Search results for: in vitro growth
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7578

Search results for: in vitro growth

5868 Impact of Trade Cooperation of BRICS Countries on Economic Growth

Authors: Svetlana Gusarova

Abstract:

The essential role in the recent development of world economy has led to the developing countries, notably to BRICS countries (Brazil, Russia, India, China, South Africa). Over the next 50 years the BRICS countries are expected to be the engines of global trade and economic growth. Trade cooperation of BRICS countries can enhance their economic development. BRICS countries were among Top 10 world exporters of office and telecom equipment, of textiles, of clothing, of iron and steel, of chemicals, of agricultural products, of automotive products, of fuel and mining products. China was one of the main trading partners of all BRICS countries, maintaining close relationship with all BRICS countries in the development of trade. Author analyzed trade complementarity of BRICS countries and revealed the high level of complementarity of their trade flows in connection with availability of specialization in different types of goods. The correlation and regression analysis of communication of Intra-BRICS merchandise turnover and their GDP (PPP) revealed very strong impact on the development of their economies.

Keywords: BRICS countries, trade cooperation, complementarity, regression analysis

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5867 The Development of Chinese Film Market as Factor of Change in Global Hollywood

Authors: Marcin Adamczak

Abstract:

The growth of Chinese film market and its dynamic incomparable to any other historical phenomenon has already made China the second world market and potential future leader in 2-3 years period. The growing power of Chines box-office and its future prospects is then the crucial and potentially disturbing factor for persistence of global Hollywood reality. The paper is based on market statistical data. The main findings of the analysis are defining of essential obstacles for the development of Chinese market and its foreign expansion. However, the new strategies employed by the industry (acquisitions of cinema chains abroad, blockbuster made with the involvement of figures from Hollywood star system, coproduction ties within Pacific basin) could be a successful remedy for current shortcomings. The main factor for development will be wider economical framework and maintenance of growth pace. The future state of Chinese film market will be one of the main factors shaping global film culture and film market in following decades of XXI century.

Keywords: production studies, film market, Chinese film market, distribution

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5866 The Relationship between Urbanization and the Rapid Development of Real Estate Industry in China: Taking Chongqing as an Example

Authors: Deng Tingting

Abstract:

There is a very close interaction between the rapid development of the real estate industry and regional urbanization. The real estate problem can be boiled down to the problem of urbanization, in essence. The growth of hundreds of millions of people in the future will determine the development of low-level demand in the real estate market. At the same time, the practical problems of urbanization also seriously restrict the healthy development of real estate itself. The latter two interact with each other by adjusting the industrial structure, economic aggregate, regional population flow, and many other linkage factors. Through the case analysis of Chongqing, this paper finds that the urbanization of Chongqing and the overall development level of the real estate industry are still in the stage of development and upgrading, and its development potential and future development and application space are still very large. Therefore, from the perspective of the regional economy, studying the interaction between the two is of great significance to accelerate the process of urbanization in Chongqing, promote the healthy development of the real estate industry, and promote the rapid growth of the regional economy.

Keywords: urbanization, demographics, real estate, interrelationships

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5865 Growth Performance and Meat Quality of Cobb 500 Broilers Fed Phytase and Tannase Treated Sorghum-Based Diets

Authors: Magaya Rutendo P., Mutibvu Tonderai, Nyahangare emmanuel T., Ncube Sharai

Abstract:

This study aimed to evaluate the effects of phytase and tannase addition in broiler diets on growth performance and meat quality of broilers fed sorghum-based diets. Twelve experimental diets were formulated at three sorghum levels, which include 0, 50, and 100%, and 4 enzyme levels: No enzyme, 5000FTU phytase, 25TU tannase, and a combination of 5000FTU phytase plus 25TU tannase. Data on voluntary feed intake, average weekly weight gain and feed conversion ratio were recorded and used to assess growth performance. Meat technical and nutritional parameters were used to determine meat quality. Broilers fed total sorghum diets with phytase and tannase enzyme combination had the highest feed intake in the first (24.4 ± 0.04g/bird/day) and second weeks of life (23.0 ± 1.06g/bird/day), respectively. Complete sorghum diets with phytase (83.0 ± 0.88g/bird/day) and tannase (122.0 ± 0.88g/bird/day) showed the highest feed intake in the third and fourth weeks, respectively. Broilers fed 50% sorghum diets with tannase (135.3 ± 0.05g/bird/day) and complete maize diets with phytase (158.1 ± 0.88g/bird/day) had the highest feed intake during weeks five and six, respectively. Broilers fed a 50% sorghum diet without enzymes had the highest weight gain in the final week (606.5 ± 32.39g). Comparable feed conversion was observed in birds fed complete maize and 50% sorghum diets. Dietary treatment significantly influences the live body, carcass, liver, kidneys, abdominal fat pad weight, and intestinal length. However, it did not affect Pectoralis major meat nutritional and technical parameters.

Keywords: feed efficiency, sorghum, carcass, exogenous enzymes

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5864 Effects of Adding Condensed Tannin from Shrub and Tree Leaves in Concentrate on Sheep Production Fed on Elephant Grass as a Basal Diet

Authors: Kusmartono, Siti Chuzaemi, Hartutik dan Mashudi

Abstract:

Two studies were conducted involving an in vitro (Expt 1) and in vivo (Expt 2) measurements. Expt 1. aimed to evaluate effects of adding CT extracts on gas production and efficiency of microbial protein synthesis (EMPS), Expt 2 aimed to evaluate effects of supplementing shrub/tree leaves as CT source on feed consumption, digestibility, N retention, body weight gain and dressing percentage of growing sheep fed on elephant grass (EG) as a basal diet.Ten shrub and tree leaves used as CT sources were wild sunflower (Tithonia diversifolia), mulberry (Morus macroura), cassava (Manihot utilissima), avicienna (Avicennia marina), calliandra (Calliandra calothyrsus), sesbania (Sesbania grandiflora), acacia (acacia vilosa), glyricidia (Glyricidia sepium), jackfruit (Artocarpus heterophyllus), moringa (Moringa oleifera). The treatments applied in Expt 1 were: T1=Elephant grass (60%)+concentrate (40%); T2 = T1 + CT (3% DM); T3= T2 + PEG; T4 = T1 + CT (3.5% DM); T5 = T4 + PEG; T6 = T1 + CT (4% DM) and T7 = T6 + PEG. Data obtained were analysed using Randomized Block Design. Statistical analyses showed that treatments significanty affected (P<0.05) total gas production and EMPS. The lowest values of total gas production (45.9 ml/500 mg DM) and highest value of EMPS (64.6 g/kg BOTR) were observed in the treatment T4 (3.5% CT from cassava leave extract). Based on this result it was concluded that this treatment was the best and was chosen for further investigation using in vivo method. The treatmets applied for in vivo trial were: T1 = EG (60%) + concentrate (40%); T2 = T1 + dried cassava leave (equivalent to 3.5% CT); T3 = T2 + PEG. 18 growing sheep aging of 8-9 months and weighing of 23.67kg ± 1.23 were used in Expt 2. Results of in vivo study showed that treatments significanty affected (P<0.05) nutrients intake and digestibility (DM, OM and CP). N retention for sheep receiving treatment T2 were significantly higher (P<0.05; 15.6 g/d) than T1 (9.1 g/d) and T3 (8.53 g/d). Similar results were obtained for daily weight gain where T2 were the highest (62.79 g/d), followed by T1 (51.9 g/d) and T3 (52.85 g/d). Dressing percentage of T2 was the highest (51.54%) followed by T1 (49.61%) and T3 (49.32%). It can be concluded that adding adding dried cassava leaves did not reduce palatability due to CT, but rather increased OM digestibility and hence feed consumption was improved. N retention was increased due to the action of CT in the cassava leaves and this may have explained a higher input of N into duodenum which was further led to higer daily weight gain and dressing percentage.

