Search results for: secondary compounds
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5258

Search results for: secondary compounds

488 The Situation of Transgender Individuals Was Worsened During Covid-19

Authors: Kajal Attri

Abstract:

Introduction: Transgender people are considered third gender in India, although they still face identification issues and alienated from society. Furthermore, they face several challenges, including discrimination in employment, resources, education, and property as a result, most transgender people make a living through begging at traffic lights, trains, and buses; attending auspicious occasions such as childbirth and weddings; and engaging in sex work, which includes both home-based and street-based sex work. During COVID-19, maintaining social distance exacerbates transgender people's circumstances and prevents them from accessing health care services, sexual reassignment surgery, identity-based resources, government security, and financial stability. Nonetheless, the pandemic raised unfavorable attitudes about transgender persons, such as unsupportive family members and trouble forming emotional relationships. This study focuses on how we missed transgender people during COVID-19 to provide better facilities to cope with this situation when they are already the most vulnerable segment of the society. Methodology: The research was conducted using secondary data from published publications and grey literature obtained from four databases: Pubmed, Psychinfo, Science direct, and Google scholar. The literature included total 25 articles that met the inclusion criteria for a review. Result and Discussion: Transgender people, who are considered the most vulnerable sector of society, have already faced several obstacles as a result of the outbreak. The analysis underscores the difficulties that transgender persons faced during COVID-19, such as, They had trouble accessing the government's social security programmes during the lockdown, which provide rations and pensions since they lack the necessary identifying cards. The impact of COVID-19 leaves transgender people at heightened risk of poverty and ill health because they exist on the margins of society, those livelihood base on sex work, begging, and participation on auspicious occasions. They had a significant risk of contracting SARS-CoV2 because they lived in congested areas or did not have permanent shelter, and they were predominantly infected with HIV, cancer, and other non-communicable illnesses. The pandemic raised unfavorable attitudes about transgender persons, such as unsupportive family members and trouble forming emotional relationships. Conclusion: The study comes forward with useful suggestions based on content analysis and information to reduce the existing woes of transgenders during any pandemic like COVID-19.

Keywords: COVID-19, transgender, lockdown, transwomen, stigmatization

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487 Astronomy in the Education Area: A Narrative Review

Authors: Isabella Lima Leite de Freitas

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The importance of astronomy for humanity is unquestionable. Despite being a robust science, capable of bringing new discoveries every day and quickly increasing the ability of researchers to understand the universe more deeply, scientific research in this area can also help in various applications outside the domain of astronomy. The objective of this study was to review and conduct a descriptive analysis of published studies that presented the importance of astronomy in the area of education. A narrative review of the literature has been performed, considering the articles published in the last five years. As astronomy involves the study of physics, chemistry, biology, mathematics and technology, one of the studies evaluated presented astronomy as the gateway to science, demonstrating the presence of astronomy in 52 school curricula in 37 countries, with celestial movement the dominant content area. Another intervention study, evaluating individuals aged 4-5 years, demonstrated that the attribution of personal characteristics to cosmic bodies, in addition to the use of comprehensive astronomy concepts, favored the learning of science in preschool-age children, considering the use of practical activities of accompaniment and free drawing. Aiming to measure scientific literacy, another study developed in Turkey, motivated the authorities of this country to change the teaching materials and curriculum of secondary schools after the term “astronomy” appeared as one of the most attractive subjects for young people aged 15 to 24. There are also reports in the literature of the use of pedagogical tools, such as the representation of the Solar System on a human scale, where students can walk along the orbits of the planets while studying the laws of dynamics. The use of this tool favored the teaching of the relationship between distance, duration and speed over the period of the planets, in addition to improving the motivation and well-being of students aged 14-16. An important impact of astronomy on education was demonstrated in the study that evaluated the participation of high school students in the Astronomical Olympiads and the International Astronomy Olympiad. The study concluded that these Olympics have considerable influence on students who pursue a career in teaching or research later on, many of whom are in the area of astronomy itself. In addition, the literature indicates that the teaching of astronomy in the digital age has facilitated the availability of data for researchers, but also for the general population. This fact can increase even more the curiosity that the astronomy area has always instilled in people and promote the dissemination of knowledge on an expanded scale. Currently, astronomy has been considered an important ally in strengthening the school curricula of children, adolescents and young adults. This has been used as teaching tools, in addition to being extremely useful for scientific literacy, being increasingly used in the area of education.

Keywords: astronomy, education area, teaching, review

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486 The Importance of Developing Pedagogical Agency Capacities in Initial Teacher Formation: A Critical Approach to Advance in Social Justice

Authors: Priscilla Echeverria

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This paper addresses initial teacher formation as a formative space in which pedagogy students develop a pedagogical agency capacity to contribute to social justice, considering ethical, political, and epistemic dimensions. This paper is structured by discussing first the concepts of agency, pedagogical interaction, and social justice from a critical perspective; and continues offering preliminary results on the capacity of pedagogical agency in novice teachers after the analysis of critical incidents as a research methodology. This study is motivated by the concern that responding to the current neoliberal scenario, many initial teacher formation (ITF) programs have reduced the meaning of education to instruction, and pedagogy to methodology, favouring the formation of a technical professional over a reflective or critical one. From this concern, this study proposes that the restitution of the subject is an urgent task in teacher formation, so it is essential to enable him in his capacity for action and advance in eliminating institutionalized oppression insofar as it affects that capacity. Given that oppression takes place in human interaction, through this work, I propose that initial teacher formation develops sensitivity and educates the gaze to identify oppression and take action against it, both in pedagogical interactions -which configure political, ethical, and epistemic subjectivities- as in the hidden and official curriculum. All this from the premise that modelling democratic and dialogical interactions are basic for any program that seeks to contribute to a more just and empowered society. The contribution of this study lies in the fact that it opens a discussion in an area about which we know little: the impact of the type of interactions offered by university teaching at ITF on the capacity of future teachers to be pedagogical agents. For this reason, this study seeks to gather evidence of the result of this formation, analysing the capacity of pedagogical agency of novice teachers, or, in other words, how capable the graduates of secondary pedagogies are in their first pedagogical experiences to act and make decisions putting the formative purposes that they are capable of autonomously defining before technical or bureaucratic issues imposed by the curriculum or the official culture. This discussion is part of my doctoral research, "The importance of developing the capacity for ethical-political-epistemic agency in novice teachers during initial teacher formation to contribute to social justice", which I am currently developing in the Educational Research program of the University of Lancaster, United Kingdom, as a Conicyt fellow for the 2019 cohort.

Keywords: initial teacher formation, pedagogical agency, pedagogical interaction, social justice, hidden curriculum

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485 Prevention and Treatment of Hay Fever Prevalence by Natural Products: A Phytochemistry Study on India and Iran

Authors: Tina Naser Torabi

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Prevalence of allergy is affected by different factors according to its base and seasonal weather changes, and it also needs various treatments.Although reasons of allergy existence are not clear but generally, allergens cause reaction between antigen and antibody because of their antigenic traits. In this state, allergens cause immune system to make mistake and identify safe material as threat, therefore function of immune system impaired because of histamine secretion. There are different reasons for allergy, but herbal reasons are on top of the list, although animal causes cannot be ignored. Important point is that allergenic compounds, cause making dedicated antibody, so in general every kind of allergy is different from the other one. Therefore, most of the plants in herbal allergenic category can cause various allergies for human beings, such as respiratory allergies, nutritional allergies, injection allergies, infection allergies, touch allergies, that each of them show different symptoms based on the reason of allergy and also each of them requires different prevention and treatment. Geographical condition is another effective factor in allergy. Seasonal changes, weather condition, herbal coverage variety play important roles in different allergies. It goes without saying that humid climate and herbal coverage variety in different seasons especially spring cause most allergies in human beings in Iran and India that are discussed in this article. These two countries are good choices for allergy prevalence because of their condition, various herbal coverage, human and animal factors. Hay fever is one of the allergies, although the reasons of its prevalence are unknown yet. It is one of the most popular allergies in Iran and India because of geographical, human, animal and herbal factors. Hay fever is on top of the list in these two countries. Significant point about these two countries is that herbal factor is the most important factor in prevalence of hay fever. Variety of herbal coverage especially in spring during herbal pollination is the main reason of hay fever prevalence in these two countries. Based on the research result of Pharmacognosy and Phytochemistry, pollination of some plants in spring is major reason of hay fever prevalence in these countries. If airborne pollens in pollination season enter the human body through air, they will cause allergic reactions in eyes, nasal mucosa, lungs, and respiratory system, and if these particles enter the body of potential person through food, they will cause allergic reactions in mouth, stomach, and other digestive systems. Occasionally, chemical materials produced by human body such as Histamine cause problems like: developing of nasal polyps, nasal blockage, sleep disturbance, risk of asthma developing, blood vasodilation, sneezing, eye tears, itching and swelling of eyes and nasal mucosa, Urticaria, decrease in blood pressure, and rarely trauma, anesthesia, anaphylaxis and finally death. This article is going to study the reasons of hay fever prevalence in Iran and India and presents prevention and treatment Method from Phytochemistry and Pharmocognocy point of view by using local natural products in these two countries.

