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

Search results for: in vitro growth

7098 Garlic (Allium sativum) Extract Enhancing Protein Digestive Enzymes and Growth Performance in Marble Goby (Oxyleotris marmorata) Juvenile

Authors: Jaturong Matidtor, Krisna R. Torrissen, Saengtong Pongjareankit, Sudaporn Tongsiri, Jiraporn Rojtinnakorn

Abstract:

Low survival rate has being particular problem in nursery of marble goby juvenile. The aim of this study was to investigate effect of garlic extract on protein digestive pancreatic enzymes, trypsin (T) and chymotrypsin (C). The marble goby were reared with commercial feed mixed garlic extract at concentration of 0 (control), 0.3, 0.5, 1.0, 3.0 and 5.0% (w/w) for 6 weeks. Analysis of the digestive enzymes at 2 and 6 weeks was performed. Growth parameters; weight gain (WG), specific growth rate (SGR) and feed efficiency (FE), were identified. For T, C and T/C at 2 weeks, values of T and T/C ratio of 0.3% (w/w) group showed significant difference (p < 0.05) with the highest values of 17685.64± 11981.77 U/mg protein and of 51.64 ± 27.46 U/mg protein, respectively. For C at 2 weeks, 0% (w/w) group showed the highest values of 16191.76± 2225.56 U/mg protein. Whereas value of T, C and T/C ratio at 6 weeks, there was no significant difference (p > 0.05). For growth performance, it significantly increased in all garlic extract fed groups (0.3-5.0%, w/w), both at 2 and 6 weeks. At 2 weeks, values of WG and SGR of 0.5% (w/w) group showed the highest values of 71.51 ± 1.60%, and 3.85 ± 0.07%, respectively. For FE, 0.3% (w/w) group showed the highest value of 60.21 ± 6.51%. At 6 weeks, it illustrated that all growth parameters of 5.0% (w/w) group were the highest values; WG = 35.06 ± 5.66%, SGR = 2.14 ± 0.30%, and FE = 5.86 ± 0.68%. We suggested that garlic extract could be available for protein digestive enzyme and growth enhancement in marble goby nursery with artificial feed. This result will be high benefit for commercial aquaculture of marble goby.

Keywords: marble goby, nursery, garlic extract, digestive enzyme, growth

Procedia PDF Downloads 328
7097 Role of NaCl and Temperature in Glycerol Mediated Rapid Growth of Silver Nanostructures

Authors: L. R. Shobin, S. Manivannan

Abstract:

One dimensional silver nanowires and nanoparticles gained more interest in developing transparent conducting films, catalysis, biological and chemical sensors. Silver nanostructures can be synthesized by varying reaction conditions such as the precursor concentration, molar ratio of the surfactant, injection speed of silver ions, etc. in the polyol process. However, the reaction proceeds for greater than 2 hours for the formation of silver nanowires. The introduction of etchant in the medium promotes the growth of silver nanowires from silver nanoparticles along the [100] direction. Rapid growth of silver nanowires is accomplished using the Cl- ions from NaCl and polyvinyl pyrrolidone (PVP) as surfactant. The role of Cl- ion was investigated in the growth of the nanostructured silver. Silver nanoparticles (<100 nm) were harvested from glycerol medium in the absence of Cl- ions. Trace amount of Cl- ions (2.5 mM -NaCl) produced the edge joined nanowires of length upto 2 μm and width ranging from 40 to 65 nm. Formation and rapid growth (within 25 minutes) of long, uniform silver nanowires (upto 5 μm) with good yield were realized in the presence of 5 mM NaCl at 200ºC. The growth of nanostructures was monitored by UV-vis-NIR spectroscopy. Scanning and transmission electron microscopes reveal the morphology of the silver nano harvests. The role of temperature in the reduction of silver ions, growth mechanism for nanoparticles, edge joined and straight nanowires will be discussed.

