diagnosed processes of gingival inflammation. Materials and methods: At a total of 47 female patients, ad-hock presented at the University Clinic, were recorded data on effect of hormonal oscillations at periodontal treatment protocol. Oral examination was performed on soft tissue of gingiva and the oral mucous membrane, always respecting the air-drying procedure and then checking with free eye differences in oral mucosal relief. After the patients were informed about the study protocol, the purpose of the study and the ongoing procedure, verbal consensus was required. Results: The study was conducted in a total of 47 patients, out of which 13 patients were under the gingivitis classification, and 24 patients under the periodontal classification. Patients included in the study are divided by age, cycle week respectively 1,2,3 and 4.The younger age of female patients is more prone to the appearance of gingivitis, which is further aggravated by the effects of sexual hormones and the effect of the controlled or non-regulated fluctuations of the latter. Conclusions: The healing process is more fuel-intensive in the absence of high hormone levels, as they are these pro-inflammatory hormones, both in or near the ho Younger women are more open to volunteering in studies that record individual and study data that may last in time.

Keywords: gingiva, hormonal oscillations, female patients, mucosa, periodontal non-surgical treatment

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1578 A Proposed Treatment Protocol for the Management of Pars Interarticularis Pathology in Children and Adolescents

Authors: Paul Licina, Emma M. Johnston, David Lisle, Mark Young, Chris Brady

Abstract:

Background: Lumbar pars pathology is a common cause of pain in the growing spine. It can be seen in young athletes participating in at-risk sports and can affect sporting performance and long-term health due to its resistance to traditional management. There is a current lack of consensus of classification and treatment for pars injuries. Previous systems used CT to stage pars defects but could not assess early stress reactions. A modified classification is proposed that considers findings on MRI, significantly improving early treatment guidance. The treatment protocol is designed for patients aged 5 to 19 years. Method: Clinical screening identifies patients with a low, medium, or high index of suspicion for lumbar pars injury using patient age, sport participation and pain characteristics. MRI of the at-risk cohort enables augmentation of existing CT-based classification while avoiding ionising radiation. Patients are classified into five categories based on MRI findings. A type 0 lesion (stress reaction) is present when CT is normal and MRI shows high signal change (HSC) in the pars/pedicle on T2 images. A type 1 lesion represents the ‘early defect’ CT classification. The group previously referred to as a 'progressive stage' defect on CT can be split into 2A and 2B categories. 2As have HSC on MRI, whereas 2Bs do not. This distinction is important with regard to healing potential. Type 3 lesions are terminal stage defects on CT, characterised by pseudarthrosis. MRI shows no HSC. Results: Stress reactions (type 0) and acute fractures (1 and 2a) can heal and are treated in a custom-made hard brace for 12 weeks. It is initially worn 23 hours per day. At three weeks, patients commence basic core rehabilitation. At six weeks, in the absence of pain, the brace is removed for sleeping. Exercises are progressed to positions of daily living. Patients with continued pain remain braced 23 hours per day without exercise progression until becoming symptom-free. At nine weeks, patients commence supervised exercises out of the brace for 30 minutes each day. This allows them to re-learn muscular control without rigid support of the brace. At 12 weeks, bracing ceases and MRI is repeated. For patients with near or complete resolution of bony oedema and healing of any cortical defect, rehabilitation is focused on strength and conditioning and sport-specific exercise for the full return to activity. The length of this final stage is approximately nine weeks but depends on factors such as development and level of sports participation. If significant HSC remains on MRI, CT scan is considered to definitively assess cortical defect healing. For these patients, return to high-risk sports is delayed for up to three months. Chronic defects (2b and 3) cannot heal and are not braced, and rehabilitation follows traditional protocols. Conclusion: Appropriate clinical screening and imaging with MRI can identify pars pathology early. In those with potential for healing, we propose hard bracing and appropriate rehabilitation as part of a multidisciplinary management protocol. The validity of this protocol will be tested in future studies.