Keywords: hay fever, India, Iran, natural treatment, phytochemistry

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484 Unveiling Microbial Potential: Investigating Zinc-Solubilizing Fungi in Rhizospheric Soil Through Isolation, Characterization and Selection

Authors: Pukhrambam Helena Chanu, Janardan Yadav

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This study investigates the potential of various fungal isolates to solubilize zinc and counteract rice pathogens, with the aim of mitigating zinc deficiency and disease prevalence in rice farming. Soil samples from the rhizosphere were collected, and zinc-solubilizing fungi were isolated and purified. Molecular analysis identified Talaromyces sp, Talaromyces versatilis, Talaromyces pinophilus, and Aspergillus terreus as effective zinc solubilizers. Through qualitative and quantitative assessments, it was observed that solubilization efficiencies varied among the isolates over time, with Talaromyces versatilis displaying the highest capacity for solubilization. This variability in solubilization rates may be attributed to differences in fungal metabolic activity and their ability to produce organic acids that facilitate zinc release from insoluble sources in the soil. In inhibition assays against rice pathogens, the fungal isolates exhibited antagonistic properties, with Talaromyces versatilis demonstrating the most significant inhibition rates. This antagonistic activity may be linked to the production of secondary metabolites, such as antibiotics or lytic enzymes by fungi, which inhibit the growth of rice pathogens. The ability of Talaromyces versatilis to outperform other isolates in both zinc solubilization and pathogen inhibition highlights its potential as a multifunctional biocontrol agent in rice cultivation systems. These findings emphasize the potential of fungi as natural solutions for enhancing zinc uptake and managing diseases in rice cultivation. Utilizing indigenous zinc-solubilizing fungi offers a sustainable and environmentally friendly approach to addressing zinc deficiency in soils, reducing the need for chemical fertilizers. Moreover, harnessing the antagonistic activity of these fungi can contribute to integrated disease management strategies, minimizing reliance on synthetic pesticides and promoting ecological balance in agroecosystems. Additionally, the study included the evaluation of dipping time under different concentrations, viz.,10 ppm, 20 ppm, and 30 ppm of biosynthesized nano ZnO on rice seedlings. This investigation aimed to optimize the application of nano ZnO for efficient zinc uptake by rice plants while minimizing potential risks associated with excessive nanoparticle exposure. Evaluating the effects of varying concentrations and dipping durations provides valuable insights into the safe and effective utilization of nano ZnO as a micronutrient supplement in rice farming practices.

Keywords: biosynthesized nano ZnO, rice, root dipping, zinc solubilizing fungi.

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483 Sweet to Bitter Perception Parageusia: Case of Posterior Inferior Cerebellar Artery Territory Diaschisis

Authors: I. S. Gandhi, D. N. Patel, M. Johnson, A. R. Hirsch

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Although distortion of taste perception following a cerebrovascular event may seem to be a frivolous consequence of a classic stroke presentation, altered taste perception places patients at an increased risk for malnutrition, weight loss, and depression, all of which negatively impact the quality of life. Impaired taste perception can result from a wide variety of cerebrovascular lesions to various locations, including pons, insular cortices, and ventral posteromedial nucleus of the thalamus. Wallenberg syndrome, also known as a lateral medullary syndrome, has been described to impact taste; however, specific sweet to bitter taste dysgeusia from a territory infarction is an infrequent event; as such, a case is presented. One year prior to presentation, this 64-year-old right-handed woman, suffered a right posterior inferior cerebellar artery aneurysm rupture with resultant infarction, culminating in a ventriculoperitoneal shunt placement. One and half months after this event, she noticed the gradual onset of lack of ability to taste sweet, to eventually all sweet food tasting bitter. Since the onset of her chemosensory problems, the patient has lost 60-pounds. Upon gustatory testing, the patient's taste threshold showed ageusia to sucrose and hydrochloric acid, while normogeusia to sodium chloride, urea, and phenylthiocarbamide. The gustatory cortex is made in part by the right insular cortex as well as the right anterior operculum, which are primarily involved in the sensory taste modalities. In this model, sweet is localized in the posterior-most along with the rostral aspect of the right insular cortex, notably adjacent to the region responsible for bitter taste. The sweet to bitter dysgeusia in our patient suggests the presence of a lesion in this localization. Although the primary lesion in this patient was located in the right medulla of the brainstem, neurodegeneration in the rostal and posterior-most aspect, of the right insular cortex may have occurred due to diaschisis. Diaschisis has been described as neurophysiological changes that occur in remote regions to a focal brain lesion. Although hydrocephalus and vasospasm due to aneurysmal rupture may explain the distal foci of impairment, the gradual onset of dysgeusia is more indicative of diaschisis. The perception of sweet, now tasting bitter, suggests that in the absence of sweet taste reception, the intrinsic bitter taste of food is now being stimulated rather than sweet. In the evaluation and treatment of taste parageusia secondary to cerebrovascular injury, prophylactic neuroprotective measures may be worthwhile. Further investigation is warranted.

Keywords: diaschisis, dysgeusia, stroke, taste

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482 Fischer Tropsch Synthesis in Compressed Carbon Dioxide with Integrated Recycle

Authors: Kanchan Mondal, Adam Sims, Madhav Soti, Jitendra Gautam, David Carron

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Fischer-Tropsch (FT) synthesis is a complex series of heterogeneous reactions between CO and H2 molecules (present in the syngas) on the surface of an active catalyst (Co, Fe, Ru, Ni, etc.) to produce gaseous, liquid, and waxy hydrocarbons. This product is composed of paraffins, olefins, and oxygenated compounds. The key challenge in applying the Fischer-Tropsch process to produce transportation fuels is to make the capital and production costs economically feasible relative to the comparative cost of existing petroleum resources. To meet this challenge, it is imperative to enhance the CO conversion while maximizing carbon selectivity towards the desired liquid hydrocarbon ranges (i.e. reduction in CH4 and CO2 selectivities) at high throughputs. At the same time, it is equally essential to increase the catalyst robustness and longevity without sacrificing catalyst activity. This paper focuses on process development to achieve the above. The paper describes the influence of operating parameters on Fischer Tropsch synthesis (FTS) from coal derived syngas in supercritical carbon dioxide (ScCO2). In addition, the unreacted gas and solvent recycle was incorporated and the effect of unreacted feed recycle was evaluated. It was expected that with the recycle, the feed rate can be increased. The increase in conversion and liquid selectivity accompanied by the production of narrower carbon number distribution in the product suggest that higher flow rates can and should be used when incorporating exit gas recycle. It was observed that this process was capable of enhancing the hydrocarbon selectivity (nearly 98 % CO conversion), reducing improving the carbon efficiency from 17 % to 51 % in a once through process and further converting 16 % CO2 to liquid with integrated recycle of the product gas stream and increasing the life of the catalyst. Catalyst robustness enhancement has been attributed to the absorption of heat of reaction by the compressed CO2 which reduced the formation of hotspots and the dissolution of waxes by the CO2 solvent which reduced the blinding of active sites. In addition, the recycling the product gas stream reduced the reactor footprint to one-fourth of the once through size and product fractionation utilizing the solvent effects of supercritical CO2 were realized. In addition to the negative CO2 selectivities, methane production was also inhibited and was limited to less than 1.5%. The effect of the process conditions on the life of the catalysts will also be presented. Fe based catalysts are known to have a high proclivity for producing CO2 during FTS. The data of the product spectrum and selectivity on Co and Fe-Co based catalysts as well as those obtained from commercial sources will also be presented. The measurable decision criteria were the increase in CO conversion at H2:CO ratio of 1:1 (as commonly found in coal gasification product stream) in supercritical phase as compared to gas phase reaction, decrease in CO2 and CH4 selectivity, overall liquid product distribution, and finally an increase in the life of the catalysts.

Keywords: carbon efficiency, Fischer Tropsch synthesis, low GHG, pressure tunable fractionation

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481 Association between Maternal Personality and Postnatal Mother-to-Infant Bonding

Authors: Tessa Sellis, Marike A. Wierda, Elke Tichelman, Mirjam T. Van Lohuizen, Marjolein Berger, François Schellevis, Claudi Bockting, Lilian Peters, Huib Burger

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Introduction: Most women develop a healthy bond with their children, however, adequate mother-to-infant bonding cannot be taken for granted. Mother-to-infant bonding refers to the feelings and emotions experienced by the mother towards her child. It is an ongoing process that starts during pregnancy and develops during the first year postpartum and likely throughout early childhood. The prevalence of inadequate bonding ranges from 7 to 11% in the first weeks postpartum. An impaired mother-to-infant bond can cause long-term complications for both mother and child. Very little research has been conducted on the direct relationship between the personality of the mother and mother-to-infant bonding. This study explores the associations between maternal personality and postnatal mother-to-infant bonding. The main hypothesis is that there is a relationship between neuroticism and mother-to-infant bonding. Methods: Data for this study were used from the Pregnancy Anxiety and Depression Study (2010-2014), which examined symptoms of and risk factors for anxiety or depression during pregnancy and the first year postpartum of 6220 pregnant women who received primary, secondary or tertiary care in the Netherlands. The study was expanded in 2015 to investigate postnatal mother-to-infant bonding. For the current research 3836 participants were included. During the first trimester of gestation, baseline characteristics, as well as personality, were measured through online questionnaires. Personality was measured by the NEO Five Factor Inventory (NEO-FFI), which covers the big five of personality (neuroticism, extraversion, openness, altruism and conscientiousness). Mother-to-infant bonding was measured postpartum by the Postpartum Bonding Questionnaire (PBQ). Univariate linear regression analysis was performed to estimate the associations. Results: 5% of the PBQ-respondents reported impaired bonding. A statistically significant association was found between neuroticism and mother-to-infant bonding (p < .001): mothers scoring higher on neuroticism, reported a lower score on mother-to-infant bonding. In addition, a positive correlation was found between the personality traits extraversion (b: -.081), openness (b: -.014), altruism (b: -.067), conscientiousness (b: -.060) and mother-to-infant bonding. Discussion: This study is one of the first to demonstrate a direct association between the personality of the mother and mother-to-infant bonding. A statistically significant relationship has been found between neuroticism and mother-to-infant bonding, however, the percentage of variance predictable by a personality dimension is very small. This study has examined one part of the multi-factorial topic of mother-to-infant bonding and offers more insight into the rarely investigated and complex matter of mother-to-infant bonding. For midwives, it is important recognize the risks for impaired bonding and subsequently improve policy for women at risk.

