Search results for: temperature effect
1011 Management and Genetic Characterization of Local Sheep Breeds for Better Productive and Adaptive Traits
Authors: Sonia Bedhiaf-Romdhani
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The sheep (Ovis aries) was domesticated, approximately 11,000 years ago (YBP), in the Fertile Crescent from Asian Mouflon (Ovis Orientalis). The Northern African (NA) sheep is 7,000 years old, represents a remarkable diversity of sheep populations reared under traditional and low input farming systems (LIFS) over millennia. The majority of small ruminants in developing countries are encountered in low input production systems and the resilience of local communities in rural areas is often linked to the wellbeing of small ruminants. Regardless of the rich biodiversity encountered in sheep ecotypes there are four main sheep breeds in the country with 61,6 and 35.4 percents of Barbarine (fat tail breed) and Queue Fine de l’Ouest (thin tail breed), respectively. Phoenicians introduced the Barbarine sheep from the steppes of Central Asia in the Carthaginian period, 3000 years ago. The Queue Fine de l’Ouest is a thin-tailed meat breed heavily concentrated in the Western and the central semi-arid regions. The Noire de Thibar breed, involving mutton-fine wool producing animals, has been on the verge of extinction, it’s a composite black coated sheep breed found in the northern sub-humid region because of its higher nutritional requirements and non-tolerance of the prevailing harsher condition. The D'Man breed, originated from Morocco, is mainly located in the southern oases of the extreme arid ecosystem. A genetic investigation of Tunisian sheep breeds using a genome-wide scan of approximately 50,000 SNPs was performed. Genetic analysis of relationship between breeds highlighted the genetic differentiation of Noire de Thibar breed from the other local breeds, reflecting the effect of past events of introgression of European gene pool. The Queue Fine de l’Ouest breed showed a genetic heterogeneity and was close to Barbarine. The D'Man breed shared a considerable gene flow with the thin-tailed Queue Fine de l'Ouest breed. Native small ruminants breeds, are capable to be efficiently productive if essential ingredients and coherent breeding schemes are implemented and followed. Assessing the status of genetic variability of native sheep breeds could provide important clues for research and policy makers to devise better strategies for the conservation and management of genetic resources.Keywords: sheep, farming systems, diversity, SNPs.
Procedia PDF Downloads 1471010 Interlayer-Mechanical Working: Effective Strategy to Mitigate Solidification Cracking in Wire-Arc Additive Manufacturing (WAAM) of Fe-based Shape Memory Alloy
Authors: Soumyajit Koley, Kuladeep Rajamudili, Supriyo Ganguly
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In recent years, iron-based shape-memory alloys have been emerging as an inexpensive alternative to costly Ni-Ti alloy and thus considered suitable for many different applications in civil structures. Fe-17Mn-10Cr-5Si-4Ni-0.5V-0.5C alloy contains 37 wt.% of total solute elements. Such complex multi-component metallurgical system often leads to severe solute segregation and solidification cracking. Wire-arc additive manufacturing (WAAM) of Fe-17Mn-10Cr-5Si-4Ni-0.5V-0.5C alloy was attempted using a cold-wire fed plasma arc torch attached to a 6-axis robot. Self-standing walls were manufactured. However, multiple vertical cracks were observed after deposition of around 15 layers. Microstructural characterization revealed open surfaces of dendrites inside the crack, confirming these cracks as solidification cracks. Machine hammer peening (MHP) process was adopted on each layer to cold work the newly deposited alloy. Effect of MHP traverse speed were varied systematically to attain a window of operation where cracking was completely stopped. Microstructural and textural analysis were carried out further to correlate the peening process to microstructure.MHP helped in many ways. Firstly, a compressive residual stress was induced on each layer which countered the tensile residual stress evolved from solidification process; thus, reducing net tensile stress on the wall along its length. Secondly, significant local plastic deformation from MHP followed by the thermal cycle induced by deposition of next layer resulted into a recovered and recrystallized equiaxed microstructure instead of long columnar grains along the vertical direction. This microstructural change increased the total crack propagation length and thus, the overall toughness. Thirdly, the inter-layer peening significantly reduced the strong cubic {001} crystallographic texture formed along the build direction. Cubic {001} texture promotes easy separation of planes and easy crack propagation. Thus reduction of cubic texture alleviates the chance of cracking.Keywords: Iron-based shape-memory alloy, wire-arc additive manufacturing, solidification cracking, inter-layer cold working, machine hammer peening
Procedia PDF Downloads 721009 Glutamine Supplementation and Resistance Traning on Anthropometric Indices, Immunoglobulins, and Cortisol Levels
Authors: Alireza Barari, Saeed Shirali, Ahmad Abdi
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Introduction: Exercise has contradictory effects on the immune system. Glutamine supplementation may increase the resistance of the immune system in athletes. The Glutamine is one of the most recognized immune nutrients that as a fuel source, substrate in the synthesis of nucleotides and amino acids and is also known to be part of the antioxidant defense. Several studies have shown that improving glutamine levels in plasma and tissues can have beneficial effects on the function of immune cells such as lymphocytes and neutrophils. This study aimed to investigate the effects of resistance training and training combined with glutamine supplementation to improve the levels of cortisol and immunoglobulin in untrained young men. The research shows that physical training can increase the cytokines in the athlete’s body of course; glutamine can counteract the negative effects of resistance training on immune function and stability of the mast cell membrane. Materials and methods: This semi-experimental study was conducted on 30 male non-athletes. They were randomly divided into three groups: control (no exercise), resistance training, resistance training and glutamine supplementation, respectively. Resistance training for 4 weeks and glutamine supplementation in 0.3 gr/kg/day after practice was applied. The resistance-training program consisted of eight exercises (leg press, lat pull, chest press, squat, seatedrow, abdominal crunch, shoulder press, biceps curl and triceps press down) four times per week. Participants performed 3 sets of 10 repetitions at 60–75% 1-RM. Anthropometry indexes (weight, body mass index, and body fat percentage), oxygen uptake (VO2max) Maximal, cortisol levels of immunoglobulins (IgA, IgG, IgM) were evaluated Pre- and post-test. Results: Results showed four week resistance training with and without glutamine cause significant increase in body weight, BMI and significantly decreased (P < 0/001) in BF. Vo2max also increased in both groups of exercise (P < 0/05) and exercise with glutamine (P < 0/001), such as in both groups significant reduction in IgG (P < 0/05) was observed. But no significant difference observed in levels of cortisol, IgA, IgM in any of the groups. No significant change observed in either parameter in the control group. No significant difference observed between the groups. Discussion: The alterations in the hormonal and immunological parameters can be used in order to assess the effect overload on the body, whether acute or chronically. The plasmatic concentration of glutamine has been associated to the functionality of the immunological system in individuals sub-mitted to intense physical training. resistance training has destructive effects on the immune system and glutamine supplementation cannot neutralize the damaging effects of power exercise on the immune system.Keywords: glutamine, resistance traning, immuglobulins, cortisol
Procedia PDF Downloads 4791008 The Role of EDTA and EDDS in Reducing Metal Toxicity for Aquaculture Shellfish Perna canaliculus
Authors: Daniel R. McDougall, Martin D. de Jonge, Gordon M. Miskelly, Duncan J. McGillivray, Andrew G. Jeffs
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The chelating agent ethylenediaminetetraacetic acid (EDTA) is commonly added as a cure-all to seawater in aquaculture hatcheries around the world to reduce heavy metal toxicity, significantly improve the survival of larval shellfish, and to therefore improve the overall production efficiency of the aquaculture industry. However, EDTA is not a biodegradable chemical and is considered to be a persistent organic pollutant, which will accumulate in the environment over time. This makes the use of EDTA unsustainable environmentally, and therefore alternatives should be considered. Ethylenediaminedisuccinic acid (EDDS) is a biodegradable alternative to EDTA with very similar metal chelation properties. This study investigates the effect of EDTA and EDDS at two different concentrations, on metal concentrations found within developing New Zealand green-lipped mussel (Perna canaliculus) larvae. P. canaliculus is New Zealand’s main shellfish aquaculture species, providing a major export for New Zealand’s economy, with excellent potential for increased production in the near future. It is well known that the early stages of bivalve development are the most vulnerable to metal toxicity and P. canaliculus is no exception. The commercially used concentration (12 µmol L⁻¹) of EDTA added to P. canaliculus larval rearing tanks often increases the yield of D-larvae by over 80%. This concentration of EDTA and EDDS will be tested in this study, along with a lower concentration (3 µmol L⁻¹). After 48 hours of larval development, the D-larvae will be analyzed for heavy metal content with Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and heavy metal distribution with synchrotron X-ray Fluorescence Microscopy (XFM). In this study, we found that EDDS also improves the yield of P. canaliculus larvae and could be a viable alternative to EDTA in aquaculture. Furthermore, results suggest a higher concentration of chelating agent is more effective for improving the yield of developing P. canaliculus larvae. Metals with significant differences in concentration with the addition of EDTA were Cr, Cu, Zn, Cd and Pb (P < 0.05). We observed for the first time to the author’s best knowledge, metal distribution within 100 µm P. canaliculus D-larvae using synchrotron XFM and found changes in the distribution of metals with the addition of EDTA. XFM also has the potential to provide information about the chemical state of the metals within mussel larvae. This research provides greater insight into the reasons for the effectiveness of adding the chelating agent to aquaculture culture water, and a more environmentally conscious alternative to the currently used EDTA, which could be extremely valuable for the aquaculture industry.Keywords: EDDS, EDTA, heavy metals, P. canaliculus, toxicity, water treatment
Procedia PDF Downloads 2311007 Study of Phase Separation Behavior in Flexible Polyurethane Foam
Authors: El Hatka Hicham, Hafidi Youssef, Saghiri Khalid, Ittobane Najim