Keywords: silver nanowires, glycerol mediated polyol process, scanning electron microscopy, UV-Vis- NIR spectroscopy, transmission electron microscopy

Procedia PDF Downloads 305
7096 The Fiscal-Monetary Policy and Economic Growth in Algeria: VECM Approach

Authors: K. Bokreta, D. Benanaya

Abstract:

The objective of this study is to examine the relative effectiveness of monetary and fiscal policy in Algeria using the econometric modelling techniques of cointegration and vector error correction modelling to analyse and draw policy inferences. The chosen variables of fiscal policy are government expenditure and net taxes on products, while the effect of monetary policy is presented by the inflation rate and the official exchange rate. From the results, we find that in the long-run, the impact of government expenditures is positive, while the effect of taxes is negative on growth. Additionally, we find that the inflation rate is found to have little effect on GDP per capita but the impact of the exchange rate is insignificant. We conclude that fiscal policy is more powerful then monetary policy in promoting economic growth in Algeria.

Keywords: economic growth, monetary policy, fiscal policy, VECM

Procedia PDF Downloads 315
7095 What Does FDI Inflow Mean for Emerging African Economies?

Authors: E.George, P. Ojeaga, O. Matthew, A. Adekola

Abstract:

Can foreign direct investment (FDI), promote growth in Africa? What does the inflow of investment hold for African emerging economies? Are the determinants of FDI different for different regional blocs in Africa? This study reviews the implication of FDI for different regional blocs in Africa. FDI was found to have a significant effect on growth in North Africa but had no significant effect in East, Southern and West Africa. FDI was also found not to be driving growth in the whole of Africa in a significant manner. The implications of the findings are that even though trade openness seems to be a major factor driving FDI. Poor domestic markets were still preventing many African economies from taking full advantage of the gains from foreign direct investment. The study results could be useful to scholars who study the dynamics surrounding FDI disbursement and strategies on how FDI can drive growth in developing countries.

Keywords: Africa, political economy, FDI, regional policy, markets

Procedia PDF Downloads 578
7094 Effects of Sublethal Concentrations of Parkia biglobosa Pod on Weight Gain in the African Catfish, Clarias gariepinus Juveniles

Authors: M. I. Oshimagye, V. O. Ayuba, P. A. Annune

Abstract:

The effect of Sublethal Concentrations of Parkia biglobosa pod extract on the growth and survival of Clarias gariepinus juveniles (mean weight 32.73g ± 0.0) were investigated under laboratory conditions for 8 weeks using the static renewal and continuous aeration system. Statistical analysis showed that fish exposed to various concentrations had significantly lower (P<0.05) growth rate than the control groups. The reduction in growth was observed to be directly proportional to increase in concentration. However, at 50 mg/L no significant depression in weight was observed.

Keywords: Clarias gariepinus, Parkia biglobosa, pod, weight

Procedia PDF Downloads 502
7093 Government Size and Economic Growth: Testing the Non-Linear Hypothesis for Nigeria

Authors: R. Santos Alimi

Abstract:

Using time-series techniques, this study empirically tested the validity of existing theory which stipulates there is a nonlinear relationship between government size and economic growth; such that government spending is growth-enhancing at low levels but growth-retarding at high levels, with the optimal size occurring somewhere in between. This study employed three estimation equations. First, for the size of government, two measures are considered as follows: (i) share of total expenditures to gross domestic product, (ii) share of recurrent expenditures to gross domestic product. Second, the study adopted real GDP (without government expenditure component), as a variant measure of economic growth other than the real total GDP, in estimating the optimal level of government expenditure. The study is based on annual Nigeria country-level data for the period 1970 to 2012. Estimation results show that the inverted U-shaped curve exists for the two measures of government size and the estimated optimum shares are 19.81% and 10.98%, respectively. Finally, with the adoption of real GDP (without government expenditure component), the optimum government size was found to be 12.58% of GDP. Our analysis shows that the actual share of government spending on average (2000 - 2012) is about 13.4%.This study adds to the literature confirming that the optimal government size exists not only for developed economies but also for developing economy like Nigeria. Thus, a public intervention threshold level that fosters economic growth is a reality; beyond this point economic growth should be left in the hands of the private sector. This finding has a significant implication for the appraisal of government spending and budgetary policy design.