Keywords: in vitro gas production, sheep, shrub and tree leaves, condensed tannin

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5863 Window Analysis and Malmquist Index for Assessing Efficiency and Productivity Growth in a Pharmaceutical Industry

Authors: Abbas Al-Refaie, Ruba Najdawi, Nour Bata, Mohammad D. AL-Tahat

Abstract:

The pharmaceutical industry is an important component of health care systems throughout the world. Measurement of a production unit-performance is crucial in determining whether it has achieved its objectives or not. This paper applies data envelopment (DEA) window analysis to assess the efficiencies of two packaging lines; Allfill (new) and DP6, in the Penicillin plant in a Jordanian Medical Company in 2010. The CCR and BCC models are used to estimate the technical efficiency, pure technical efficiency, and scale efficiency. Further, the Malmquist productivity index is computed to measure then employed to assess productivity growth relative to a reference technology. Two primary issues are addressed in computation of Malmquist indices of productivity growth. The first issue is the measurement of productivity change over the period, while the second is to decompose changes in productivity into what are generally referred to as a ‘catching-up’ effect (efficiency change) and a ‘frontier shift’ effect (technological change). Results showed that DP6 line outperforms the Allfill in technical and pure technical efficiency. However, the Allfill line outperforms DP6 line in scale efficiency. The obtained efficiency values can guide production managers in taking effective decisions related to operation, management, and plant size. Moreover, both machines exhibit a clear fluctuations in technological change, which is the main reason for the positive total factor productivity change. That is, installing a new Allfill production line can be of great benefit to increasing productivity. In conclusions, the DEA window analysis combined with the Malmquist index are supportive measures in assessing efficiency and productivity in pharmaceutical industry.

Keywords: window analysis, malmquist index, efficiency, productivity

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5862 Effects of Bile Acids and Lipase Supplementation in Low-Energy Diets on Growth Performance and Meat Quality in Broiler Chickens

Authors: Muhammad Adeel Arshad, Shaukat Ali Bhatti

Abstract:

The study aimed to investigate the effect of bile acids and lipase supplementation in low-energy diets on growth performance and meat quality of broilers. Seven hundred day-old Cobb-500 broiler chicks with an average initial body weight of 45.9 ± 0.3 g were assigned to 5 dietary treatments, with five replications of 28 birds each in a completely randomized design. The five treatments were as follows: (i) HE: broilers received a diet with high energy content; (ii) LE: broilers received a diet with low energy content and energy content reduced by 100 kcal/kg as compared to HE; (iii) LEB: broilers received a diet similar to the LE group supplemented with 300 g/ton bile acids; (iv) LEL: broilers received a diet similar to the LE group supplemented with 180 g/ton lipase enzyme and (v) LEBL: broilers received a diet similar to the LE group supplemented with both 300 g/ton bile acids and 180 g/ton lipase enzyme. The experimental period lasted for 35 days. Broilers fed HE had a lower (P < 0.05) body weight (BW) gain and lower feed intake (1-35 d), but during finisher period (21-35 d), BW gain was similar with other treatments. Feed conversion ratio (FCR) was lower in HE and higher in LEBL group (P < 0.05), while the LE, LEB, and LEL had intermediate values. At 35 d no difference occurred between treatment for water holding capacity and pH of breast and thigh muscles (P > 0.05). The relative weight of pancreas was higher (P < 0.05) in LEB treatment but lower (P < 0.05) in LEL treatment. In conclusion, bile acids and lipase supplementation at 300 g/ton and 150g/ton of feed in low-energy diets respectively had no effect on broiler performance and meat quality. However, FCR was improved in HE treatment.

Keywords: bile acids, energy, enzyme, growth

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5861 Oxalate Content of Raw and Cooked Amaranth and Strawberry Spinach Grown in an Elevated CO₂ Atmosphere

Authors: Madhuri Kanala, Geoffrey Savage

Abstract:

Worldwide CO₂ levels are slowly rising, and this may have effects on the growth and nutritional composition of many food plants. The production of secondary metabolites such as oxalates has not been investigated in depth. The oxalate content of many food plants are known to have adverse nutritional effects on humans and reduction in the oxalate contents of food plants is a very positive move. Recent studies had shown that the oxalate content of the leaves of spinach and silver beet reduced when the plants were grown in an environment where CO₂ was increased. The response of amaranth and strawberry spinach leaves to changes in the high CO₂ environment have not been understood though it is known that the plants do contain appreciable oxalate contents. A study was conducted where amaranth and strawberry spinach plants were grown in identical plant growth chambers with the same environmental conditions except that one chamber was supplied with ambient air (CO₂ 405 ppm) while the other chamber had the CO₂ level increased to 650 ppm. The total and soluble oxalate content of the leaves of raw and cooked amaranth and strawberry spinach were determined by HPLC and calcium levels were determined using ICP following 6 weeks of growth. The total oxalate content of the fresh leaves of amaranth and strawberry spinach were reduced by 29.5 % and 24.6% respectively in the leaves of the plants grown in increased CO₂ conditions compared to ambient levels. The soluble oxalate content of amaranth leaves grown under ambient and increased CO₂ conditions were future reduced by 42% and 26.8% respectively following cooking as the soluble oxalate was leached into the cooking water and discarded. The reduction of the oxalate and calcium levels of raw and cooked amaranth and strawberry spinach leaves following an increase in CO₂ content in the air is an interesting positive response to an otherwise significant environmental problem.