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Flexible polyurethane foam (FPUF) is a low-density cellular material generally used as a cushioning material in many applications such as furniture, bedding, packaging, etc. It is commercially produced during a continuous process, where a reactive mixture of foam chemicals is poured onto a moving conveyor. FPUFs are produced by the catalytic balancing of two reactions involved, the blowing reaction (isocyanate-water) and the gelation reaction (isocyanate-polyol). The microstructure of FPUF is generally composed of soft phases (polyol phases) and rigid domains that separate into two domains of different sizes: the rigid polyurea microdomains and the macrodomains (larger aggregates). The morphological features of FPUF are strongly influenced by the phase separation morphology that plays a key role in determining the global FPUF properties. This phase-separated morphology results from a thermodynamic incompatibility between soft segments derived from aliphatic polyether and hard segments derived from the commonly used aromatic isocyanate. In order to improve the properties of FPUF against the different stresses faced by this material during its use, we report in this work a study of the phase separation phenomenon in FPUF that has been examined using SAXS WAXS and FTIR. Indeed, we have studied with these techniques the effect of water, isocyanates, and alkaline chlorides on the phase separation behavior. SAXS was used to study the morphology of the microphase separated, WAXS to examine the nature of the hard segment packing, and FTIR to investigate the hydrogen bonding characteristics of the materials studied. The prepared foams were shown to have different levels of urea phase connectivity; the increase in water content in the FPUF formulation leads to an increase in the amount of urea formed and consequently the increase of the size of urea aggregates formed. Alkali chlorides (NaCl, KCl, and LiCl) incorporated into FPUF formulations show that is the ability to prevent hydrogen bond formation and subsequently alter the rigid domains. FPUFs prepared by different isocyanate structures showed that urea aggregates are difficult to be formed in foams prepared by asymmetric diisocyanate, while are more easily formed in foams prepared by symmetric and aliphatic diisocyanate.Keywords: flexible polyurethane foam, hard segments, phase separation, soft segments
Procedia PDF Downloads 1641006 Coupling of Microfluidic Droplet Systems with ESI-MS Detection for Reaction Optimization
Authors: Julia R. Beulig, Stefan Ohla, Detlev Belder
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In contrast to off-line analytical methods, lab-on-a-chip technology delivers direct information about the observed reaction. Therefore, microfluidic devices make an important scientific contribution, e.g. in the field of synthetic chemistry. Herein, the rapid generation of analytical data can be applied for the optimization of chemical reactions. These microfluidic devices enable a fast change of reaction conditions as well as a resource saving method of operation. In the presented work, we focus on the investigation of multiphase regimes, more specifically on a biphasic microfluidic droplet systems. Here, every single droplet is a reaction container with customized conditions. The biggest challenge is the rapid qualitative and quantitative readout of information as most detection techniques for droplet systems are non-specific, time-consuming or too slow. An exception is the electrospray mass spectrometry (ESI-MS). The combination of a reaction screening platform with a rapid and specific detection method is an important step in droplet-based microfluidics. In this work, we present a novel approach for synthesis optimization on the nanoliter scale with direct ESI-MS detection. The development of a droplet-based microfluidic device, which enables the modification of different parameters while simultaneously monitoring the effect on the reaction within a single run, is shown. By common soft- and photolithographic techniques a polydimethylsiloxane (PDMS) microfluidic chip with different functionalities is developed. As an interface for the MS detection, we use a steel capillary for ESI and improve the spray stability with a Teflon siphon tubing, which is inserted underneath the steel capillary. By optimizing the flow rates, it is possible to screen parameters of various reactions, this is exemplarity shown by a Domino Knoevenagel Hetero-Diels-Alder reaction. Different starting materials, catalyst concentrations and solvent compositions are investigated. Due to the high repetition rate of the droplet production, each set of reaction condition is examined hundreds of times. As a result, of the investigation, we receive possible reagents, the ideal water-methanol ratio of the solvent and the most effective catalyst concentration. The developed system can help to determine important information about the optimal parameters of a reaction within a short time. With this novel tool, we make an important step on the field of combining droplet-based microfluidics with organic reaction screening.Keywords: droplet, mass spectrometry, microfluidics, organic reaction, screening
Procedia PDF Downloads 3011005 The Evolution of Moral Politics: Analysis on Moral Foundations of Korean Parties
Authors: Changdong Oh
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With the arrival of post-industrial society, social scientists have been giving attention to issues of which factors shape cleavage of political parties. Especially, there is a heated controversy over whether and how social and cultural values influence the identities of parties and voting behavior. Drawing from Moral Foundations Theory (MFT), which approached similar issues by considering the effect of five moral foundations on political decision-making of people, this study investigates the role of moral rhetoric in the evolution of Korean political parties. Researcher collected official announcements released by the major two parties (Democratic Party of Korea, Saenuri Party) from 2007 to 2016, and analyzed the data by using Word2Vec algorithm and Moral Foundations Dictionary. Five moral decision modules of MFT, composed of care, fairness (individualistic morality), loyalty, authority and sanctity (group-based, Durkheimian morality), can be represented in vector spaces consisted of party announcements data. By comparing the party vector and the five morality vectors, researcher can see how the political parties have actively used each of the five moral foundations to express themselves and the opposition. Results report that the conservative party tends to actively draw on collective morality such as loyalty, authority, purity to differentiate itself. Notably, such moral differentiation strategy is prevalent when they criticize an opposition party. In contrast, the liberal party tends to concern with individualistic morality such as fairness. This result indicates that moral cleavage does exist between parties in South Korea. Furthermore, individualistic moral gaps of the two political parties are eased over time, which seems to be due to the discussion of economic democratization of conservative party that emerged after 2012, but the community-related moral gaps widened. These results imply that past political cleavages related to economic interests are diminishing and replaced by cultural and social values associated with communitarian morality. However, since the conservative party’s differentiation strategy is largely related to negative campaigns, it is doubtful whether such moral differentiation among political parties can contribute to the long-term party identification of the voters, thus further research is needed to determine it is sustainable. Despite the limitations, this study makes it possible to track and identify the moral changes of party system through automated text analysis. More generally, this study could contribute to the analysis of various texts associated with the moral foundation and finding a distributed representation of moral, ethical values.Keywords: moral foundations theory, moral politics, party system, Word2Vec
Procedia PDF Downloads 3621004 Escalation of Commitment and Turnover in Top Management Teams
Authors: Dmitriy V. Chulkov
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Escalation of commitment is defined as continuation of a project after receiving negative information about it. While literature in management and psychology identified various factors contributing to escalation behavior, this phenomenon has received little analysis in economics, potentially due to the apparent irrationality of escalation. In this study, we present an economic model of escalation with asymmetric information in a principal-agent setup where the agents are responsible for a project selection decision and discover the outcome of the project before the principal. Our theoretical model complements the existing literature on several accounts. First, we link the incentive to escalate commitment to a project with the turnover decision by the manager. When a manager learns the outcome of the project and stops it that reveals that a mistake was made. There is an incentive to continue failing projects and avoid admitting the mistake. This incentive is enhanced when the agent may voluntarily resign from the firm before the outcome of the failing project is revealed, and thus not bear the full extent of reputation damage due to project failure. As long as some successful managers leave the firm for extraneous reasons, outside firms find it difficult to link failing projects with certainty to managers that left a firm. Second, we demonstrate that non-CEO managers have reputation concerns separate from those of the CEO, and thus may escalate commitment to projects they oversee, when such escalation can attenuate damage to reputation from impending project failure. Such incentive for escalation will be present for non-CEO managers if the CEO delegates responsibility for a project to a non-CEO executive. If reputation matters for promotion to the CEO, the incentive for a rising executive to escalate in order to protect reputation is distinct from that of a CEO. Third, our theoretical model is supported by empirical analysis of changes in the firm’s operations measured by the presence of discontinued operations at the time of turnover among the top four members of the top management team. Discontinued operations are indicative of termination of failing projects at a firm. The empirical results demonstrate that in a large dataset of over three thousand publicly traded U.S. firms for a period from 1993 to 2014 turnover by top executives significantly increases the likelihood that the firm discontinues operations. Furthermore, the type of turnover matters as this effect is strongest when at least one non-CEO member of the top management team leaves the firm and when the CEO departure is due to a voluntary resignation and not to a retirement or illness. Empirical results are consistent with the predictions of the theoretical model and suggest that escalation of commitment is primarily observed in decisions by non-CEO members of the top management team.Keywords: discontinued operations, escalation of commitment, executive turnover, top management teams
Procedia PDF Downloads 3651003 Spatial Pattern and Predictors of Malaria in Ethiopia: Application of Auto Logistics Spatial Regression
Authors: Melkamu A. Zeru, Yamral M. Warkaw, Aweke A. Mitku, Muluwerk Ayele