Keywords: mother-to-infant bonding, personality, postpartum, pregnancy

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480 Food Strategies in the Mediterranean Basin, Possible for Food Safety and Security

Authors: Lorenza Sganzetta, Nunzia Borrelli

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The research intends to reflect on the current mapping of the Food Strategies, on the reasons why in the planning objectives panorama, such sustainability priorities are located in those geographic areas and on the evolutions of these priorities of the Mediterranean planning dispositions. The whirling population growth that is affecting global cities is causing an enormous challenge to conventional resource-intensive food production and supply and the urgent need to face food safety, food security and sustainability concerns. Urban or Territorial Food Strategies can provide an interesting path for the development of this new agenda within the imperative principle of sustainability. In the specific, it is relevant to explore what ‘sustainability’ means within these policies. Most of these plans include actions related to four main components and interpretations of sustainability that are food security and safety, food equity, environmental sustainability itself and cultural identity and, at the designing phase, they differ slightly from each other according to the degree of approximation to one of these dimensions. Moving from these assumptions, the article would analyze some practices and policies representatives of different Food Strategies of the world and focus on the Mediterranean ones, on the problems and negative externalities from which they start, on the first interventions that are implementing and on their main objectives. We will mainly use qualitative data from primary and secondary collections. So far, an essential observation could have been made about the relationship between these sustainability dimensions and geography. In statistical terms, the US and Canadian policies tended to devote a large research space to health issues and access to food; those northern European showed a special attention to the environmental issues and the shortening of the chain; and finally the policies that, even in limited numbers, were being developed in the Mediterranean basin, were characterized by a strong territorial and cultural imprint and their major aim was to preserve local production and the contact between the productive land and the end consumer. Recently, though, Mediterranean food planning strategies are focusing more on health related and food accessibility issues and analyzing our diets not just as a matter of culture and territorial branding but as tools for reducing public health costs and accessibility to fresh food for everyone. The article would reflect then on how Food Safety, Food Security and Health are entering the new agenda of the Mediterranean Food Strategies. The research hypothesis suggests that the economic crisis that in the last years invested both producers and consumers had a significant impact on the nutrition habits and on the redefinition of food poverty, even in the fatherland of the healthy Mediterranean diet. This trend and other variables influenced the orientation and the objectives of the food strategies.

Keywords: food security, food strategy, health, sustainability

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479 Dynamics of Hepatitis B Infection Prevention Practices among Pregnant Women Attending Antenatal Care in Central Uganda Using the Constructs of Information-Motivation-Behavioral Skills Model: A Case of Lubaga Hospital Kampala

Authors: Ismail Bamidele Afolabi, Abdulmujeeb Babatunde Aremu, Lawal Abdurraheem Maidoki, Nnodimele Onuigbo Atulomah

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Background: Hepatitis B virus infection remains a significant global public health challenge with infectivity as well as the potential for transmission more than 50 to 100 times that of HIV. Annually, global HBV-related mortality is linked primarily to cirrhosis and liver carcinoma. The ever-increasing endemicity of HBV among children under-5-years, owing to vertical transmission and its lingering chronicity in developing countries, will hamper the global efforts concertedly endorsed towards eliminating viral hepatitis as a global public health threat by 2030. Objective: This study assessed information motivation behavioral skills model constructs as predictors of HBV infection prevention practices among consenting expectant mothers attending antenatal care in Central Uganda as a focal point of intervention towards breaking materno-foetal transmission of HBV. Methods: A cross-sectional study with a quantitative data collection approach based on the constructs of the IMB model was used to capture data on the study variables among 385 randomly selected pregnant women between September and October 2020. Data derived from the quantitative instrument were transformed into weighted aggregate scores using SPSS version 26. ANOVA and regression analysis were done to ascertain the study hypotheses with a significance level set as (p ≤ 0.05). Results: Relatively 60% of the respondents were aged between 18 and 28. Expectant mothers with secondary education (42.3%) were predominant. Furthermore, an average but inadequate knowledge (X ̅=5.97±6.61; B=0.57; p<.001), incorrect perception (X ̅=17.10±18.31; B=0.97; p=.014), and good behavioral skills (X ̅=12.39±13.37; B=0.56; p<.001) for adopting prevention practices all statistically predicted the unsatisfactory level of prevention practices (X ̅=15.03±16.20) among the study respondents as measured on rating scales of 12, 33, 21 and 30 respectively. Conclusion: Evidence from this study corroborates the imperativeness of IMB constructs in reducing the burden of HBV infection in developing countries. Therefore, the inadequate HBV knowledge and misperception among obstetric populations necessitate personalized health education during antenatal visits and subsequent health campaigns in order to inform better prevention practices and, in turn, reduce the lingering chronicity of HBV infection in developing countries.

Keywords: behavioral skills, HBV infection, knowledge, perception, pregnant women, prevention practices

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478 Redefining Success Beyond Borders: A Deep Dive into Effective Methods to Boost Morale Among Virtual Workers for Exponential Project Performance

Authors: Florence Ibeh, David Oyewmi Oyekunle, David Boohene

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The continuous advancement of information technology has completely transformed how businesses and organizations operate on a global scale. The widespread availability of virtual communication tools enables individuals to opt for remote work. While remote employment offers various benefits, such as facilitating corporate growth and enhancing customer support, it also presents distinct challenges. Therefore, investigating the intricacies of virtual team morale is crucial for ensuring the achievement of project objectives. For this study, content analysis of pre-existing secondary data was employed to examine the phenomenon. Essential elements vital for improving the success of projects within virtual teams were identified. These factors include technology adoption, creating a distraction-free work environment, effective leadership, trust-building, clear communication channels, well-defined task allocation, active team participation, and motivation. Furthermore, the study established a substantial correlation between morale levels and the participation and productivity of virtual team members. Higher levels of morale were associated with optimal performance among virtual teams. The study determined that the key factors for enhancing project performance in virtual teams are the adoption of technology, a focused environment, effective leadership, trust, communication, well-defined tasks, collaborative teamwork, and motivation. Additionally, the study discovered that modifying the optimal strategies employed by in-office teams can enhance the diminished morale prevalent in remote teams to sustain a high level of team morale for virtual teams. The findings of this study are highly significant in the dynamic field of project management. Currently, there is limited information regarding strategies that address challenges arising from external factors in virtual teams, such as ambient noise and disruptions caused by family members. The findings underscore the significance of selecting appropriate communication technologies, delineating distinct roles and responsibilities for virtual team members, and nurturing a culture of accountability and trust. Promoting seamless collaboration and instilling motivation among virtual team members are deemed highly effective in augmenting employee engagement and performance within virtual team setting.

Keywords: virtual teams, morale, project performance, distract-free environment, technology adaptation

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477 Role of Community Youths in Conservation of Forests and Protected Areas of Bangladesh

Authors: Obaidul Fattah Tanvir, Zinat Ara Afroze

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Community living adjacent to forests and Protected Areas, especially in South Asian countries, have a common practice in extracting resources for their living and livelihoods. This extraction of resources, because the way it is done, destroys the biophysical features of the area. Deforestation, wildlife poaching, illegal logging, unauthorized hill cutting etc. are some of the serious issues of concern for the sustainability of the natural resources that has a direct impact on environment and climate as a whole. To ensure community involvement in conservation initiatives of the state, community based forest management, commonly known as Comanagement, has been in practice in 6 South Asian countries. These are -India, Nepal, Sri Lanka, Pakistan, Bhutan and Bangladesh. Involving community in forestry management was initiated first in Bangladesh in 1979 and reached as an effective co-management approach through a several paradigm shifts. This idea of Comanagement has been institutionalized through a Government Order (GO) by the Ministry of Environment and Forests, Government of Bangladesh on November 23, 2009. This GO clearly defines the structure and functions of Co-management and its different bodies. Bangladesh Forest Department has been working in association with community to conserve and manage the Forests and Protected areas of Bangladesh following this legal document. Demographically young people constitute the largest segment of population in Bangladesh. This group, if properly sensitized, can produce valuable impacts on the conservation initiatives, both by community and government. This study traced the major factors that motivate community youths to work effectively with different tiers of comanagement organizations in conservation of forests and Protected Areas of Bangladesh. For the purpose of this study, 3 FGDs were conducted with 30 youths from the community living around the Protected Areas of Cox’s bazar, South East corner of Bangladesh, who are actively involved in Co-management organizations. KII were conducted with 5 key officials of Forest Department stationed at Cox’s Bazar. 2 FGDs were conducted with the representatives of 7 Co-management organizations working in Cox’s Bazar region and approaches of different community outreach activities conducted for forest conservation by 3 private organizations and Projects have been reviewed. Also secondary literatures were reviewed for the history and evolution of Co-management in Bangladesh and six South Asian countries. This study found that innovative community outreach activities that are financed by public and private sectors involving youths and community as a whole have played a pivotal role in conservation of forests and Protected Areas of the region. This approach can be replicated in other regions of Bangladesh as well as other countries of South Asia where Co-Management exists in practice.

