Search results for: prophylactic preparation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1601

Search results for: prophylactic preparation

1331 Polymer Matrices Based on Natural Compounds: Synthesis and Characterization

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

Abstract:

Introduction: In the preparation of polymer materials, compounds of natural origin are currently gaining more and more interest. This is particularly noticeable in the case of synthesis of materials considered for biomedical use. Then, selected material has to meet many requirements. It should be characterized by non-toxicity, biodegradability and biocompatibility. Therefore special attention is directed to substances such as polysaccharides, proteins or substances that are the basic building components of proteins, i.e. amino acids. These compounds may be crosslinked with other reagents that leads to the preparation of polymer matrices. Such amino acids as e.g. cysteine or histidine. On the other hand, previously mentioned requirements may be met by polymers obtained as a result of biosynthesis, e.g. polyhydroxybutyrate. This polymer belongs to the group of aliphatic polyesters that is synthesized by microorganisms (selected strain of bacteria) under specific conditions. It is possible to modify matrices based on given polymer with substances of various origin. Such a modification may result in the change of their properties or/and in providing the material with new features desirable in viewpoint of specific application. Described materials are synthesized using UV radiation. Process of photopolymerization is fast, waste-free and enables to obtain final products with favorable properties. Methodology: Polymer matrices have been prepared by means of photopolymerization. First step involved the preparation of solutions of particular reagents and mixing them in the appropriate ratio. Next, crosslinking agent and photoinitiator have been added to the reaction mixture and the whole was poured into the Petri dish and treated with UV radiation. After the synthesis, polymer samples were dried at room temperature and subjected to the numerous analyses aimed at the determining their physicochemical properties. Firstly, sorption properties of obtained polymer matrices have been determined. Next, mechanical properties have been characterized, i.e. tensile strength. The ability to deformation under applied stress of all prepared polymer matrices has been checked. Such a property is important in viewpoint of the application of analyzed materials e.g. as wound dressings. Wound dressings have to be elastic because depending on the location of the wound and its mobility, such a dressing has to adhere properly to the wound. Furthermore, considering the use of the materials for biomedical purposes it is essential to determine its behavior in environments simulating these ones occurring in human body. Therefore incubation studies using selected liquids have also been conducted. Conclusions: As a result of photopolymerization process, polymer matrices based on natural compounds have been prepared. These exhibited favorable mechanical properties and swelling ability. Moreover, biocompatibility in relation to simulated body fluids has been stated. Therefore it can be concluded that analyzed polymer matrices constitute an interesting materials that may be considered for biomedical use and may be subjected to the further more advanced analyses using specific cell lines.

Keywords: photopolymerization, polymer matrices, simulated body fluids, swelling properties

Procedia PDF Downloads 99
1330 Reviewing Special Education Preservice Teachers' Reflective Practices over Two Field Experiences: Topics and Changes in Reflection

Authors: Laurie U. deBettencourt

Abstract:

During pre-service field experiences teacher candidates are often asked to reflect as part of their training and in this investigation candidates’ reflective journal entries were reviewed, coded and analyzed with results suggesting teacher candidates need more direct instruction on how to describe, analyze, and make judgements on their instructional practices so that their practices improve over time. Teacher education programs often incorporate reflective-based activities during field experiences. The purpose of this investigation was to determine if special education teacher candidate’s reflective practices changed as they completed their two supervised field experiences and to determine what topics the candidates focused on in their reflections. The six females graduate students were completing two field experiences in special education classrooms within one academic year as part of their coursework leading to a master’s degree and special education teacher state certification. Each candidate wrote 15 reflection journal entries (approximately 200 words each) per field experience. Each of the journal entries were reviewed sentence by sentence to determine a reflective practice score and to determine the topics discussed. The reflective practice score was calculated using four dimensions of reflection (describe, analyze, judge, and apply) in order to create a continuous variable representing their reflective practice across four points of time. A One-way Repeated Measures Analysis of Variance (ANOVA) suggested that special education teacher candidates did not change their reflective practices over time (i.e., at time-point one the practitioner’s mean score was 56.0 out of 100 (SD = 7.6), 53.8 (SD = 4.3) at time-point two, 51.2 (SD = 4.5) at time-point three, and 57.7 (SD = 8.2) at time-point four). Qualitative findings suggest candidates focused mostly on themselves in their reflections. Conclusions suggest the need for teacher preparation programs to provide more direct instruction on how a teacher should reflect. Specific implications are provided for teacher training and future research.

Keywords: field experiences, reflective practices, special educators, teacher preparation

Procedia PDF Downloads 325
1329 The Influence of Bacteriocins Producing Lactic Acid Bacteria Multiplied in an Alternative Substrate on Calves Blood Parameters

Authors: E. Bartkiene, V. Krungleviciute, J. Kucinskiene, R. Antanaitis, A. Kucinskas

Abstract:

In calves less than 10-day-old, infection commonly cause severe diarrhoea and high mortality. To prevention of calves diseases a common practice is to treat calves with prophylactic antibiotics, in this case the use of lactic acid bacteria (LAB) is promising. Often LAB strains are incubated in comercial de Man-Rogosa-Sharpe (MRS) medium, the culture are centrifuged, the cells are washing with sterile water, and this suspension is used as a starter culture for animal health care. Juice of potatoe tubers is industrial wastes, wich may constitute a source of digestible nutrients for microorganisms. In our study the ability of LAB to utilize potatoe tubers juice in cell synthesis without external nutrient supplement was investigated, and the influence of multiplied LAB on calves blood parameters was evaluated. Calves were selected based on the analogy principle (treatment group (n=6), control group (n=8)). For the treatment group 14 days was given a 50 ml of fermented potatoe tubers juice containing 9.6 log10 cfu/ml of LAB. Blood parameters (gas and biochemical) were assessed by use of an auto-analyzers (Hitachi 705 and EPOC). Before the experiment, blood pH of treatment group calves was 7.33, control – 7.36, whereas, after 14 days, 7.28 and 7.36, respectively. Calves blood pH in the treatment group remained stable over the all experiment period. Concentration of PCO2 in control calves group blood increased from 63.95 to 70.93, whereas, in the treatment group decreased from 63.08 to 60.71. Concentration of lactate in the treatment group decreased from 3.20 mmol/l to 2.64 mmol/l, whereas, in control - increased from 3.95 mmol/l to 4.29 mmol/l. Concentration of AST in the control calves group increased from 50.18 IU/L to 58.9 IU/L, whereas, in treatment group decreased from 49.82 IU/L to 33.1 IU/L. We conclude that the 50 ml of fermented potatoe tubers juice containing 9.6 log10 cfu/ml of LAB per day, by using 14 days, reduced risk of developing acidosis (stabilizes blood pH (p < 0.05)), reduces lactates and PCO2 concentration (p < 0.05) and risk of liver lesions (reduces AST concentration (p < 0.005)) in blood of calves.