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Introduction: Malaria is a severe health threat in the World, mainly in Africa. It is the major cause of health problems in which the risk of morbidity and mortality associated with malaria cases are characterized by spatial variations across the county. This study aimed to investigate the spatial patterns and predictors of malaria distribution in Ethiopia. Methods: A weighted sample of 15,239 individuals with rapid diagnosis tests was obtained from the Central Statistical Agency and Ethiopia malaria indicator survey of 2015. Global Moran's I and Moran scatter plots were used in determining the distribution of malaria cases, whereas the local Moran's I statistic was used in identifying exposed areas. In data manipulation, machine learning was used for variable reduction and statistical software R, Stata, and Python were used for data management and analysis. The auto logistics spatial binary regression model was used to investigate the predictors of malaria. Results: The final auto logistics regression model reported that male clients had a positive significant effect on malaria cases as compared to female clients [AOR=2.401, 95 % CI: (2.125 - 2.713)]. The distribution of malaria across the regions was different. The highest incidence of malaria was found in Gambela [AOR=52.55, 95%CI: (40.54-68.12)] followed by Beneshangul [AOR=34.95, 95%CI: (27.159 - 44.963)]. Similarly, individuals in Amhara [AOR=0.243, 95% CI:(0.1950.303],Oromiya[AOR=0.197,95%CI:(0.1580.244)],DireDawa[AOR=0.064,95%CI(0.049-0.082)],AddisAbaba[AOR=0.057,95%CI:(0.044-0.075)], Somali[AOR=0.077,95%CI:(0.059-0.097)], SNNPR[OR=0.329, 95%CI: (0.261- 0.413)] and Harari [AOR=0.256, 95%CI:(0.201 - 0.325)] were less likely to had low incidence of malaria as compared with Tigray. Furthermore, for a one-meter increase in altitude, the odds of a positive rapid diagnostic test (RDT) decrease by 1.6% [AOR = 0.984, 95% CI :( 0.984 - 0.984)]. The use of a shared toilet facility was found as a protective factor for malaria in Ethiopia [AOR=1.671, 95% CI: (1.504 - 1.854)]. The spatial autocorrelation variable changes the constant from AOR = 0.471 for logistic regression to AOR = 0.164 for auto logistics regression. Conclusions: This study found that the incidence of malaria in Ethiopia had a spatial pattern that is associated with socio-economic, demographic, and geographic risk factors. Spatial clustering of malaria cases had occurred in all regions, and the risk of clustering was different across the regions. The risk of malaria was found to be higher for those who live in soil floor-type houses as compared to those who live in cement or ceramics floor type. Similarly, households with thatched, metal and thin, and other roof-type houses have a higher risk of malaria than ceramic tiles roof houses. Moreover, using a protected anti-mosquito net reduced the risk of malaria incidence.Keywords: malaria, Ethiopia, auto logistics, spatial model, spatial clustering
Procedia PDF Downloads 341002 Human Resource Management Practices and Employee Retention in Public Higher Learning Institutions in the Maldives
Authors: Shaheeb Abdul Azeez, Siong-Choy Chong
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Background: Talent retention is increasingly becoming a major challenge for many industries due to the high turnover rate. Public higher learning institutions in the Maldives have a similar situation with the turnover of their employees'. This paper is to identify whether Human Resource Management (HRM) practices have any impact on employee retention in public higher learning institutions in the Maldives. Purpose: This paper aims to identify the influence of HRM practices on employee retention in public higher learning institutions in the Maldives. A total of 15 variables used in this study; 11 HRM practices as independent variables (leadership, rewards, salary, employee participation, compensation, training and development, career development, recognition, appraisal system and supervisor support); job satisfaction and motivation as mediating variables; demographic profile as moderating variable and employee retention as dependent variable. Design/Methodology/Approach: A structured self-administered questionnaire was used for data collection. A total of 300 respondents were selected as the study sample, representing the academic and administrative from public higher learning institutions using a stratified random sampling method. AMOS was used to test the hypotheses constructed. Findings: The results suggest that there is no direct effect between the independent variable and dependent variable. Also, the study concludes that no moderate effects of demographic profile between independent and dependent variables. However, the mediating effects of job satisfaction and motivation in the relationship between HRM practices and employee retention were significant. Salary had a significant influence on job satisfaction, whilst both compensation and recognition have significant influence on motivation. Job satisfaction and motivation were also found to significantly influence employee retention. Research Limitations: The study consists of many variables more time consuming for the respondents to answer the questionnaire. The study is focussed only on public higher learning institutions in the Maldives due to no participation from the private sector higher learning institutions. Therefore, the researcher is unable to identify the actual situation of the higher learning industry in the Maldives. Originality/Value: To our best knowledge, no study has been conducted using the same framework throughout the world. This study is the initial study conducted in the Maldives in this study area and can be used as a baseline for future researches. But there are few types of research conducted on the same subject throughout the world. Some of them concluded with positive findings while others with negative findings. Also, they have used 4 to 7 HRM practices as their study framework.Keywords: human resource management practices, employee retention, motivation, job satisfaction
Procedia PDF Downloads 1561001 Beware the Trolldom: Speculative Interests and Policy Implications behind the Circulation of Damage Claims
Authors: Antonio Davola
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Moving from the evaluations operated by Richard Posner in his judgment on the case Carhart v. Halaska, the paper seeks to analyse the so-called ‘litigation troll’ phenomenon and the development of a damage claims market, i.e. a market in which the right to propose claims is voluntary exchangeable for money and can be asserted by private buyers. The aim of our study is to assess whether the implementation of a ‘damage claims market’ might represent a resource for victims or if, on the contrary, it might operate solely as a speculation tool for private investors. The analysis will move from the US experience, and will then focus on the EU framework. Firstly, the paper will analyse the relation between the litigation troll phenomenon and the patent troll activity: even though these activities are considered similar by Posner, a comparative study shows how these practices significantly differ in their impact on the market and on consumer protection, even moving from similar economic perspectives. The second part of the paper will focus on the main specific concerns related to the litigation trolling activity. The main issues that will be addressed are the risk that the circulation of damage claims might spur non-meritorious litigation and the implications of the misalignment between the victim of a tort and the actual plaintiff in court arising from the sale of a claim. In its third part, the paper will then focus on the opportunities and benefits that the introduction and regulation of a claims market might imply both for potential claims sellers and buyers, in order to ultimately assess whether such a solution might actually increase individual’s legal empowerment. Through the damage claims market compensation would be granted more quickly and easily to consumers who had suffered harm: tort victims would, in fact, be compensated instantly upon the sale of their claims without any burden of proof. On the other hand, claim-buyers would profit from the gap between the amount that a consumer would accept for an immediate refund and the compensation awarded in court. In the fourth part of the paper, the analysis will focus on the legal legitimacy of the litigation trolling activity in the US and the EU framework. Even though there is no express provision that forbids the sale of the right to pursue a claim in court - or that deems such a right to be non-transferable – procedural laws of single States (especially in the EU panorama) must be taken into account in evaluating this aspect. The fifth and final part of the paper will summarize the various data collected to suggest an evaluation on if, and through which normative solutions, the litigation trolling might comport benefits for competition and which would be its overall effect over consumer’s protection.Keywords: competition, claims, consumer's protection, litigation
Procedia PDF Downloads 2311000 Effect of Wheat Germ Agglutinin- and Lactoferrin-Grafted Catanionic Solid Lipid Nanoparticles on Targeting Delivery of Etoposide to Glioblastoma Multiforme
Authors: Yung-Chih Kuo, I-Hsin Wang
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Catanionic solid lipid nanoparticles (CASLNs) with surface wheat germ agglutinin (WGA) and lactoferrin (Lf) were formulated for entrapping and releasing etoposide (ETP), crossing the blood–brain barrier (BBB), and inhibiting the growth of glioblastoma multiforme (GBM). Microemulsified ETP-CASLNs were modified with WGA and Lf for permeating a cultured monolayer of human brain-microvascular endothelial cells (HBMECs) regulated by human astrocytes and for treating malignant U87MG cells. Experimental evidence revealed that an increase in the concentration of catanionic surfactant from 5 μM to 7.5 μM reduced the particle size. When the concentration of catanionic surfactant increased from 7.5 μM to 12.5 μM, the particle size increased, yielding a minimal diameter of WGA-Lf-ETP-CASLNs at 7.5 μM of catanionic surfactant. An increase in the weight percentage of BW from 25% to 75% enlarged WGA-Lf-ETP-CASLNs. In addition, an increase in the concentration of catanionic surfactant from 5 to 15 μM increased the absolute value of zeta potential of WGA-Lf-ETP-CASLNs. It was intriguing that the increment of the charge as a function of the concentration of catanionic surfactant was approximately linear. WGA-Lf-ETP-CASLNs revealed an integral structure with smooth particle contour, displayed a lighter exterior layer of catanionic surfactant, WGA, and Lf and showed a rigid interior region of solid lipids. A variation in the concentration of catanionic surfactant between 5 μM and 15 μM yielded a maximal encapsulation efficiency of ETP ata 7.5 μM of catanionic surfactant. An increase in the concentration of Lf/WGA decreased the grafting efficiency of Lf/WGA. Also, an increase in the weight percentage of ETP decreased its encapsulation efficiency. Moreover, the release rate of ETP from WGA-Lf-ETP-CASLNs reduced with increasing concentration of catanionic surfactant, and WGA-Lf-ETP-CASLNs at 12.5 μM of catanionic surfactant exhibited a feature of sustained release. The order in the viability of HBMECs was ETP-CASLNs ≅ Lf-ETP-CASLNs ≅ WGA-Lf-ETP-CASLNs > ETP. The variation in the transendothelial electrical resistance (TEER) and permeability of propidium iodide (PI) was negligible when the concentration of Lf increased. Furthermore, an increase in the concentration of WGA from 0.2 to 0.6 mg/mL insignificantly altered the TEER and permeability of PI. When the concentration of Lf increased from 2.5 to 7.5 μg/mL and the concentration of WGA increased from 2.5 to 5 μg/mL, the enhancement in the permeability of ETP was minor. However, 10 μg/mL of Lf promoted the permeability of ETP using Lf-ETP-CASLNs, and 5 and 10 μg/mL of WGA could considerably improve the permeability of ETP using WGA-Lf-ETP-CASLNs. The order in the efficacy of inhibiting U87MG cells was WGA-Lf-ETP-CASLNs > Lf-ETP-CASLNs > ETP-CASLNs > ETP. As a result, WGA-Lf-ETP-CASLNs reduced the TEER, enhanced the permeability of PI, induced a minor cytotoxicity to HBMECs, increased the permeability of ETP across the BBB, and improved the antiproliferative efficacy of U87MG cells. The grafting of WGA and Lf is crucial to control the medicinal property of ETP-CASLNs and WGA-Lf-ETP-CASLNs can be promising colloidal carriers in GBM management.Keywords: catanionic solid lipid nanoparticle, etoposide, glioblastoma multiforme, lactoferrin, wheat germ agglutinin