Keywords: amaranth, calcium oxalate, enriched CO₂, oxalates, strawberry spinach

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5860 Suture Biomaterials Development from Natural Fibers: Muga Silk (Antheraea assama) and Ramie (Boehmeria nivea)

Authors: Raghuram Kandimalla, Sanjeeb Kalita, Bhaswati Choudhury, Jibon Kotoky

Abstract:

The quest for developing an ideal suture material prompted our interest to develop a novel suture with advantageous characteristics to market available ones. We developed novel suture biomaterial from muga silk (Antheraea assama) and ramie (Boehmeria nivea) plant fiber. Field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), attenuated total reflection fourier transform infrared spectroscopy (ATR-FTIR) and thermo gravimetric analysis (TGA) results revealed the physicochemical properties of the fibers which supports the suitability of fibers for suture fabrication. Tensile properties of the prepared sutures were comparable with market available sutures and it found to be biocompatible towards human erythrocytes and nontoxic to mammalian cells. The prepared sutures completely healed the superficial deep wound incisions within seven days in adult male wister rats leaving no rash and scar. Histopathology studies supports the wound healing ability of sutures, as rapid synthesis of collagen, connective tissue and other skin adnexal structures were observed within seven days of surgery. Further muga suture surface modified by exposing the suture to oxygen plasma which resulted in formation of nanotopography on suture surface. Broad spectrum antibiotic amoxicillin was functionalized on the suture surface to prepare an advanced antimicrobial muga suture. Surface hydrophilicity induced by oxygen plasma results in an increase in drug-impregnation efficiency of modified muga suture by 16.7%. In vitro drug release profiles showed continuous and prolonged release of amoxicillin from suture up to 336 hours. The advanced muga suture proves to be effective against growth inhibition of Staphylococcus aureus and Escherichia coli, whereas normal muga suture offers no antibacterial activity against both types of bacteria. In vivo histopathology studies and colony-forming unit count data revealed accelerated wound healing activity of advanced suture over normal one through rapid synthesis and proliferation of collagen, hair follicle and connective tissues.

Keywords: sutures, biomaterials, silk, Ramie

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5859 Relations between Human Capital Investments and Business Excellence in Croatian Companies

Authors: Ivana Tadić, Željana Aljinović Barać, Nikolina Plazonić

Abstract:

Living today in turbulent business environment forces companies to distinguish from each other, securing sustainable competitive growth and competitive advantage. The best possible solution is to invest (effort and financial resources) within companies’ different practices of human resource management (HRM), more specifically in employees’ knowledge, skills and abilities. Applying this approach companies will create enviable level of human capital securing its economic growth. Employees become human capital for their employers at the moment when they contribute with their own knowledge and abilities in creating material and non-material value of the company. The main aim of this research is to explore the relations between human capital investments and business excellence of Croatian companies. Furthermore, the differences in the level of human capital investments with regard to several companies’ characteristics (e.g. size of the company, ownership and type of the industry) are investigated.

Keywords: business excellence, Croatian industries, human capital investments, human resource management

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5858 Green Synthesized Iron Oxide Nanoparticles: A Nano-Nutrient for the Growth and Enhancement of Flax (Linum usitatissimum L.) Plant

Authors: G. Karunakaran, M. Jagathambal, N. Van Minh, E. Kolesnikov, A. Gusev, O. V. Zakharova, E. V. Scripnikova, E. D. Vishnyakova, D. Kuznetsov

Abstract:

Iron oxide nanoparticles (Fe2O3NPs) are widely used in different applications due to its ecofriendly nature and biocompatibility. Hence, in this investigation, biosynthesized Fe2O3NPs influence on flax (Linum usitatissimum L.) plant was examined. The biosynthesized nanoparticles were found to be cubic phase which is confirmed by XRD analysis. FTIR analysis confirmed the presence of functional groups corresponding to the iron oxide nanoparticle. The elemental analysis also confirmed that the obtained nanoparticle is iron oxide nanoparticle. The scanning electron microscopy and the transmission electron microscopy confirm that the average particle size was around 56 nm. The effect of Fe2O3NPs on seed germination followed by biochemical analysis was carried out using standard methods. The results obtained after four days and 11 days of seed vigor studies showed that the seedling length (cm), average number of seedling with leaves, increase in root length (cm) was found to be enhanced on treatment with iron oxide nanoparticles when compared to control. A positive correlation was noticed with the dose of the nanoparticle and plant growth, which may be due to changes in metabolic activity. Hence, to evaluate the change in metabolic activity, peroxidase and catalase activities were estimated. It was clear from the observation that higher concentration of iron oxide nanoparticles (Fe2O3NPs 1000 mg/L) has enhanced peroxidase and catalase activities and in turn plant growth. Thus, this study clearly showed that biosynthesized iron oxide nanoparticles will be an effective nano-nutrient for agriculture applications.

Keywords: catalase, fertilizer, iron oxide nanoparticles, Linum usitatissimum L., nano-nutrient, peroxidase

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5857 Evaluation of Sustainable Blue Economy Development Performance: Method and Case

Authors: Mingbao Chen

Abstract:

After Rio+20, the blue economy rises all over the world, and it has become the focus field of national development. At present, the blue economy has become a new growth point in the field of global economy and the direction of the development of ‘green’ in the ocean. However, in fact, the key factors affecting the development of the blue economy have not been explored in depth, and the development policies and performance of the blue economy have not been scientifically evaluated. This cannot provide useful guidance for the development of the blue economy. Therefore, it is urgent to establish a quantitative evaluation framework to measure the performance of the blue economic development. Based on the full understanding of the connotation and elements of the blue economy, and studying the literature, this article has built an universality and operability evaluation index system, including ecological environment, social justice, sustainable growth, policy measures, and so on. And this article also established a sound evaluation framework of blue economic development performance. At the same time, this article takes China as a sample to test the framework of the adaptability, and to assess the performance of China's blue economic.