Keywords: adolescents, MRI classification, pars interticularis, treatment protocol

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1577 Cell Adhesion, Morphology and Cytokine Expression of Synoviocytes Can Be Altered on Different Nano-Topographic Oxidized Silicon Nanosponges

Authors: Hung-Chih Hsu, Pey-Jium Chang, Ching-Hsein Chen, Jer-Liang Andrew Yeh

Abstract:

Osteoarthritis (OA) is a common disorder in rehabilitation clinic. The main characteristics include joint pain, localized tenderness and enlargement, joint effusion, cartilage destruction, loss of adhesion of perichondrium, synovium hyperplasia. Synoviocytes inflammation might be a cause of local tenderness and effusion. Inflammation cytokines might also play an important role in joint pain, cartilage destruction, decrease adhesion of perichondrium to the bone. Treatments of osteoarthritis include non-steroid anti-inflammation drugs (NSAID), glucosamine supplementation, hyaluronic acid, arthroscopic debridement, and total joint replacement. Total joint replacement is commonly used in patients with severe OA who failed respond to pharmacological treatment. However, some patients received surgery had serious adverse events, including instability of the implants due to insufficient adhesion to the adjacent bony tissue or synovial inflammation. We tried to develop ideal nano-topographic oxidized silicon nanosponges by using with various chemicals to produce thickness difference in nanometers in order to study more about the cell-environment interactions in vitro like the alterations of cell adhesion, morphology, extracellular matrix secretions in the pathogenesis of osteoarthritis. Cytokines studies like growth factor, reactive oxygen species, reactive inflammatory materials (Like nitrous oxide and prostaglandin E2), extracellular matrix (ECM) degradation enzymes, and synthesis of collagen will also be observed and discussed. Extracellular and intracellular expression transforming growth factor beta (TGF-β) will be studied by reverse transcription-polymerase chain reaction (RT-PCR). The degradation of ECM will be observed by the bioactivity ratio of matrix metalloproteinase (MMP) and tissue inhibitors of metalloproteinase by ELISA (Enzyme-linked immunosorbent assay). When rabbit synoviocytes were cultured on these nano-topographic structures, they demonstrate better cell adhesion rate, decreased expression of MMP-2,9 and PGE2, and increased expression of TGF-β when cultured in nano-topographic oxidized silicon nanosponges than in the planar oxidized silicon ones. These results show cell behavior, cytokine production can be influenced by physical characteristics from different nano-topographic structures. Our study demonstrates the possibility of manipulating cell behavior in these nano-topographic biomaterials.

Keywords: osteoarthritis, synoviocyte, oxidized silicon surfaces, reactive oxygen species

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1576 Fabrication of Aluminum Nitride Thick Layers by Modified Reactive Plasma Spraying

Authors: Cécile Dufloux, Klaus Böttcher, Heike Oppermann, Jürgen Wollweber

Abstract:

Hexagonal aluminum nitride (AlN) is a promising candidate for several wide band gap semiconductor compound applications such as deep UV light emitting diodes (UVC LED) and fast power transistors (HEMTs). To date, bulk AlN single crystals are still commonly grown from the physical vapor transport (PVT). Single crystalline AlN wafers obtained from this process could offer suitable substrates for a defect-free growth of ultimately active AlGaN layers, however, these wafers still lack from small sizes, limited delivery quantities and high prices so far.Although there is already an increasing interest in the commercial availability of AlN wafers, comparatively cheap Si, SiC or sapphire are still predominantly used as substrate material for the deposition of active AlGaN layers. Nevertheless, due to a lattice mismatch up to 20%, the obtained material shows high defect densities and is, therefore, less suitable for high power devices as described above. Therefore, the use of AlN with specially adapted properties for optical and sensor applications could be promising for mass market products which seem to fulfill fewer requirements. To respond to the demand of suitable AlN target material for the growth of AlGaN layers, we have designed an innovative technology based on reactive plasma spraying. The goal is to produce coarse grained AlN boules with N-terminated columnar structure and high purity. In this process, aluminum is injected into a microwave stimulated nitrogen plasma. AlN, as the product of the reaction between aluminum powder and the plasma activated N2, is deposited onto the target. We used an aluminum filament as the initial material to minimize oxygen contamination during the process. The material was guided through the nitrogen plasma so that the mass turnover was 10g/h. To avoid any impurity contamination by an erosion of the electrodes, an electrode-less discharge was used for the plasma ignition. The pressure was maintained at 600-700 mbar, so the plasma reached a temperature high enough to vaporize the aluminum which subsequently was reacting with the surrounding plasma. The obtained products consist of thick polycrystalline AlN layers with a diameter of 2-3 cm. The crystallinity was determined by X-ray crystallography. The grain structure was systematically investigated by optical and scanning electron microscopy. Furthermore, we performed a Raman spectroscopy to provide evidence of stress in the layers. This paper will discuss the effects of process parameters such as microwave power and deposition geometry (specimen holder, radiation shields, ...) on the topography, crystallinity, and stress distribution of AlN.

Keywords: aluminum nitride, polycrystal, reactive plasma spraying, semiconductor

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1575 Flashsonar or Echolocation Education: Expanding the Function of Hearing and Changing the Meaning of Blindness

Authors: Thomas, Daniel Tajo, Kish

Abstract:

Sight is primarily associated with the function of gathering and processing near and extended spatial information which is largely used to support self-determined interaction with the environment through self-directed movement and navigation. By contrast, hearing is primarily associated with the function of gathering and processing sequential information which may typically be used to support self-determined communication through the self-directed use of music and language. Blindness or the lack of vision is traditionally characterized by a lack of capacity to access spatial information which, in turn, is presumed to result in a lack of capacity for self-determined interaction with the environment due to limitations in self-directed movement and navigation. However, through a specific protocol of FlashSonar education developed by World Access for the Blind, the function of hearing can be expanded in blind people to carry out some of the functions normally associated with sight, that is to access and process near and extended spatial information to construct three-dimensional acoustic images of the environment. This perceptual education protocol results in a significant restoration in blind people of self-determined environmental interaction, movement, and navigational capacities normally attributed to vision - a new way to see. Thus, by expanding the function of hearing to process spatial information to restore self-determined movement, we are not only changing the meaning of blindness, and what it means to be blind, but we are also recasting the meaning of vision and what it is to see.

Keywords: echolocation, changing, sensory, function

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1574 Towards Competence-Based Regulatory Sciences Education in Sub-Saharan Africa: Identification of Competencies

Authors: Abigail Ekeigwe, Bethany McGowan, Loran C. Parker, Stephen Byrn, Kari L. Clase

Abstract:

There are growing calls in the literature to develop and implement competency-based regulatory sciences education (CBRSE) in sub-Saharan Africa to expand and create a pipeline of a competent workforce of regulatory scientists. A defined competence framework is an essential component in developing competency-based education. However, such a competence framework is not available for regulatory scientists in sub-Saharan Africa. The purpose of this research is to identify entry-level competencies for inclusion in a competency framework for regulatory scientists in sub-Saharan Africa as a first step in developing CBRSE. The team systematically reviewed the literature following the PRISMA guidelines for systematic reviews and based on a pre-registered protocol on Open Science Framework (OSF). The protocol has the search strategy and the inclusion and exclusion criteria for publications. All included publications were coded to identify entry-level competencies for regulatory scientists. The team deductively coded the publications included in the study using the 'framework synthesis' model for systematic literature review. The World Health Organization’s conceptualization of competence guided the review and thematic synthesis. Topic and thematic codings were done using NVivo 12™ software. Based on the search strategy in the protocol, 2345 publications were retrieved. Twenty-two (n=22) of the retrieved publications met all the inclusion criteria for the research. Topic and thematic coding of the publications yielded three main domains of competence: knowledge, skills, and enabling behaviors. The knowledge domain has three sub-domains: administrative, regulatory governance/framework, and scientific knowledge. The skills domain has two sub-domains: functional and technical skills. Identification of competencies is the primal step that serves as a bedrock for curriculum development and competency-based education. The competencies identified in this research will help policymakers, educators, institutions, and international development partners design and implement competence-based regulatory science education in sub-Saharan Africa, ultimately leading to access to safe, quality, and effective medical products.