Procedia PDF Downloads 237999 Evaluation of the Anti Ulcer Activity of Ethyl Acetate Fraction of Methanol Leaf Extract of Clerodendrum Capitatum
Authors: M. N. Ofokansi, Onyemelukwe Chisom, Amauche Chukwuemeka, Ezema Onyinye
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The leaves of Clerodendrumcapitatum(Lamiaceae) is mostly used in the treatment of gastric ulcer in Nigerian folk medicine. The aim of this study was to evaluate the antiulcer activity of its crude methanol leaf extract and its ethyl acetate fraction in white albino rats. The effect of crude methanol leaf extract and its ethyl acetate fraction(250mg/kg, 500mg/kg) was evaluated using an absolute ethanol induced ulcer model. Crude methanol leaf extract and the ethyl acetate fraction was treated with distilled water and 6% Tween 80, respectively. crude methanol leaf extract was further investigated using a pylorus ligation induced ulcer model. Omeprazole was used as the standard treatment. Four groups of five albino rats of either sex were used. Parameters such as mean ulcer index and percentage ulcer protection were assessed in the ethanol-induced ulcer model, while the gastric volume, pH, and total acidity were assessed in the pyloric ligation induced ulcer model. Crude methanol leaf extract of Clerodendrumcapitatum(500mg/kg) showed a very highly significant reduction in mean ulcer index(p<0.001) in the absolute ethanol-induced model. ethyl acetate fraction of crude methanol leaf extract of Clerodendrumcapitatum(250mg/kg,500mg/kg) showed a very highly significant dose-dependent reduction in mean ulcer indices (p<0.001) in the absolute ethanol-induced model. The mean ulcer indices (1.6,2.2) with dose concentration (250mg/kg, 500mg/kg) of ethyl acetate fraction increased with ulcer protection (82.85%,76.42%) respectively when compared to the control group in the absolute ethanol-induced ulcer model. Crude methanol leaf extract of Clerodendrumcapitatum(250mg/kg, 500mg/kg) treated animals showed a highly significant dose-dependent reduction in mean ulcer index(p<0.01) with an increase in ulcer protection (56.77%,63.22%) respectively in pyloric ligated induced, ulcer model. Gastric parameters such as volume of gastric juice, pH, and total acidity were of no significance in the different doses of the crude methanol leaf extract when compared to the control group. The phytochemical investigation showed that the crude methanol leaf extracts Possess Saponins and Flavonoids while its ethyl acetate fraction possess only Flavonoids. The results of the study indicate that the crude methanol leaf extract and its ethyl acetate fraction is effective and has gastro protective and ulcer healing capacity. Ethyl acetate fraction is more potent than crude methanol leaf extract against ethanol-induced This result provides scientific evidence as a validation for its folkloric use in the treatment of gastric ulcer.Keywords: gastroprotective, herbal medicine, anti-ulcer, pharmacology
Procedia PDF Downloads 162998 African Pattern Trends in Contemporary Textile and Fashion Design: Exploratory Study in African Sources and Technology in Fashion, Art, and Textiles
Authors: Leslie Nobler
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African fabrics based specifically on the Dutch Wax Print, or Ankara, popularized during Africa's colonial era, have had an enormous impact on western fashion (especially in the US and UK), in the last half-decade. The trend has had an effect on the world of visual arts as well, which circuitously, also heavily impacts fashion design. In fashion, and notably in celebrity apparel choices, this is in part due to ‘identity’ and taking pride in one's African roots; in the visual arts, artists such as Yinka Shonibare and Njideka Akunyili Crosby are making statements about identity politics, colonialism up through post-colonialism, and racism. The ‘global village’ brought on by the internet has driven this proliferation, as have improvements in the printing technology with which the Ankara print is made, combining wax-resist with roller printing. The newest patterns can now be designed authentically in western African and easily sent electronically to Europe for printing. Examples of Ankara's new reach across the Atlantic abound. They have taken several paths, which the paper will detail. Briefly, the first is its greater utilization in the fashion world, from authentic textile shops in African American neighborhoods to copied (knocked-off) low-end reproductions in discount chains. Secondly, we are seeing far more uses of these textiles/patterns in important works of fine arts from major museums, in Philadelphia to Palm Beach to the Mass MOCA (in the US), all the way to the Israel Museum in Jerusalem, and everywhere in between. And lastly, but quite significantly, we see this trend throughout social media thanks to Instagram, Pinterest and celebrity photos –even at the recent royal wedding. What shall sustain this major new design direction is that Ankara changes with and adapts to the times. Some of it is now printed in West Africa, often in the Nigeria area. And some may be designed in Europe or even at knock-off apparel studios in NY or Asia. But it stays utterly relevant because the motifs are based on objects and scenes in everyday life. In my design studio and university design classes, this idea is first and foremost, from our big spiritual eye motifs to drawings of our art supplies to the ‘politically-loaded’ chain patterns. This first-hand creativity experience becomes part of the research of this paper, along with historic and contemporary sources of inquiry, both through a literature/image search and anecdotal experience into what is behind this exciting and surprising trend.Keywords: African wax print, Ankara, identity (politics), textile design, surface design
Procedia PDF Downloads 133997 In vitro Effects of Porcine Follicular Fluid Proteins on Cell Culture Growth in Luteal Phase Porcine Oviductal Epithelial Cells
Authors: Mayuva Youngsabanant, Chanikarn Srinark, Supanyika Sengsai, Soratorn Kerdkriangkrai, Nongnuch Gumlungpat, Mayuree Pumipaiboon
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The follicular fluid proteins of healthy medium size follicles (4-6 mm in diameters) and large size follicles (7-8 mm in diameter) of large white pig ovaries were collected by using sterile technique. They were used for testing the effect on primary in vitro cell culture growth of porcine oviductal epithelial cells (pOEC). Porcine oviductal epithelial cells of luteal phase was culture in M199 and added with 10% fetal calf serum 2.2 mg/mL, NaHCO₃, 0.25 mM pyruvate, 15 µg/mL and 50 µg/mL, gentamycin sulfate at high humidified atmosphere with 5% CO₂ in 95% air atmosphere at 37°C for 96 h before testing. The optimized concentration of pFF of two follicle sizes (at concentration of 2, 4, 20, 40, 200, 400, 500, and 600 µg proteins) in culture medium was observed for 24 h using MTT assay. Results were analyzed with a one-way ANOVA in SPSS statistic. Moreover, pOEC was also studied in morphological characteristic on long-term culture. The results of long-term study revealed that pOEC showed 70-80 percentage of healthy morphology on epithelial-like character and contained 30 percentage of an elongated shape (fibroblast-like morphology) at 4 weeks of culture time. MTT assay reviewed an increase in the percentage of viability of pOEC in 2 treated of follicular fluid groups. Two treatment concentration groups were higher than control group (p < 0.05) but not in positive control group. Interestingly, at 200 µg protein of 2 treated follicular fluid groups were reached the highest cell viability which is higher than a positive control and it is significantly different form control group (P < 0.05). These cells are developed and had fibroblast elongate shape which is longer than the cells in control group and positive control group. This report implies that pFF of medium follicle size at 200 µg proteins and large follicle size at 200 and 500 µg proteins could be optimized concentration for using as a supplement in culture medium to promote cell growth and development instead of growth hormone from fetal calf serum. It could be applied in cell biotechnology researches. Acknowledgements: The project was funded by a grant from Silpakorn University Research and Development Institute (SURDI) and Faculty of Science, Silpakorn University, Thailand.Keywords: in vitro, porcine follicular fluid protein (pFF), porcine oviductal epithelial cells (pOEC), MTT
Procedia PDF Downloads 145996 Probiotics as an Alternative to Antibiotic Use in Pig Production
Authors: Z. C. Dlamini, R. L. S. Langa, A. I. Okoh, O. A. Aiyegoro
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The indiscriminate usage of antibiotics in swine production have consequential outcomes; such as development of bacterial resistance to prophylactic antibiotics and possibility of antibiotic residues in animal products. The use of probiotics appears to be the most effective procedure with positive metabolic nutritional implications. The aim of this study was to investigate the efficacy of probiotic bacteria (Lactobacillus reuteri ZJ625, Lactobacillus reuteri VB4, Lactobacillus salivarius ZJ614 and Streptococcus salivarius NBRC13956) administered as direct-fed microorganisms in weaned piglets. 45 weaned piglets blocked by weight were dived into 5 treatments groups: diet with antibiotic, diet with no-antibiotic and no probiotic, and diet with probiotic and diet with combination of probiotics. Piglets performance was monitored during the trials. Faecal and Ileum samples were collected for microbial count analysis. Blood samples were collected from pigs at the end of the trial, for analysis of haematological, biochemical and IgG stimulation. The data was analysed by Split-Plot ANOVA using SAS statistically software (SAS 9.3) (2003). The difference was observed between treatments for daily weight and feed conversion ratio. No difference was observed in analysis of faecal samples in regards with bacterial counts, difference was observed in ileums samples with enteric bacteria colony forming unit being lower in P2 treatment group as compared with lactic acid and total bacteria. With exception of globulin and albumin, biochemistry blood parameters were not affected, likewise for haematology, only basophils and segmented neutrophils were differed by having higher concentration in NC treatment group as compared with other treatment groups. Moreover, in IgG stimulation analysis, difference was also observed, with P2 treatment group having high concentration of IgG in P2 treatment group as compared to other groups. The results of this study suggest that probiotics have a beneficial effect on growth performances, blood parameters and IgG stimulation of pigs, most effective when they are administered in synergy form. This means that it is most likely that these probiotics will offer a significant benefit in pig farming by reducing risk of morbidity and mortality and produce quality meat that is more affordable to poorer communities, and thereby enhance South African pig industry’s economy. In addition, these results indicate that there is still more research need to be done on probiotics in regards with, i.e. dosage, shelf life and mechanism of action.Keywords: antibiotics, biochemistry, haematology, IgG-stimulation, microbial count, probiotics
