Search results for: concrete compressive strength effect

Authors: Stephen W. Wang

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This research aims to explore the multi-faceted structure of airline passengers’ perception of airline sponsorship, and its impact on airline passengers and even consumers on airline brand preferences and brand equity. The connotation of this research is mainly divided into two parts. The first part of the research focuses on exploring the connotation and sub-dimensions of “air passengers’ perception of airline sponsorship”; the second part of the research focuses on integrating “air passengers’ perception on the multi-factor aspect of the corporate sponsorship, “brand transfer theory” and “brand theory”, explores the influence of airlines’ commitment to corporate sponsorship activities on the brand equity and brand preferences of airline passengers, and on passengers’ subsequent behavioral intentions . In addition, in order to clarify the differences between different types of corporate sponsorship activities and events in terms of "air passengers' perception of airline corporate sponsorship activities", brand transfer, brand preference, brand equity and behavioral intentions, this research also focuses on moderating effects of corporate sponsorship events. With the apply of multi-group structural equation model, it is hoped that the effectiveness of the sponsorship activities of airline companies will be improved. In terms of theoretical and practical implications, the aviation industry can follow the results of this research to understand which corporate sponsorship perceptions have a greater impact on consumers, which has important practical significance. The second part of the research project, from the consumer's point of view, understands whether airline corporate sponsorship activities influence behavioral intentions through brand transfer and brand recognition. Through the analysis of the intermediary effect of brand transfer, brand preference and brand equity, the results of this research can provide a more complete and powerful explanation for “why” airlines’ commitment to corporate sponsorship activities can affect airline passengers’ purchase intentions, which will help fill in the gap of the theoretical and practical research on "airline corporate sponsorship", and has its theoretical significance.

Keywords: airline, sponsorship, brand image transfer, brand preference

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Authors: Yasser Almazrua

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Terrorism is a multidimensional phenomenon that has increased recently. Many countries started combating terrorism through security forces; however, there has been relatively little attention given to rehabilitation programs for people involved in such terrorism acts. In Saudi Arabia, after facing so many terrorist attacks, they started understanding and countering terrorism differently by establishing Mohammad bin Naif Counselling and Care Center in 2006. The center now is considered one of the top experience centers in the world for terrorist rehabilitation and ideology correction. The center offers different programs such as training, educational, social, art and psychological programs. One of the approaches that have been used by psychological experts at the center is Narrative Therapy. It is a therapeutic approach that focuses on the ability of the client to identify their personal life story. The client during therapy works as a storyteller where he or she gets insight, meaning and better understanding of their own lives. Because each client at the center had a story, it can be better fit method for rehabilitation towards healing and personal development. The case describes a 34-years-old man who was involved in some terrorism activities locally by technically and financially supporting a terrorist group related to Al-Qaida. The beneficiary joined Mohammad bin Naif Counseling and Care Center after serving his sentence. Informed of consent has been given to the beneficiary before starting the therapeutic program. Both qualitative and quantitative data on the beneficiary are collected by self-reporting during the initial session, and by using a psychological measurement. The result found that the beneficiary was not insightful about himself, and he had a high level of repression which relatedly moved him to be targeted for recruitment in the terrorist group. With rehabilitation and by using the therapeutic approach, the beneficiary improved on the level of insight, specifically about himself and also about the experience. This case illustrates the importance of considering the effect of Narrative Therapy in terrorist rehabilitation programs.

Keywords: narrative therapy, rehabilitation, Saudi Arabia, terrorism

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Authors: Supanitayanon Lalita, Dechkunakorn Surachai, Anuwongnukroh Niwat, Srikhirin Toemsak, Roongrujimek Pitchaya, Tua-Ngam Peerapong

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Objective: To compare maximum load, percentage of elongation, physical characteristics of 4 types of dental floss: (1) Thai Silk Floss (silk, waxed), (2) Oral B® Essential Floss (nylon, waxed), (3) Experimental Floss Xu (nylon, unwaxed), (4) Experimental Floss Xw (nylon, waxed). Materials & method: Four types of floss were tested (n=30) with a Universal Testing Machine (Instron®). Each sample (30 cm long, 5 cm segment) was fixed, and pulled apart with load cell of 100 N and a test speed of 100 mm/min. Physical characteristics were investigated by digital microscope under 2.5×10 magnification, and scanning electron microscope under 1×100 and 5×100 magnification. The size of the filaments was measured in micron (μm) and the fineness were measured in Denier. Statistical analysis: For mechanical properties, the maximum load and the percentage of elongation were presented as mean ± SD. The distribution of the data was calculated by the Kolmogorov-Smirnov test. One-way ANOVA and multiple comparison (Tukey HSD) were used to analyze the differences among the groups with the level of a statistical difference at p < 0.05. Results: The maximum load of Floss Xu, Floss Xw, Oral B and Thai Silk were 47.39, 46.46, 25.38, and 23.70 N, respectively. The percentage of elongation of Oral B, Floss Xw, Floss Xu and Thai Silk were 72.43, 44.62, 31.25, and 16.44%, respectively. All 4 types of dental floss showed statistically differences in both the maximum load and percentage of elongation at p < 0.05, except for maximum load between Floss Xw and Floss Xu that showed no statistically significant difference. Physical characteristics of Thai silk revealed the most disintegrated, the smallest, and the least fine filaments. Conclusion: Floss Xu had the highest maximum load. Oral B had the highest percentage of elongation. Wax coating on Floss X increased the elongation but had no significant effect on the maximum load. The physical characteristics of Thai Silk resulted in the lowest mechanical properties values.

Keywords: dental floss, maximum load, mechanical property, percentage of elongation, physical property

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Authors: Jureerat Kilsomporn, Chularat Howharn

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The aim of this qualitative study was to describe the meaning of leisure and the role of leisure among elderly people aged more than 80. Participants were purposive selected. Inclusion criteria were age more than 80 year, has no disease, and independent for daily life activities. Data were collected by in-depth interview. Each participant was interviewed two times and 45-60 minutes in each time of interview. Content analyses were conducted to describe the findings. The findings were as followed. Ten active aging participated in this study. All of them are Buddhist with age between 83-89 years old. Most of them completed the primary school. All of them were active members of community club such as elderly club, women club, and funeral association. Active aging described leisure as activities that connected them with their communities. Leisure could be categorized into three groups which were religious activities, entertainment activities, and hobbies. Examples of religious activities were ordination, house-blessing ceremony, and wedding ceremony. Examples of entertainment activities were Thai dance, beat a drum, and sang local songs. Participants described more that they joined and did in leisure for a sake of pleasure. These leisure played significant roles; significantly affect were their minds and their spiritual. Religious activities play a significant role in spiritual well-being while entertainment activities play a significant role in maintaining good status of mental health. Effect of hobby activities which most of these were payable activities were increased their self-valued. Although it was not high incomes but they can use their own money as they designed. Moreover, participants describe that they have a feeling of use their time wisely since they can earn the money, they can have an exercise, and they can share the time with their neighborhood with these activities. Suggestions from this study were that authorized personnel should promote leisure for aging regularly and continuously. Any facilities that meet with their need and their desired should be promoted since these can facilitate aging to maintain their good health status.