Keywords: community, co-management, conservation, forests, protected areas, youth

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476 Solutions of Thickening the Sludge from the Wastewater Treatment by a Rotor with Bars

Authors: Victorita Radulescu

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Introduction: The sewage treatment plants, in the second stage, are formed by tanks having as main purpose the formation of the suspensions with high possible solid concentration values. The paper presents a solution to produce a rapid concentration of the slurry and sludge, having as main purpose the minimization as much as possible the size of the tanks. The solution is based on a rotor with bars, tested into two different areas of industrial activity: the remediation of the wastewater from the oil industry and, in the last year, into the mining industry. Basic Methods: It was designed, realized and tested a thickening system with vertical bars that manages to reduce sludge moisture content from 94% to 87%. The design was based on the hypothesis that the streamlines of the vortices detached from the rotor with vertical bars accelerate, under certain conditions, the sludge thickening. It is moved at the lateral sides, and in time, it became sediment. The formed vortices with the vertical axis in the viscous fluid, under the action of the lift, drag, weight, and inertia forces participate at a rapid aggregation of the particles thus accelerating the sludge concentration. Appears an interdependence between the Re number attached to the flow with vortex induced by the vertical bars and the size of the hydraulic compaction phenomenon, resulting from an accelerated process of sedimentation, therefore, a sludge thickening depending on the physic-chemical characteristics of the resulting sludge is projected the rotor's dimensions. Major findings/ Results: Based on the experimental measurements was performed the numerical simulation of the hydraulic rotor, as to assure the necessary vortices. The experimental measurements were performed to determine the optimal height and the density of the bars for the sludge thickening system, to assure the tanks dimensions as small as possible. The time thickening/settling was reduced by 24% compared to the conventional used systems. In the present, the thickeners intend to decrease the intermediate stage of water treatment, using primary and secondary settling; but they assume a quite long time, the order of 10-15 hours. By using this system, there are no intermediary steps; the thickening is done automatically when are created the vortices. Conclusions: The experimental tests were carried out in the wastewater treatment plant of the Refinery of oil from Brazi, near the city Ploiesti. The results prove its efficiency in reducing the time for compacting the sludge and the smaller humidity of the evacuated sediments. The utilization of this equipment is now extended and it is tested the mining industry, with significant results, in Lupeni mine, from the Jiu Valley.

Keywords: experimental tests, hydrodynamic modeling, rotor efficiency, wastewater treatment

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475 Spatial Direct Numerical Simulation of Instability Waves in Hypersonic Boundary Layers

Authors: Jayahar Sivasubramanian

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Understanding laminar-turbulent transition process in hyper-sonic boundary layers is crucial for designing viable high speed flight vehicles. The study of transition becomes particularly important in the high speed regime due to the effect of transition on aerodynamic performance and heat transfer. However, even after many years of research, the transition process in hyper-sonic boundary layers is still not understood. This lack of understanding of the physics of the transition process is a major impediment to the development of reliable transition prediction methods. Towards this end, spatial Direct Numerical Simulations are conducted to investigate the instability waves generated by a localized disturbance in a hyper-sonic flat plate boundary layer. In order to model a natural transition scenario, the boundary layer was forced by a short duration (localized) pulse through a hole on the surface of the flat plate. The pulse disturbance developed into a three-dimensional instability wave packet which consisted of a wide range of disturbance frequencies and wave numbers. First, the linear development of the wave packet was studied by forcing the flow with low amplitude (0.001% of the free-stream velocity). The dominant waves within the resulting wave packet were identified as two-dimensional second mode disturbance waves. Hence the wall-pressure disturbance spectrum exhibited a maximum at the span wise mode number k = 0. The spectrum broadened in downstream direction and the lower frequency first mode oblique waves were also identified in the spectrum. However, the peak amplitude remained at k = 0 which shifted to lower frequencies in the downstream direction. In order to investigate the nonlinear transition regime, the flow was forced with a higher amplitude disturbance (5% of the free-stream velocity). The developing wave packet grows linearly at first before reaching the nonlinear regime. The wall pressure disturbance spectrum confirmed that the wave packet developed linearly at first. The response of the flow to the high amplitude pulse disturbance indicated the presence of a fundamental resonance mechanism. Lower amplitude secondary peaks were also identified in the disturbance wave spectrum at approximately half the frequency of the high amplitude frequency band, which would be an indication of a sub-harmonic resonance mechanism. The disturbance spectrum indicates, however, that fundamental resonance is much stronger than sub-harmonic resonance.

Keywords: boundary layer, DNS, hyper sonic flow, instability waves, wave packet

Procedia PDF Downloads 164
474 Rhizobium leguminosarum: Selecting Strain and Exploring Delivery Systems for White Clover

Authors: Laura Villamizar, David Wright, Claudia Baena, Marie Foxwell, Maureen O'Callaghan

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Leguminous crops can be self-sufficient for their nitrogen requirements when their roots are nodulated with an effective Rhizobium strain and for this reason seed or soil inoculation is practiced worldwide to ensure nodulation and nitrogen fixation in grain and forage legumes. The most widely used method of applying commercially available inoculants is using peat cultures which are coated onto seeds prior to sowing. In general, rhizobia survive well in peat, but some species die rapidly after inoculation onto seeds. The development of improved formulation methodology is essential to achieve extended persistence of rhizobia on seeds, and improved efficacy. Formulations could be solid or liquid. Most popular solid formulations or delivery systems are: wettable powders (WP), water dispersible granules (WG), and granules (DG). Liquid formulation generally are: suspension concentrates (SC) or emulsifiable concentrates (EC). In New Zealand, R. leguminosarum bv. trifolii strain TA1 has been used as a commercial inoculant for white clover over wide areas for many years. Seeds inoculation is carried out by mixing the seeds with inoculated peat, some adherents and lime, but rhizobial populations on stored seeds decline over several weeks due to a number of factors including desiccation and antibacterial compounds produced by the seeds. In order to develop a more stable and suitable delivery system to incorporate rhizobia in pastures, two strains of R. leguminosarum (TA1 and CC275e) and several formulations and processes were explored (peat granules, self-sticky peat for seed coating, emulsions and a powder containing spray dried microcapsules). Emulsions prepared with fresh broth of strain TA1 were very unstable under storage and after seed inoculation. Formulations where inoculated peat was used as the active ingredient were significantly more stable than those prepared with fresh broth. The strain CC275e was more tolerant to stress conditions generated during formulation and seed storage. Peat granules and peat inoculated seeds using strain CC275e maintained an acceptable loading of 108 CFU/g of granules or 105 CFU/g of seeds respectively, during six months of storage at room temperature. Strain CC275e inoculated on peat was also microencapsulated with a natural biopolymer by spray drying and after optimizing operational conditions, microparticles containing 107 CFU/g and a mean particle size between 10 and 30 micrometers were obtained. Survival of rhizobia during storage of the microcapsules is being assessed. The development of a stable product depends on selecting an active ingredient (microorganism), robust enough to tolerate some adverse conditions generated during formulation, storage, and commercialization and after its use in the field. However, the design and development of an adequate formulation, using compatible ingredients, optimization of the formulation process and selecting the appropriate delivery system, is possibly the best tool to overcome the poor survival of rhizobia and provide farmers with better quality inoculants to use.

Keywords: formulation, Rhizobium leguminosarum, storage stability, white clover

Procedia PDF Downloads 134
473 CO2 Utilization by Reverse Water-Shift and Fischer-Tropsch Synthesis for Production of Heavier Fraction Hydrocarbons in a Container-Sized Mobile Unit

Authors: Francisco Vidal Vázquez, Pekka Simell, Christian Frilund, Matti Reinikainen, Ilkka Hiltunen, Tim Böltken, Benjamin Andris, Paolo Piermartini

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Carbon capture and utilization (CCU) are one of the key topics in mitigation of CO2 emissions. There are many different technologies that are applied for the production of diverse chemicals from CO2 such as synthetic natural gas, Fischer-Tropsch products, methanol and polymers. Power-to-Gas and Power-to-Liquids concepts arise as a synergetic solution for storing energy and producing value added products from the intermittent renewable energy sources and CCU. VTT is a research and technology development company having energy in transition as one of the key focus areas. VTT has extensive experience in piloting and upscaling of new energy and chemical processes. Recently, VTT has developed and commissioned a Mobile Synthesis Unit (MOBSU) in close collaboration with INERATEC, a spin-off company of Karlsruhe Institute of Technology (KIT, Germany). The MOBSU is a multipurpose synthesis unit for CO2 upgrading to energy carriers and chemicals, which can be transported on-site where CO2 emission and renewable energy are available. The MOBSU is initially used for production of fuel compounds and chemical intermediates by combination of two consecutive processes: reverse Water-Gas Shift (rWGS) and Fischer-Tropsch synthesis (FT). First, CO2 is converted to CO by high-pressure rWGS and then, the CO and H2 rich effluent is used as feed for FT using an intensified reactor technology developed and designed by INERATEC. Chemical equilibrium of rWGS reaction is not affected by pressure. Nevertheless, compression would be required in between rWGS and FT in the case when rWGS is operated at atmospheric pressure. This would also require cooling of rWGS effluent, water removal and reheating. For that reason, rWGS is operated using precious metal catalyst in the MOBSU at similar pressure as FT to simplify the process. However, operating rWGS at high pressures has also some disadvantages such as methane and carbon formation, and more demanding specifications for materials. The main parts of FT module are an intensified reactor, a hot trap to condense the FT wax products, and a cold trap to condense the FT liquid products. The FT synthesis is performed using cobalt catalyst in a novel compact reactor technology with integrated highly-efficient water evaporation cooling cycle. The MOBSU started operation in November 2016. First, the FT module is tested using as feedstock H2 and CO. Subsequently, rWGS and FT modules are operated together using CO2 and H2 as feedstock of ca. 5 Nm3/hr total flowrate. On spring 2017, The MOBSU unit will be integrated together with a direct air capture (DAC) of CO2 unit, and a PEM electrolyser unit at Lappeenranta University of Technology (LUT) premises for demonstration of the SoletAir concept. This would be the first time when synthetic fuels are produced by combination of DAC unit and electrolyser unit which uses solar power for H2 production.