Keywords: competence-based regulatory science education, competencies, systematic review, sub-Saharan Africa

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1573 Effect of Electromagnetic Radiation on Reproductive System of Male Rat

Authors: Rohit Gautam, Kumari Vandana Singh, Jayprakash Nirala, Nina Nancy Murmu, Ramovatar Meena, Paulraj Rajamani

Abstract:

Mobile phones have become a vital part of everyone’s life. Mobile phone and mobile phone towers emit RF-EMR (Radiofrequency Electromagnetic Radiation), which becomes a cause of concern to the general public. The study was designed to evaluate the effect of 3G (RF-EMR) on the reproductive system of male Wistar rats. Adult male Wistar rats were used for the study. Animals were divided into two groups, RF-exposed, and sham-exposed (control). RF-exposed rats were exposed to radio frequency radiation (2100 MHz) for 2 hours/day for 45 days. Emitted power density and specific absorption rate (SAR) values were measured during exposure. At the end of the exposure, testis and epididymis were excised out, and their weights were recorded. Sperm cell count, morphology, viability, and reactive oxygen species (ROS) levels were checked. Lipid peroxidation and sperm mitochondrial activity were measured. Histopathology of testis and ultrastructure analysis of sperm were also checked. Result showed a decrease in organ weight and sperm count with alteration in the sperm morphology in exposed group rats. A significant decrease in sperm viability, membrane integrity, and mitochondrial activity was found. Also, an increase in lipid peroxidation and ROS level were found in exposed group animals as compared to control. It may be concluded that exposure to radiofrequency radiation emits from mobile phones leads to oxidative stress-mediated changes in reproductive parameters.

Keywords: electromagnetic radiation, oxidative stress, reactive oxygen species, sperm

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1572 Economic Community of West African States Court of Justice and the Development of Human Rights Jurisprudence in Africa: A Difficult Take-off with a Bright and Visionary Landing

Authors: Timothy Fwa Yerima

Abstract:

This paper evaluates the development of human rights jurisprudence in Africa by the ECOWAS Court of Justice. It traces that though ECOWAS was not established with the aim of promoting and protecting human rights as the African Court of Human and Peoples’ Rights, no doubt, the 1991 ECOWAS Court Protocol and the 1993 ECOWAS Revised Treaty give the ECOWAS Court its human rights mandate. The paper, however, points out that despite the availability of these two Laws, the ECOWAS Court had difficulty in its human rights mandate, in view of the twin problems of lack of access to the Court by private parties and personal jurisdiction of the Court to entertain cases filed by private parties. The paper considers the 2005 Supplementary Protocol, not only as an effective legal framework in West African Sub-Region that tackles these problems in human rights cases but also a strong foundation upon which the Court has been developing human rights jurisprudence in Africa through the interpretation and application of this Law and other sources of Law of the Court. After a thorough analysis of some principles laid down by the ECOWAS Court so far, the paper observes that human rights jurisprudence in Africa is growing rapidly; depicting that though the ECOWAS Court initially had difficulty in its human rights mandate, today it has a bright and visionary landing. The paper concludes that West African Sub-Region will witness a more effective performance of the ECOWAS Court if some of its challenges are tackled.