Procedia PDF Downloads 301995 Development of a Natural Anti-cancer Formulation Which Can Target Triple Negative Breast Cancer Stem Cells
Authors: Samashi Munaweera
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Cancer stem cells (CSC) are responsible for the initiation, extensive proliferation and metastasis of cancer. CSCs, including breast cancer stem cells (bCSCs) have a capacity to generate chemo and radiotherapy resistance heterogeneous population of cells. Over-expressed ABCB1 has been reported as a main reason for drug resistance of CSCs via activating drug efflux pumps by creating pores in the cell membrane. The overall efficiency of chemotherapeutic agents might be enhanced by blocking the ABCB protein efflux pump in the CSC membrane. There is an urgent need to search for persuasive natural drugs which can target CSCs. Anti-cancer properties of Hylocereus undatus on cancer CSCs have not yet been studied. In the present study, the anti-cancer effects of the peel and flesh of H. undatus fruit on bCSCs were evaluated with the aim of developing a marketable anti-cancer nutraceutical formulation. The flesh and peel of H. undatus were freeze-dried and sequentially extracted into four different solvents (hexane, chloroform, ethyl acetate and ethanol). All extracts (eight extracts) were dried under reduced pressure, and different concentrations (12.5-400 µg/mL) were treated on bCSCs isolated from a triple-negative chemo-resistant breast cancer phenotype (MDA-MB-231 cells). Anti-proliferative effects of all extracts and paclitaxel (positive control) were determined by a colorimetric assay (WST-1 based). Since peel-chloroform (IC50= 54.8 µg/mL) and flesh-ethyl acetate (IC50= 150.5 µg/mL) extras exerted a potent anti-proliferative effect at 72 h post-incubation, a combinatorial formulation (CF) was developed with the most active peel-chloroform extract and 20 µg/mL of verapamil (a known ABCB1 drug efflux pump blocker) first time in the world. Anti-proliferative effects and pro-apoptotic effects of CF were confirmed by estimating activated caspase3 and caspase7 levels and apoptotic morphological features in the CF-treated bCSCs compared to untreated and only verapamil (20 µg/mL) treated bCSCs, and CF treated normal mammary epithelial cells (MCF-10A). The antiproliferative effects of CF (16.4 µg/mL) are greater than paclitaxel (19.2 µg/mL) and three folds greater than peel-chloroform extract (IC50= 54.8 µg/mL) on bCSCs while exerting less effects on normal cells (> 400 µg/mL). Collectively, CF can be considered as a potential initiative of a nutraceutical formulation that can target CSCs.Keywords: breast cancer stem cells (bCSCs), Hylocereus undatus, combinatorial formulation (CF), ABCB 1 protein, verapamil
Procedia PDF Downloads 28994 Unveiling Comorbidities in Irritable Bowel Syndrome: A UK BioBank Study utilizing Supervised Machine Learning
Authors: Uswah Ahmad Khan, Muhammad Moazam Fraz, Humayoon Shafique Satti, Qasim Aziz
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Approximately 10-14% of the global population experiences a functional disorder known as irritable bowel syndrome (IBS). The disorder is defined by persistent abdominal pain and an irregular bowel pattern. IBS significantly impairs work productivity and disrupts patients' daily lives and activities. Although IBS is widespread, there is still an incomplete understanding of its underlying pathophysiology. This study aims to help characterize the phenotype of IBS patients by differentiating the comorbidities found in IBS patients from those in non-IBS patients using machine learning algorithms. In this study, we extracted samples coding for IBS from the UK BioBank cohort and randomly selected patients without a code for IBS to create a total sample size of 18,000. We selected the codes for comorbidities of these cases from 2 years before and after their IBS diagnosis and compared them to the comorbidities in the non-IBS cohort. Machine learning models, including Decision Trees, Gradient Boosting, Support Vector Machine (SVM), AdaBoost, Logistic Regression, and XGBoost, were employed to assess their accuracy in predicting IBS. The most accurate model was then chosen to identify the features associated with IBS. In our case, we used XGBoost feature importance as a feature selection method. We applied different models to the top 10% of features, which numbered 50. Gradient Boosting, Logistic Regression and XGBoost algorithms yielded a diagnosis of IBS with an optimal accuracy of 71.08%, 71.427%, and 71.53%, respectively. Among the comorbidities most closely associated with IBS included gut diseases (Haemorrhoids, diverticular diseases), atopic conditions(asthma), and psychiatric comorbidities (depressive episodes or disorder, anxiety). This finding emphasizes the need for a comprehensive approach when evaluating the phenotype of IBS, suggesting the possibility of identifying new subsets of IBS rather than relying solely on the conventional classification based on stool type. Additionally, our study demonstrates the potential of machine learning algorithms in predicting the development of IBS based on comorbidities, which may enhance diagnosis and facilitate better management of modifiable risk factors for IBS. Further research is necessary to confirm our findings and establish cause and effect. Alternative feature selection methods and even larger and more diverse datasets may lead to more accurate classification models. Despite these limitations, our findings highlight the effectiveness of Logistic Regression and XGBoost in predicting IBS diagnosis.Keywords: comorbidities, disease association, irritable bowel syndrome (IBS), predictive analytics
Procedia PDF Downloads 119993 Nonlinear Interaction of Free Surface Sloshing of Gaussian Hump with Its Container
Authors: Mohammad R. Jalali
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Movement of liquid with a free surface in a container is known as slosh. For instance, slosh occurs when water in a closed tank is set in motion by a free surface displacement, or when liquid natural gas in a container is vibrated by an external driving force, such as an earthquake or movement induced by transport. Slosh is also derived from resonant switching of a natural basin. During sloshing, different types of motion are produced by energy exchange between the liquid and its container. In present study, a numerical model is developed to simulate the nonlinear even harmonic oscillations of free surface sloshing of an initial disturbance to the free surface of a liquid in a closed square basin. The response of the liquid free surface is affected by amplitude and motion frequencies of its container; therefore, sloshing involves complex fluid-structure interactions. In the present study, nonlinear interaction of free surface sloshing of an initial Gaussian hump with its uneven container is predicted numerically. For this purpose, Green-Naghdi (GN) equations are applied as governing equation of fluid field to produce nonlinear second-order and higher-order wave interactions. These equations reduce the dimensions from three to two, yielding equations that can be solved efficiently. The GN approach assumes a particular flow kinematic structure in the vertical direction for shallow and deep-water problems. The fluid velocity profile is finite sum of coefficients depending on space and time multiplied by a weighting function. It should be noted that in GN theory, the flow is rotational. In this study, GN numerical simulations of initial Gaussian hump are compared with Fourier series semi-analytical solutions of the linearized shallow water equations. The comparison reveals that satisfactory agreement exists between the numerical simulation and the analytical solution of the overall free surface sloshing patterns. The resonant free surface motions driven by an initial Gaussian disturbance are obtained by Fast Fourier Transform (FFT) of the free surface elevation time history components. Numerically predicted velocity vectors and magnitude contours for the free surface patterns indicate that interaction of Gaussian hump with its container has localized effect. The result of this sloshing is applicable to the design of stable liquefied oil containers in tankers and offshore platforms.Keywords: fluid-structure interactions, free surface sloshing, Gaussian hump, Green-Naghdi equations, numerical predictions
Procedia PDF Downloads 398992 Experimental Investigation on the Effect of Prestress on the Dynamic Mechanical Properties of Conglomerate Based on 3D-SHPB System
Authors: Wei Jun, Liao Hualin, Wang Huajian, Chen Jingkai, Liang Hongjun, Liu Chuanfu
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Kuqa Piedmont is rich in oil and gas resources and has great development potential in Tarim Basin, China. However, there is a huge thick gravel layer developed with high content, wide distribution and variation in size of gravel, leading to the condition of strong heterogeneity. So that, the drill string is in a state of severe vibration and the drill bit is worn seriously while drilling, which greatly reduces the rock-breaking efficiency, and there is a complex load state of impact and three-dimensional in-situ stress acting on the rock in the bottom hole. The dynamic mechanical properties and the influencing factors of conglomerate, the main component of gravel layer, are the basis of engineering design and efficient rock breaking method and theoretical research. Limited by the previously experimental technique, there are few works published yet about conglomerate, especially rare in dynamic load. Based on this, a kind of 3D SHPB system, three-dimensional prestress, can be applied to simulate the in-situ stress characteristics, is adopted for the dynamic test of the conglomerate. The results show that the dynamic strength is higher than its static strength obviously, and while the three-dimensional prestress is 0 and the loading strain rate is 81.25~228.42 s-1, the true triaxial equivalent strength is 167.17~199.87 MPa, and the strong growth factor of dynamic and static is 1.61~1.92. And the higher the impact velocity, the greater the loading strain rate, the higher the dynamic strength and the greater the failure strain, which all increase linearly. There is a critical prestress in the impact direction and its vertical direction. In the impact direction, while the prestress is less than the critical one, the dynamic strength and the loading strain rate increase linearly; otherwise, the strength decreases slightly and the strain rate decreases rapidly. In the vertical direction of impact load, the strength increases and the strain rate decreases linearly before the critical prestress, after that, oppositely. The dynamic strength of the conglomerate can be reduced properly by reducing the amplitude of impact load so that the service life of rock-breaking tools can be prolonged while drilling in the stratum rich in gravel. The research has important reference significance for the speed-increasing technology and theoretical research while drilling in gravel layer.Keywords: huge thick gravel layer, conglomerate, 3D SHPB, dynamic strength, the deformation characteristics, prestress
Procedia PDF Downloads 209991 A Post-Colonial Reading of Maria Edgeworth's Anglo-Irish Novels: Castle Rackrent and the Absentee