Keywords: alternative substrate, blood parameters, calves, lactic acid bacteria

Procedia PDF Downloads 284
1328 Fabrication of Ligand Coated Lipid-Based Nanoparticles for Synergistic Treatment of Autoimmune Disease

Authors: Asiya Mahtab, Sushama Talegaonkar

Abstract:

The research is aimed at developing targeted lipid-based nanocarrier systems of chondroitin sulfate (CS) to deliver an antirheumatic drug to the inflammatory site in arthritic paw. Lipid-based nanoparticle (TEF-lipo) was prepared by using a thin-film hydration method. The coating of prepared drug-loaded nanoparticles was done by the ionic interaction mechanism. TEF-lipo and CS-coated lipid nanoparticle (CS-lipo) were characterized for mean droplet size, zeta potential, and surface morphology. TEF-lipo and CS-lipo were further subjected to in vitro cell line studies on RAW 264.7 murine macrophage, U937, and MG 63 cell lines. The pharmacodynamic study was performed to establish the effectiveness of the prepared lipid-based conventional and targeted nanoparticles in comparison to pure drugs. Droplet size and zeta potential of TEF-lipo were found to be 128. 92 ± 5.42 nm and +12.6 ± 1.2 mV. It was observed that after the coating of TEF-lipo with CS, particle size increased to 155.6± 2.12 nm and zeta potential changed to -10.2± 1.4mV. Transmission electron microscopic analysis revealed that the nanovesicles were uniformly dispersed and detached from each other. Formulations followed sustained release pattern up to 24 h. Results of cell line studies ind icated that CS-lipo formulation showed the highest cytotoxic potential, thereby proving its enhanced ability to kill the RAW 264.7 murine macrophage and U937 cells when compared with other formulations. It is clear from our in vivo pharmacodynamic results that targeted nanocarriers had a higher inhibitory effect on arthritis progression than nontargeted nanocarriers or free drugs. Results demonstrate that this approach will provide effective treatment for rheumatoid arthritis, and CS served as a potential prophylactic against the advancement of cartilage degeneration.

Keywords: adjuvant induced arthritis, chondroitin sulfate, rheumatoid arthritis, teriflunomide

Procedia PDF Downloads 106
1327 Challenges of Management of Subaortic Membrane in a Young Adult Patient: A Case Review and Literature Review

Authors: Talal Asif, Maya Kosinska, Lucas Georger, Krish Sardesai, Muhammad Shah Miran

Abstract:

This article presents a case review and literature review focused on the challenges of managing subaortic membranes (SAM) in young adult patients with mild aortic regurgitation (AR) or aortic stenosis (AS). The study aims to discuss the diagnosis of SAM, imaging studies used for assessment, management strategies in young patients, the risk of valvular damage, and the controversy surrounding prophylactic resection in mild AR. The management of SAM in adults poses challenges due to limited treatment options and potential complications, necessitating further investigation into the progression of AS and AR in asymptomatic SAM patients. The case presentation describes a 40-year-old male with muscular dystrophy who presented with symptoms and was diagnosed with SAM. Various imaging techniques, including CT chest, transthoracic echocardiogram (TTE), and transesophageal echocardiogram (TEE), were used to confirm the presence and severity of SAM. Based on the patient's clinical profile and the absence of surgical indications, medical therapy was initiated, and regular outpatient follow-up was recommended to monitor disease progression. The discussion highlights the challenges in diagnosing SAM, the importance of imaging studies, and the potential complications associated with SAM in young patients. The article also explores the management options for SAM, emphasizing surgical resection as the definitive treatment while acknowledging the limited success rates of alternative approaches. Close monitoring and prompt intervention for complications are crucial in the management of SAM. The concluding statement emphasizes the need for further research to explore alternative treatments for SAM in young patients.

Keywords: subaortic membrane, management, case report, literature review, aortic regurgitation, aortic stenosis, left ventricular outflow obstruction, guidelines, heart failure

Procedia PDF Downloads 63
1326 Designing of Oat Drink with Phytonutrients Assigned for Pro-Health Oriented Consumers

Authors: Gramza-Michalowska Anna, Skrety Joanna, Anna Zywica, Kobus-Cisowska Joanna, Kmiecik Dominik, Korczak Jozef

Abstract:

Background: Modern consumer highly appreciates the positive influence of consumed products on well-being and overall health. High acceptance of new food is a result of intensified research showing many proofs confirming that food offers significant prophylactic and therapeutic potential, next to its basic nutritional function. Objective: Proposition of the technology of unsweetened oat drinks enriched with plant extracts for pro-health oriented individuals. We investigated the effects of selected plant extracts addition on antioxidative capacity and consumer’s acceptance of drinks as representative of all day diet product. Methods: The analysis of the basic composition and antioxidant properties of the drinking product was conducted. Basic composition included protein, lipids and fiber content. Antioxidant capacity of drink was evaluated with use radical scavenging methods (DPPH, ABTS), ORAC value and FRAP. Proposed drink as new product was also characterized with sensory analysis, which included color, aroma, taste, consistency and overall acceptance. Results: Results showed that addition of plant extracts into a oat drink allowed to enhance its antioxidant potential and influenced significantly its sensory values. The preferred composition and properties of designed beverage permit claim that it can have a positive impact on the health of the consumers. Conclusion: Designed oat drink would be an answer for pro-healthy life style of the consumers. Results showed that product with plant extracts addition would be accepted by the consumers and because of its antioxidative potential could be an important factor in prevention of free radicals influence on human organism.

Keywords: phytonutrients, pro-health, well-being, antioxidant potential, sensory value

Procedia PDF Downloads 311
1325 Characterisation of Chitooligomers Prepared with the Aid of Cellulase, Xylanase and Chitosanase

Authors: Anna Zimoch-Korzycka, Dominika Kulig, Andrzej Jarmoluk

Abstract:

The aim of this study was to obtain chitooligosaccharides from chitosan with better functional properties using three different enzyme preparations and compare the products of enzymatic hydrolysis. Commercially available cellulase (CL), xylanase (X) and chitosanase (CS) preparations were used to investigate hydrolytic activity on chitosan (CH) with low molecular weight and DD of 75-85%. It has been reported that CL and X have side activities of other enzymes, such as β-glucanase or β-glucosidase. CS enzyme has a foreign activity of chitinase. Each preparation was used in 1000 U of activity and in the same reaction conditions. The degree of deacetylation and molecular weight of chitosan were specified using titration and viscometric methods, respectively. The hydrolytic activity of enzymes preparations on chitosan was monitored by dynamic viscosity measurement. After 4 h reaction with stirring, solutions were filtered and chitosan oligomers were isolated by methanol solution into two fractions: precipitate (A) and supernatant (B). A Fourier-transform infrared spectroscopy was used to characterize the structural changes of chitosan oligomers fractions and initial chitosan. Furthermore, the solubility of lyophilized hydrolytic mixture (C) and two chitooligomers fractions (A, B) of each enzyme hydrolysis was assayed. The antioxidant activity of chitosan oligomers was evaluated as DPPH free radical scavenging activity. The dynamic viscosity measured after addition of enzymes preparation to the chitosan solution decreased dramatically over time in the sample with X in comparison to solution without the enzyme. For mixtures with CL and CS, lower viscosities were also recorded but not as low as the ones with X. A and B fractions were characterized by the most similar viscosity obtained by the xylanase hydrolysis and were 15 mPas and 9 mPas, respectively. Structural changes of chitosan oligomers A, B, C and their differences related with various enzyme preparations used were confirmed. Water solubility of A fractions was not possible to filter and the result was not recorded. Solubility of supernatants was approximately 95% and was higher than hydrolytic mixture. It was observed that the DPPH radical scavenging effect of A, B, C samples is the highest for X products and was approximately 13, 17, 19% respectively. In summary, a mixture of chitooligomers may be useful for the design of edible protective coatings due to the improved biophysical properties.

Keywords: cellulase, xylanase, chitosanase, chitosan, chitooligosaccharides

Procedia PDF Downloads 296
1324 Selection and Preparation of High Performance, Natural and Cost-Effective Hydrogel as a Bio-Ink for 3D Bio-Printing and Organ on Chip Applications

Authors: Rawan Ashraf, Ahmed E. Gomaa, Gehan Safwat, Ayman Diab

Abstract:

Background: Three-dimensional (3D) bio-printing has become a versatile and powerful method for generating a variety of biological constructs, including bone or extracellular matrix scaffolds endo- or epithelial, muscle tissue, as well as organoids. Aim of the study: Fabricate a low cost DIY 3D bio-printer to produce 3D bio-printed products such as anti-microbial packaging or multi-organs on chips. We demonstrate the alignment between two types of 3D printer technology (3D Bio-printer and DLP) on Multi-organ-on-a-chip (multi-OoC) devices fabrication. Methods: First, Design and Fabrication of the Syringe Unit for Modification of an Off-the-Shelf 3D Printer, then Preparation of Hydrogel based on natural polymers Sodium Alginate and Gelatin, followed by acquisition of the cell suspension, then modeling the desired 3D structure. Preparation for 3D printing, then Cell-free and cell-laden hydrogels went through the printing process at room temperature under sterile conditions and finally post printing curing process and studying the printed structure regards physical and chemical characteristics. The hard scaffold of the Organ on chip devices was designed and fabricated using the DLP-3D printer, following similar approaches as the Microfluidics system fabrication. Results: The fabricated Bio-Ink was based onHydrogel polymer mix of sodium alginate and gelatin 15% to 0.5%, respectively. Later the 3D printing process was conducted using a higher percentage of alginate-based hydrogels because of it viscosity and the controllable crosslinking, unlike the thermal crosslinking of Gelatin. The hydrogels were colored to simulate the representation of two types of cells. The adaption of the hard scaffold, whether for the Microfluidics system or the hard-tissues, has been acquired by the DLP 3D printers with fabricated natural bioactive essential oils that contain antimicrobial activity, followed by printing in Situ three complex layers of soft-hydrogel as a cell-free Bio-Ink to simulate the real-life tissue engineering process. The final product was a proof of concept for a rapid 3D cell culturing approaches that uses an engineered hard scaffold along with soft-tissues, thus, several applications were offered as products of the current prototype, including the Organ-On-Chip as a successful integration between DLP and 3D bioprinter. Conclusion: Multiple designs for the organ-on-a-chip (multi-OoC) devices have been acquired in our study with main focus on the low cost fabrication of such technology and the potential to revolutionize human health research and development. We describe circumstances in which multi-organ models are useful after briefly examining the requirement for full multi-organ models with a systemic component. Following that, we took a look at the current multi-OoC platforms, such as integrated body-on-a-chip devices and modular techniques that use linked organ-specific modules.

Keywords: 3d bio-printer, hydrogel, multi-organ on chip, bio-inks

Procedia PDF Downloads 129
1323 University-home Partnerships for Enhancing Students’ Career Adapting Responses: A Moderated-mediation Model

Authors: Yin Ma, Xun Wang, Kelsey Austin

Abstract:

Purpose – Building upon career construction theory and the conservation of resources theory, we developed a moderated mediation model to examine how the perceived university support impact students’ career adapting responses, namely, crystallization, exploration, decision and preparation, via the mediator career adaptability and moderator perceived parental support. Design/methodology/approach – The multi-stage sampling strategy was employed and survey data were collected. Structural equation modeling was used to perform the analysis. Findings – Perceived university support could directly promote students’ career adaptability, and promote three career adapting responses, namely, exploration, decision and preparation. It could also impact four career adapting responses via mediation effect of career adaptability. Its impact on students’ career adaptability can greatly increase when students’ receive parental related career support. Research limitations/implications – The cross-sectional design limits causal inference. Conducted in China, our findings should be cautiously interpreted in other countries due to cultural differences. Practical implications – University support is vital to students’ career adaptability and supports from parents can enhance this process. University-home collaboration is necessary to promote students’ career adapting responses. For students, seeking and utilizing as much supporting resources as possible is vital for their human resources development. On an organizational level, universities could benefit from our findings by introducing the practices which ask students to rate the career-related courses and encourage them to chat with parents regularly. Originality/ value – Using recently developed scale, current work contributes to the literature by investigating the impact of multiple contextual factors on students’ career adapting response. It also provide the empirical support for the role of human intervention in fostering career adapting responses.