Keywords: CO2 utilization, demonstration, Fischer-Tropsch synthesis, intensified reactors, reverse water-gas shift

Procedia PDF Downloads 272
472 Computer Based Identification of Possible Molecular Targets for Induction of Drug Resistance Reversion in Multidrug Resistant Mycobacterium Tuberculosis

Authors: Oleg Reva, Ilya Korotetskiy, Marina Lankina, Murat Kulmanov, Aleksandr Ilin

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Molecular docking approaches are widely used for design of new antibiotics and modeling of antibacterial activities of numerous ligands which bind specifically to active centers of indispensable enzymes and/or key signaling proteins of pathogens. Widespread drug resistance among pathogenic microorganisms calls for development of new antibiotics specifically targeting important metabolic and information pathways. A generally recognized problem is that almost all molecular targets have been identified already and it is getting more and more difficult to design innovative antibacterial compounds to combat the drug resistance. A promising way to overcome the drug resistance problem is an induction of reversion of drug resistance by supplementary medicines to improve the efficacy of the conventional antibiotics. In contrast to well established computer-based drug design, modeling of drug resistance reversion still is in its infancy. In this work, we proposed an approach to identification of compensatory genetic variants reducing the fitness cost associated with the acquisition of drug resistance by pathogenic bacteria. The approach was based on an analysis of the population genetic of Mycobacterium tuberculosis and on results of experimental modeling of the drug resistance reversion induced by a new anti-tuberculosis drug FS-1. The latter drug is an iodine-containing nanomolecular complex that passed clinical trials and was admitted as a new medicine against MDR-TB in Kazakhstan. Isolates of M. tuberculosis obtained on different stages of the clinical trials and also from laboratory animals infected with MDR-TB strain were characterized by antibiotic resistance, and their genomes were sequenced by the paired-end Illumina HiSeq 2000 technology. A steady increase in sensitivity to conventional anti-tuberculosis antibiotics in series of isolated treated with FS-1 was registered despite the fact that the canonical drug resistance mutations identified in the genomes of these isolates remained intact. It was hypothesized that the drug resistance phenotype in M. tuberculosis requires an adjustment of activities of many genes to compensate the fitness cost of the drug resistance mutations. FS-1 cased an aggravation of the fitness cost and removal of the drug-resistant variants of M. tuberculosis from the population. This process caused a significant increase in genetic heterogeneity of the Mtb population that was not observed in the positive and negative controls (infected laboratory animals left untreated and treated solely with the antibiotics). A large-scale search for linkage disequilibrium associations between the drug resistance mutations and genetic variants in other genomic loci allowed identification of target proteins, which could be influenced by supplementary drugs to increase the fitness cost of the drug resistance and deprive the drug-resistant bacterial variants of their competitiveness in the population. The approach will be used to improve the efficacy of FS-1 and also for computer-based design of new drugs to combat drug-resistant infections.

Keywords: complete genome sequencing, computational modeling, drug resistance reversion, Mycobacterium tuberculosis

Procedia PDF Downloads 242
471 Combined Effect of Zinc Supplementation and Ascaridia galli Infection on Oxidative Status in Broiler Chicks

Authors: Veselin Nanev, Margarita Gabrashanska, Neli Tsocheva-Gaytandzieva

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Ascaridiasis in chicks is one of the major causes for the reduction in body weights, higher mortality, and reduction in egg production, worse meat quantity, pathological lesions, blood losses, and secondary infections. It is responsible for economic losses to the poultry. Despite being economically important parasite, little work has been carried out on the role of antioxidants in the pathogenesis of ascaridiasis. Zinc is a trace elements with multiple functions and one of them is its antioxidant ability. The aim of this study was to investigate the combined effect of organic zinc compound (2Gly.ZnCl22H20) and Ascaridia galli infection on the antioxidant status of broiler chicks. The activity of antioxidant enzymes superoxide dismutase, glutathione peroxidase, the level of lipid peroxidation, expressed by malonyl dialdexyde and plasma zinc in chicks experimentally infected with Ascaridia galli was investigated. Parasite burden was studied as well. The study was performed on 80 broiler chicks, Cobb 500 hybrids. They were divided into four groups – 1st group – control (non-treated and non-infected, 2nd group – infected with embryonated eggs of A. galli and without treatment, 3rd group- only treated with 2Gly.ZnCl22H20 compound and gr. 4 - infected and supplemented with Zn-compound. The chicks in gr. 2 and 4 were infected orally with 450 embryonated eggs of A.galli on day 14 post infection. The chicks from gr. 3 and 4 received 40 mg Zn compound /kg of feed after the 1st week of age during 10 days. All chicks were similarly fed, managed and killed at 60 day p.i. Helminthological, biochemical and statistical methods were applied. Reduced plasma Zn content was observed in the infected chicks compared to controls. Zinc supplementation did not restored the lower Zn content. Cu, Zn-SOD was decreased significantly in the infected chicks compared to controls. The GPx – activity was significantly increased in the infected chicks than the controls. Increased GPx activity together with decreased Cu/ZnSOD activity revealed unbalanced antioxidant defense capacity. The increased MDA level in chicks and changes in the activity of the enzymes showed a development of oxidative stress during the infection with A.galli. Zn compound supplementation has been shown to influence the activity of both antioxidant enzymes (SOD, GPx) and reduced MDA in the infected chicks. Organic zinc supplementation improved the antioxidant defense and protect hosts from oxidant destruction, but without any effect on the parasite burden. The number of helminths was similar in both groups. Zn supplementation did not changed the number of parasites. Administration of oral 2Gly.ZnCl22H20 compound has been shown to be useful in chicks infected with A. galli by its improvement of their antioxidant potential.

Keywords: Ascaridia galli, antioxidants, broiler chicks, zinc supplementation

Procedia PDF Downloads 115
470 Investigations of Effective Marketing Metric Strategies: The Case of St. George Brewery Factory, Ethiopia

Authors: Mekdes Getu Chekol, Biniam Tedros Kahsay, Rahwa Berihu Haile

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The main objective of this study is to investigate the marketing strategy practice in the Case of St. George Brewery Factory in Addis Ababa. One of the core activities in a Business Company to stay in business is having a well-developed marketing strategy. It assessed how the marketing strategies were practiced in the company to achieve its goals aligned with segmentation, target market, positioning, and the marketing mix elements to satisfy customer requirements. Using primary and secondary data, the study is conducted by using both qualitative and quantitative approaches. The primary data was collected through open and closed-ended questionnaires. Considering the size of the population is small, the selection of the respondents was carried out by using a census. The finding shows that the company used all the 4 Ps of the marketing mix elements in its marketing strategies and provided quality products at affordable prices by promoting its products by using high and effective advertising mechanisms. The product availability and accessibility are admirable with the practices of both direct and indirect distribution channels. On the other hand, the company has identified its target customers, and the company’s market segmentation practice is geographical location. Communication effectiveness between the marketing department and other departments is very good. The adjusted R2 model explains 61.6% of the marketing strategy practice variance by product, price, promotion, and place. The remaining 38.4% of variation in the dependent variable was explained by other factors not included in this study. The result reveals that all four independent variables, product, price, promotion, and place, have a positive beta sign, proving that predictor variables have a positive effect on that of the predicting dependent variable marketing strategy practice. Even though the marketing strategies of the company are effectively practiced, there are some problems that the company faces while implementing them. These are infrastructure problems, economic problems, intensive competition in the market, shortage of raw materials, seasonality of consumption, socio-cultural problems, and the time and cost of awareness creation for the customers. Finally, the authors suggest that the company better develop a long-range view and try to implement a more structured approach to attain information about potential customers, competitor’s actions, and market intelligence within the industry. In addition, we recommend conducting the study by increasing the sample size and including different marketing factors.