Authors: Al. Harshan, Hazamah Ali Mahdi
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The Big House literature embodies Irish history. It requires a special dimension of moral and social significance in relation to its owners. The Big House is a metaphor for the decline of the protestant Ascendancy that ruled in a catholic country and oppressed a native people. In the tradition of the Big House fiction, Maria Edgeworth's Castle Rackrent and the Absentee explore the effect of the Anglo-Irish protestant Ascendancy as it governed and misgoverned Ireland. Edgeworth illustrates the tradition of the Big House as a symbol of both a personal and historical theme. This paper provides a reading of Castle Rackrent and The Absentee from a post-colonial perspective. The paper maintains that Edgeworth's novel contain elements of a radical critique of the colonialist enterprise. In our postcolonial reading of Maria Edgeworth's novels, one that goes beyond considering works as those of Sir Walter Scoot, regional evidence has been found of Edgeworth's colonial ideology. The significance of Castle Rackrent lies mainly in the fact that is the first English novel to speak in the voice of the colonized Irish. What is more important is that the irony and the comic aspect of the novel comes from its Irish narrator (Thady Quirk) and its Irish setting Ireland. Edgeworth reveals the geographical 'other' to her English reader, by placing her colonized Irish narrator and his son, Jason Quirk, in a position of inferiority to emphasize the gap between Englishness and Irishness. Furthermore, this satirical aspect is a political one. It works to create and protect the superiority of the domestic English reader over the Irish subject. In other words, the implication of the colonial system of the novel and of its structure of dominance and subordination is overlooked by its comic dimension. The matrimonial plot in the Absentee functions as an imperial plot, constructing Ireland as a complementary but ever unequal partner in the family of Great Britain. This imperial marriage works hegemonically to produce the domestic stability considered so crucial to national and colonial stability. Moreover, in order to achieve her proper imperial plot, Edgeworth reconciliation of England and Ireland is seen in the marriage of the Anglo-Irish (hero/Colambre) with the Irish (heroine/Grace Nugent), and the happy bourgeois family; consequently, it becomes the model for colonizer-colonized relationships. Edgeworth must establish modes of legitimate behavior for women and men. The Absentee explains more purposely how familial reorganization is dependent on the restitution of masculine authority and advantage, particularly for Irish community.Keywords: Maria Edgeworth, post-colonial, reading, Irish
Procedia PDF Downloads 544990 The Efficacy of Preoperative Thermal Pulsation Treatment in Reducing Post Cataract Surgery Dry Eye Disease: A Systematic Review and Meta-analysis
Authors: Lugean K. Alomari, Rahaf K. Sharif, Basil K. Alomari, Hind M. Aljabri, Faisal F. Aljahdali, Amal A. Alomari, Saeed A. Alghamdi
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Background: The thermal pulsation system is a therapy that uses heat and massage to treat dry eye disease; thus, some trials have been published to compare it with the conventional treatment. The aim of this study is to conduct a systematic review and meta-analysis comparing the efficacy of thermal pulsation systems with conventional treatment in patients undergoing cataract surgery. Methods: Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for eligible trials. We included three randomized controlled trials (RCTs) that compared the thermal pulsation system with the conventional treatment in patients undergoing cataract surgery. A table of characteristics was plotted, and the Quality of the studies was assessed using the Cochrane risk-of-bias tool for randomized trials (RoB 2). Forest plots were plotted using the Random-effect Inverse Variance method. χ2 test and the Higgins-I-squared (I2) model were used to assess heterogeneity. A total of 201 cataract surgery patients were included, with 105 undergoing preoperative pulsation therapy and 96 receiving conventional treatment. Demographic analysis revealed comparable distributions across groups. Results: All the studies in our analysis are of good quality with a low risk of bias. A total of 201 patients were included in the analysis, out of which 105 underwent pulsation therapy, and 95 were in the control group. Tear Break-up Time (TBUT) analysis revealed no significant baseline differences, except pulsation therapy being better at 1 month. (SMD 0.42 [95%CI 0.14 - 0.70] p=0.004). This positive trend continued at three months (SMD 0.52 [95% CI (0.20 – 0.84)] p=0.002). Corneal fluorescein staining scores and Meibomian gland-yielding secretion scores showed no significant differences at baseline. However, at one month, pulsation therapy significantly improved Meibomian gland function (SMD -0.86 [95% CI (-1.20 - -0.53)] p<0.00001), indicating a reduced risk of dry eye syndrome. Conclusion: Preoperative pulsation therapy appears to enhance post-cataract surgery outcomes, particularly in terms of tear film stability and Meibomian gland secretory function. The sustained positive effects observed at one and three months post-surgery suggest the potential for long-term benefits.Keywords: lipiflow, cataract, thermal pulsation, dry eye
Procedia PDF Downloads 21989 High Acid-Stable α-Amylase Production by Milk in Liquid Culture
Authors: Shohei Matsuo, Saki Mikai, Hiroshi Morita
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Objectives: Shochu is a popular Japanese distilled spirits. In the production of shochu, the filamentous fungus Aspergillus kawachii has traditionally been used. A. kawachii produces two types of starch hydrolytic enzymes, α-amylase (enzymatic liquefaction) and glucoamylase (enzymatic saccharification). Liquid culture system is a relatively easy microorganism to ferment with relatively low cost of production compared for solid culture. In liquid culture system, acid-unstable α-amylase (α-A) was produced abundantly, but, acid-stable α-amylase (Aα-A) was not produced. Since there is high enzyme productivity, most in shochu brewing have been adopted by a solid culture method. In this study, therefore, we investigated production of Aα-A in liquid culture system. Materials and methods: Microorganism Aspergillus kawachii NBRC 4308 was used. The mold was cultured at 30 °C for 7~14 d to allow formation of conidiospores on slant agar medium. Liquid Culture System: A. kawachii was cultured in a 100 ml of following altered SLS medium: 1.0 g of rice flour, 0.1 g of K2HPO4, 0.1 g of KCl, 0.6 g of tryptone, 0.05 g of MgSO4・7H2O, 0.001 g of FeSO4・7H2O, 0.0003 g of ZnSO4・7H2O, 0.021 g of CaCl2, 0.33 of citric acid (pH 3.0). The pH of the medium was adjusted to the designated value with 10 % HCl solution. The cultivation was shaking at 30 °C and 200 rpm for 72 h. It was filtered to obtain a crude enzyme solution. Aα-A assay: The crude enzyme solution was analyzed. An acid-stable α-amylase activity was carried out using an α-amylase assay kit (Kikkoman Corporation, Noda, Japan). It was conducted after adding 9 ml of 100 mM acetate buffer (pH 3.0) to 1 ml of the culture product supernatant and acid treatment at 37°C for 1 h. One unit of a-amylase activity was defined as the amount of enzyme that yielded 1 mmol of 2-chloro-4-nitrophenyl 6-azide-6-deoxy-b-maltopentaoside (CNP) per minute. Results and Conclusion: We experimented with co-culture of A. kawachii and lactobacillus in order to get control of pH in altered SLS medium. However, high production of acid-stable α-amylase was not obtained. We experimented with yoghurt or milk made an addition to liquid culture. The result indicated that high production of acid-stable α-amylase (964 U/g-substrate) was obtained when milk made an addition to liquid culture. Phosphate concentration in the liquid medium was a major cause of increased acid-stable α-amylase activity. In liquid culture, acid-stable α-amylase activity was enhanced by milk, but Fats and oils in the milk were oxidized. In addition, Tryptone is not approved as a food additive in Japan. Thus, alter SLS medium added to skim milk excepting for the fats and oils in the milk instead of tryptone. The result indicated that high production of acid-stable α-amylase was obtained with the same effect as milk.Keywords: acid-stable α-amylase, liquid culture, milk, shochu
Procedia PDF Downloads 284988 The Impact of AI on Consumers’ Morality: An Empirical Evidence
Authors: Mingxia Zhu, Matthew Tingchi Liu
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AI grows gradually in the market with its efficiency and accuracy, influencing people’s perceptions, attitude, and even consequential behaviors. Current study extends prior research by focusing on AI’s impact on consumers’ morality. First, study 1 tested individuals’ believes about AI and human’s moral perceptions and people’s attribution of moral worth to AI and human. Moral perception refers to a computational system an entity maintains to detect and identify moral violations, while moral worth here denotes whether individual regard an entity as worthy of moral treatment. To identify the effect of AI on consumers’ morality, two studies were employed. Study 1 is a within-subjects survey, while study 2 is an experimental study. In the study 1, one hundred and forty participants were recruited through online survey company in China (M_age = 27.31 years, SD = 7.12 years; 65% female). The participants were asked to assign moral perception and moral worth to AI and human. A paired samples t-test reveals that people generally regard that human has higher moral perception (M_Human = 6.03, SD = .86) than AI (M_AI = 2.79, SD = 1.19; t(139) = 27.07, p < .001; Cohen’s d = 1.41). In addition, another paired samples t-test results showed that people attributed higher moral worth to the human personnel (M_Human = 6.39, SD = .56) compared with AIs (M_AI = 5.43, SD = .85; t(139) = 12.96, p < .001; d = .88). In the next study, two hundred valid samples were recruited from survey company in China (M_age = 27.87 years, SD = 6.68 years; 55% female) and the participants were randomly assigned to two conditions (AI vs. human). After viewing the stimuli of human versus AI, participants are informed that one insurance company would determine the price purely based on their declaration. Therefore, their open-ended answers were coded into ethical, honest behavior and unethical, dishonest behavior according to the design of prior literature. A Chi-square analysis revealed that 64% of the participants would immorally lie towards AI insurance inspector while 42% of participants reported deliberately lower mileage facing with human inspector (χ^2 (1) = 9.71, p = .002). Similarly, the logistic regression results suggested that people would significantly more likely to report fraudulent answer when facing with AI (β = .89, odds ratio = 2.45, Wald = 9.56, p = .002). It is demonstrated that people would be more likely to behave unethically in front of non-human agents, such as AI agent, rather than human. The research findings shed light on new practical ethical issues in human-AI interaction and address the important role of human employees during the process of service delivery in the new era of AI.Keywords: AI agent, consumer morality, ethical behavior, human-AI interaction
Procedia PDF Downloads 82987 Identification of Potent and Selective SIRT7 Anti-Cancer Inhibitor via Structure-Based Virtual Screening and Molecular Dynamics Simulation