Keywords: active aging, activities, elderly, leisure

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Authors: Alireza Taghdiri, Sara Ghanbarzade Ghomi

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Existing buildings are permanently subjected to change, continuously renovated and repaired in their long service life. Old buildings are destroyed and their material and components are recycled or reused for constructing new ones. In this process, importance of sustainability principles for building construction is obviously known and great significance must be attached to consumption of resources, resulting effects on the environment and economic costs. Utilization strategies for extending buildings service life and delay in destroying have positive effect on environment protection. In addition, simpler alterability or expandability of buildings’ structures and reducing energy and natural resources consumption have benefits for users, producers and environment. To solve these problems, by applying theories of open building, structural components of some conventional building systems have been analyzed and then, a new geometry adaptive building system is developed which can transform and support different imposed loads. In order to achieve this goal, various research methods and tools such as professional and scientific literatures review, comparative analysis, case study and computer simulation were applied and data interpretation was implemented using descriptive statistics and logical arguments. Therefore, hypothesis and proposed strategies were evaluated and an adaptable and reusable 2-dimensional building system was presented which can respond appropriately to dwellers and end-users needs and provide reusability of structural components of building system in new construction or function. Investigations showed that this incremental building system can be successfully applied in achieving the architectural design objectives and by small modifications on components and joints, it is easy to obtain different and adaptable load-optimized component alternatives for flexible spaces.

Keywords: adaptability, durability, open building, service life, structural building system

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Authors: Seetanah Boopen, Padachi Kesseven, R. Juwaheer , R. V. Sannassee, M. L. Lamport

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This study aims primarily at investigating the importance of soft infrastructure in tourism development for the case of an island economy namely Mauritius. The study in the first place assesses the level of perceived and actual satisfaction of the present state of the different types of soft tourism infrastructure and the allied services provided by tourism stakeholders in Mauritius and address the identified gaps. In order to address the study objectives, a rigorous survey analysis among 1741 international tourists at the departure lounge of the Sir Seewoosagur International Airport of Mauritius was carried out. The respondents placed significant emphasis on the different elements of the soft infrastructure dimension, where many of the elements falling under this dimension were rated with a high mean score. In particular the visitors rated communication, both internet and telephone services, and security to be most important. Significant gap has been found in the categories of ‘Health’ and ‘Security’. This indicates that the tourists ascribe high importance to the soft infrastructure dimension. The link between the respondent profile and the key variables which influence the tourist choice of the island as a destination are found to be equally important for most of the international tourists. However, these were deemed to be more critical for tourists travelling with family members. Although the survey instrument attempted to measure any gap between on the one hand, the importance of the infrastructure dimension and on the other hand, the level of satisfaction with the infrastructure dimension, overall the results do not show any statistically significant gap among the different elements of the infrastructural dimension. The study dwells into further analysis by engaging into an econometric framework related to a Probit Model, using the data collected, to gauge the effect of soft infrastructure on tourist intention to repeat or recommend the destination. The results confirm that soft infrastructure is found to be sensible to tourists, although relatively less sensitive as compared to tourism and transport and hotel infrastructure.

Keywords: tourism development, soft infrastructure, Mauritius, hotel infrastructure

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Authors: Atif Zafar Khan, Swarnendra Singh, Imrana Naseem

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Breast cancer is one of the most frequent malignancies in women worldwide and a leading cause of cancer-related deaths among women. Therefore, there is a need to identify new chemotherapeutic strategies for cancer treatment. Unlike normal cells, cancer cells contain elevated copper levels which play an integral role in angiogenesis. Copper is an important metal ion associated with the chromatin DNA, particularly with guanine. Thus, targeting copper via copper-specific chelators in cancer cells can serve as effective anticancer strategy. Keeping in view these facts, we evaluated the anticancer activity and copper-dependent cytotoxic effect of coumestrol (phytoestrogen in soybean products) in breast cancer MCF-7 cells. Coumestrol inhibited proliferation and induced apoptosis in MCF-7 cells, which was prevented by copper chelator neocuproine and ROS scavengers. Coumestrol treatment induced ROS generation coupled to DNA fragmentation, up-regulation of p53/p21, cell cycle arrest at G1/S phase, mitochondrial membrane depolarization and caspases 9/3 activation. All these effects were suppressed by ROS scavengers and neocuproine. These results suggest that coumestrol targets elevated copper for redox cycling to generate ROS leading to DNA fragmentation. DNA damage leads to p53 up-regulation which directs the cell cycle arrest at G1/S phase and promotes caspase-dependent apoptosis of MCF-7 cells. In conclusion, coumestrol induces pro-oxidant cell death by chelating cellular copper to produce copper-coumestrol complexes that engages in redox cycling in breast cancer cells. Thus, targeting elevated copper levels might be a potential therapeutic strategy for selective cytotoxic action against malignant cells.