Keywords: marketing strategy, market segmentation, target marketing, market positioning, marketing mix

Procedia PDF Downloads 29
469 Arisarum Vulgare: Bridging Tradition and Science through Phytochemical Characterization and Exploring Therapeutic Potential via in vitro and in vivo Biological Activities

Authors: Boudjelal Amel

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Arisarum vulgare, a member of the Araceae family, is an herbaceous perennial widely distributed in the Mediterranean region. A. vulgare is recognized for its medicinal properties and holds significant traditional importance in Algeria for the treatment of various human ailments, including pain, infections, inflammation, digestive disorders, skin problems, eczema, cancer, wounds, burns and gynecological diseases. Despite its extensive traditional use, scientific exploration of A. vulgare remains limited. The study aims to investigate for the first time the therapeutic potential of A. vulgare ethanolic extract obtained by ultrasound-assisted extraction. The chemical composition of the extract was determined by LC-MS/MS analysis. For in vitro phytopharmacological evaluation, several assays, including DPPH, ABTS, FRAP and reducing power, were employed to evaluate the antioxidant activity. The antibacterial activity was assessed againt Escherichia coli, Salmonella typhimurium, Staphylococus aureus, Enterococcus feacium by disk diffusion and microdilution methods. The possible inhibitory activity of ethanolic extract was analyzed against the cholinesterases enzymes (AChE and BChE). The DNA protection activity of A. vulgare ethanolic extract was estimated using the agarose gel electrophoresis method. The capacities of the extract to protect plasmid DNA (pBR322) from the oxidizing effects of H2O2 and UV treatment were evaluated by their DNA-breaking forms. The in vivo wound healing potential of a traditional ointment containing 5% of A. vulgare ethanolic extract was also investigated. The LC-MS/MS profiling of the extract revealed the presence of various bioactive compounds, including naringenin, chlorogenic, vanillic, cafeic, coumaric acids, trans-cinnamic and trans ferrulic acids. The plant extract presented considerable antioxidant potential, being the most active for Reducing power (0,07326±0.001 mg/ml) and DPPH (0.14±0.004 mg/ml). The extract showed the highest inhibition zone diameter against Enterococcus feacium (36±0.1 mm). The ethanolic extract of A. vulgare suppressed the growth of Staphylococus aureus, Escherichia coli and Salmonella typhimurium according to the MIC values. The extract of the plant significantly inhibited both AChE and BChE enzymes. DNA protection activity of the A. vulgare extract was determined as 90.41% for form I and 51.92% for form II. The in vivo experiments showed that 5% ethanolic extract ointment accelerated the wound healing process. The topical application of the traditional formulation enhanced wound closure (95,36±0,6 %) and improved histological parameters in the treated group compared to the control groups. The promising biological properties of Arisarum vulgare revealed that the plant could be appraised as a potential origin of bioactive molecules having multifunctional medicinal uses.

Keywords: arisarum vulgare, LC-MS/MS, antioxidant activity, antimicrobial activity, cholinesterases enzymes inhibition, dna-damage activity, in vivo wound healing

Procedia PDF Downloads 37
468 Thermoluminescence Investigations of Tl2Ga2Se3S Layered Single Crystals

Authors: Serdar Delice, Mehmet Isik, Nizami Hasanli, Kadir Goksen

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Researchers have donated great interest to ternary and quaternary semiconductor compounds especially with the improvement of the optoelectronic technology. The quaternary compound Tl2Ga2Se3S which was grown by Bridgman method carries the properties of ternary thallium chalcogenides group of semiconductors with layered structure. This compound can be formed from TlGaSe2 crystals replacing the one quarter of selenium atom by sulfur atom. Although Tl2Ga2Se3S crystals are not intentionally doped, some unintended defect types such as point defects, dislocations and stacking faults can occur during growth processes of crystals. These defects can cause undesirable problems in semiconductor materials especially produced for optoelectronic technology. Defects of various types in the semiconductor devices like LEDs and field effect transistor may act as a non-radiative or scattering center in electron transport. Also, quick recombination of holes with electrons without any energy transfer between charge carriers can occur due to the existence of defects. Therefore, the characterization of defects may help the researchers working in this field to produce high quality devices. Thermoluminescence (TL) is an effective experimental method to determine the kinetic parameters of trap centers due to defects in crystals. In this method, the sample is illuminated at low temperature by a light whose energy is bigger than the band gap of studied sample. Thus, charge carriers in the valence band are excited to delocalized band. Then, the charge carriers excited into conduction band are trapped. The trapped charge carriers are released by heating the sample gradually and these carriers then recombine with the opposite carriers at the recombination center. By this way, some luminescence is emitted from the samples. The emitted luminescence is converted to pulses by using an experimental setup controlled by computer program and TL spectrum is obtained. Defect characterization of Tl2Ga2Se3S single crystals has been performed by TL measurements at low temperatures between 10 and 300 K with various heating rate ranging from 0.6 to 1.0 K/s. The TL signal due to the luminescence from trap centers revealed one glow peak having maximum temperature of 36 K. Curve fitting and various heating rate methods were used for the analysis of the glow curve. The activation energy of 13 meV was found by the application of curve fitting method. This practical method established also that the trap center exhibits the characteristics of mixed (general) kinetic order. In addition, various heating rate analysis gave a compatible result (13 meV) with curve fitting as the temperature lag effect was taken into consideration. Since the studied crystals were not intentionally doped, these centers are thought to originate from stacking faults, which are quite possible in Tl2Ga2Se3S due to the weakness of the van der Waals forces between the layers. Distribution of traps was also investigated using an experimental method. A quasi-continuous distribution was attributed to the determined trap centers.

Keywords: chalcogenides, defects, thermoluminescence, trap centers

Procedia PDF Downloads 264
467 Mechanisms Underlying the Effects of School-Based Internet Intervention for Alcohol Drinking Behaviours among Chinese Adolescent

Authors: Keith T. S. Tung, Frederick K. Ho, Rosa S. Wong, Camilla K. M. Lo, Wilfred H. S. Wong, C. B. Chow, Patrick Ip

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Objectives: Underage drinking is an important public health problem both locally and globally. Conventional prevention/intervention relies on unidirectional knowledge transfer such as mail leaflets or health talks which showed mixed results in changing the target behaviour. Previously, we conducted a school internet-based intervention which was found to be effective in reducing alcohol use among adolescents, yet the underlying mechanisms have not been properly investigated. This study, therefore, examined the mechanisms that explain how the intervention produced a change in alcohol drinking behaviours among Chinese adolescent as observed in our previous clustered randomised controlled trial (RCT) study. Methods: This is a cluster randomised controlled trial with parallel group design. Participating schools were randomised to the Internet intervention or the conventional health education group (control) with a 1:1 allocation ratio. Secondary 1–3 students of the participating schools were enrolled in this study. The Internet intervention was a web-based quiz game competition, in which participating students would answer 1,000 alcohol-related multiple-choice quiz questions. Conventional health education group received a promotional package on equivalent alcohol-related knowledge. The participants’ alcohol-related attitude, knowledge, and perceived behavioural control were self-reported before the intervention (baseline) and one month and three months after the intervention. Results: Our RCT results showed that participants in the Internet group were less likely to drink (risk ratio [RR] 0.79, p < 0.01) as well as in lesser amount (β -0.06, p < 0.05) compared to those in the control group at both post-intervention follow-ups. Within the intervention group, regression analyses showed that high quiz scorer had greater improvement in alcohol-related knowledge (β 0.28, p < 0.01) and attitude (β -0.26, p < 0.01) at 1 month after intervention, which in turn increased their perceived behavioural control against alcohol use (β 0.10 and -0.26, both p < 0.01). Attitude, compared to knowledge, was found to be a stronger contributor to the intervention effect on perceived behavioural control. Conclusions: Our internet-based intervention has demonstrated effectiveness in reducing the risk of underage drinking when compared with conventional health education. Our study results further showed an attitude to be a more important factor than knowledge in changing health-related behaviour. This has an important implication for future prevention/intervention on an underage drinking problem.

Keywords: adolescents, internet-based intervention, randomized controlled trial, underage drinking

Procedia PDF Downloads 131
466 Conservative and Surgical Treatment of Antiresorptive Drug-Related Osteonecrosis of the Jaw with Ultrasonic Piezoelectric Bone Surgery under Polyvinylpyrrolidone Iodine Irrigation: A Case Series of 13 Treated Sites

Authors: Esra Yuce, Isil D. S. Yamaner, Murude Yazan

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Aims and objective: Antiresorptive agents including bisphosphonates and denosumab as strong suppressors of osteoclasts are the most commonly used antiresorptive medications for the treatment of osteoporosis which counteract the negative quantitative alteration of trabecular and cortical bone by inhibition of bone turnover. Oral bisphosphonate therapy for the treatment of osteopenia, osteoporosis or Paget's disease is associated with the low-grade risk of osteonecrosis of the jaw, while higher-grade risk is associated with receiving intravenous bisphosphonates therapy in the treatment of multiple myeloma and bone metastases. On the other hand, there has been a remarkable increase in incidences of antiresorptive related osteonecrosis of the jaw (ARONJ) in oral bisphosphonate users. This clinical presentation will evaluate the healing outcomes via piezoelectric bone surgery under the irrigation of PVP-I solution irrigation in patients received bisphosphonate therapy. Material-Method: The study involved 8 female and 5 male patients that have been treated for ARONJ. Among 13 necrotic sites, 9 were in the mandible and 4 were in the maxilla. All of these 13 patients treated with surgical debridement via piezoelectric bone surgery under irrigation by solution with 3% PVP-I concentration in combination with long-term antibiotic therapy and 5 also underwent removal of mobile segments of bony sequestrum. All removable prosthesis in 8 patients were relined with soft liners during the healing periods in order to eliminate chronic minor traumas. Results: All patients were on oral bisphosphonate therapy for at least 2 years and 5 of which had received intravenous bisphosphonates up to 1 year before therapy with oral bisphosphonates was started. According to the AAOMS staging system, four cases were stage II, eight cases were stage I, and one case was stage III. The majority of lesions were identified at sites of dental prostheses (38%) and dental extractions (62%). All patients diagnosed with ARONJ stage I had used unadjusted removable prostheses. No recurrence of the symptoms was observed during the present follow-up (9–37 months). Conclusion: Despite their confirmed effectiveness, the prevention and treatment of osteonecrosis of the jaw secondary to oral bisphosphonate therapy remain major medical challenges. Treatment with piezoelectric bone surgery with irrigation of povidone-iodine solution was effective for management of bisphosphonate-related osteonecrosis of the jaw. Taking precautions for patients treated with oral bisphosphonates, especially also denture users, may allow for a reduction in the rate of developing osteonecrosis of the maxillofacial region.