Keywords: public expenditure, economic growth, optimum level, fully modified OLS

Procedia PDF Downloads 423
7092 A Shift in the Structure of Economy and Synergy of University: Developing Potential Through Research and Development Center of SMEs in Jember

Authors: Muhamad Nugraha

Abstract:

Economic growth always correlate positively with the magnitude of the unemployment rate. This is caused by labor which one of important variable to keep growth in the real sector of the region. Meanwhile, the economic structure in districts of Jember showed an increase of economic activity began to shift towards the industrial sector and some other economic sectors, so they have an affects to considerations for policy makers to increase economic growth in Jember as an autonomous region in East Java Province. At the fact, SMEs is among the factors driving economic growth in the region. This is shown by the high amount of SMEs. However, employment in the sector grew slightly slowed. It is caused by a lack of productivity in SMEs. Through the analysis of the transformation of economic structure theory, and the theory of Triple Helix using descriptive analytical method Location Quotient and Shift - Share, found that the results of the economic structure in Jember slowly shifting from the agricultural sector to the industrial sector, because it is dominated by trade sector, hotel and restaurant sector. In addition, SMEs is the potential sector of economic growth in Jember. While to maximizing role and functions of the institution's Research and Development Center of SMEs, there are three points to be known, that are Business Landscape, Business Architecture and Value Added.

Keywords: economic growth, SMEs, labor, Research and Development Center of SMEs

Procedia PDF Downloads 453
7091 Causality between the Construction Industry and the GDP in the United Arab Emirates

Authors: Hasan S. Mahmoud, Salwa M. Beheiry, Vian Ahmed

Abstract:

In light of the repercussions of the 2008 global economic crisis, the response of the United Arab Emirates economy and growth, and the vast construction activities that are undergoing, there is a need to investigate the relationship between construction activities and the Gross Domestic Product (GDP). This study aims to investigate the causality relationship between the construction industry in the United Arab Emirates and the GDP of the country in the last decade. For that, this study will investigate the relationship between the growth of the GDP and the growth of construction activities and their value addition to the economy. To ascertain this relationship, Granger Causality method is used to identify the causality between the time-dependent series.

Keywords: construction value addition, Granger causality, growth of gross domestic product, United Arab Emirates

Procedia PDF Downloads 150
7090 Modeling Exponential Growth Activity Using Technology: A Research with Bachelor of Business Administration Students

Authors: V. Vargas-Alejo, L. E. Montero-Moguel

Abstract:

Understanding the concept of function has been important in mathematics education for many years. In this study, the models built by a group of five business administration and accounting undergraduate students when carrying out a population growth activity are analyzed. The theoretical framework is the Models and Modeling Perspective. The results show how the students included tables, graphics, and algebraic representations in their models. Using technology was useful to interpret, describe, and predict the situation. The first model, the students built to describe the situation, was linear. After that, they modified and refined their ways of thinking; finally, they created exponential growth. Modeling the activity was useful to deep on mathematical concepts such as covariation, rate of change, and exponential function also to differentiate between linear and exponential growth.

Keywords: covariation reasoning, exponential function, modeling, representations

Procedia PDF Downloads 121
7089 Fabrication and Characterization of Folic Acid-Grafted-Thiomer Enveloped Liposomes for Enhanced Oral Bioavailability of Docetaxel

Authors: Farhan Sohail, Gul Shahnaz Irshad Hussain, Shoaib Sarwar, Ibrahim Javed, Zajif Hussain, Akhtar Nadhman

Abstract:

The present study was aimed to develop a hybrid nanocarrier (NC) system with enhanced membrane permeability, bioavailability and targeted delivery of Docetaxel (DTX) in breast cancer. Hybrid NC’s based on folic acid (FA) grafted thiolated chitosan (TCS) enveloped liposomes were prepared with DTX and evaluated in-vitro and in-vivo for their enhanced permeability and bioavailability. Physicochemical characterization of NC’s including particle size, morphology, zeta potential, FTIR, DSC, PXRD, encapsulation efficiency and drug release from NC’s was determined in vitro. Permeation enhancement and p-gp inhibition were performed through everted sac method on freshly excised rat intestine which indicated that permeation was enhanced 5 times as compared to pure DTX and the hybrid NC’s were strongly able to inhibit the p-gp activity as well. In-vitro cytotoxicity and tumor targeting was done using MDA-MB-231 cell line. The stability study of the formulations performed for 3 months showed the improved stability of FA-TCS enveloped liposomes in terms of its particles size, zeta potential and encapsulation efficiency as compared to TCS NP’s and liposomes. The pharmacokinetic study was performed in vivo using rabbits. The oral bioavailability and AUC0-96 was increased 10.07 folds with hybrid NC’s as compared to positive control. Half-life (t1/2) was increased 4 times (58.76 hrs) as compared to positive control (17.72 hrs). Conclusively, it is suggested that FA-TCS enveloped liposomes have strong potential to enhance permeability and bioavailability of hydrophobic drugs after oral administration and tumor targeting.