Keywords: apoptosis, breast cancer, copper chelation, coumestrol, reactive oxygens species, redox cycling

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Authors: Ahmet Koyuncu, Abdullah Berkan Erdogmus, Orkun Dogu, Sinan Uygur

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Thermoelectric modules are integrated to electronic components to keep their temperature in specific values in electronic cooling applications. They can be used in different ambient temperatures. The cold side temperatures of thermoelectric modules depend on their hot side temperatures, operation currents, and heat loads. Performance curves of thermoelectric modules are given at most two different hot surface temperatures in product catalogs. Characteristic properties are required to select appropriate thermoelectric modules in thermal design phase of projects. Generally, manufacturers do not provide characteristic material property values of thermoelectric modules to customers for confidentiality. Common commercial software applied like ANSYS ICEPAK, FloEFD, etc., include thermoelectric modules in their libraries. Therefore, they can be easily used to predict the effect of thermoelectric usage in thermal design. Some software requires only the performance values in different temperatures. However, others like ICEPAK require three temperature-dependent equations for material properties (Seebeck coefficient (α), electrical resistivity (β), and thermal conductivity (γ)). Since the number and the variety of thermoelectric modules are limited in this software, definitions of characteristic material properties of thermoelectric modules could be required. In this manuscript, the method of derivation of characteristic material properties from the datasheet of thermoelectric modules is presented. Material characteristics were estimated from two different performance curves by experimentally and numerically in this study. Numerical calculations are accomplished in ICEPAK by using a thermoelectric module exists in the ICEPAK library. A new experimental setup was established to perform experimental study. Because of similar results of numerical and experimental studies, it can be said that proposed equations are approved. This approximation can be suggested for the analysis includes different type or brand of TEC modules.

Keywords: electrical resistivity, material characteristics, thermal conductivity, thermoelectric coolers, seebeck coefficient

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Authors: Muhammad Sohail Sajid, Mahvish Maqbool, Hafiz Muhammad Rizwan, Muhammad Saqib, Haroon Ahmad

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Ticks are blood-sucking ectoparasite that causes a decrease in production and economic losses and affects mammals, reptiles, and birds. Hyalomma anatolicum is the main vector for CCHF transmission and Pakistan has faced several outbreaks of CCHF in the recent past. Ferritin (fer)is a highly conserved molecule that is ubiquitous in most tick tissues and responsible for iron metabolism and storage. It was hypothesized that the development of acaricidal resistance and residual effects of commercially used acaricides could be controlled by using alternative control methods, including RNA interference. The current study aimed to evaluate the fer silencing effects on tick feeding, average body weight, egg mass index, and mortality. Ticks, collected through the standard collection protocols were further subjected to RNA isolation using the Trizol method. Commercially available kit procedures were followed for cDNA and dsRNA synthesis. The soaking/Immersion method was used for dsRNA delivery. Our findings have shown a 27% reduction in body weight of fer silenced group and showed a significant association of fer and body weight. Silencing of fer had a significant effect on the engorgement percentage (P= 0.0007), oviposition (P=0.008), egg mass (P= 0.004) and hatching (P= 0.001). The soaking method was used for dsRNA delivery and 15°C was found to be an optimum temperature for inducing gene silencing in ticks as at this temperature, maximum survivability after immersion was attained. This study along with previous studies, described that iron toxicity due to the silencing of fer could play an important role in the control of ticks and fer can be used as a potent candidate for vaccine development.

Keywords: ticks, iron, ferritin, engorgement, oviposition, immersion, RNA interference

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Authors: Ya'u Muhammad, Umar Umar A. Mallammadori, Dahiru Mansur

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Effect of kaempferol on haematological parameters in two weeks old broiler chickens with experimental Eimeria tenella infection was evaluated in this study. Sixty-day old broilers were randomly allotted into six groups (I-VI) of ten broilers each and brooded for two weeks with commercial broiler feed (vital feed®) and provided water ad libitum. At two weeks of age broilers in group 1 were neither infected nor treated. Broilers in groups II-VI were infected with Eimeria tenella sporulated oocyst (104/ml) via oral inoculation. After infection was established, broilers in groups II-IV were treated orally with 1 mg/kg, 1.5 mg/kg, and 2 mg/kg of kaempferol, respectively. Broilers in group V were treated for five days with amprolium, 1.25 g/L in drinking water. Broilers in group VI were administered normal saline, 5 ml/kg per os for five days. Five days post infection; all broilers were sacrificed by severing their jugular veins. Blood sample from each bird was collected in EDTA container for haematology. Caecal contents were harvested and used to determine the lesion score and caecal Oocyst count respectively. Data obtained was analyzed using pad prism version 5.0. Mean Packed Cell Volume (PCV), haemoglobin (Hb) concentration, and Red Blood Cell (RBC) count significantly (P < 0.05) increased in groups II, III, and IV in a dose dependent manner. Similarly, PCV, Hb concentration, and RBC count significantly (P < 0.05) increased in groups II, III, and IV when compared to VI. No significant (P > 0.05) difference in the mean values of PCV, Hb and RBC count were recorded between groups treated with kaempferol and group V. Caecal Oocyst counts and lesion scores reduced significantly (P < 0.05) in groups II, III, and IV in a dose dependent manner. It was therefore observed in this study that kaempferol improved haematological parameters and reduced Oocyst count as well as the lesion scores in broilers infected with Eimeria tenella.

Keywords: broilers, Eimeria tenella, kaempferol, lesion scores, oocyst count,

Procedia PDF Downloads 194

Authors: Folajinmi Oluwasina, Greg Abiaziem, Moses Luke, Mobolaji Kolawole, Nancy Yibowei, Anne Taiwo

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Background: Occurrence of HIV infection has an adverse effect on the natural causes of Hepatitis B Viral (HBV) infection, faster progression of hepatic fibrosis demonstrated in patients with co-infection. This study was carried out to determine the incidence of HBV infection among HIV-positive patients, and to retrospectively evaluate laboratory characteristics of patients with HIV/HBV co-infection. Methods: A retrospective analysis of patient files for all HIV-infected cases followed-up and treated at 52 health facilities. Among HIV-infected cases, those with HBsAg positivity and HIV/Hepatitis B co-infection were determined. Socio demographic, alcohol or substance use, ART, CD4, Viral Load levels and treatment durations were retrospectively evaluated. Results: Of the 125 HIV-infected patients evaluated retrospectively, 17 (13.6%) had HBsAg positivity. Of these 17 cases were 11(64.7%) male and 6 (35.3%) female, with a mean age of 48.7 years. No patients had a history of alcohol or substance use. The mean duration of follow up was 28 months. 9 (52.9%) patients had negative HBV DNA at presentation while 8(47%) had positive HBV DNA, with normal ALT levels in all subjects. Among the 9 cases with negative HBV DNA who had no indication for the treatment of chronic hepatitis B. In five cases, treatment was commenced since HBV DNA was elevated in conjunction with low CD4. One patient in whom treatment was not indicated based on HBV DNA and CD4 levels in conjunction with the absence of AIDS defining clinical picture was currently being followed-up without treatment. Of the patients receiving HAART therapy, the average CD4 count at presentation was 278 cells/mm3 vs. 466 cells/mm3 at the end of 12 months. In three subjects with positive HBV DNA, a decrease in HBV DNA was noted after initiation of treatment. In four patients with negative DNA who received treatment, the HBV DNA negative status was found to remain, while one patient who did not receive treatment had elevated HBV DNA and decreased CD4 levels. Conclusion: It was shown that this group of patients with HIV/HBV co-infection, HAART was found to be associated with a decrease in HBV DNA in HBV DNA positive cases, absence of transition to positivity among those with negative HBV DNA, and with increased CD4 in all subjects.