Keywords: career adapability, university and parental support, China studies, sociology of education

Procedia PDF Downloads 27
1322 Synthesis and Characterization of the Carbon Spheres Built Up from Reduced Graphene Oxide

Authors: Takahiro Saida, Takahiro Kogiso, Takahiro Maruyama

Abstract:

The ordered structural carbon (OSC) material is expected to apply to the electrode of secondary batteries, the catalyst supports, and the biomaterials because it shows the low substance-diffusion resistance by its uniform pore size. In general, the OSC material is synthesized using the template material. Changing size and shape of this template provides the pore size of OSC material according to the purpose. Depositing the oxide nanosheets on the polymer sphere template by the layer by layer (LbL) method was reported as one of the preparation methods of OSC material. The LbL method can provide the controlling thickness of structural wall without the surface modification. When the preparation of the uniform carbon sphere prepared by the LbL method which composed of the graphene oxide wall and the polymethyl-methacrylate (PMMA) core, the reduction treatment will be the important object. Since the graphene oxide has poor electron conductivity due to forming a lot of functional groups on the surface, it could be hard to apply to the electrode of secondary batteries and the catalyst support of fuel cells. In this study, the graphene oxide wall of carbon sphere was reduced by the thermal treatment under the vacuum conditions, and its crystalline structure and electronic state were characterized. Scanning electron microscope images of the carbon sphere after the heat treatment at 300ºC showed maintaining sphere shape, but its shape was collapsed with increasing the heating temperature. In this time, the dissolution rate of PMMA core and the reduction rate of graphene oxide were proportionate to heating temperature. In contrast, extending the heating time was conducive to the conservation of the sphere shape. From results of X-ray photoelectron spectroscopy analysis, its electronic state of the surface was indicated mainly sp² carbon. From the above results, we succeeded in the synthesis of the sphere structure composed by the reduction graphene oxide.

Keywords: carbon sphere, graphene oxide, reduction, layer by layer

Procedia PDF Downloads 118
1321 Disaster Management Approach for Planning an Early Response to Earthquakes in Urban Areas

Authors: Luis Reynaldo Mota-Santiago, Angélica Lozano

Abstract:

Determining appropriate measures to face earthquakesarea challenge for practitioners. In the literature, some analyses consider disaster scenarios, disregarding some important field characteristics. Sometimes, software that allows estimating the number of victims and infrastructure damages is used. Other times historical information of previous events is used, or the scenarios’informationis assumed to be available even if it isnot usual in practice. Humanitarian operations start immediately after an earthquake strikes, and the first hours in relief efforts are important; local efforts are critical to assess the situation and deliver relief supplies to the victims. A preparation action is prepositioning stockpiles, most of them at central warehouses placed away from damage-prone areas, which requires large size facilities and budget. Usually, decisions in the first 12 hours (standard relief time (SRT)) after the disaster are the location of temporary depots and the design of distribution paths. The motivation for this research was the delay in the reaction time of the early relief efforts generating the late arrival of aid to some areas after the Mexico City 7.1 magnitude earthquake in 2017. Hence, a preparation approach for planning the immediate response to earthquake disasters is proposed, intended for local governments, considering their capabilities for planning and for responding during the SRT, in order to reduce the start-up time of immediate response operations in urban areas. The first steps are the generation and analysis of disaster scenarios, which allow estimatethe relief demand before and in the early hours after an earthquake. The scenarios can be based on historical data and/or the seismic hazard analysis of an Atlas of Natural Hazards and Risk as a way to address the limited or null available information.The following steps include the decision processes for: a) locating local depots (places to prepositioning stockpiles)and aid-giving facilities at closer places as possible to risk areas; and b) designing the vehicle paths for aid distribution (from local depots to the aid-giving facilities), which can be used at the beginning of the response actions. This approach allows speeding up the delivery of aid in the early moments of the emergency, which could reduce the suffering of the victims allowing additional time to integrate a broader and more streamlined response (according to new information)from national and international organizations into these efforts. The proposed approachis applied to two case studies in Mexico City. These areas were affectedby the 2017’s earthquake, having limited aid response. The approach generates disaster scenarios in an easy way and plans a faster early response with a short quantity of stockpiles which can be managed in the early hours of the emergency by local governments. Considering long-term storage, the estimated quantities of stockpiles require a limited budget to maintain and a small storage space. These stockpiles are useful also to address a different kind of emergencies in the area.

Keywords: disaster logistics, early response, generation of disaster scenarios, preparation phase

Procedia PDF Downloads 89
1320 Leadership Values in Succession Processes

Authors: Peter Heimerl, Alexander Plaikner, Mike Peters

Abstract:

Background and Significance of the Study: Family-run businesses are a decisive economic factor in the Alpine tourism and leisure industry. Within the next years, it is expected that a large number of family-run small and medium-sized businesses will transfer ownership due to demographic developments. Four stages of succession processes can be identified by several empirical studies: (1) the preparation phase, (2) the succession planning phase, (3) the development of the succession concept, (4) and the implementation of the business transfer. Family business research underlines the importance of individual's and family’s values: Especially leadership values address mainly the first phase, which strongly determines the following stages. Aim of the Study: The study aims at answering the following research question: Which leadership values are dominating during succession processes in family-run businesses in Austrian Alpine tourism industry? Methodology: Twenty-two problem-centred individual interviews with 11 transferors and their 11 transferees were conducted. Data analysis was carried out using the software program MAXQDA following an inductive approach to data coding. Major Findings: Data analysis shows that nine values particularly influence succession processes, especially during the vulnerable preparation phase. Participation is the most-dominant value (162 references). It covers a style of cooperation, communication, and controlling. Discipline (142) is especially prevailing from the transferor's perspective. It addresses entrepreneurial honesty and customer orientation. Development (138) is seen as an important value, but it can be distinguished between transferors and transferees. These are mainly focused on strategic positioning and new technologies. Trust (105) is interpreted as a basic prerequisite to run the family firm smoothly. Interviewees underline the importance to be able to take a break from family-business management; however, this is only possible when openness and honesty constitute trust within the family firm. Loyalty (102): Almost all interviewees perceive that they can influence the loyalty of the employees through their own role models. A good work-life balance (90) is very important to most of the transferors, especially for their employees. Despite the communicated importance of a good work-life-balance, but however, mostly the commitment to the company is prioritised. Considerations of regionality (82) and regional responsibility are also frequently raised. Appreciation (75) is of great importance to both the handover and the takeover generation -as appreciation towards the employees in the company and especially in connection with the family. Familiarity (66) and the blurring of the boundaries between private and professional life are very common, especially in family businesses. Familial contact and open communication with employees which is mentioned in almost all handing over. Conclusions: In the preparation phase of succession, successors and incumbents have to consider and discuss their leadership and family values of family-business management. Quite often, assistance is needed to commonly and openly discuss these values in the early stages of succession processes. A large majority of handovers fail because of these values. Implications can be drawn to support family businesses, e.g., consulting initiatives at chambers of commerce and business consultancies must address this problem.