Keywords: Blue economy, development performance, evaluation framework, assess method

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5856 Effect of Rice Cultivars and Water Regimes Application as Mitigation Strategy for Greenhouse Gases in Paddy Fields

Authors: Mthiyane Pretty, Mitsui Toshiake, Aycan Murat, Nagano Hirohiko

Abstract:

Methane (CH₄) is one of the most dangerous greenhouse gases (GHG) emitted into the atmosphere by terrestrial ecosystems, with a global warming potential (GWP) 25-34 times that of CO2 on a centennial scale. Paddy rice cultivations are a major source of methane emission and is the major driving force for climate change. Thus, it is necessary to find out GHG emissions mitigation strategies from rice cultivation. A study was conducted at Niigata University. And the prime objective of this research was to determine the effects of rice varieties CH4 lowland (NU1, YNU, Nipponbare, Koshihikari) and upland (Norin 1, Norin 24, Hitachihatamochi) japonica rice varieties using different growth media which was paddy field soil and artificial soil. The treatments were laid out in a split plot design. The soil moisture was kept at 40-50% and 70%, respectively. The CH₄ emission rates were determined by collecting air samples using the closed chamber technique and measuring CH₄ concentrations using a gas chromatograph. CH₄ emission rates varied with the growth, growth media type and development of the rice varieties. The soil moisture was monitored at a soil depth of 5–10 cm with an HydraGO portable soil sensor system every three days for each pot, and temperatures were be recorded by a sensitive thermometer. The lowest cumulative CH4 emission rate was observed in Norin 24, particularly under 40 to 50% soil moisture. Across the rice genotypes, 40-50% significantly reduced the cumulative CH4 , followed by irrigation of 70% soil moisture. During the tillering stage, no significant variation in tillering and plant height was observed between and 70% soil moisture. This study suggests that the cultivation of Norin 24 and Norin 1 under 70% soil irrigation could be effective at reducing the CH4 in rice fields.

Keywords: methane, paddy fields, rice varieties, soil moisture

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5855 Research of Intrinsic Emittance of Thermal Cathode with Emission Nonuniformity

Authors: Yufei Peng, Zhen Qin, Jianbe Li, Jidong Long

Abstract:

The thermal cathode is widely used in accelerators, FELs and kinds of vacuum electronics. However, emission nonuniformity exists due to surface profile, material distribution, temperature variation, crystal orientation, etc., which will cause intrinsic emittance growth, brightness decline, envelope size augment, device performance deterioration or even failure. To understand how emittance is manipulated by emission nonuniformity, an intrinsic emittance model consisting of contributions from macro and micro surface nonuniformity is developed analytically based on general thermal emission model at temperature limited regime according to a real 3mm cathode. The model shows relative emittance increased about 50% due to temperature variation, and less than 5% from several kinds of micro surface nonuniformity which is much smaller than other research. Otherwise, we also calculated emittance growth combining with Monte Carlo method and PIC simulation, experiments of emission uniformity and emittance measurement are going to be carried out separately.

Keywords: thermal cathode, electron emission fluctuation, intrinsic emittance, surface nonuniformity, cathode lifetime

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5854 The Efficacy of Thymbra spicata Ethanolic Extract and its Main Component Carvacrol on In vitro Model of Metabolically-Associated Dysfunctions

Authors: Farah Diab, Mohamad Khalil, Francesca Storace, Francesca Baldini, Piero Portincasaa, Giulio Lupidi, Laura Vergani

Abstract:

Thymbra spicata is a thyme-like plant belonging to the Lamiaceae family that shows a global distribution, especially in the eastern Mediterranean region. Leaves of T. spicata contain large amounts of phenols such as phenolic acids (rosmarinic acid), phenolic monoterpenes (carvacrol), and flavonoids. In Lebanon, T. spicata is currently used as a culinary herb in salad and infusion, as well as for traditional medicinal purposes. Carvacrol (5-isopropyl-2-methyl phenol), the most abundant polyphenol in the organic extract and essential oils, has a great array of pharmacological properties. In fact, carvacrol is largely employed as a food additive and neutraceutical agent. Our aim is to investigate the beneficial effects of T. spicata ethanolic extract (TE) and its main component, carvacrol, using in vitro models of hepatic steatosis and endothelial dysfunction. As a further point, we focused on investigating if and how the binding of carvacrol to albumin, the physiological transporter for drugs in the blood, might be altered by the presence of high levels of fatty acids (FAs), thus impairing the carvacrol bio-distribution in vivo. For that reason, hepatic FaO cells treated with exogenous FAs such as oleate and palmitate mimic hepatosteatosis; endothelial HECV cells exposed to hydrogen peroxide are a model of endothelial dysfunction. In these models, we measured lipid accumulation, free radical production, lipoperoxidation, and nitric oxide release before and after treatment with carvacrol. The carvacrol binding to albumin with/without high levels of long-chain FAs was assessed by absorption and emission spectroscopies. Our findings show that both TE and carvacrol (i) counteracted lipid accumulation in hepatocytes by decreasing the intracellular and extracellular lipid contents in steatotic FaO cells; (ii) decreased oxidative stress in endothelial cells by significantly reducing lipoperoxidation and free radical production, as well as, attenuating the nitric oxide release; (ii) high levels of circulating FAs reduced the binding of carvacrol to albumin. The beneficial effects of TE and carvacrol on both hepatic and endothelial cells point to a nutraceutical potential. However, high levels of circulating FAs, such as those occurring in metabolic disorders, might hinder the carvacrol transport, bio-distribution, and pharmacodynamics.

Keywords: carvacrol, endothelial dysfunction, fatty acids, non-alcoholic fatty liver diseases, serum albumin

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5853 Small Micro and Medium Enterprises Perception-Based Framework to Access Financial Support

Authors: Melvin Mothoa

Abstract:

Small Micro and Medium Enterprises are very significant for the development of their market economies. They are the main creators of the new working places, and they present a vital core of the market economy in countries across the globe. Access to finance is identified as crucial for small, micro, and medium-sized enterprises for their growth and innovation. This paper is conceived to propose a perception-based SMME framework to aid in access to financial support. Furthermore, the study will address issues that impede SMMEs in South Africa from obtaining finance from financial institutions. The framework will be tested against data collected from 200 Small Micro & Medium Enterprises in the Gauteng province of South Africa. The study adopts a quantitative method, and the delivery of self-administered questionnaires to SMMEs will be the primary data collection tool. Structural equation modeling will be used to further analyse the data collected.