Keywords: Hepatitis B, DNA, anti retroviral therapy, co-infection

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Authors: Ivan Zupan, Tomislav Saric, Suzana Tkalcic

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IMUNO-2865® is a commercially available, β–glucan based, natural hemicellulose compound with proven immunostimulative properties in people, domestic and some aquatic animals. During the experimental feeding trial with IMUNO-2865® in juvenile wild-caught chub under laboratory conditions, supplementation resulted in overall higher growth performance for all experimental groups regardless of the concentration of the added compound. The maximum, 5% concentration of the supplement, resulted in highest weight gain and calculated specific growth rate. In sea bream, as economically most important species in the Mediterranean aquaculture, significant increases in numbers of monocytes and heterophils were observed in the group supplemented with 2.5 % of IMUNO-2865® in the feed. An overall increase of erythrocytes was noted by the end of the experiment, although with variable distribution among groups. Blood Ca++ levels, total proteins, and total NH₃ were significantly higher after 60 days of feeding in all treatment groups compared to the control and remained elevated in the treated group following the secession of supplementation. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and serum paraoxonase PON1 (U/L) showed similar trends. All these parameters are playing a significant role in either oxygen supplementation of tissues, or anabolic and catabolic processes that on molecular levels contribute to the overall health and immune-building capacity of cells and tissues. The complete lack of mortality in sea bream and presented increases in cellular, biochemical and oxidative stress parameters in the blood suggest that the IMUNO-2865® represents a safe dietary supplement for in aquaculture, with an overall positive and potentially immunostimulative effect on farmed fish.

Keywords: IMUNO-2865®, β–glucans, Mediterranean aquaculture, fish imunnostimulans

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Authors: Wang Jie

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This article advances the reform of Chinese migration law through an analysis of the updated and former versions of the Chinese migration law, specifically for the Exit-Entry Administration Law of the People’s Republic of China and Regulations on Foreigners’ Permanent Residence in the People’s Republic of China(Exposure Draft), which was most recently issued in 2012 and 2020 respectively. After a fundamental reform of China’s migration law, China’s immigration legal framework has become relatively well developed compared with the previous one. Immigration procedures are available online and these procedures have become relatively simple. Comparative research for the Chinese migration laws has been done during the past several years for its legislation, legal reference for western countries and its preliminary implementation. Some results show that the reform is a superficial one and may not have a practical effect on China’s current immigration legal framework. However, complete results cannot be obtained only through the comparative research of legal definitions. Some practical case studies will also be required to analyze in detail to demonstrate the reasons that some reforms still remain at the superficial level and what further progress is required in China's immigration legal framework. This is a perspective that has been overlooked in most comparative law studies. In the first part, this article will conduct a simple comparative study of the reform of Chinese migration law and use cases studies to illustrate the reform of Chinese migration law. In the second part, this article will point out another perspective that is easily overlooked, that is, how do the Chinese nationals treat the reform: whether it is a legislative advance or a failure, and whether it deepens social tensions between nationals and immigrants. In the third part, the article will discuss Chinese migration law through China’s international law perspective with international organizations, such as International Organization for Migration and International Labour Organization will also be discussed to dialectically judge the reform of Chinese migration law. This article will adopt case and comparative studies to conduct overall research based on the reform of Chinese migration law and try to put forward more constructive advice for China’s immigration legal framework.

Keywords: Chinese migration law, reform, foreigners, immigration legal framework

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Authors: Saeed Poormoaied

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Perishability and developing an intelligent control policy for perishable items are the major concerns of marketing managers in a supply chain. In this study, we address a two-echelon supply chain problem for perishable items with a single vendor and a single buyer. The buyer adopts an aged-based continuous review policy which works by taking both the stock level and the aging process of items into account. The vendor works under the warehouse framework, where its lot size is determined with respect to the batch size of the buyer. The model holds for a positive and fixed lead time for the buyer, and zero lead time for the vendor. The demand follows a Poisson process and any unmet demand is lost. We provide exact analytic expressions for the operational characteristics of the system by using the renewal reward theorem. Items have a fixed lifetime after which they become unusable and are disposed of from the buyer's system. The age of items starts when they are unpacked and ready for the consumption at the buyer. When items are held by the vendor, there is no aging process which results in no perishing at the vendor's site. The model is developed under the centralized framework, which takes the expected profit of both vendor and buyer into consideration. The goal is to determine the optimal policy parameters under the service level constraint at the retailer's site. A sensitivity analysis is performed to investigate the effect of the key input parameters on the expected profit and order quantity in the supply chain. The efficiency of the proposed age-based policy is also evaluated through a numerical study. Our results show that when the unit perishing cost is negligible, a significant cost saving is achieved.

Keywords: two-echelon supply chain, perishable items, age-based policy, renewal reward theorem

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Authors: Saâd Oukkass, Abderrahim Bouftou, Rachid Ouchn, L. Lebrun, Miloudi Hlaibi

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We invariably exist in a world steeped in colors, whether in our clothing, food, cosmetics, or even medications. However, most of the dyes we use pose significant problems, being both harmful to the environment and resistant to degradation. Among these dyes, methylene blue and acid yellow 61 stand out, commonly used to dye various materials such as cotton, wood, and silk. Fortunately, various methods have been developed to treat and remove these polluting dyes, among which membrane processes play a prominent role. These methods are praised for their low energy consumption, ease of operation, and their ability to achieve effective separation of components. Adsorption on activated carbon is also a widely employed technique, complementing the basic processes. It proves particularly effective in capturing and removing organic compounds from water due to its substantial specific surface area while retaining its properties unchanged. In the context of our study, we examined two crucial aspects. Firstly, we explored the possibility of selectively extracting methylene blue from a mixture containing another dye, acid yellow 61, using a polymer inclusion membrane (PIM) made of PVA. After characterizing the morphology and porosity of the membrane, we applied kinetic and thermodynamic models to determine the values of permeability (P), initial flux (J0), association constant (Kass), and apparent diffusion coefficient (D*). Subsequently, we measured activation parameters (activation energy (Ea), enthalpy (ΔH#ass), entropy (ΔS#)). Finally, we studied the effect of activated carbon on the processes carried out through the membrane, demonstrating a clear improvement. These results make the membrane developed in this study a potentially pivotal player in the field of membrane separation.