Keywords: leadership values, family business, succession processes, succession phases

Procedia PDF Downloads 64
1319 Examining E-learning Capability in Chinese Higher Education: A Case Study of Hong Kong

Authors: Elson Szeto

Abstract:

Over the past 15 years, digital technology has ubiquitously penetrated societies around the world. New values of e-learning are emerging in the preparation of future talents, while e-learning is a key driver of widening participation and knowledge transfer in Chinese higher education. As a vibrant, Chinese society in Asia, Hong Kong’s new generation university students, perhaps the digital natives, have been learning with e-learning since their basic education. They can acquire new knowledge with the use of different forms of e-learning as a generic competence. These students who embrace this competence further their study journeys in higher education. This project reviews the Government’s policy of Information Technology in Education which has largely put forward since 1998. So far, primary to secondary education has embraced advantages of e-learning capability to advance the learning of different subject knowledge. Yet, e-learning capacity in higher education is yet to be fully examined in Hong Kong. The study reported in this paper is a pilot investigation into e-learning capacity in Chinese higher education in the region. By conducting a qualitative case study of Hong Kong, the investigation focuses on (1) the institutional ICT settings in general; (2) the pedagogic responses to e-learning in specific; and (3) the university students’ satisfaction of e-learning. It is imperative to revisit the e-learning capacity for promoting effective learning amongst university students, supporting new knowledge acquisition and embracing new opportunities in the 21st century. As a pilot case study, data will be collected from individual interviews with the e-learning management team members of a university, teachers who use e-learning for teaching and students who attend courses comprised of e-learning components. The findings show the e-learning capacity of the university and the key components of leveraging e-learning capability as a university-wide learning settings. The findings will inform institutions’ senior management, enabling them to effectively enhance institutional e-learning capacity for effective learning and teaching and new knowledge acquisition. Policymakers will be aware of new potentials of e-learning for the preparation of future talents in this society at large.

Keywords: capability, e-learning, higher education, student learning

Procedia PDF Downloads 246
1318 Application of WHO's Guideline to Evaluating Apps for Smoking Cessation

Authors: Suin Seo, Sung-Il Cho

Abstract:

Background: The use of mobile apps for smoking cessation has grown exponentially in recent years. Yet, there were limited researches which evaluated the quality of smoking cessation apps to our knowledge. In most cases, a clinical practice guideline which is focused on clinical physician was used as an evaluation tool. Objective: The objective of this study was to develop a user-centered measure for quality of mobile smoking cessation apps. Methods: A literature search was conducted to identify articles containing explicit smoking cessation guideline for smoker published until January 2018. WHO’s guide for tobacco users to quit was adopted for evaluation tool which assesses smoker-oriented contents of smoking cessation apps. Compared to the clinical practice guideline, WHO guideline was designed for smokers (non-specialist). On the basis of existing criteria which was developed based on 2008 clinical practice guideline for Treating Tobacco Use and Dependence, evaluation tool was modified and developed by an expert panel. Results: There were five broad categories of criteria that were identified including five objective quality scales: enhancing motivation, assistance with a planning and making quit attempts, preparation for relapse, self-efficacy, connection to smoking. Enhancing motivation and assistance with planning and making quit attempts were similar to contents of clinical practice guideline, but preparation for relapse, self-efficacy and connection to smoking (environment or habit which reminds of smoking) only existed on WHO guideline. WHO guideline had more user-centered elements than clinical guideline. Especially, self-efficacy is the most important determinant of behavior change in accordance with many health behavior change models. With the WHO guideline, it is now possible to analyze the content of the app in the light of a health participant, not a provider. Conclusion: The WHO guideline evaluation tool is a simple, reliable and smoker-centered tool for assessing the quality of mobile smoking cessation apps. It can also be used to provide a checklist for the development of new high-quality smoking cessation apps.

Keywords: smoking cessation, evaluation, mobile application, WHO, guideline

Procedia PDF Downloads 165
1317 Central Retinal Venous Occlusion Associated O Bilateral Optic Nerve Infiltration Revealing Relapse Of An Acute Lymphoblastic Leukemia

Authors: Fendouli Ines, Zaafrane Nesrine, Mhamdi Hana, Knani Leila, Ghorbel Mohamed

Abstract:

Introduction: Ocular infiltration of leukemia can involve orbit, uveal tract, retina and optic nerve. It may result from direct ocular infiltration by leukemic cells or indirect ocular involvement resulting from secondary hematologic changes, opportunistic infections and complications of various modalities of therapy. We here in report a case of central venous retinal occlusion associated to optic nerve infiltration as presenting signs of a relapse of acute lymphoblastic leukemia. Case Report: A twelve-year-old male -patient of acute B lymphoblastic leukemia presented with headaches and bilateral blurred vision in the left ee. Ophthalmic examination showed a visual acuity reduced to counting fingers in the right eye and no light perception in the left eye. Funduscopy revealed a voluminous disc edema surrounded by retinal haemorrhages in the right eye, and venous tortusities, papillary edema, and hemorrages suggesting central retinal venous occlusion in the LE. Swept source optical coherence tomography revealed a serous retinal detachment in the RE and .hyperreflective inner layers with macular edema in the left eye. Cerebro-orbital MRI showed bilateral thickened left optic nerve. There were no radiological signs of true papillary edema due to intracranial hypertension secondary to central nervous system involvement. Myelogram and lumbar punction demonstrated blast infiltration and confirmed ocular relapse of the leukemia. Conclusion: Ocular involvement lymphoblastic acute leukemias decreased since the introduction of a systematic prophylactic treatment of central nervous system. Periodic ophthalmic examination is necessary to allow early diagnosis and treatment.

Keywords: acute leukemia, optic nerve, infiltration, relapse

Procedia PDF Downloads 55
1316 Preparation of Papers – Inventorship Status For AI - A South African Perspective

Authors: Meshandren Naidoo

Abstract:

An artificial intelligence (AI) system named DABUS 2021 made headlines when it became the very first AI system to be listed in a patent which was then granted by the South African patent office. This grant raised much criticism. The question that this research intends to answer is (1) whether, in South African patent law, an AI can be an inventor. This research finds that despite South African law not recognising an AI as a legal person and despite the legislation not explicitly allowing AI to be inventors, a legal interpretative exercise would allow AI inventorship.

Keywords: artificial intelligence, intellectual property, inventorship, patents

Procedia PDF Downloads 78
1315 Micro-Filtration with an Inorganic Membrane

Authors: Benyamina, Ouldabess, Bensalah

Abstract:

The aim of this study is to use membrane technique for filtration of a coloring solution. the preparation of the micro-filtration membranes is based on a natural clay powder with a low cost, deposited on macro-porous ceramic supports. The micro-filtration membrane provided a very large permeation flow. Indeed, the filtration effectiveness of membrane was proved by the total discoloration of bromothymol blue solution with initial concentration of 10-3 mg/L after the first minutes.