Authors: Md. Fazlul Karim, Ashik Sharfaraz, Aysha Ferdoushi
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Background: Computational medicinal chemistry approaches are used for designing and identifying new drug-like molecules, predicting properties and pharmacological activities, and optimizing lead compounds in drug development. SIRT7, a nicotinamide adenine dinucleotide (NAD+)-dependent deacylase which regulates aging, is an emerging target for cancer therapy with mounting evidence that SIRT7 downregulation plays important roles in reversing cancer phenotypes and suppressing tumor growth. Activation or altered expression of SIRT7 is associated with the progression and invasion of various cancers, including liver, breast, gastric, prostate, and non-small cell lung cancer. Objectives: The goal of this work was to identify potent and selective bioactive candidate inhibitors of SIRT7 by in silico screening of small molecule compounds obtained from Nigella sativa (N. sativa). Methods: SIRT7 structure was retrieved from The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB), and its active site was identified using CASTp and metaPocket. Molecular docking simulation was performed with PyRx 0.8 virtual screening software. Drug-likeness properties were tested using SwissADME and pkCSM. In silico toxicity was evaluated by Osiris Property Explorer. Bioactivity was predicted by Molinspiration software. Antitumor activity was screened for Prediction of Activity Spectra for Substances (PASS) using Way2Drug web server. Molecular dynamics (MD) simulation was carried out by Desmond v3.6 package. Results: A total of 159 bioactive compounds from the N. Sativa were screened against the SIRT7 enzyme. Five bioactive compounds: chrysin (CID:5281607), pinocembrin (CID:68071), nigellidine (CID:136828302), nigellicine (CID:11402337), and epicatechin (CID:72276) were identified as potent SIRT7 anti-cancer candidates after docking score evaluation and applying Lipinski's Rule of Five. Finally, MD simulation identified Chrysin as the top SIRT7 anti-cancer candidate molecule. Conclusion: Chrysin, which shows a potential inhibitory effect against SIRT7, can act as a possible anti-cancer drug candidate. This inhibitor warrants further evaluation to check its pharmacokinetics and pharmacodynamics properties both in vitro and in vivo.Keywords: SIRT7, antitumor, molecular docking, molecular dynamics simulation
Procedia PDF Downloads 79986 Investigation of the Relationship between Digital Game Playing, Internet Addiction and Perceived Stress Levels in University Students
Authors: Sevim Ugur, Cemile Kutmec Yilmaz, Omer Us, Sevdenur Koksaldi
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Aim: This study aims to investigate the effect of digital game playing and Internet addiction on perceived stress levels in university students. Method: The descriptive study was conducted through face-to-face interview method with a total of 364 university students studying at Aksaray University between November 15 and December 30, 2017. The research data were collected using personal information form, a questionnaire to determine the characteristics of playing digital game, the Internet addiction scale and the perceived stress scale. In the evaluation of the data, Mann-Whitney U test was used for two-group comparison of the sample with non-normal distribution, Kruskal-Wallis H-test was used in the comparison of more than two groups, and the Spearman correlation test was used to determine the relationship between Internet addiction and the perceived stress level. Results: It was determined that the mean age of the students participated in the study was 20.13 ± 1.7 years, 67.6% was female, 35.7% was sophomore, and 62.1% had an income 500 TL or less. It was found that 83.5% of the students use the Internet every day and 70.6% uses the Internet for 5 hours or less per day. Of the students, 12.4% prefers digital games instead of spending time outdoors, 8% plays a game as the first activity in leisure time, 12.4% plays all day, 15.7% feels anger when he/she is prevented from playing, 14.8% prefers playing games to get away from his/her problems, 23.4% had his/her school achievement affected negatively because of game playing, and 8% argues with family members due to the time spent for gaming. Students who play games on the computer for a long time were found to feel back pain (30.8%), headache (28.6%), insomnia (26.9%), dryness and pain in the eyes (26.6%), pain in the wrist (21.2%), feeling excessive tension and anger (16.2%), humpback (12.9), vision loss (9.6%) and pain in the wrist and fingers (7.4%). In our study, students' Internet addiction scale mean score was found to be 45.47 ± 16.1 and mean perceived stress scale score was 28.56 ± 2.7. A significant and negative correlation (p=0.037) was found between the total score of the Internet addiction scale and the total score of the perceived stress scale (r=-0.110). Conclusion: It was found in the study that Internet addiction and perceived stress of the students were at a moderate level and that there was a negative correlation between Internet addiction and perceived stress levels. Internet addiction was found to increase with the increasing perceived stress levels of students, and students were found to have health problems such as back pain, dryness in the eyes, pain, insomnia, headache, and humpback. Therefore, it is recommended to inform students about different coping methods other than spending time on the Internet to cope with the stress they perceive.Keywords: digital game, internet addiction, student, stress level
Procedia PDF Downloads 288985 Calibration of Contact Model Parameters and Analysis of Microscopic Behaviors of Cuxhaven Sand Using The Discrete Element Method
Authors: Anjali Uday, Yuting Wang, Andres Alfonso Pena Olare
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The Discrete Element Method is a promising approach to modeling microscopic behaviors of granular materials. The quality of the simulations however depends on the model parameters utilized. The present study focuses on calibration and validation of the discrete element parameters for Cuxhaven sand based on the experimental data from triaxial and oedometer tests. A sensitivity analysis was conducted during the sample preparation stage and the shear stage of the triaxial tests. The influence of parameters like rolling resistance, inter-particle friction coefficient, confining pressure and effective modulus were investigated on the void ratio of the sample generated. During the shear stage, the effect of parameters like inter-particle friction coefficient, effective modulus, rolling resistance friction coefficient and normal-to-shear stiffness ratio are examined. The calibration of the parameters is carried out such that the simulations reproduce the macro mechanical characteristics like dilation angle, peak stress, and stiffness. The above-mentioned calibrated parameters are then validated by simulating an oedometer test on the sand. The oedometer test results are in good agreement with experiments, which proves the suitability of the calibrated parameters. In the next step, the calibrated and validated model parameters are applied to forecast the micromechanical behavior including the evolution of contact force chains, buckling of columns of particles, observation of non-coaxiality, and sample inhomogeneity during a simple shear test. The evolution of contact force chains vividly shows the distribution, and alignment of strong contact forces. The changes in coordination number are in good agreement with the volumetric strain exhibited during the simple shear test. The vertical inhomogeneity of void ratios is documented throughout the shearing phase, which shows looser structures in the top and bottom layers. Buckling of columns is not observed due to the small rolling resistance coefficient adopted for simulations. The non-coaxiality of principal stress and strain rate is also well captured. Thus the micromechanical behaviors are well described using the calibrated and validated material parameters.Keywords: discrete element model, parameter calibration, triaxial test, oedometer test, simple shear test
Procedia PDF Downloads 121984 A Comparative Analysis of Liberation and Contemplation in Sankara and Aquinas
Authors: Zeite Shumneiyang Koireng
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Liberation is the act of liberating or the state of being liberated. Indian philosophy, in general, understands liberation as moksa, which etymological is derived from the Sanskrit root muc+ktin meaning to loose, set free, to let go, discharge, release, liberate, deliver, etc. According to Indian schools of thought, moksa is the highest value on realizing which nothing remains to be realized. It is the cessation of birth and death, all kinds of pain and at the same time, it is the realization of one’s own self. Sankara’s Advaita philosophy is based on the following propositions: Brahman is the only Reality; the world has apparent reality, and the soul is not different from Brahman. According to Sankara, Brahman is the basis on which the world form appears; it is the sustaining ground of all various modification. It is the highest self and the self of all reveals himself by dividing himself [ as it was in the form of various objects] in multiple ways. The whole world is the manifestation of the Supreme Being. Brahman modifying itself into the Atman or internal self of all things is the world. Since Brahman is the Upadhana karana of the world, the sruti speaks of the world as the modification of Brahman into the Atman of the effect. Contemplation as the fulfillment of man finds a radical foundation in Aquinas teaching concerning the natural end or as he also referred to it, natural desire. The third book of the Summa Contra Gentiles begins the study of happiness with a consideration of natural desire. According to him, all creatures, even those devoid of understanding are ordered to God as an ultimate end. Intrinsically, a part of every nature is a tendency or inclination, originating in the natural form and tendency toward the end for which the possessor of nature exists. It is the study of the nature and finality of inclination that Aquinas establishes through an argument of induction man’s Contemplation of God as the fulfillment of his nature. The present paper is attempted to critically approach two important, seminal and originated thought, representing Indian and Western traditions which mark on the thinking of their respective times. Both these thoughts- Advaitic concept of Liberation in the Indian tradition and the concept of Contemplation in Thomas Aquinas’ Summa Contra Gentiles’- confront directly the question of the ultimate meaning of human existence. According to Sankara, it is knowledge and knowledge alone which is the means of moksa and the highest knowledge is moksa itself. Liberation in Sankara Vedanta is attained as a process of purification of self, which gradually and increasingly turns into purer and purer intentional construction. Man’s inner natural tendency for Aquinas is towards knowledge. The human subject is driven to know more and more about reality and in particular about the highest reality. Contemplation of this highest reality is fulfillment in the philosophy of Aquinas. Rather, Contemplation is the perfect activity in man’s present state of existence.Keywords: liberation, Brahman, contemplation, fulfillment
Procedia PDF Downloads 193983 Metagenomic Assessment of the Effects of Genetically Modified Crops on Microbial Ecology and Physicochemical Properties of Soil
Authors: Falana Yetunde Olaitan, Ijah U. J. J, Solebo Shakirat O.