Keywords: dyes, methylene blue, membrane, activated carbon

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Authors: Chaebong Kim, Yongmin Cho, Minkyung Han, Mooyoung Kim, KooSang Kim

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Background: Air pollution from global warming has a considerable influence on respiratory disease and atopic dermatitis (AD). Present studies base on a hypothesis about correlation between air pollutant and AD, and the results are analyzed from various points of view. Objectives: This study aimed to integrate the relevant researches for air pollutant and AD, and to perform the systematic literature review and meta-analysis to provide the basis of air pollutant control. Methods: Research materials were collected from original articles published in English academic journals including medicine, nursing and health science from August 1 to 31, 2016. We collected the materials from Pubmed, Medline, Embase, Cochrane Central database with Prisma (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) based on the Cochrane Systematic Review Manual, and performed the evaluation and analysis for selected materials. We got the research results for risk of bias using Rev-Man ver. 5.2, and meta analyses using STATA. Results: The prevalence of infantile atopic dermatitis were 1.05 times higher than other groups who were exposed to air pollution, and exposure to NO2 (1.08, 95% CI: 1.02 – 1.14), O3 (1.09, 95% CI: 1.04 – 1.15), SO2 (1.07, 95% CI: 1.02 – 1.12) in subgroup air pollutant was considerably associated with infantile atopic dermatitis. The prevalence of infantile atopic dermatitis was 1.03 times higher than other groups who were exposed to PM2.5, but the results were not statistically similar. Conclusion: Health effect from environmental pollution risen people’s interest in environmental diseases. Air pollutant was associated with AD in this study, but selected literature was based on non-RCT (Randomized Controlled Trial) study. Therefore, there was a limit in study method including control, matching, and correction of confounding variables. For clear conclusion, it is necessary to develop the appropriate tool for object of study and clear standard to measure of air pollutant.

Keywords: air pollution, atopic dermatitis, children, meta-analysis

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Authors: Reza Fardid, Aliyeh Alipour

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Introduction: Coronary heart disease (CHD) is the most common and deadliest diseases. A coronary angiography is an important tool for the diagnosis and treatment of this disease. Because angiography is performed by exposure to ionizing radiation, it can lead to harmful effects. Ionizing radiation induces double-stranded breaks in DNA, which is a potentially life-threatening injury. The purpose of the present study is an investigation of the phosphorylation of histone H2AX in the location of the double-stranded break in Peripheral blood lymphocytes as an indication of Biological effects of radiation on angiography patients. Materials and Methods: This method is based on measurement of the phosphorylation of histone (gamma-H2AX, gH2AX) level on serine 139 after formation of DNA double-strand break. 5 cc of blood from 24 patients with angiography were sampled before and after irradiation. Blood lymphocytes were removed, fixed and were stained with specific ϒH2AX antibodies. Finally, ϒH2AX signal as an indicator of the double-strand break was measured with Flow Cytometry Technique. Results and discussion: In all patients, an increase was observed in the number of breaks in double-stranded DNA after irradiation (20.15 ± 14.18) compared to before exposure (1.52 ± 0.34). Also, the mean of DNA double-strand break was showed a linear correlation with DAP. However, although induction of DNA double-strand breaks associated with radiation dose in patients, the effect of individual factors such as radiosensitivity and regenerative capacity should not be ignored. If in future we can measure DNA damage response in every patient angiography and it will be used as a biomarker patient dose, will look very impressive on the public health level. Conclusion: Using flow cytometry readings which are done automatically, it is possible to detect ϒH2AX in the number of blood cells. Therefore, the use of this technique could play a significant role in monitoring patients.

Keywords: coronary angiography, DSB of DNA, ϒH2AX, ionizing radiation

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Authors: F. A. Gberindyer, M. O.Abatan, A. B. Saba

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Background: Gentamicin is an aminoglycoside antibiotic used in the treatment of infections caused by Gram-negative aerobic bacteria organisms in human and animals. In Nigeria, there are arrays of multisource generic versions of injectable gentamicin sulphate in the drug markets. There is a high prevalence of counterfeit and substandard drugs in the third world countries with consequent effect on their therapeutic efficacy and safety. Aim: The aim of this study was to investigate pharmaceutical equivalence of some of these generics used in veterinary practice in Nigeria. Methodology: About 20 generics of injectable gentamicin sulphate were sampled randomly across Nigeria but 15 were analyzed for identity and potency. Identity test was done using Fourier transform infra red spectroscopy and the spectral for each product compared with that of the USP reference standard for similarity. Microbiological assay using agar diffusion method with E. coli as a test organism on nutrient agar was employed and the respective diameters of bacterial inhibition zones obtained after 24 hour incubation at 37°C. The percent potency for each product was thereafter calculated and compared with the official specification. Result And Discussion: None of the generics is produced in any African country. About 75 % of the products are imported from China whereas 60 % of the veterinary generics are manufactured in Holland. Absorption spectra for the reference and test samples were similar. Percent potencies of all test products were within the official specification of 95-115 %. Nigeria relies solely on imported injectable gentamicin sulphate products. All sampled generic versions passed both identity and potency tests. Clinicians should ensure that drugs are used rationally since the converse could be contributing to the therapeutic failures reported for most of these generics. Bioequivalence study is recommended to ascertain their interchangeability when parenteral extra venous routes are indicated.