Keywords: antiresorptive drug related osteonecrosis, bisphosphonate therapy, piezoelectric bone surgery, povidone iodine

Procedia PDF Downloads 243
465 Fermented Fruit and Vegetable Discard as a Source of Feeding Ingredients and Functional Additives

Authors: Jone Ibarruri, Mikel Manso, Marta Cebrián

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A high amount of food is lost or discarded in the World every year. In addition, in the last decades, an increasing demand of new alternative and sustainable sources of proteins and other valuable compounds is being observed in the food and feeding sectors and, therefore, the use of food by-products as nutrients for these purposes sounds very interesting from the environmental and economical point of view. However, the direct use of discarded fruit and vegetables that present, in general, a low protein content is not interesting as feeding ingredient except if they are used as a source of fiber for ruminants. Especially in the case of aquaculture, several alternatives to the use of fish meal and other vegetable protein sources have been extensively explored due to the scarcity of fish stocks and the unsustainability of fishing for these purposes. Fish mortality is also of great concern in this sector as this problem highly reduces their economic feasibility. So, the development of new functional and natural ingredients that could reduce the need for vaccination is also of great interest. In this work, several fermentation tests were developed at lab scale using a selected mixture of fruit and vegetable discards from a wholesale market located in the Basque Country to increase their protein content and also to produce some bioactive extracts that could be used as additives in aquaculture. Fruit and vegetable mixtures (60/40 ww) were centrifugated for humidity reduction and crushed to 2-5 mm particle size. Samples were inoculated with a selected Rhizopus oryzae strain and fermented for 7 days in controlled conditions (humidity between 65 and 75% and 28ºC) in Petri plates (120 mm) by triplicate. Obtained results indicated that the final fermented product presented a twofold protein content (from 13 to 28% d.w). Fermented product was further processed to determine their possible functionality as a feed additive. Extraction tests were carried out to obtain an ethanolic extract (60:40 ethanol: water, v.v) and remaining biomass that also could present applications in food or feed sectors. The extract presented a polyphenol content of about 27 mg GAE/gr d.w with antioxidant activity of 8.4 mg TEAC/g d.w. Remining biomass is mainly composed of fiber (51%), protein (24%) and fat (10%). Extracts also presented antibacterial activity according to the results obtained in Agar Diffusion and to the Minimum Inhibitory Concentration (MIC) tests determined against several food and fish pathogen strains. In vitro, digestibility was also assessed to obtain preliminary information about the expected effect of extraction procedure on fermented product digestibility. First results indicated that remaining biomass after extraction doesn´t seem to improve digestibility in comparison to the initial fermented product. These preliminary results show that fermented fruit and vegetables can be a useful source of functional ingredients for aquaculture applications and a substitute of other protein sources in the feeding sector. Further validation will be also carried out through “in vivo” tests with trout and bass.

Keywords: fungal solid state fermentation, protein increase, functional extracts, feed ingredients

Procedia PDF Downloads 48
464 The Significance of Islamic Concept of Good Faith to Cure Flaws in Public International Law

Authors: M. A. H. Barry

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The concept of Good faith (husn al-niyyah) and fair-dealing (Nadl) are the fundamental guiding elements in all contracts and other agreements under Islamic law. The preaching of Al-Quran and Prophet Muhammad’s (Peace Be upon Him) firmly command people to act in good faith in all dealings. There are several Quran verses and the Prophet’s saying which stressed the significance of dealing honestly and fairly in all transactions. Under the English law, the good faith is not considered a fundamental requirement for the formation of a legal contract. However, the concept of Good Faith in private contracts is recognized by the civil law system and in Article 7(1) of the Convention on International Sale of Goods (CISG-Vienna Convention-1980). It took several centuries for the international trading community to recognize the significance of the concept of good faith for the international sale of goods transactions. Nevertheless, the recognition of good faith in Civil law is only confined for the commercial contracts. Subsequently to the CISG, this concept has made inroads into the private international law. There are submissions in favour of applying the good faith concept to public international law based on tacit recognition by the international conventions and International Tribunals. However, under public international law the concept of good faith is not recognized as a source of rights or obligations. This weakens the spirit of the good faith concept, particularly when determining the international disputes. This also creates a fundamental flaw because the absence of good faith application means the breaches tainted by bad faith are tolerated. The objective of this research is to evaluate, examine and analyze the application of the concept of good faith in the modern laws and identify its limitation, in comparison with Islamic concept of good faith. This paper also identifies the problems and issues connected with the non-application of this concept to public international law. This research consists of three key components (1) the preliminary inquiry (2) subject analysis and discovery of research results, and (3) examining the challenging problems, and concluding with proposals. The preliminary inquiry is based on both the primary and secondary sources. The same sources are used for the subject analysis. This research also has both inductive and deductive features. The Islamic concept of good faith covers all situations and circumstances where the bad faith causes unfairness to the affected parties, especially the weak parties. Under the Islamic law, the concept of good faith is a source of rights and obligations as Islam prohibits any person committing wrongful or delinquent acts in any dealing whether in a private or public life. This rule is applicable not only for individuals but also for institutions, states, and international organizations. This paper explains how the unfairness is caused by non-recognition of the good faith concept as a source of rights or obligations under public international law and provides legal and non-legal reasons to show why the Islamic formulation is important.

Keywords: good faith, the civil law system, the Islamic concept, public international law

Procedia PDF Downloads 117
463 Gut Microbial Dynamics in a Mouse Model of Inflammation-Linked Carcinogenesis as a Result of Diet Supplementation with Specific Mushroom Extracts

Authors: Alvarez M., Chapela M. J., Balboa E., Rubianes D., Sinde E., Fernandez de Ana C., Rodríguez-Blanco A.

Abstract:

The gut microbiota plays an important role as gut inflammation could contribute to colorectal cancer development; however, this role is still not fully understood, and tools able to prevent this progression are yet to be developed. The main objective of this study was to monitor the effects of a mushroom extracts formulation in gut microbial community composition of an Azoxymethane (AOM)/Dextran sodium sulfate (DSS) mice model of inflammation-linked carcinogenesis. For the in vivo study, 41 adult male mice of the C57BL / 6 strain were obtained. 36 of them have been induced in a state of colon carcinogenesis by a single intraperitoneal administration of AOM at a dose of 12.5 mg/kg; the control group animals received instead of the same volume of 0.9% saline. DSS is an extremely toxic polysaccharide sulfate that causes chronic inflammation of the colon mucosa, favoring the appearance of severe colitis and the production of tumors induced by AOM. Induction by AOM/DSS is an interesting platform for chemopreventive intervention studies. This time the model was used to monitor gut microbiota changes as a result of supplementation with a specific mushroom extracts formulation previously shown to have prebiotic activity. The animals have been divided into three groups: (i) Cancer + mushroom extracts formulation experimental group: to which the MicoDigest2.0 mushroom extracts formulation developed by Hifas da Terra S.L has been administered dissolved in drinking water at an estimated concentration of 100 mg / ml. (ii) Control group of animals with Cancer: to which normal water has been administered without any type of treatment. (iii) Control group of healthy animals: these are the animals that have not been induced cancer or have not received any treatment in drinking water. This treatment has been maintained for a period of 3 months, after which the animals were sacrificed to obtain tissues that were subsequently analyzed to verify the effects of the mushroom extract formulation. A microbiological analysis has been carried out to compare the microbial communities present in the intestines of the mice belonging to each of the study groups. For this, the methodology of massive sequencing by molecular analysis of the 16S gene has been used (Ion Torrent technology). Initially, DNA extraction and metagenomics libraries were prepared using the 16S Metagenomics kit, always following the manufacturer's instructions. This kit amplifies 7 of the 9 hypervariable regions of the 16S gene that will then be sequenced. Finally, the data obtained will be compared with a database that makes it possible to determine the degree of similarity of the sequences obtained with a wide range of bacterial genomes. Results obtained showed that, similarly to certain natural compounds preventing colorectal tumorigenesis, a mushroom formulation enriched the Firmicutes and Proteobacteria phyla and depleted Bacteroidetes. Therefore, it was demonstrated that the consumption of the mushroom extracts’ formulation developed could promote the recovery of the microbial balance that is disrupted in the mice model of carcinogenesis. More preclinical and clinical studies are needed to validate this promising approach.