Keywords: finance, small business, growth, development

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5852 Investigating the Influence of Solidification Rate on the Microstructural, Mechanical and Physical Properties of Directionally Solidified Al-Mg Based Multicomponent Eutectic Alloys Containing High Mg Alloys

Authors: Fatih Kılıç, Burak Birol, Necmettin Maraşlı

Abstract:

The directional solidification process is generally used for homogeneous compound production, single crystal growth, and refining (zone refining), etc. processes. The most important two parameters that control eutectic structures are temperature gradient and grain growth rate which are called as solidification parameters The solidification behavior and microstructure characteristics is an interesting topic due to their effects on the properties and performance of the alloys containing eutectic compositions. The solidification behavior of multicomponent and multiphase systems is an important parameter for determining various properties of these materials. The researches have been conducted mostly on the solidification of pure materials or alloys containing two phases. However, there are very few studies on the literature about multiphase reactions and microstructure formation of multicomponent alloys during solidification. Because of this situation, it is important to study the microstructure formation and the thermodynamical, thermophysical and microstructural properties of these alloys. The production process is difficult due to easy oxidation of magnesium and therefore, there is not a comprehensive study concerning alloys containing high Mg (> 30 wt.% Mg). With the increasing amount of Mg inside Al alloys, the specific weight decreases, and the strength shows a slight increase, while due to formation of β-Al8Mg5 phase, ductility lowers. For this reason, production, examination and development of high Mg containing alloys will initiate the production of new advanced engineering materials. The original value of this research can be described as obtaining high Mg containing (> 30% Mg) Al based multicomponent alloys by melting under vacuum; controlled directional solidification with various growth rates at a constant temperature gradient; and establishing relationship between solidification rate and microstructural, mechanical, electrical and thermal properties. Therefore, within the scope of this research, some > 30% Mg containing ternary or quaternary Al alloy compositions were determined, and it was planned to investigate the effects of directional solidification rate on the mechanical, electrical and thermal properties of these alloys. Within the scope of the research, the influence of the growth rate on microstructure parameters, microhardness, tensile strength, electrical conductivity and thermal conductivity of directionally solidified high Mg containing Al-32,2Mg-0,37Si; Al-30Mg-12Zn; Al-32Mg-1,7Ni; Al-32,2Mg-0,37Fe; Al-32Mg-1,7Ni-0,4Si; Al-33,3Mg-0,35Si-0,11Fe (wt.%) alloys with wide range of growth rate (50-2500 µm/s) and fixed temperature gradient, will be investigated. The work can be planned as; (a) directional solidification of Al-Mg based Al-Mg-Si, Al-Mg-Zn, Al-Mg-Ni, Al-Mg-Fe, Al-Mg-Ni-Si, Al-Mg-Si-Fe within wide range of growth rates (50-2500 µm/s) at a constant temperature gradient by Bridgman type solidification system, (b) analysis of microstructure parameters of directionally solidified alloys by using an optical light microscopy and Scanning Electron Microscopy (SEM), (c) measurement of microhardness and tensile strength of directionally solidified alloys, (d) measurement of electrical conductivity by four point probe technique at room temperature (e) measurement of thermal conductivity by linear heat flow method at room temperature.

Keywords: directional solidification, electrical conductivity, high Mg containing multicomponent Al alloys, microhardness, microstructure, tensile strength, thermal conductivity

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5851 Spray-Dried, Biodegradable, Drug-Loaded Microspheres for Use in the Treatment of Lung Diseases

Authors: Mazen AlGharsan

Abstract:

Objective: The Carbopol Microsphere of Linezolid, a drug used to treat lung disease (pulmonary disease), was prepared using Buchi B-90 nano spray-drier. Methods: Production yield, drug content, external morphology, particle size, and in vitro release pattern were performed. Results: The work was 79.35%, and the drug content was 66.84%. The surface of the particles was shriveled in shape, with particle size distribution with a mean diameter of 9.6 µm; the drug was released in a biphasic manner with an initial release of 25.2 ± 5.7% at 60 minutes. It later prolonged the release by 95.5 ± 2.5% up to 12 hours. Differential scanning calorimetry (DSC) revealed no change in the melting point of the formulation. Fourier-transform infrared (FT-IR) studies showed no polymer-drug interaction in the prepared nanoparticles.

Keywords: nanotechnology, drug delivery, Linezolid, lung disease

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5850 Impact of Heavy Metal Toxicity on Metabolic Changes in the Diazotrophic Cyanobacterium Anabaena PCC 7120

Authors: Rishi Saxena

Abstract:

Cyanobacteria is a photosynthetic prokaryote, and these obtain their energy through photosynthesis. In this paper, we studied the effect of iron on metabolic changes in the diazotrophic cyanobacterium Anabaena PCC 7120. Nowadays, metal contamination due to natural and anthropogenic sources is a global environment concern. Iron induced changes in growth, N2-fixation, CO2 fixation and photosynthetic activity were studied in a diazotrophic cyanobacterium Anabaena PCC 7120. Iron at 50 uM concentration supported the maximum growth, heterocyst frequency, CO2 fixation, photosystem I (PS I), photosystem II (PS II) and nitrogenase activities in the organism. Higher concentration of iron inhibited these processes. Chl a and PS II activities were more sensitive to iron than the protein and PS I activity. Here, it is also mentioned that heavy metal induced altered macromolecules metabolism and changes in the central dogma of life (DNA→ mRNA → Protein). And also recent advances have been made in understanding heavy metal-cyanobacteria interaction and their application for metal detoxification.

Keywords: cyanobacterium anabaena 7120, nitrogen fixation, photosystem I (PS I), photosystem II (PS II)

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5849 Generation of Charged Nanoparticles and Their Contribution to the Thin Film and Nanowire Growth during Chemical Vapour Deposition

Authors: Seung-Min Yang, Seong-Han Park, Sang-Hoon Lee, Seung-Wan Yoo, Chan-Soo Kim, Nong-Moon Hwang

Abstract:

The theory of charged nanoparticles suggested that in many Chemical Vapour Depositions (CVD) processes, Charged Nanoparticles (CNPs) are generated in the gas-phase and become a building block of thin films and nanowires. Recently, the nanoparticle-based crystallization has become a big issue since the growth of nanorods or crystals by the building block of nanoparticles was directly observed by transmission electron microscopy observations in the liquid cell. In an effort to confirm charged gas-phase nuclei, that might be generated under conventional processing conditions of thin films and nanowires during CVD, we performed an in-situ measurement using differential mobility analyser and particle beam mass spectrometer. The size distribution and number density of CNPs were affected by process parameters such as precursor flow rate and working temperature. It was shown that many films and nanostructures, which have been believed to grow by individual atoms or molecules, actually grow by the building blocks of such charged nuclei. The electrostatic interaction between CNPs and the growing surface induces the self-assembly into films and nanowires. In addition, the charge-enhanced atomic diffusion makes CNPs liquid-like quasi solid. As a result, CNPs tend to land epitaxial on the growing surface, which results in the growth of single crystalline nanowires with a smooth surface.