Keywords: generics, gentamicin, identity, multisource, potency

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Authors: J. O. Idoko, C. N. Michael, T. O. Fasuan

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This study investigated the effects of cooking time, seed-to-water ratio and soaking time on proximate and functional properties of African walnut seed using Box-Behnken design and Response Surface Methodology (BBD-RSM) with a view to increase its utilization in the food industry. African walnut seeds were sorted washed, soaked, cooked, dehulled, sliced, dried and milled. Proximate analysis and functional properties of the samples were evaluated using standard procedures. Data obtained were analyzed using descriptive and inferential statistics. Quadratic models were obtained to predict the proximate and functional qualities as a function of cooking time, seed-to-water ratio and soaking time. The results showed that the crude protein ranged between 11.80% and 23.50%, moisture content ranged between 1.00% and 4.66%, ash content ranged between 3.35% and 5.25%, crude fibre ranged from 0.10% to 7.25% and carbohydrate ranged from 1.22% to 29.35%. The functional properties showed that soluble protein ranged from 16.26% to 42.96%, viscosity ranged from 23.43 mPas to 57 mPas, emulsifying capacity ranged from 17.14% to 39.43% and water absorption capacity ranged from 232% to 297%. An increase in the volume of water used during cooking resulted in loss of water soluble protein through leaching, the length of soaking time and the moisture content of the dried product are inversely related, ash content is inversely related to the cooking time and amount of water used, extraction of fat is enhanced by increase in soaking time while increase in cooking and soaking times result into decrease in fibre content. The results obtained indicated that African walnut could be used in several food formulations as protein supplement and binder.

Keywords: African walnut, functional properties, proximate analysis, response surface methodology

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Authors: Fikiru Temesgen Gelata

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Food security, adaptation, and climate change mitigation are all problems that can be resolved simultaneously with Climate-Smart Agriculture (CSA). This study examines determinants of climate-smart agriculture (CSA) practices among smallholder farmers, aiming to understand the factors guiding adoption decisions and evaluate the impact of CSA on smallholder farmer income in the study areas. For this study, three-stage sampling techniques were applied to select 230 smallholders randomly. Mann-Kendal test and multinomial endogenous switching regression model were used to analyze trends of decrease or increase within long-term temporal data and the impact of CSA on the smallholder farmer income, respectively. Findings revealed education level, household size, land ownership, off-farm income, climate information, and contact with extension agents found to be highly adopted CSA practices. On the contrary, erosion exerted a detrimental impact on all the agricultural practices examined within the study region. Various factors such as farming methods, the size of farms, proximity to irrigated farmlands, availability of extension services, distance to market hubs, and access to weather forecasts were recognized as key determinants influencing the adoption of CSA practices. The multinomial endogenous switching regression model (MESR) revealed that joint adoption of crop rotation and soil and water conservation practices significantly increased farm income by 1,107,245 ETB. The study recommends that counties and governments should prioritize addressing climate change in their development agendas to increase the adoption of climate-smart farming techniques.

Keywords: climate-smart practices, food security, Oincome, MERM, Ethiopia

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Authors: M. G. Ghanem, A. M. M. A. Allam, Diaa E. Fawzy, Mehmet Faruk Cengiz

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This paper is devoted to the design and implementation of a smartwatch textile antenna for Wi-Fi bio-medical applications in millimetric wave bands. The antenna is implemented on a leather textile-based substrate to be embedded in a smartwatch. It enables the watch to pick Wi-Fi signals without the need to be connected to a mobile through Bluetooth. It operates at 60 GHz or WiGig (Wireless Gigabit Alliance) band with a wide band for higher rate applications. It also could be implemented over many stratified layers of the body organisms to be used in the diagnosis of many diseases like diabetes and cancer. The structure is designed and simulated using CST (Studio Suite) program. The wearable patch antenna has an octagon shape, and it is implemented on leather material that acts as a flexible substrate with a size of 5.632 x 6.4 x 2 mm3, a relative permittivity of 2.95, and a loss tangent of 0.006. The feeding is carried out using differential feed (discrete port in CST). The work provides five antenna implementations; antenna without ground, a ground is added at the back of the antenna in order to increase the antenna gain, the substrate dimensions are increased to 15 x 30 mm2 to resemble the real hand watch size, layers of skin and fat are added under the ground of the antenna to study the effect of human body tissues human on the antenna performance. Finally, the whole structure is bent. It is found that the antenna can achieve a simulated peak realized gain in dB of 5.68, 7.28, 6.15, 3.03, and 4.37 for antenna without ground, antenna with the ground, antenna with larger substrate dimensions, antenna with skin and fat, and bent structure, respectively. The antenna with ground exhibits high gain; while adding the human organisms absorption, the gain is degraded because of human absorption. The bent structure contributes to higher gain.

Keywords: bio medical engineering, millimetric wave, smart watch, textile antennas, Wi-Fi

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Authors: Firsan Nova

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The average Indonesian watches 5.5 hours of TV a day. With a population of 242 million people and a Free-to-Air (FTA) TV penetration rate of 56%, that equates to 745 million hours of television watched each day. With such potential, it is no wonder that many companies are now attempting to get into the Pay TV market. Research firm Media Partner Asia has forecast in its study that the number of Indonesian pay-television subscribers will climb from 2.4 million in 2012 to 8.7 million by 2020, with penetration scaling up from 7 percent to 21 percent. Key drivers of market growth, the study says, include macro trends built around higher disposable income and a rising middle class, with leading players continuing to invest significantly in sales, distribution and content. New entrants, in the meantime, will boost overall prospects. This study aims to examine and analyze the effect of Market Attractiveness and the Core Competence on Value Creation and Competitive Advantage and its impact to Business Performance in the pay TV industry in Indonesia. The study using strategic management science approach with the census method in which all members of the population are as sample. Verification method is used to examine the relationship between variables. The unit of analysis in this research is all Indonesian Pay TV business units totaling 19 business units. The unit of observation is the director and managers of each business unit. Hypothesis testing is performed by using statistical Partial Least Square (PLS). The conclusion of the study shows that the market attractiveness affects business performance through value creation and competitive advantage. The appropriate value creation comes from the company ability to optimize its core competence and exploit market attractiveness. Value creation affects competitive advantage. The competitive advantage can be determined based on the company's ability to create value for customers and the competitive advantage has an impact on business performance.