Keywords: docetaxel, coated liposome, permeation enhancement, oral bioavailability

Procedia PDF Downloads 412
7088 Cryotopic Macroporous Polymeric Matrices for Regenerative Medicine and Tissue Engineering Applications

Authors: Archana Sharma, Vijayashree Nayak, Ashok Kumar

Abstract:

Three-dimensional matrices were fabricated from blend of natural-natural polymers like carrageenan-gelatin and synthetic -natural polymers such as PEG- gelatin (PEG of different molecular weights (2,000 and 6,000) using two different crosslinkers; glutaraldehyde and EDC-NHS by cryogelation technique. Blends represented a feasible approach to design 3-D scaffolds with controllable mechanical, physical and biochemical properties without compromising biocompatibility and biodegradability. These matrices possessed interconnected porous structure, good mechanical strength, biodegradable nature, constant swelling kinetics, ability to withstand high temperature and visco-elastic behavior. Hemocompatibility of cryogel matrices was determined by coagulation assays and hemolytic activity assay which demonstrated that these cryogels have negligible effects on coagulation time and have excellent blood compatibility. In vitro biocompatibility (cell-matrix interaction) inferred good cell adhesion, proliferation, and secretion of ECM on matrices. These matrices provide a microenvironment for the growth, proliferation, differentiation and secretion of ECM of different cell types such as IMR-32, C2C12, Cos-7, rat bone marrow derived MSCs and human bone marrow MSCs. Hoechst 33342 and PI staining also confirmed that the cells were uniformly distributed, adhered and proliferated properly on the cryogel matrix. An ideal scaffold used for tissue engineering application should allow the cells to adhere, proliferate and maintain their functionality. Neurotransmitter analysis has been done which indicated that IMR-32 cells adhered, proliferated and secreted neurotransmitters when they interacted with these matrices which showed restoration of their functionality. The cell-matrix interaction up to molecular level was also evaluated so to check genotoxicity and protein expression profile which indicated that these cryogel matrices are non-genotoxic and maintained biofunctionality of cells growing on these matrices. All these cryogels, when implanted subcutaneously in balb/c mice, showed no adverse systemic or local toxicity effects at implantation site. There was no significant increase in inflammatory cell count has otherwise been observed after scaffold implantation. These cryogels are supermacroporous and this porous structure allows cell infiltration and proliferation of host cells. This showed the integration and presence of infiltrated cells into the cryogel implants. Histological analysis confirmed that the implanted cryogels do not have any adverse effect in spite of host immune system recognition at the site of implantation, on its surrounding tissues and other vital host organs. In vivo biocompatibility study after in vitro biocompatibility analysis has also concluded that these synthesized cryogels act as important biological substitutes, more adaptable and appropriate for transplantation. Thus, these cryogels showed their potential for soft tissue engineering applications.

Keywords: cryogelation, hemocompatibility, in vitro biocompatibility, in vivo biocompatibility, soft tissue engineering applications

Procedia PDF Downloads 228
7087 Mechanical Properties and Microstructures of the Directional Solidified Zn-Al-Cu Alloy

Authors: Mehmet Izzettin Yilmazer, Emin Cadirli

Abstract:

Zn-7wt.%Al-2.96wt.%Cu eutectic alloy was directionally solidified upwards with different temperature gradients (from 6.70 K/mm to 10.67 K/mm) at a constant growth rate (16.4 Km/s) and also different growth rate (from 8.3 micron/s to 166 micron/s) at a constant temperature gradient (10.67 K/mm) using a Bridgman–type growth apparatus.The values of eutectic spacing were measured from longitudinal and transverse sections of the samples. The dependency of microstructures on the G and V were determined with linear regression analysis and experimental equations were found as λl=8.953xVexp-0.49, λt=5.942xVexp-0.42 and λl=0.008xGexp-1.23, λt=0.024xGexp-0.93. The measurements of microhardness of directionally solidified samples were obtained by using a microhardness test device. The dependence of microhardness HV on temperature gradient and growth rate were analyzed. The dependency of microhardness on the G and V were also determined with linear regression analysis as HVl=110.66xVexp0.02, HVt=111.94xVexp0.02 and HVl=69.66xGexp0.17, HVt=68.86xGexp0.18. The experimental results show that the microhardness of the directionally solidified Zn-Al-Cu alloy increases with increasing the growth rate. The results obtained in this work were compared with the previous similar experimental results.