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Genetically modified crops are already phenomenally successful and are grown worldwide in more than eighteen countries on more than 67 million hectares. Nigeria, in October 2018, approved Bacillus thuringiensis (Bt) cotton and maize; therefore, the need to carry out environmental risk assessment studies. A total of 15 4L octagonal ceramic pots were filled with 4kg of soil and placed on the bench in 2 rows of 10 pots each and the 3rd row of 5 pots, 1st-row pots were used to plant GM cotton seeds, while the 2nd-row pots were used for non-GM cotton seeds and the 3rd row of 5 pots served as control, all in the screen house. Soil samples for metagenomic DNA extraction were collected at random and at the monthly interval after planting at a distance of 2mm from the plant’s root and at a depth of 10cm using a sterile spatula. Soil samples for physicochemical analysis were collected before planting and after harvesting the GM and non-GM crops as well as from the control soil. The DNA was extracted, quantified and sequenced; Sample 1A (DNA from GM cotton Soil at 1st interval) gave the lowest sequence read with 0.853M while sample 2B (DNA from GM cotton Soil at 2nd interval) gave the highest with 5.785M, others gave between 1.8M and 4.7M. The samples treatment were grouped into four, Group 1 (GM cotton soil from 1 to 3 intervals) had between 800,000 and 5,700,000 strains of microbes (SOM), Group 2 (non GM cotton soil from 1 to 3 intervals) had between 1,400,600 and 4,200,000 SOM, Group 3 (control soil) had between 900,000 and 3,600,000 SOM and Group 4 (initial soil) had between 3,700,000 and 4,000,000 SOM. The microbes observed were predominantly bacteria (including archaea), fungi, dark matter alongside protists and phages. The predominant bacterial groups were the Terrabacteria (Bacillus funiculus, Bacillus sp.), the Proteobacteria (Microvirga massiliensis, sphingomonas sp.) and the Archaea (Nitrososphaera sp.), while the fungi were Aspergillus fischeri and Fusarium falciforme. The comparative analysis between groups was done using JACCARD PERMANOVA beta diversity analysis at P-value not more than 0.76 and there was no significant pair found. The pH for initial, GM cotton, non-GM cotton and control soil were 6.28, 6.26, 7.25, 8.26 and the percentage moisture was 0.63, 0.78, 0.89 and 0.82, respectively, while the percentage Nitrogen was observed to be 17.79, 1.14, 1.10 and 0.56 respectively. Other parameters include, varying concentrations of Potassium (0.46, 1,284.47, 1,785.48, 1,252.83 mg/kg) and Phosphorus (18.76, 17.76, 16.87, 15.23 mg/kg) were recorded for the four treatments respectively. The soil consisted mainly of silt (32.09 to 34.66%) and clay (58.89 to 60.23%), reflecting the soil texture as silty – clay. The results were then tested with ANOVA at less than 0.05 P-value and no pair was found to be significant as well. The results suggest that the GM crops have no significant effect on microbial ecology and physicochemical properties of the soil and, in turn, no direct or indirect effects on human health.Keywords: genetically modified crop, microbial ecology, physicochemical properties, metagenomics, DNA, soil
Procedia PDF Downloads 145982 Improvement in the Photocatalytic Activity of Nanostructured Manganese Ferrite – Type of Materials by Mechanochemical Activation
Authors: Katerina Zaharieva, Katya Milenova, Zara Cherkezova-Zheleva, Alexander Eliyas, Boris Kunev, Ivan Mitov
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The synthesized nanosized manganese ferrite-type of samples have been tested as photocatalysts in the reaction of oxidative degradation of model contaminant Reactive Black 5 (RB5) dye in aqueous solutions under UV irradiation. As it is known this azo dye is applied in the textile-coloring industry and it is discharged into the waterways causing pollution. The co-precipitation procedure has been used for the synthesis of manganese ferrite-type of materials: Sample 1 - Mn0.25Fe2.75O4, Sample 2 - Mn0.5Fe2.5O4 and Sample 3 - MnFe2O4 from 0.03M aqueous solutions of MnCl2•4H2O, FeCl2•4H2O and/or FeCl3•6H2O and 0.3M NaOH in appropriate amounts. The mechanochemical activation of co-precipitated ferrite-type of samples has been performed in argon (Samples 1 and 2) or in air atmosphere (Sample 3) for 2 hours at a milling speed of 500 rpm. The mechano-chemical treatment has been carried out in a high energy planetary ball mill type PM 100, Retsch, Germany. The mass ratio between balls and powder was 30:1. As a result mechanochemically activated Sample 4 - Mn0.25Fe2.75O4, Sample 5 - Mn0.5Fe2.5O4 and Sample 6 - MnFe2O4 have been obtained. The synthesized manganese ferrite-type photocatalysts have been characterized by X-ray diffraction method and Moessbauer spectroscopy. The registered X-ray diffraction patterns and Moessbauer spectra of co-precipitated ferrite-type of materials show the presence of manganese ferrite and additional akaganeite phase. The presence of manganese ferrite and small amounts of iron phases is established in the mechanochemically treated samples. The calculated average crystallite size of manganese ferrites varies within the range 7 – 13 nm. This result is confirmed by Moessbauer study. The registered spectra show superparamagnetic behavior of the prepared materials at room temperature. The photocatalytic investigations have been made using polychromatic UV-A light lamp (Sylvania BLB, 18 W) illumination with wavelength maximum at 365 nm. The intensity of light irradiation upon the manganese ferrite-type photocatalysts was 0.66 mW.cm-2. The photocatalytic reaction of oxidative degradation of RB5 dye was carried out in a semi-batch slurry photocatalytic reactor with 0.15 g of ferrite-type powder, 150 ml of 20 ppm dye aqueous solution under magnetic stirring at rate 400 rpm and continuously feeding air flow. The samples achieved adsorption-desorption equilibrium in the dark period for 30 min and then the UV-light was turned on. After regular time intervals aliquot parts from the suspension were taken out and centrifuged to separate the powder from solution. The residual concentrations of dye were established by a UV-Vis absorbance single beam spectrophotometer CamSpec M501 (UK) measuring in the wavelength region from 190 to 800 nm. The photocatalytic measurements determined that the apparent pseudo-first-order rate constants calculated by linear slopes approximating to first order kinetic equation, increase in following order: Sample 3 (1.1х10-3 min-1) < Sample 1 (2.2х10-3 min-1) < Sample 2 (3.3 х10-3 min-1) < Sample 4 (3.8х10-3 min-1) < Sample 6 (11х10-3 min-1) < Sample 5 (15.2х10-3 min-1). The mechanochemically activated manganese ferrite-type of photocatalyst samples show significantly higher degree of oxidative degradation of RB5 dye after 120 minutes of UV light illumination in comparison with co-precipitated ferrite-type samples: Sample 5 (92%) > Sample 6 (91%) > Sample 4 (63%) > Sample 2 (53%) > Sample 1 (42%) > Sample 3 (15%). Summarizing the obtained results we conclude that the mechanochemical activation leads to a significant enhancement of the degree of oxidative degradation of the RB5 dye and photocatalytic activity of tested manganese ferrite-type of catalyst samples under our experimental conditions. The mechanochemically activated Mn0.5Fe2.5O4 ferrite-type of material displays the highest photocatalytic activity (15.2х10-3 min-1) and degree of oxidative degradation of the RB5 dye (92%) compared to the other synthesized samples. Especially a significant improvement in the degree of oxidative degradation of RB5 dye (91%) has been determined for mechanochemically treated MnFe2O4 ferrite-type of sample with the highest extent of substitution of iron ions by manganese ions than in the case of the co-precipitated MnFe2O4 sample (15%). The mechanochemically activated manganese ferrite-type of samples show good photocatalytic properties in the reaction of oxidative degradation of RB5 azo dye in aqueous solutions and it could find potential application for dye removal from wastewaters originating from textile industry.Keywords: nanostructured manganese ferrite-type materials, photocatalytic activity, Reactive Black 5, water treatment
Procedia PDF Downloads 347