Keywords: market attractiveness, core competence, value creation, competitive advantage, business performance

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Authors: Jan Gayl Barcelon, N. Gorgonio

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Renal tubular acidosis, a medical condition that involves the accumulation of acid in the body due to failure of the kidneys to maintain normal urine and blood pH, is rarely encountered in pregnancy. The effect of renal tubular acidosis in pregnancy is not fully established. It may worsen during pregnancy and cause maternal and fetal morbidity. A 30-year-old primigravida was diagnosed with renal tubular acidosis at age 7, but due to uncontrolled disease progression, she developed rickets at age 10. She was first seen in our institution at eight weeks gestation and maintained on bicarbonate and potassium supplementation. At 26 weeks gestation, she was diagnosed with polyhydramnios, causing on and off irregular uterine contractions. At 30 weeks gestation, despite oral Nifedipine, premature labor was uncontrolled; hence she was admitted for tocolysis. With elevated creatinine (123 umol/L) and a normal blood urea nitrogen level (6.70 mmol/L), she was referred to Nephrology Service, which cleared the patient prior to MgSO₄ drip. Dosing of 4g MgSO₄ over 20 minutes followed by a maintenance of 2g/hour x 24 hours for neuroprotection and tocolysis was ordered. Two hours after MgSO₄ drip initiation, hematuria developed with adequate urine output. The infusion was immediately stopped. The serum magnesium level was high normal at 6.7 mEq/L. After 4 hours of renal clearance, the repeat serum magnesium level was normal (2.7 mEq/L) and with clear urine output. The patient was then given Nifedipine 30mg/tab, 3x a day which controlled the uterine contractions. At 37 weeks gestation, the patient delivered via primary low transverse Cesarean Section to a live female with a birthweight of 2470gm, appropriate for gestational age. The use of MgSO₄ for the control of premature labor in patients with chronic renal disease secondary to renal tubular can cause hematuria.

Keywords: hematuria, magnesium sulfate, premature labor, renal tubular acidosis

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Authors: Israel Oguche

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Journalism practice has faced several challenges across the globe, particularly in developing countries such as Nigeria. While Nigeria has thrived under democratic experiment for twenty years since the return to democracy in 1999, there is still a great lacuna in freedom of expression, such that the presidents, though elected democratically, have had the tendencies to use military might in clamping down on journalism practices across the country. Under Muhammadu Buhari, it seems Nigeria has returned to the military era when powers were used against who says what, on a media, so today, in Nigeria, there are obvious cases of outright human rights violations and detention of journalists whose offenses were not spelled out. From Abiri Jones to Abba Jalingo and Omoyele Sowore, Nigeria journalists have been placed under the cocoon of the tyrannical administration of Muhammadu Buhari, the president, with subsequent clamping down on the instruments of freedoms such as access to justice and fair hearing. This paper gave vivid analytical and empirical perspectives of journalism practice under the dark days of Muhammadu Buhari as Nigeria’s president. The objectives include; examining the core cases of attacks on journalists since 2015 to date, determining the burden of practicing journalism in a tyrannical government, reeling out the effects of restrictive practices of journalism on freedom of expression among Nigerians and proffering solutions for improvement in the years ahead. Using the cognitive dissonance theory, the survey method was used for the study, with qualitative research analysis as a tool for data presentation. In the findings, the number of journalists in jail for publishing objectively under the Buhari administration remains high while the government has clamped down on freedom of expression among the people. The study concluded that there is a need for repelling of laws made by the Nigeria government in order to save the Nigerian journalism industry from total collapse.

Keywords: communication, developing democracy, press freedom, journalism practices

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Authors: Ramy Bakir

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Advancements in the field of nanoscience and nanotechnology have had a sweeping effect on the manufacturing industry in the last two decades, and have specifically allowed for the enhancement of a multitude of applications in the field of building technology. Research carried out in the architectural field in the past decade highlights how those enhancements have improved the structural and environmental performance of buildings, and/or how they developed the aesthetic value of façade or interior treatments. In developing countries, such as Egypt, the actual use of those nano-enhanced applications and their benefits rarely manifest. Hence this paper investigates the socio-technical relationship between the architectural design process and nanotechnology in Cairo using participant observation within an ethnographic study. The study focused on the socio-cultural context of an environmental design process in a specific design firm, and the role of nano-enhanced applications in it, and provided a thick description of the design decisions made within the preliminary stages of the design process of a residential building in Cairo, Egypt. Using Grounded Theory, and through the analysis and coding of the qualitative data collected, this paper was able to identify specific socio-cultural issues influencing individual architect cognition, clarifying how the context of the design process of the studied project affected the design team members’ responses to nano-enhanced materials. This paper presents those findings within a framework of the three identified statuses of response to nanotechnology and classifies the socio-cultural reasons influencing them. In doing so, the paper aims to shed more light on the relation between nanotechnology and architects in their natural environment, and hence allow both to benefit more from a clearer understanding of how the socio-cultural context, along with the benefits of using nanotechnology, influences the design decisions made.

Keywords: nanotechnology, design process, socio-cultural context, nano-enhanced applications

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Authors: Lovorka Galetic, Zeljko Vukelic

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The advanced concepts of strategic and innovation management in the sphere of company dynamic and innovation capabilities, and achieving their mutual alignment and a synergy effect, are important elements in business today. This paper analyses the theory and empirically investigates the influence of a company’s dynamic capabilities on its innovation capabilities. A new multidimensional model of dynamic capabilities is presented, consisting of five factors appropriate to real time requirements, while innovation capabilities are considered pursuant to the official OECD and Eurostat standards. After examination of dynamic and innovation capabilities indicated their theoretical links, the empirical study testing the model and examining the influence of a company’s dynamic capabilities on its innovation capabilities showed significant results. In the study, a research model was posed to relate company dynamic and innovation capabilities. One side of the model features the variables that are the determinants of dynamic capabilities defined through their factors, while the other side features the determinants of innovation capabilities pursuant to the official standards. With regard to the research model, five hypotheses were set. The study was performed in late 2014 on a representative sample of large and very large Croatian enterprises with a minimum of 250 employees. The research instrument was a questionnaire administered to company top management. For both variables, the position of the company was tested in comparison to industry competitors, on a fivepoint scale. In order to test the hypotheses, correlation tests were performed to determine whether there is a correlation between each individual factor of company dynamic capabilities with the existence of its innovation capabilities, in line with the research model. The results indicate a strong correlation between a company’s possession of dynamic capabilities in terms of their factors, due to the new multi-dimensional model presented in this paper, with its possession of innovation capabilities. Based on the results, all five hypotheses were accepted. Ultimately, it was concluded that there is a strong association between the dynamic and innovation capabilities of a company. 