Keywords: directional solidification, eutectic alloys, microstructure, microhardness

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7086 Antibacterial Activity of Nisin: Comparison the Role of Free and Encapsulated Nisin to Control Staphylococcus Aureus Inoculated in Minced Beef

Authors: Zh. Ghasemi, S. Nouri Saeedlou, A. Ghasemi, SL. Nasiri, P. Ayremlou, P. Mahasti

Abstract:

The use of nisin is successfully used as antibacterial agent in various food products. Although the conclusions of the previous studies were that nisin is not very effective in meat environments. The reduced antimicrobial efficacy of nisin when applied in food has been frequently observed. The aim of this study is to evaluate the potential of free and encapsulated nisin to inhibit the growth of staphylococcus aureus in minced beef. The minimum inhibitory concentration (MIC) of nisin is determined against S. aureus using the agar dilution method. Nisin is encapsulated by spray drying, and encapsulation efficiency, mass yield and total solids content values are 47.79%, 61%, and 96.41 respectively. The study in vitro release kinetics shows highest release of nisin from zein capsules is obtained after 72 hour. This work shows that an appropriate delivery system is necessary to obtain desirable effect of nisin in meat and meat product.

Keywords: nisin, encapsulation, Staphylococcus aureus, minced beef, antibacterial activity

Procedia PDF Downloads 293
7085 Induction of Hsp70 and Antioxidant Status in Porcine Granulosa Cells in Response to Deoxynivalenol and Zearalenone Exposure in vitro

Authors: Marcela Capcarova, Adriana Kolesarova, Marina Medvedova, Peter Petruska, Alexander V. Sirotkin

Abstract:

The aim of this study was to determine the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), total antioxidant status (TAS) and accumulation of Hsp70 in porcine ovarian granulosa cells after deoxynivalenol (DON) and zearalenone (ZEA) exposure in vitro. Porcine ovarian granulosa cells were incubated with DON/ZEA administrations as follows: group A (10/10 ng/mL), group B (100/100 ng/mL), group C (1000/1000 ng/mL), and the control group without any additions for 24h. In this study mycotoxins developed stress reaction of porcine ovarian granulosa cells and increased accumulation of Hsp70 what resulted in increasing activities of SOD and GPx in groups with lower doses of mycotoxins. High dose of DON and ZEA had opposite effect on GPx activity than the lower doses. Slight increase in TAS of porcine granulosa cells was observed after mycotoxins exposure. These results contribute towards the understanding of cellular stress and its response.

Keywords: deoxynivalenol, zearalenone, antioxidants, Hsp70, granulosa cells

Procedia PDF Downloads 259
7084 An Application of Vector Error Correction Model to Assess Financial Innovation Impact on Economic Growth of Bangladesh

Authors: Md. Qamruzzaman, Wei Jianguo

Abstract:

Over the decade, it is observed that financial development, through financial innovation, not only accelerated development of efficient and effective financial system but also act as a catalyst in the economic development process. In this study, we try to explore insight about how financial innovation causes economic growth in Bangladesh by using Vector Error Correction Model (VECM) for the period of 1990-2014. Test of Cointegration confirms the existence of a long-run association between financial innovation and economic growth. For investigating directional causality, we apply Granger causality test and estimation explore that long-run growth will be affected by capital flow from non-bank financial institutions and inflation in the economy but changes of growth rate do not have any impact on Capital flow in the economy and level of inflation in long-run. Whereas, growth and Market capitalization, as well as market capitalization and capital flow, confirm feedback hypothesis. Variance decomposition suggests that any innovation in the financial sector can cause GDP variation fluctuation in both long run and short run. Financial innovation promotes efficiency and cost in financial transactions in the financial system, can boost economic development process. The study proposed two policy recommendations for further development. First, innovation friendly financial policy should formulate to encourage adaption and diffusion of financial innovation in the financial system. Second, operation of financial market and capital market should be regulated with implementation of rules and regulation to create conducive environment.