Keywords: access, African human rights, ECOWAS court of justice, jurisprudence, personal jurisdiction

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1571 Sensor Network Routing Optimization by Simulating Eurygaster Life in Wheat Farms

Authors: Fariborz Ahmadi, Hamid Salehi, Khosrow Karimi

Abstract:

A sensor network is set of sensor nodes that cooperate together to perform a predefined tasks. The important problem in this network is power consumption. So, in this paper one algorithm based on the eurygaster life is introduced to minimize power consumption by the nodes of these networks. In this method the search space of problem is divided into several partitions and each partition is investigated separately. The evaluation results show that our approach is more efficient in comparison to other evolutionary algorithm like genetic algorithm.

Keywords: evolutionary computation, genetic algorithm, particle swarm optimization, sensor network optimization

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1570 Night Shift Work as an Oxidative Stressor: A Systematic Review

Authors: Madeline Gibson

Abstract:

Night shift workers make up an essential part of the modern workforce. However, night shift workers have higher incidences of late in life diseases and earlier mortality. Night shift workers are exposed to constant light and experience circadian rhythm disruption. Sleep disruption is thought to increase oxidative stress, defined as an imbalance of excess pro-oxidative factors and reactive oxygen species over anti-oxidative activity. Oxidative stress can damage cells, proteins and DNA and can eventually lead to varied chronic diseases such as cancer, diabetes, cardiovascular disease, Alzheimer’s and dementia. This review aimed to understand whether night shift workers were at greater risk of oxidative stress and to contribute to a consensus on this relationship. Twelve studies published in 2001-2019 examining 2,081 workers were included in the review. Studies compared both the impact of working a single shift and in comparisons between those who regularly work night shifts and only day shifts. All studies had evidence to support this relationship across a range of oxidative stress indicators, including increased DNA damage, reduced DNA repair capacity, increased lipid peroxidation, higher levels of reactive oxygen species, and to a lesser extent, a reduction in antioxidant defense. This research supports the theory that melatonin and the sleep-wake cycle mediate the relationship between shift work and oxidative stress. It is concluded that night shift work increases the risk for oxidative stress and, therefore, future disease. Recommendations are made to promote the long-term health of shift workers considering these findings.

Keywords: night shift work, coxidative stress, circadian rhythm, melatonin, disease, circadian rhythm disruption

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1569 Postmodern Navy to Transnational Adaptive Navy: Positive Peace with Borderless Institutional Network

Authors: Serkan Tezgel

Abstract:

Effectively managing threats and power that transcend national boundaries requires a reformulation from the traditional post-modern navy to an adaptive and institutional transnational navy. By analyzing existing soft power concept, post-modern navy, and sea power, this study proposes the transnational navy, founded on the triangle of main attributes of transnational companies, 'Global Competitiveness, Local Responsiveness, Worldwide Learning and Innovation Sharing', a new model which will lead to a positive peace with an institutional network. This transnational model necessitates 'Transnational Navies' to help establish peace with collective and transnational understanding during a transition period 'Reactive Postmodern Navy' has been experiencing. In this regard, it is fairly claimed that a new paradigm shift will revolve around sea power to establish good order at sea with collective and collaborative initiatives and bound to breed new theories and ideas in the forthcoming years. However, there are obstacles to overcome. Postmodern navies, currently shaped by 'Collective Maritime Security' and 'Collective Defense' concepts, can not abandon reactive applications and acts. States deploying postmodern navies to realize their policies on international platforms and seapower structures shaped by the axis of countries’ absolute interests resulted in multipolar alliances and coalitions, but the establishment of the peace. These obstacles can be categorized into three tiers in establishing a unique transnational model navy: Strategic, Organizational and Management challenges. To overcome these obstacles and challenges, postmodern navies should transform into cooperative, collective and independent soft transnational navies with the transnational mentality, global commons, and institutional network. Such an adaptive institution can help the world navigate to a positive peace.