Keywords: chemical vapour deposition, charged nanoparticle, electrostatic force, nanostructure evolution, differential mobility analyser, particle beam mass spectrometer

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5848 Utilizing Mahogany (Swietenia Macrophylla) Fruits, Leaves, and Branches as Biochar for Soil Amendment in Okra (Abelmoschus Esculentus) Plant

Authors: Ayaka A. Matsuo, Gweyneth Victoria I. Maranan, Shawn Mikel Hobayan

Abstract:

In this study, we delve into the application of mahogany fruits as biochar for soil amendment, aiming to evaluate their effectiveness in improving soil quality and influencing the growth parameters of okra plants through a comprehensive analysis employing various multivariate tests. In a more straightforward approach, our results show that biochar derived from isn't just a minor player but emerges as a key contributor to our study. This finding holds profound implications, as it highlights the material significance of biochar derived from Mahogany (Swietenia macrophylla) fruits, leaves, and branches in shaping the outcomes. The importance of this discovery lies in its contribution to an enhanced comprehension of the overall effects of biochar on the variables explored in our investigation. Notably, the positive changes observed in height, number of leaves, and width of leaves in okra plants further support the premise that the incorporation of biochar improves soil quality. These findings provide valuable insights for agricultural practices, suggesting that biochar derived from Mahogany (Swietenia macrophylla) fruits, leaves, and branches holds promise as a sustainable soil amendment with positive implications for plant growth. The statistical results from multivariate tests serve to solidify the conclusion that biochar plays a pivotal role in driving the observed outcomes in our study. In essence, this research not only sheds light on the potential of mahogany fruit-derived biochar but also emphasizes its significance in fostering healthier soil conditions and, consequently, enhanced plant growth.

Keywords: soil amendment, biochar, mahogany, soil health

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5847 Effects of Temperature and the Use of Bacteriocins on Cross-Contamination from Animal Source Food Processing: A Mathematical Model

Authors: Benjamin Castillo, Luis Pastenes, Fernando Cerdova

Abstract:

The contamination of food by microbial agents is a common problem in the industry, especially regarding the elaboration of animal source products. Incorrect manipulation of the machinery or on the raw materials can cause a decrease in production or an epidemiological outbreak due to intoxication. In order to improve food product quality, different methods have been used to reduce or, at least, to slow down the growth of the pathogens, especially deteriorated, infectious or toxigenic bacteria. These methods are usually carried out under low temperatures and short processing time (abiotic agents), along with the application of antibacterial substances, such as bacteriocins (biotic agents). This, in a controlled and efficient way that fulfills the purpose of bacterial control without damaging the final product. Therefore, the objective of the present study is to design a secondary mathematical model that allows the prediction of both the biotic and abiotic factor impact associated with animal source food processing. In order to accomplish this objective, the authors propose a three-dimensional differential equation model, whose components are: bacterial growth, release, production and artificial incorporation of bacteriocins and changes in pH levels of the medium. These three dimensions are constantly being influenced by the temperature of the medium. Secondly, this model adapts to an idealized situation of cross-contamination animal source food processing, with the study agents being both the animal product and the contact surface. Thirdly, the stochastic simulations and the parametric sensibility analysis are compared with referential data. The main results obtained from the analysis and simulations of the mathematical model were to discover that, although bacterial growth can be stopped in lower temperatures, even lower ones are needed to eradicate it. However, this can be not only expensive, but counterproductive as well in terms of the quality of the raw materials and, on the other hand, higher temperatures accelerate bacterial growth. In other aspects, the use and efficiency of bacteriocins are an effective alternative in the short and medium terms. Moreover, an indicator of bacterial growth is a low-level pH, since lots of deteriorating bacteria are lactic acids. Lastly, the processing times are a secondary agent of concern when the rest of the aforementioned agents are under control. Our main conclusion is that when acclimating a mathematical model within the context of the industrial process, it can generate new tools that predict bacterial contamination, the impact of bacterial inhibition, and processing method times. In addition, the mathematical modeling proposed logistic input of broad application, which can be replicated on non-meat food products, other pathogens or even on contamination by crossed contact of allergen foods.

Keywords: bacteriocins, cross-contamination, mathematical model, temperature

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5846 Comparison of Transforming Growth Factor-β1 Levels in the Human Gingival Sulcus during Canine Retraction Using Elastic Chain and Closed Coil Spring

Authors: Sri Suparwitri

Abstract:

When an orthodontic force is applied to a tooth, an inflammatory response is initiated then lead to bone remodeling process, and the process accommodates tooth movement. One of cytokine that plays a prominent role in bone remodeling process was transforming growth factor-beta 1 (TGF-β1). The purpose of this study was to identify and compare changes of TGF-β1 in human gingival crevicular fluid during canine retraction using elastic chain and closed coil spring. Ten patients (mean age 20.7 ± 2.9 years) participated. The patients were entering the space closure phase of fixed orthodontic treatment. An upper canine of each patient was retracted using elastic chain, and the contralateral canine was retracted using closed coil spring. Gingival crevicular fluid samples were collected from the canine teeth before and 7 days after the force was applied. Transforming growth factor-beta 1 was determined by enzyme-linked immunosorbent assay (ELISA). The concentrations of TGF-β1 at 7 days were significantly higher compared to before canine retraction in both groups. In the evaluation of between-group difference, before retraction, the difference was insignificant, whereas at 7 days significantly higher values were determined in the closed coil spring group compared to elastic chain group. The result suggests that TGF-β1 is associated with the bone remodeling that occurs during canine distalization movement. Closed coil spring gave higher TGF-β1 concentrations thus more bone remodeling occurred and may be considered the treatment of choice.

Keywords: closed coil spring, elastic chain, gingival crevicular fluid, TGF-β1

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5845 Management of Municipal Solid Waste in Baghdad, Iraq

Authors: Ayad Sleibi Mustafa, Ahmed Abdulkadhim Mohsin, Layth Noori Ali

Abstract:

The deterioration of solid waste management in Baghdad city is considered as a great challenge in terms of human health and environment. Baghdad city is divided into thirteen districts which are distributed on both Tigris River banks. The west bank is Al-Karkh and the east bank is Al-Rusafa. Municipal Solid Waste Management is one of the most complicated problems facing the environment in Iraq. Population growth led to increase waste production and more load of the waste to the limited capacity infrastructure. The problems of municipal solid waste become more serious after the war in 2003. More waste is disposed in underground landfills in Baghdad with little or no concern for both human health and environment. The results showed that the total annually predicted solid waste is increasing for the period 2015-2030. Municipal solid waste in 2030 will be 6,427,773 tons in Baghdad city according to the population growth rate of 2.4%. This increase is estimated to be approximately 30%.