Keywords: financial innovation, economic growth, GDP, financial institution, VECM

Procedia PDF Downloads 275
7083 Response of Chickpea (Cicer arietinum L.) Genotypes to Drought Stress at Different Growth Stages

Authors: Ali. Marjani, M. Farsi, M. Rahimizadeh

Abstract:

Chickpea (Cicer arietinum L.) is one of the important grain legume crops in the world. However, drought stress is a serious threat to chickpea production, and development of drought-resistant varieties is a necessity. Field experiments were conducted to evaluate the response of 8 chickpea genotypes (MCC* 696, 537, 80, 283, 392, 361, 252, 397) and drought stress (S1: non-stress, S2: stress at vegetative growth stage, S3: stress at early bloom, S4: stress at early pod visible) at different growth stages. Experiment was arranged in split plot design with four replications. Difference among the drought stress time was found to be significant for investigated traits except biological yield. Differences were observed for genotypes in flowering time, pod information time, physiological maturation time and yield. Plant height reduced due to drought stress in vegetative growth stage. Stem dry weight reduced due to drought stress in pod visibly. Flowering time, maturation time, pod number, number of seed per plant and yield cause of drought stress in flowering was also reduced. The correlation between yield and number of seed per plant and biological yield was positive. The MCC283 and MCC696 were the high-tolerance genotypes. These results demonstrated that drought stress delayed phonological growth in chickpea and that flowering stage is sensitive.

Keywords: chickpea, drought stress, growth stage, tolerance

Procedia PDF Downloads 264
7082 On Consolidated Predictive Model of the Natural History of Breast Cancer Considering Primary Tumor and Primary Distant Metastases Growth

Authors: Ella Tyuryumina, Alexey Neznanov

Abstract:

Finding algorithms to predict the growth of tumors has piqued the interest of researchers ever since the early days of cancer research. A number of studies were carried out as an attempt to obtain reliable data on the natural history of breast cancer growth. Mathematical modeling can play a very important role in the prognosis of tumor process of breast cancer. However, mathematical models describe primary tumor growth and metastases growth separately. Consequently, we propose a mathematical growth model for primary tumor and primary metastases which may help to improve predicting accuracy of breast cancer progression using an original mathematical model referred to CoM-IV and corresponding software. We are interested in: 1) modelling the whole natural history of primary tumor and primary metastases; 2) developing adequate and precise CoM-IV which reflects relations between PT and MTS; 3) analyzing the CoM-IV scope of application; 4) implementing the model as a software tool. The CoM-IV is based on exponential tumor growth model and consists of a system of determinate nonlinear and linear equations; corresponds to TNM classification. It allows to calculate different growth periods of primary tumor and primary metastases: 1) ‘non-visible period’ for primary tumor; 2) ‘non-visible period’ for primary metastases; 3) ‘visible period’ for primary metastases. The new predictive tool: 1) is a solid foundation to develop future studies of breast cancer models; 2) does not require any expensive diagnostic tests; 3) is the first predictor which makes forecast using only current patient data, the others are based on the additional statistical data. Thus, the CoM-IV model and predictive software: a) detect different growth periods of primary tumor and primary metastases; b) make forecast of the period of primary metastases appearance; c) have higher average prediction accuracy than the other tools; d) can improve forecasts on survival of BC and facilitate optimization of diagnostic tests. The following are calculated by CoM-IV: the number of doublings for ‘nonvisible’ and ‘visible’ growth period of primary metastases; tumor volume doubling time (days) for ‘nonvisible’ and ‘visible’ growth period of primary metastases. The CoM-IV enables, for the first time, to predict the whole natural history of primary tumor and primary metastases growth on each stage (pT1, pT2, pT3, pT4) relying only on primary tumor sizes. Summarizing: a) CoM-IV describes correctly primary tumor and primary distant metastases growth of IV (T1-4N0-3M1) stage with (N1-3) or without regional metastases in lymph nodes (N0); b) facilitates the understanding of the appearance period and manifestation of primary metastases.