Keywords: the inorganic membrane, micro-filtration, coloring solution, natural clay powder

Procedia PDF Downloads 480
1314 Technical Games Using ICT as a Preparation for Teaching about Technology in Pre-School Age

Authors: Pavlína Částková, Jiří Kropáč, Jan Kubrický

Abstract:

The paper deals with the current issue of Information and Communication Technologies and their implementation into the educational activities of preschool children. The issue is addressed in the context of technical education and the specifics of its implementation in a kindergarten. One of the main topics of this paper is a technical game activity of a preschool child, and its possibilities, benefits and risks. The paper presents games/toys as one of the means of exploring and understanding technology as an essential part of human culture.

Keywords: ICT, technical education, pre-school age, technical games

Procedia PDF Downloads 406
1313 Experimental Study on Thermomechanical Properties of New-Generation ODS Alloys

Authors: O. Khalaj, B. Mašek, H. Jirková, J. Svoboda

Abstract:

By using a combination of new technologies together with an unconventional use of different types of materials, specific mechanical properties and structures of the material can be achieved. Some possibilities are enabled by a combination of powder metallurgy in the preparation of a metal matrix with dispersed stable particles achieved by mechanical alloying and hot consolidation. This paper explains the thermomechanical properties of new generation of Oxide Dispersion Strengthened alloys (ODS) within three ranges of temperature with specified deformation profiles. The results show that the mechanical properties of new ODS alloys are significantly affected by the thermomechanical treatment.

Keywords: hot forming, ODS, alloys, thermomechanical, Fe-Al, Al2O3

Procedia PDF Downloads 246
1312 Preparation and in vivo Assessment of Nystatin-Loaded Solid Lipid Nanoparticles for Topical Delivery against Cutaneous Candidiasis

Authors: Rawia M. Khalil, Ahmed A. Abd El Rahman, Mahfouz A. Kassem, Mohamed S. El Ridi, Mona M. Abou Samra, Ghada E. A. Awad, Soheir S. Mansy

Abstract:

Solid lipid nanoparticles (SLNs) have gained great attention for the topical treatment of skin associated fungal infection as they facilitate the skin penetration of loaded drugs. Our work deals with the preparation of nystatin loaded solid lipid nanoparticles (NystSLNs) using the hot homogenization and ultrasonication method. The prepared NystSLNs were characterized in terms of entrapment efficiency, particle size, zeta potential, transmission electron microscopy, differential scanning calorimetry, rheological behavior and in vitro drug release. A stability study for 6 months was performed. A microbiological study was conducted in male rats infected with Candida albicans, by counting the colonies and examining the histopathological changes induced on the skin of infected rats. The results showed that SLNs dispersions are spherical in shape with particle size ranging from 83.26±11.33 to 955.04±1.09 nm. The entrapment efficiencies are ranging from 19.73±1.21 to 72.46±0.66% with zeta potential ranging from -18.9 to -38.8 mV and shear-thinning rheological Behavior. The stability studies done for 6 months showed that nystatin (Nyst) is a good candidate for topical SLN formulations. A least number of colony forming unit/ ml (cfu/ml) was recorded for the selected NystSLN compared to the drug solution and the commercial Nystatin® cream present in the market. It can be fulfilled from this work that SLNs provide a good skin targeting effect and may represent promising carrier for topical delivery of Nyst offering the sustained release and maintaining the localized effect, resulting in an effective treatment of cutaneous fungal infection.

Keywords: candida infections, hot homogenization, nystatin, solid lipid nanoparticles, stability, topical delivery

Procedia PDF Downloads 360
1311 Using Computer Simulations to Prepare Teachers

Authors: Roberta Gentry

Abstract:

The presentation will begin with a brief literature review of the use of computer simulation in teacher education programs. This information will be summarized. Additionally, based on the literature review, advantages and disadvantages of using computer simulation in higher education will be shared. Finally, a study in which computer simulations software was used with 50 initial licensure teacher candidates in both an introductory course and a behavior management course will be shared. Candidates reflected on their experiences with using computer simulation. The instructor of the course will also share lessons learned.

Keywords: simulations, teacher education, teacher preparation, educational research

Procedia PDF Downloads 621
1310 Design, Implementation, and Evaluation of ALS-PBL Model in the EMI Classroom

Authors: Yen-Hui Lu

Abstract:

In the past two decades, in order to increase university visibility and internationalization, English as a medium of instruction (EMI) has become one of the main language policies in higher education institutions where English is not a dominant language. However, given the complex, discipline-embedded nature of academic communication, academic literacy does not come with students’ everyday language experience, and it is a challenge for all students. Particularly, to engage students in the effective learning process of discipline concepts in the EMI classrooms, teachers need to provide explicit academic language instruction to assist students in deep understanding of discipline concepts. To bridge the gap between academic language development and discipline learning in the EMI classrooms, the researcher incorporates academic language strategies and key elements of project-based learning (PBL) into an Academic Language Strategy driven PBL (ALS-PBL) model. With clear steps and strategies, the model helps EMI teachers to scaffold students’ academic language development in the EMI classrooms. ALS-PBL model includes three major stages: preparation, implementation, and assessment. First, in the preparation stage, ALS-PBL teachers need to identify learning goals for both content and language learning and to design PBL topics for investigation. Second, during the implementation stage, ALS-PBL teachers use the model as a guideline to create a lesson structure and class routine. There are five important elements in the implementation stage: (1) academic language preparation, (2) connecting background knowledge, (3) comprehensible input, (4) academic language reinforcement, and (5) sustained inquiry and project presentation. Finally, ALS-PBL teachers use formative assessments such as student learning logs, teachers’ feedback, and peer evaluation to collect detailed information that demonstrates students’ academic language development in the learning process. In this study, ALS-PBL model was implemented in an interdisciplinary course entitled “Science is Everywhere”, which was co-taught by five professors from different discipline backgrounds, English education, civil engineering, business administration, international business, and chemical engineering. The purpose of the course was to cultivate students’ interdisciplinary knowledge as well as English competency in disciplinary areas. This study used a case-study design to systematically investigate students’ learning experiences in the class using ALS-PBL model. The participants of the study were 22 college students with different majors. This course was one of the elective EMI courses in this focal university. The students enrolled in this EMI course to fulfill the school language policy, which requires the students to complete two EMI courses before their graduation. For the credibility, this study used multiple methods to collect data, including classroom observation, teachers’ feedback, peer assessment, student learning log, and student focus-group interviews. Research findings show four major successful aspects of implementing ALS-PBL model in the EMI classroom: (1) clear focus on both content and language learning, (2) meaningful practice in authentic communication, (3) reflective learning in academic language strategies, and (4) collaborative support in content knowledge.This study will be of value to teachers involved in delivering English as well as content lessons to language learners by providing a theoretically-sound practical model for application in the classroom.