Keywords: municipal solid waste, solid waste composition and characteristics, Baghdad city, environment, human health

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5844 Study of the Antimicrobial Activity of Aminoreductone against Pathogenic Bacteria in Comparison with Other Antibiotics

Authors: Vu Thu Trang, Lam Xuan Thanh, Samira Sarter, Tomoko Shimamura, Hiroaki Takeuchi  

Abstract:

Antimicrobial activities of aminoreductone (AR), a product formed in the initial stage of Maillard reaction, were screened against pathogenic bacteria. A significant growth inhibition of AR against all 7 isolates (Staphylococcus aureus ATCC® 25923™, Salmonella Typhimurium ATCC® 14028™, Bacillus cereus ATCC® 13061™, Bacillus subtilis ATCC® 11774™, Escherichia coli ATCC® 25922™, Enterococcus faecalis ATCC® 29212™, Listeria innocua ATCC® 33090™) were observed by the standard disc diffusion methods. The inhibition zone for each isolate by AR (2.5 mg) ranged from 15±0 mm to 28.3±0.4 mm in diameter. The minimum inhibitory concentration (MIC) of AR ranging from 20 mM to 26 mM was proven in the seven isolates tested. AR also showed the similar effect of growth inhibition in comparison with antibiotics frequently used for the treatment of infections bacteria, such as amikacin, ciprofloxacin, meropennem, and levofloxacin. The results indicated that foods containing AR are valuable sources of bioactive compounds towards pathogenic bacteria.

Keywords: pathogenic bacteria, aminoreductone, Maillard reaction, antimicrobial activity

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5843 Biosynthesis of Titanium Dioxide Nanoparticles and Their Antibacterial Property

Authors: Prachi Singh

Abstract:

This paper presents a low-cost, eco-friendly and reproducible microbe mediated biosynthesis of TiO2 nanoparticles. TiO2 nanoparticles synthesized using the bacterium, Bacillus subtilis, from titanium as a precursor, were confirmed by TEM analysis. The morphological characteristics state spherical shape, with the size of individual or aggregate nanoparticles, around 30-40 nm. Microbial resistance represents a challenge for the scientific community to develop new bioactive compounds. Here, the antibacterial effect of TiO2 nanoparticles on Escherichia coli was investigated, which was confirmed by CFU (Colony-forming unit). Further, growth curve study of E. coli Hb101 in the presence and absence of TiO2 nanoparticles was done. Optical density decrease was observed with the increase in the concentration of TiO2. It could be attributed to the inactivation of cellular enzymes and DNA by binding to electron-donating groups such as carboxylates, amides, indoles, hydroxyls, thiols, etc. which cause little pores in bacterial cell walls, leading to increased permeability and cell death. This justifies that TiO2 nanoparticles have efficient antibacterial effect and have potential to be used as an antibacterial agent for different purposes.

Keywords: antibacterial effect, CFU, Escherichia coli Hb101, growth curve, TEM, TiO2 nanoparticle, Toxicity, UV-Vis

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5842 Calibration and Validation of the Aquacrop Model for Simulating Growth and Yield of Rain-fed Sesame (Sesamum indicum L.) Under Different Soil Fertility Levels in the Semi-arid Areas of Tigray

Authors: Abadi Berhane, Walelign Worku, Berhanu Abrha, Gebre Hadgu, Tigray

Abstract:

Sesame is an important oilseed crop in Ethiopia; which is the second most exported agricultural commodity next to coffee. However, there is poor soil fertility management and a research-led farming system for the crop. The AquaCrop model was applied as a decision-support tool; which performs a semi-quantitative approach to simulate the yield of crops under different soil fertility levels. The objective of this experiment was to calibrate and validated the AquaCrop model for simulating the growth and yield of sesame under different nitrogen fertilizer levels and to test the performance of the model as a decision-support tool for improved sesame cultivation in the study area. The experiment was laid out as a randomized complete block design (RCBD) in a factorial arrangement in the 2016, 2017, and 2018 main cropping seasons. In this experiment, four nitrogen fertilizer rates; 0, 23, 46, and 69 Kg/ha nitrogen, and three improved varieties (Setit-1, Setit-2, and Humera-1). In the meantime, growth, yield, and yield components of sesame were collected from each treatment. Coefficient of determination (R2), Root mean square error (RMSE), Normalized root mean square error (N-RMSE), Model efficiency (E), and Degree of agreement (D) were used to test the performance of the model. The results indicated that the AquaCrop model successfully simulated soil water content with R2 varying from 0.92 to 0.98, RMSE 6.5 to 13.9 mm, E 0.78 to 0.94, and D 0.95 to 0.99; and the corresponding values for AB also varied from 0.92 to 0.98, 0.33 to 0.54 tons/ha, 0.74 to 0.93, and 0.9 to 0.98, respectively. The results on the canopy cover of sesame also showed that the model acceptably simulated canopy cover with R2 varying from 0.95 to 0.99, and a RMSE of 5.3 to 8.6%. The AquaCrop model was appropriately calibrated to simulate soil water content, canopy cover, aboveground biomass, and sesame yield; the results indicated that the model adequately simulated the growth and yield of sesame under the different nitrogen fertilizer levels. The AquaCrop model might be an important tool for improved soil fertility management and yield enhancement strategies of sesame. Hence, the model might be applied as a decision-support tool in soil fertility management in sesame production.

Keywords: aquacrop model, sesame, normalized water productivity, nitrogen fertilizer

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5841 Effects of Ascophyllum nodosum in Tomato in the Tropical Caribbean Climate: Effects and Molecular Insights into Mechanisms

Authors: Omar Ali, Adesh Ramsubhag, Jayaraj Jayaraman

Abstract:

Seaweed extracts have been reported as plant biostimulants which could be a safer, organic alternative to harsh pesticides. The incentive to use seaweed-based biostimulants is becoming paramount in sustainable agriculture. The current study, therefore, screened a commercial extract of A. nodosum in tomatoes, cultivated in Trinidad to showcase the multiple beneficial effects. Foliar treatment with an A. nodosum commercial extract led to significant increases in fruit yield and a significant reduction of incidence of bacterial spots and early blight diseases under both greenhouse and field conditions. Investigations were carried out to reveal the possible mechanisms of action of this biostimulant through defense enzyme assays and transcriptome profiling via RNA sequencing of tomato. Studies into disease control mechanisms by A. nodosum showed that the extract stimulated the activity of enzymes such as peroxidase, phenylalanine ammonia-lyase, chitinase, polyphenol oxidase, and β-1,3-glucanase. Additionally, the transcriptome survey revealed the upregulation and enrichment of genes responsible for the biosynthesis of growth hormones, defense enzymes, PR proteins and defense-related secondary metabolites, as well as genes involved in the nutrient mobilization, photosynthesis and primary and secondary metabolic pathways. The results of the transcriptome study also demonstrated the cross-talks between growth and defense responses, confirming the bioelicitor and biostimulant value of seaweed extracts in plants. These effects could potentially implicate the benefits of seaweed extract and validate its usage in sustainable crop production.