Keywords: carcinogenesis, microbiota, mushroom extracts, inflammation

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462 Folding of β-Structures via the Polarized Structure-Specific Backbone Charge (PSBC) Model

Authors: Yew Mun Yip, Dawei Zhang

Abstract:

Proteins are the biological machinery that executes specific vital functions in every cell of the human body by folding into their 3D structures. When a protein misfolds from its native structure, the machinery will malfunction and lead to misfolding diseases. Although in vitro experiments are able to conclude that the mutations of the amino acid sequence lead to incorrectly folded protein structures, these experiments are unable to decipher the folding process. Therefore, molecular dynamic (MD) simulations are employed to simulate the folding process so that our improved understanding of the folding process will enable us to contemplate better treatments for misfolding diseases. MD simulations make use of force fields to simulate the folding process of peptides. Secondary structures are formed via the hydrogen bonds formed between the backbone atoms (C, O, N, H). It is important that the hydrogen bond energy computed during the MD simulation is accurate in order to direct the folding process to the native structure. Since the atoms involved in a hydrogen bond possess very dissimilar electronegativities, the more electronegative atom will attract greater electron density from the less electronegative atom towards itself. This is known as the polarization effect. Since the polarization effect changes the electron density of the two atoms in close proximity, the atomic charges of the two atoms should also vary based on the strength of the polarization effect. However, the fixed atomic charge scheme in force fields does not account for the polarization effect. In this study, we introduce the polarized structure-specific backbone charge (PSBC) model. The PSBC model accounts for the polarization effect in MD simulation by updating the atomic charges of the backbone hydrogen bond atoms according to equations derived between the amount of charge transferred to the atom and the length of the hydrogen bond, which are calculated from quantum-mechanical calculations. Compared to other polarizable models, the PSBC model does not require quantum-mechanical calculations of the peptide simulated at every time-step of the simulation and maintains the dynamic update of atomic charges, thereby reducing the computational cost and time while accounting for the polarization effect dynamically at the same time. The PSBC model is applied to two different β-peptides, namely the Beta3s/GS peptide, a de novo designed three-stranded β-sheet whose structure is folded in vitro and studied by NMR, and the trpzip peptides, a double-stranded β-sheet where a correlation is found between the type of amino acids that constitute the β-turn and the β-propensity.

Keywords: hydrogen bond, polarization effect, protein folding, PSBC

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461 Phytochemical and Vitamin Composition of Wild Edible Plants Consumed in South West Ethiopia

Authors: Abebe Yimer, Sirawdink Fikereyesus Forsido, Getachew Addis, Abebe Ayelign

Abstract:

Background: Oxidative stress has been an important health problem as itinduceschronic diseases such as cancer, cardiovascular, diabetics, and neurodegenerative disease. Plant source natural antioxidant has gained attention as synthetic antioxidant negatively impact human health. Wild edible plants arecheap source of dietary-medicine in mainly rural communityin south-west Ethiopia and elsewhere the country. Thus, the study aimed to determine total pheneol,flavoinoids, antioxidant, vitamin C, and beta-carotene content from wild edible plants Solanum nigrum L., Vigna membranacea A. Rich, Dioscorea praehensilis Benth., Trilepisium madagascariense D.C.andCleome gynandra L. Methods: Methanol was used to extract samples of oven-dried edible plants. Total phenolic compound (TPC) was determined using a Folin Ciocalteu method, whereas total flavonoid content (TFC) was determined using the Aluminium chloride colorimetric method. By using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) tests, antioxidant activities were evaluated in vitro. Additionally, beta-carotene was assessed using a spectrophotometric technique, whilst vitamin C was determined using a titration approach. Results: Total flavonoid contentranged from 0.85±0.03 to 11.25±0.01 mg CE/g in D. praehensilis Benth. tuber and C. gynandra L, respectively. Total phenolic compounds varied from 0.25±0.06 GAE/g in D. praehensilis Benth tuber to 35.73±2.52 GAE/g in S.nigrum L. leaves. In the DPPH test, the highest antioxidant value (87.65%) was obtained in the S.nigrum L. leaves, whereas the smallest amount of antioxidant (50.12%)was contained in D. praehensilis Benth tuber. Similarly in FRAP assay,D. praehensilis Benth tuber showed the least reducing potential(49.16± 2.13mM Fe2+/100 g)whilst the highest reducing potential was presented in the S.nigrum L. leaves(188.12±1.13 mM Fe2+/100 g). The beta-carotene content was found between 11.81±0.00 mg/100g in D. praehensilis Benth tubers to 34.49±0.95 mg/100g in V. membranacea A. Rich leaves. The concentration of vitamin C ranged from 10.00±0.61 in D. praehensilis Benth tubers to 45±1.80 mg/100g in V. membranacea A. Rich leaves. The results showed that high positive linear correlations between TPC and TFC of WEPs (r=0.828), as well as between FRAP and total phenolic contents (r = 0.943) and FRAP and vitamin C (r= 0.928). Conclusion: These findings showed the total phenolic and flavonoid contents of Solanum nigrum L. and Cleome gynandra L, respectively, are abundant. The outcome may be used as a natural supply of dietary antioxidants, which may be useful in preventing oxidative stress. The study's findings also showed that Vigna membranacea A. Rich leaves were cheap source of vitamin C and beta-carotene for people who consumed these wild green. Additional research on the in vivo antioxidant activity, toxicological analysis, and promotion of these wild food plants for agricultural production should be taken into consideration.

Keywords: antioxidant activity, beta-carotene, flavonoids, phenolic content, and vitamin c

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460 Polymer Composites Containing Gold Nanoparticles for Biomedical Use

Authors: Bozena Tyliszczak, Anna Drabczyk, Sonia Kudlacik-Kramarczyk, Agnieszka Sobczak-Kupiec

Abstract:

Introduction: Nanomaterials become one of the leading materials in the synthesis of various compounds. This is a reason for the fact that nano-size materials exhibit other properties compared to their macroscopic equivalents. Such a change in size is reflected in a change in optical, electric or mechanical properties. Among nanomaterials, particular attention is currently directed into gold nanoparticles. They find application in a wide range of areas including cosmetology or pharmacy. Additionally, nanogold may be a component of modern wound dressings, which antibacterial activity is beneficial in the viewpoint of the wound healing process. Specific properties of this type of nanomaterials result in the fact that they may also be applied in cancer treatment. Studies on the development of new techniques of the delivery of drugs are currently an important research subject of many scientists. This is due to the fact that along with the development of such fields of science as medicine or pharmacy, the need for better and more effective methods of administering drugs is constantly growing. The solution may be the use of drug carriers. These are materials that combine with the active substance and lead it directly to the desired place. A role of such a carrier may be played by gold nanoparticles that are able to covalently bond with many organic substances. This allows the combination of nanoparticles with active substances. Therefore gold nanoparticles are widely used in the preparation of nanocomposites that may be used for medical purposes with special emphasis on drug delivery. Methodology: As part of the presented research, synthesis of composites was carried out. The mentioned composites consisted of the polymer matrix and gold nanoparticles that were introduced into the polymer network. The synthesis was conducted with the use of a crosslinking agent, and photoinitiator and the materials were obtained by means of the photopolymerization process. Next, incubation studies were conducted using selected liquids that simulated fluids are occurring in the human body. The study allows determining the biocompatibility of the tested composites in relation to selected environments. Next, the chemical structure of the composites was characterized as well as their sorption properties. Conclusions: Conducted research allowed for the preliminary characterization of prepared polymer composites containing gold nanoparticles in the viewpoint of their application for biomedical use. Tested materials were characterized by biocompatibility in tested environments. What is more, synthesized composites exhibited relatively high swelling capacity that is essential in the viewpoint of their potential application as drug carriers. During such an application, composite swells and at the same time releases from its interior introduced active substance; therefore, it is important to check the swelling ability of such material. Acknowledgements: The authors would like to thank The National Science Centre (Grant no: UMO - 2016/21/D/ST8/01697) for providing financial support to this project. This paper is based upon work from COST Action (CA18113), supported by COST (European Cooperation in Science and Technology).

Keywords: nanocomposites, gold nanoparticles, drug carriers, swelling properties

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459 Well-Defined Polypeptides: Synthesis and Selective Attachment of Poly(ethylene glycol) Functionalities

Authors: Cristina Lavilla, Andreas Heise

Abstract:

The synthesis of sequence-controlled polymers has received increasing attention in the last years. Well-defined polyacrylates, polyacrylamides and styrene-maleimide copolymers have been synthesized by sequential or kinetic addition of comonomers. However this approach has not yet been introduced to the synthesis of polypeptides, which are in fact polymers developed by nature in a sequence-controlled way. Polypeptides are natural materials that possess the ability to self-assemble into complex and highly ordered structures. Their folding and properties arise from precisely controlled sequences and compositions in their constituent amino acid monomers. So far, solid-phase peptide synthesis is the only technique that allows preparing short peptide sequences with excellent sequence control, but also requires extensive protection/deprotection steps and it is a difficult technique to scale-up. A new strategy towards sequence control in the synthesis of polypeptides is introduced, based on the sequential addition of α-amino acid-N-carboxyanhydrides (NCAs). The living ring-opening process is conducted to full conversion and no purification or deprotection is needed before addition of a new amino acid. The length of every block is predefined by the NCA:initiator ratio in every step. This method yields polypeptides with a specific sequence and controlled molecular weights. A series of polypeptides with varying block sequences have been synthesized with the aim to identify structure-property relationships. All of them are able to adopt secondary structures similar to natural polypeptides, and display properties in the solid state and in solution that are characteristic of the primary structure. By design the prepared polypeptides allow selective modification of individual block sequences, which has been exploited to introduce functionalities in defined positions along the polypeptide chain. Poly(ethylene glycol)(PEG) was the functionality chosen, as it is known to favor hydrophilicity and also yield thermoresponsive materials. After PEGylation, hydrophilicity of the polypeptides is enhanced, and their thermal response in H2O has been studied. Noteworthy differences in the behavior of the polypeptides having different sequences have been found. Circular dichroism measurements confirmed that the α-helical conformation is stable over the examined temperature range (5-90 °C). It is concluded that PEG units are the main responsible of the changes in H-bonding interactions with H2O upon variation of temperature, and the position of these functional units along the backbone is a factor of utmost importance in the resulting properties of the α-helical polypeptides.

Keywords: α-amino acid N-carboxyanhydrides, multiblock copolymers, poly(ethylene glycol), polypeptides, ring-opening polymerization, sequence control

Procedia PDF Downloads 177