Keywords: academic language development, content and language integrated learning, english as a medium of instruction, project-based learning

Procedia PDF Downloads 55
1309 Determination of Vitamin C (Ascorbic Acid) in Orange Juices Product

Authors: Wanida Wonsawat

Abstract:

This research describes a voltammetric approach to determine amounts of vitamin C (Ascorbic acid) in orange juice sample, using three screen printed electrode. The anodic currents of vitamin C were proportional to vitamin C concentration in the range of 0 – 10.0 mM with the limit of detection of 1.36 mM. The method was successfully employed with 2 µL of the working solution dropped on the electrode surface. The proposed method was applied for the analysis of vitamin C in packed orange juice without sample purification or complexion of sample preparation step.

Keywords: ascorbic acid, vitamin C, juice, voltammetry

Procedia PDF Downloads 302
1308 Study on Preparation and Storage of Jam Incorporating Carrots (Dacus Carrota), Banana (Musa Acuminata) and Lime (Citrus Aurantifola)

Authors: K. Premakumar, D. S. Rushani, H. N. Hettiarachchi

Abstract:

The production and consumption of preserved foods have gained much importance due to globalization, and they provide a health benefit apart from the basic nutritional functions. Therefore, a study was conducted to develop a jam incorporating carrot, banana, and lime. Considering the findings of several preliminary studies, five formulations of the jam were prepared by blending different percentages of carrot and banana including control (where the only carrot was added). The freshly prepared formulations were subjected to physicochemical and sensory analysis.Physico-Chemical parameters such as pH, TSS, titrable acidity, ascorbic acid content, total sugar and non-reducing sugar and organoleptic qualities such as colour, aroma, taste, spread ability and overall acceptability and microbial analysis (total plate count) were analyzed after formulations. Physico-Chemical Analysis of the freshly prepared Carrot –Banana Blend jam showed increasing trend in titrable acidity (from 0.8 to 0.96, as % of citric acid), TSS (from 70.05 to 67.5 0Brix), ascorbic acid content (from 0.83 to 11.465 mg/100ml), reducing sugar (from 15.64 to 20.553%) with increase in carrot pulp from 50 to 100%. pH, total sugar, and non-reducing sugar were also reduced when carrot concentration is increased. Five points hedonic scale was used to evaluate the organoleptic characters. According to Duncan's Multiple Range Test, the mean scores for all the assessed sensory characters varied significantly (p<0.05) in the freshly made carrot-banana blend jam formulations. Based on the physicochemical and sensory analysis, the most preferred carrot: banana combinations of 50:50, 100:0 and 80:20 (T1, T2, and T5) were selected for storage studies.The formulations were stored at 300 °C room temperature and 70-75% of RH for 12 weeks. The physicochemical characteristics were measured at two weeks interval during storage. The decreasing trends in pH and ascorbic acid and an increasing trend in TSS, titrable acidity, total sugar, reducing sugar and non-reducing sugar were noted with advancement of storage periods of 12 weeks. The results of the chemical analysis showed that there were significance differences (p<0.05) between the tested formulations. Sensory evaluation was done for carrot –banana blends jam after a period of 12 weeks through a panel of 16 semi-trained panelists. The sensory analysis showed that there were significant differences (p<0.05) for organoleptic characters between carrot-banana blend jam formulations. The highest overall acceptability was observed in formulation with 80% carrot and 20% banana pulp. Microbiological Analysis was carried out on the day of preparation, 1 month, 2 months and 3 months after preparation. No bacterial growth was observed in the freshly made carrot -banana blend jam. There were no counts of yeast and moulds and coliforms in all treatments after the heat treatments and during the storage period. Only the bacterial counts (Total Plate Counts) were observed after three months of storage below the critical level, and all formulations were microbiologically safe for consumption. Based on the results of physio-chemical characteristics, sensory attributes, and microbial test, the carrot –banana blend jam with 80% carrot and 20% banana (T2) was selected as best formulation and could be stored up to 12 weeks without any significant changes in the quality characteristics.

Keywords: formulations, physicochemical parameters, microbiological analysis, sensory evaluation

Procedia PDF Downloads 181
1307 Optimization of Batch to Up-Scaling of Soy-Based Prepolymer Polyurethane

Authors: Flora Elvistia Firdaus

Abstract:

The chemical structure of soybean oils have to be chemically modified through its tryglyceride to attain resemblance properties with petrochemicals. Sulfur acid catalyst in peracetic acid co-reagent has good performance on modified soybean oil strucutures through its unsaturated fatty acid moiety to the desired hydroxyl functional groups. A series of screening reactions have indicated that the ratio of acetic/peroxide acid 1:7.25 (mol/mol) with temperature of 600°C for soy-epoxide synthesis are prevailed for up-scaling of bodied soybean into 10 and 20 folds from initials. A two-step process was conducted for the preparation of soy-polyol in designated temperatures.

Keywords: soybean, polyol, up-scaling, polyurethane

Procedia PDF Downloads 328
1306 Development of Composition and Technology of Vincristine Nanoparticles Using High-Molecular Carbohydrates of Plant Origin

Authors: L. Ebralidze, A. Tsertsvadze, D. Berashvili, A. Bakuridze

Abstract:

Current cancer therapy strategies are based on surgery, radiotherapy and chemotherapy. The problems associated with chemotherapy are one of the biggest challenges for clinical medicine. These include: low specificity, broad spectrum of side effects, toxicity and development of cellular resistance. Therefore, anti-cance drugs need to be develop urgently. Particularly, in order to increase efficiency of anti-cancer drugs and reduce their side effects, scientists work on formulation of nano-drugs. The objective of this study was to develop composition and technology of vincristine nanoparticles using high-molecular carbohydrates of plant origin. Plant polysacharides, particularly, soy bean seed polysaccharides, flaxseed polysaccharides, citrus pectin, gum arabic, sodium alginate were used as objects. Based on biopharmaceutical research, vincristine containing nanoparticle formulations were prepared. High-energy emulsification and solvent evaporation methods were used for preparation of nanosystems. Polysorbat 80, polysorbat 60, sodium dodecyl sulfate, glycerol, polyvinyl alcohol were used in formulation as emulsifying agent and stabilizer of the system. The ratio of API and polysacharides, also the type of the stabilizing and emulsifying agents are very effective on the particle size of the final product. The influence of preparation technology, type and concentration of stabilizing agents on the properties of nanoparticles were evaluated. For the next stage of research, nanosystems were characterized. Physiochemical characterization of nanoparticles: their size, shape, distribution was performed using Atomic force microscope and Scanning electron microscope. The present study explored the possibility of production of NPs using plant polysaccharides. Optimal ratio of active pharmaceutical ingredient and plant polysacharids, the best stabilizer and emulsifying agent was determined. The average range of nanoparticles size and shape was visualized by SEM.