Keywords: A. nodosum, biostimulants, elicitor, enzymes, growth responses, seaweeds, tomato, transcriptome analysis

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5840 MCD-017: Potential Candidate from the Class of Nitroimidazoles to Treat Tuberculosis

Authors: Gurleen Kour, Mowkshi Khullar, B. K. Chandan, Parvinder Pal Singh, Kushalava Reddy Yumpalla, Gurunadham Munagala, Ram A. Vishwakarma, Zabeer Ahmed

Abstract:

New chemotherapeutic compounds against multidrug-resistant Mycobacterium tuberculosis (Mtb) are urgently needed to combat drug resistance in tuberculosis (TB). Apart from in-vitro potency against the target, physiochemical properties and pharmacokinetic properties play an imperative role in the process of drug discovery. We have identified novel nitroimidazole derivatives with potential activity against mycobacterium tuberculosis. One lead candidates, MCD-017, which showed potent activity against H37Rv strain (MIC=0.5µg/ml) and was further evaluated in the process of drug development. Methods: Basic physicochemical parameters like solubility and lipophilicity (LogP) were evaluated. Thermodynamic solubility was determined in PBS buffer (pH 7.4) using LC/MS-MS. The partition coefficient (Log P) of the compound was determined between octanol and phosphate buffered saline (PBS at pH 7.4) at 25°C by the microscale shake flask method. The compound followed Lipinski’s rule of five, which is predictive of good oral bioavailability and was further evaluated for metabolic stability. In-vitro metabolic stability was determined in rat liver microsomes. The hepatotoxicity of the compound was also determined in HepG2 cell line. In vivo pharmacokinetic profile of the compound after oral dosing was also obtained using balb/c mice. Results: The compound exhibited favorable solubility and lipophilicity. The physical and chemical properties of the compound were made use of as the first determination of drug-like properties. The compound obeyed Lipinski’s rule of five, with molecular weight < 500, number of hydrogen bond donors (HBD) < 5 and number of hydrogen bond acceptors(HBA) not more then 10. The log P of the compound was less than 5 and therefore the compound is predictive of exhibiting good absorption and permeation. Pooled rat liver microsomes were prepared from rat liver homogenate for measuring the metabolic stability. 99% of the compound was not metabolized and remained intact. The compound did not exhibit cytoxicity in hepG2 cells upto 40 µg/ml. The compound revealed good pharmacokinetic profile at a dose of 5mg/kg administered orally with a half life (t1/2) of 1.15 hours, Cmax of 642ng/ml, clearance of 4.84 ml/min/kg and a volume of distribution of 8.05 l/kg. Conclusion : The emergence of multi drug resistance (MDR) and extensively drug resistant (XDR) Tuberculosis emphasize the requirement of novel drugs active against tuberculosis. Thus, the need to evaluate physicochemical and pharmacokinetic properties in the early stages of drug discovery is required to reduce the attrition associated with poor drug exposure. In summary, it can be concluded that MCD-017 may be considered a good candidate for further preclinical and clinical evaluations.

Keywords: mycobacterium tuberculosis, pharmacokinetics, physicochemical properties, hepatotoxicity

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5839 Microfabrication and Non-Invasive Imaging of Porous Osteogenic Structures Using Laser-Assisted Technologies

Authors: Irina Alexandra Paun, Mona Mihailescu, Marian Zamfirescu, Catalin Romeo Luculescu, Adriana Maria Acasandrei, Cosmin Catalin Mustaciosu, Roxana Cristina Popescu, Maria Dinescu

Abstract:

A major concern in bone tissue engineering is to develop complex 3D architectures that mimic the natural cells environment, facilitate the cells growth in a defined manner and allow the flow transport of nutrients and metabolic waste. In particular, porous structures of controlled pore size and positioning are indispensable for growing human-like bone structures. Another concern is to monitor both the structures and the seeded cells with high spatial resolution and without interfering with the cells natural environment. The present approach relies on laser-based technologies employed for fabricating porous biomimetic structures that support the growth of osteoblast-like cells and for their non-invasive 3D imaging. Specifically, the porous structures were built by two photon polymerization –direct writing (2PP_DW) of the commercially available photoresists IL-L780, using the Photonic Professional 3D lithography system. The structures consist of vertical tubes with micrometer-sized heights and diameters, in a honeycomb-like spatial arrangement. These were fabricated by irradiating the IP-L780 photoresist with focused laser pulses with wavelength centered at 780 nm, 120 fs pulse duration and 80 MHz repetition rate. The samples were precisely scanned in 3D by piezo stages. The coarse positioning was done by XY motorized stages. The scanning path was programmed through a writing language (GWL) script developed by Nanoscribe. Following laser irradiation, the unexposed regions of the photoresist were washed out by immersing the samples in the Propylene Glycol Monomethyl Ether Acetate (PGMEA). The porous structures were seeded with osteoblast like MG-63 cells and their osteogenic potential was tested in vitro. The cell-seeded structures were analyzed in 3D using the digital holographic microscopy technique (DHM). DHM is a marker free and high spatial resolution imaging tool, where the hologram acquisition is performed non-invasively i.e. without interfering with the cells natural environment. Following hologram recording, a digital algorithm provided a 3D image of the sample, as well as information about its refractive index, which is correlated with the intracellular content. The axial resolution of the images went down to the nanoscale, while the temporal scales ranged from milliseconds up to hours. The hologram did not involve sample scanning and the whole image was available in one frame recorded going over 200μm field of view. The digital holograms processing provided 3D quantitative information on the porous structures and allowed a quantitative analysis of the cellular response in respect to the porous architectures. The cellular shape and dimensions were found to be influenced by the underlying micro relief. Furthermore, the intracellular content gave evidence on the beneficial role of the porous structures in promoting osteoblast differentiation. In all, the proposed laser-based protocol emerges as a promising tool for the fabrication and non-invasive imaging of porous constructs for bone tissue engineering. Acknowledgments: This work was supported by a grant of the Romanian Authority for Scientific Research and Innovation, CNCS-UEFISCDI, project PN-II-RU-TE-2014-4-2534 (contract 97 from 01/10/2015) and by UEFISCDI PN-II-PT-PCCA no. 6/2012. A part of this work was performed in the CETAL laser facility, supported by the National Program PN 16 47 - LAPLAS IV.

Keywords: biomimetic, holography, laser, osteoblast, two photon polymerization

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