Keywords: postmodern navy, transnational navy, transnational mentality, institutional network

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1568 ZnO Nanoparticles as Photocatalysts: Synthesis, Characterization and Application

Authors: Pachari Chuenta, Suwat Nanan

Abstract:

ZnO nanostructures have been synthesized successfully in high yield via catalyst-free chemical precipitation technique by varying zinc source (either zinc nitrate or zinc acetate) and oxygen source (either oxalic acid or urea) without using any surfactant, organic solvent or capping agent. The ZnO nanostructures were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), UV-vis diffuse reflection spectroscopy (UV-vis DRS), and photoluminescence spectroscopy (PL). The FTIR peak in the range of 450-470 cm-1 corresponded to Zn-O stretching in ZnO structure. The synthesized ZnO samples showed well crystalized hexagonal wurtzite structure. SEM micrographs displayed spherical droplet of about 50-100 nm. The band gap of prepared ZnO was found to be 3.4-3.5 eV. The presence of PL peak at 468 nm was attributed to surface defect state. The photocatalytic activity of ZnO was studied by monitoring the photodegradation of reactive red (RR141) azo dye under ultraviolet (UV) light irradiation. Blank experiment was also separately carried out by irradiating the aqueous solution of the dye in absence of the photocatalyst. The initial concentration of the dye was fixed at 10 mgL-1. About 50 mg of ZnO photocatalyst was dispersed in 200 mL dye solution. The sample was collected at a regular time interval during the irradiation and then was analyzed after centrifugation. The concentration of the dye was determined by monitoring the absorbance at its maximum wavelength (λₘₐₓ) of 544 nm using UV-vis spectroscopic analysis technique. The sources of Zn and O played an important role on photocatalytic performance of the ZnO photocatalyst. ZnO nanoparticles which prepared by zinc acetate and oxalic acid at molar ratio of 1:1 showed high photocatalytic performance of about 97% toward photodegradation of reactive red azo dye (RR141) under UV light irradiation for only 60 min. This work demonstrates the promising potential of ZnO nanomaterials as photocatalysts for environmental remediation.

Keywords: azo dye, chemical precipitation, photocatalytic, ZnO

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1567 Pyrroloquinoline Quinone Enhances the Mitochondrial Function by Increasing Beta-Oxidation and a Balanced Mitochondrial Recycling in Mice Granulosa Cells

Authors: Moustafa Elhamouly, Masayuki Shimada

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The production of competent oocytes is essential for reproductivity in mammals. Maintenance of mitochondrial efficiency is required to supply the ATP necessary for granulosa cell proliferation during the follicular development process. Treatment with Pyrroloquinoline quinone (PQQ) has been reported to increase the number of ovulated oocytes and pups per delivery in mice by maintaining healthy mitochondrial function. This study aimed to elucidate how PQQ maintains mitochondrial function during ovarian follicle growth. To do this, both in vitro and in vivo experiments were performed with granulosa cells from superovulated immature (3-week-old) mice that were pretreated with or without PQQ. The effects of PQQ on beta-oxidation, mitochondrial function, mitophagy, and mitochondrial biogenesis were examined. PQQ increased beta-oxidation-related genes and CPT1 protein content in granulosa cells and this was associated with a decreased phosphorylation of P38 signaling protein. Using the fatty acid oxidation assay on the flux analyzer, PQQ increased the reliance of beta-oxidation on the endogenous fatty acids and was associated with a mild UCP-dependant mitochondrial uncoupling, ATP production, mitophagy, and mitochondrial biogenesis. PQQ also increased the expression of endogenous antioxidant enzymes. Thus, PQQ induced beta-oxidation in growing granulosa cells relying on endogenous fatty acids. And reduced the Reactive oxygen species (ROS) production by inducing a mild mitochondrial uncoupling with keeping high mitochondrial function. Damaged mitochondria were recycled by the induced mitophagy and replaced by the increased mitochondrial biogenesis. Collectively, PQQ may enhance reproductivity by maintaining the efficiency of mitochondria to produce enough ATP required for normal folliculogenesis.

Keywords: granulosa cells, mitochondrial uncoupling, mitophagy, pyrroloquinoline quinone (PQQ), reactive oxygen species (ROS).

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