Keywords: nanoparticles, target delivery, natural high molecule carbohydrates, surfactants

Procedia PDF Downloads 239
1305 Addressing Factors Associated with Vertical HIV Transmission among Pregnant Women in Rwanda

Authors: Murorunkwere Marie Claire

Abstract:

Introduction: In Sub-Saharan Africa and specifically in Rwandan rural areas, mother-to-Child human immunodeficiency virus transmission remains a big challenge. This is mainly due to lack of awareness and ignorance among pregnant rural women, leading to neglect regular taking of prophylactic antiretroviral treatment and to persistently beliefs in traditional healers and home deliveries. This paper explores the factors associated with stagnant reduction in human immunodeficiency virus vertical transmission among pregnant rural women and provides solutions to tackle it. Methodology: The first phase of this research will be a qualitative survey was conducted to assess the knowledge, attitudes and practices towards vertical human immunodeficiency virus transmission among pregnant women in one rural district in Rwanda. The data generated from phase one of this research will be used to address the main factors revealed through community mobilization and motivation on attending required antenatal consultations and hospital deliveries, proper and regular antiretroviral treatment taking, and discouraging beliefs in traditional healers and home deliveries. Refresher training seminars will also be organized for healthcare providers qualified on conducting deliveries about current measures to maximize the reduction of chances that can lead to mother -child contamination (to avoid early rupture of membranes and to prevent any source of contamination). Results: This paper is expected to contribute in a significant reduction of the vertical human immunodeficiency virus transmission burden among pregnant rural women. Conclusion: Strong campaigns on prevention of mother- to-child human immunodeficiency virus transmission and community mobilization of pregnant rural women, and house to house education and continuous reminders as well as training seminars to health care personnel on updated measures is, key in addressing vertical human immunodeficiency virus transmission.

Keywords: attitudes transformation, community mobilisation, pregnant rural women, vertical HIV transmission

Procedia PDF Downloads 54
1304 Structural and Optical Study of Cu doped ZnS Thin Films Nanocrystalline by Chemical Bath Deposition Method

Authors: Hamid Merzouk, D. T. Talantikite, H. Haddad, Amel Tounsi

Abstract:

ZnS is an important II-VI binary compound with large band-gap energy at room temperature. We present in this work preparation and characterization of ZnS and Cu doped ZnS thin films. The depositions are performed by a simple chemical bath deposition route. Structural properties are carried out by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Optical transmittance is investigated by the UV-visible spectroscopy at room temperature.

Keywords: chemical, bath, method, Cu, doped, ZnS, thin, films

Procedia PDF Downloads 523
1303 Physical, Chemical and Environmental Properties of Natural and Construction/Demolition Recycled Aggregates

Authors: Débora C. Mendes, Matthias Eckert, Cláudia S. Moço, Hélio Martins, Jean-Pierre P. Gonçalves, Miguel Oliveira, José P. Da Silva

Abstract:

Uncontrolled disposal of construction and demolition waste (C & DW) in embankments in the periphery of cities causes both environmental and social problems, namely erosion, deforestation, water contamination and human conflicts. One of the milestones of EU Horizon 2020 Programme is the management of waste as a resource. To achieve this purpose for C & DW, a detailed analysis of the properties of these materials should be done. In this work we report the physical, chemical and environmental properties of C & DW aggregates from 25 different origins. The results are compared with those of common natural aggregates used in construction. Assays were performed according to European Standards. Additional analysis of heavy metals and organic compounds such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), were performed to evaluate their environmental impact. Finally, properties of concrete prepared with C & DW aggregates are also reported. Physical analyses of C & DW aggregates indicated lower quality properties than natural aggregates, particularly for concrete preparation and unbound layers of road pavements. Chemical properties showed that most samples (80%) meet the values required by European regulations for concrete and unbound layers of road pavements. Analyses of heavy metals Cd, Cr, Cu, Pb, Ni, Mo and Zn in the C&DW leachates showed levels below the limits established by the Council Decision of 19 December 2002. Identification and quantification of PCBs and PAHs indicated that few samples shows the presence of these compounds. The measured levels of PCBs and PAHs are also below the limits. Other compounds identified in the C&DW leachates include phthalates and diphenylmethanol. In conclusion, the characterized C&DW aggregates show lower quality properties than natural aggregates but most samples showed to be environmentally safe. A continuous monitoring of the presence of heavy metals and organic compounds should be made to trial safe C&DW aggregates. C&DW aggregates provide a good economic and environmental alternative to natural aggregates.

Keywords: concrete preparation, construction and demolition waste, heavy metals, organic pollutants

Procedia PDF Downloads 321
1302 The Ecosystem of Food Allergy Clinical Trials: A Systematic Review

Authors: Eimar Yadir Quintero Tapias

Abstract:

Background: Science is not generally self-correcting; many clinical studies end with the same conclusion "more research is needed." This study hypothesizes that first, we need a better appraisal of the available (and unavailable) evidence instead of creating more of the same false inquiries. Methods: Systematic review of ClinicalTrials.gov study records using the following Boolean operators: (food OR nut OR milk OR egg OR shellfish OR wheat OR peanuts) AND (allergy OR allergies OR hypersensitivity OR hypersensitivities). Variables included the status of the study (e g., active and completed), availability of results, sponsor type, sample size, among others. To determine the rates of non-publication in journals indexed by PubMed, an advanced search query using the specific Number of Clinical Trials (e.g., NCT000001 OR NCT000002 OR...) was performed. As a prophylactic measure to prevent P-hacking, data analyses only included descriptive statistics and not inferential approaches. Results: A total of 2092 study records matched the search query described above (date: September 13, 2019). Most studies were interventional (n = 1770; 84.6%) and the remainder observational (n = 322; 15.4%). Universities, hospitals, and research centers sponsored over half of these investigations (n = 1208; 57.7%), 308 studies (14.7%) were industry-funded, and 147 received NIH grants; the remaining studies got mixed sponsorship. Regarding completed studies (n = 1156; 55.2%), 248 (21.5%) have results available at the registry site, and 417 (36.1%) matched NCT numbers of journal papers indexed by PubMed. Conclusions: The internal and external validity of human research is critical for the appraisal of medical evidence. It is imperative to analyze the entire dataset of clinical studies, preferably at a patient-level anonymized raw data, before rushing to conclusions with insufficient and inadequate information. Publication bias and non-registration of clinical trials limit the evaluation of the evidence concerning therapeutic interventions for food allergy, such as oral and sublingual immunotherapy, as well as any other medical condition. Over half of the food allergy human research remains unpublished.

Keywords: allergy, clinical trials, immunology, systematic reviews

Procedia PDF Downloads 109