Keywords: dynamic capabilities, innovation capabilities, competitive advantage, business results

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Authors: Smart E. Amanfo

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Although the exact functional relationship between energy consumption and economic growth and development remains a complex social science, there is a sustained growing of agreement among energy economists and the likes on direct or indirect role of energy use in the development process, and as sustenance for many of societal achieved socio-economic and environmental developments in any economy. According to OECD, the world economy will double by 2050 in which the two members of BRICS (Brazil, Russia, India, China and South Africa) countries: China and India lead. There is a global apprehension that if countries constituting the epicenter of the present and future economic growth follow the same trajectory as during and after Industrial Revolution, involving higher energy throughputs, especially fossil fuels, the already known and models predicted threats of climate change and global warming could be exacerbated, especially in the developing economies. The international community’s challenge is how to address the trilemma of economic growth, social development, poverty eradication and stability of the ecological systems. This paper aims at providing the estimates of economic growth, energy consumption, and carbon dioxide emissions using BRICS members’ panel data from 1980 to 2017. The preliminary results based on fixed effect econometric model show positive significant relationship between energy consumption and economic growth. The paper further identified a strong relationship between economic growth and CO2 emissions which suggests that the global agenda of low-carbon-led growth and development is not a straight forward achievable The study therefore highlights the need for BRICS member states to intensify low-emissions-based production and consumption policies, increase renewables in order to avoid further deterioration of climate change impacts.

Keywords: BRICS, sustainability, sustainable development, energy consumption, economic growth

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Authors: Kotchamon Yodkhum, Thawatchai Phaechamud

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Hydrophobic chitosan-based materials have been developed as controlled drug delivery system. This study was aimed to prepare and evaluate chitosan-aluminum monostearate composite dispersion (CLA) as fabricating liquid for construct a hydrophobic, controlled-release solid drug delivery matrix. This work was attempted to blend hydrophobic substance, aluminum monostearate (AMS), with chitosan in acidic aqueous medium without using any surfactants or grafting reaction, and high temperature during mixing that are normally performed when preparing hydrophobic chitosan system. Lactic acid solution (2%w/v) was employed as chitosan solvent. CLA dispersion was prepared by dispersing different amounts of AMS (1-20% w/w) in chitosan solution (4% w/w) with continuous agitation using magnetic stirrer for 24 h. Effect of AMS amount on physicochemical properties of the dispersion such as viscosity, rheology and particle size was evaluated. Morphology of chitosan-AMS complex (dispersant) was observed under inverted microscope and atomic force microscope. Stability of CLA dispersions was evaluated after preparation within 48 h. CLA dispersions containing AMS less than 5 % w/w exhibited rheological behavior as Newtonian while that containing higher AMS amount exhibited as pseudoplastic. Particle size of the dispersant was significantly smaller when AMS amount was increased up to 5% w/w and was not different between the higher AMS amount system. Morphology of the dispersant under inverted microscope displayed irregular shape and their size exhibited the same trend with particle size measurement. Observation of the dispersion stability revealed that phase separation occurred faster in the system containing higher AMS amount which indicated lower stability of the system. However, the dispersions were homogeneous and stable more than 12 hours after preparation that enough for fabrication process. The prepared dispersions had ability to be fabricated as a porous matrix via lyophilization technique.

Keywords: chitosan, aluminum monostearate, dispersion, controlled-release

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Authors: A. D. Zikiryahodjaev, L. V. Bolotina, A. S. Sukhotko

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Purpose. To evaluate the expediency and timeliness of performance of surgical treatment as a component of multi-therapy treatment of patients with stage IV breast cancers. Materials and Methods. This investigation comparatively analyzed the results of complex treatment with or without surgery in patients with metastatic breast cancer. We analyzed retrospectively treatment experience of 196 patients with generalized breast cancer in the department of oncology and breast reconstructive surgery of P.A. Herzen Moscow Cancer Research Institute from 2000 to 2012. The average age was (58±1,1) years. Invasive ductul carcinoma was verified in128 patients (65,3%), invasive lobular carcinoma-33 (16,8%), complex form - 19 (9,7%). Complex palliative care involving drug and radiation therapies was performed in two patient groups. The first group includes 124 patients who underwent surgical intervention as complex treatment, the second group includes 72 patients with only medical therapy. Standard systemic therapy was given to all patients. Results. Overall, 3-and 5-year survival in fist group was 43,8 and 21%, in second - 15,1 and 9,3% respectively [p=0,00002 log-rank]. Median survival in patients with surgical treatment composed 32 months, in patients with only systemic therapy-21. The factors having influencing an influence on the prognosis and the quality of life outcomes for of patients with generalized breast cancer were are also studied: hormone-dependent tumor, Her2/neu hyper-expression, reproductive function status (age, menopause existence). Conclusion.Removing primary breast tumor in patients with generalized breast cancer improve long-term outcomes. Three- and five-year survival increased by 28,7 and 16,3% respectively, and median survival–for 11 months. These patients may benefit from resection of the breast tumor. One explanation for the effect of this resection is that reducing the tumor load influences metastatic growth.

Keywords: breast cancer, combination therapy, factors of prognosis, primary tumor

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Authors: Priya Varshney, Soumya S. Mohapatra

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Fabrication of anti-corrosion and self-cleaning superhydrophobic coatings for metallic surfaces which are regenerable and durable in the aggressive conditions has shown tremendous interest in materials science. In this work, the superhydrophobic coatings on metallic surfaces (aluminum, steel, copper) were prepared by two-step and one-step chemical etching process. In two-step process, roughness on surface was created by chemical etching and then passivation of roughened surface with low surface energy materials whereas, in one-step process, roughness on surface by chemical etching and passivation of surface with low surface energy materials were done in a single step. Beside this, the effect of etchant concentration and etching time on wettability and morphology was also studied. Thermal, mechanical, ultra-violet stability of these coatings were also tested. Along with this, regeneration of coatings and self-cleaning, corrosion resistance and water repelling characteristics were also studied. The surface morphology shows the presence of a rough microstuctures on the treated surfaces and the contact angle measurements confirms the superhydrophobic nature. It is experimentally observed that the surface roughness and contact angle increases with increase in etching time as well as with concentration of etchant. Superhydrophobic surfaces show the excellent self-cleaning behaviour. Coatings are found to be stable and maintain their superhydrophobicity in acidic and alkaline solutions. Water jet impact, floatation on water surface, and low temperature condensation tests prove the water-repellent nature of the coatings. These coatings are found to be thermal, mechanical and ultra-violet stable. These durable superhydrophobic metallic surfaces have potential industrial applications.

Keywords: superhydrophobic, water-repellent, anti-corrosion, self-cleaning

Procedia PDF Downloads 279