Keywords: breast cancer, exponential growth model, mathematical modelling, primary metastases, primary tumor, survival

Procedia PDF Downloads 337
7081 Mechanical Environment of the Aortic Valve and Mechanobiology

Authors: Rania Abdulkareem Aboubakr Mahdaly Ammar

Abstract:

The aortic valve (AV) is a complex mechanical environment that includes flexure, tension, pressure and shear stress forces to blood flow during cardiac cycle. This mechanical environment regulates AV tissue structure by constantly renewing and remodeling the phenotype. In vitro, ex vivo and in vivo studies have explained that pathological states such as hypertension and congenital defects like bicuspid AV ( BAV ) can potentially alter the AV’s mechanical environment, triggering a cascade of remodeling, inflammation and calcification activities in AV tissue. Changes in mechanical environments are first sent by the endothelium that induces changes in the extracellular matrix, and triggers cell differentiation and activation. However, the molecular mechanism of this process is not very well understood. Understanding these mechanisms is critical for the development of effective medical based therapies. Recently, there have been some interesting studies on characterizing the hemodynamics associated with AV, especially in pathologies like BAV, using different experimental and numerical methods. Here, we review the current knowledge of the local AV mechanical environment and its effect on valve biology, focusing on in vitro and ex vivo approaches.

Keywords: aortic valve mechanobiology, bicuspid calcification, pressure stretch, shear stress

Procedia PDF Downloads 369
7080 Estimation of Break Points of Housing Price Growth Rate for Top MSAs in Texas Area

Authors: Hui Wu, Ye Li

Abstract:

Applying the structural break estimation method proposed by Perron and Bai (1998) to the housing price growth rate of top 5 MSAs in the Texas area, this paper estimated the structural break date for the growth rate of housing prices index. As shown in the estimation results, the break dates for each region are quite different, which indicates the heterogeneity of the housing market in response to macroeconomic conditions.

Keywords: structural break, housing prices index, ADF test, linear model

Procedia PDF Downloads 157
7079 Establishments of an Efficient Platform for Genome Editing in Grapevine

Authors: S. Najafi, E. Bertini, M. Pezzotti, G.B. Tornielli, S. Zenoni

Abstract:

Grapevine is an important agricultural fruit crop plant consumed worldwide and with a key role in the global economy. Grapevine is strongly affected by both biotic and abiotic stresses, which impact grape growth at different stages, such as during plant and berry development and pre- and post-harvest, consequently causing significant economic losses. Recently global warming has propelled the anticipation of the onset of berry ripening, determining the reduction of a grape color and increased volatilization of aroma compounds. Climate change could negatively alter the physiological characteristics of the grape and affect the berry and wine quality. Modern plant breeding can provide tools such as genome editing for improving grape resilience traits while maintaining intact the viticultural and oenological quality characteristics of the genotype. This study aims at developing a platform for genome editing application in grapevine plants with the final goal to improve berry quality, biotic, and abiotic resilience traits. We chose to directly deliver ribonucleoproteins (RNP, preassembled Cas protein and guide RNA) into plant protoplasts, and, from these cell structures, regenerate grapevine plants edited in specific selected genes controlling traits of interest. Edited plants regenerated by somatic embryogenesis from protoplasts will then be sequenced and molecularly characterized. Embryogenic calli of Sultana and Shiraz cultivars were initiated from unopened leaves of in-vitro shoot tip cultures and from stamens, respectively. Leaves were placed on NB2 medium while stamens on callus initiation medium (PIV) medium and incubated in the dark at 28 °C for three months. Viable protoplasts, tested by FDA staining, isolated from embryogenic calli were cultured by disc method at 1*105 protoplasts/ml. Mature well-shaped somatic embryos developed directly in the protoplast culture medium two months later and were transferred in the light into to shooting medium for further growth. Regenerated plants were then transferred to the greenhouse; no phenotypic alterations were observed when compared to non in-vitro cultured plants. The performed experiments allowed to established an efficient protocol of embryogenic calli production, protoplast isolation, and regeneration of the whole plant through somatic embryogenesis in both Sultana and Shiraz. Regenerated plants, through direct somatic embryogenesis deriving from a single cell, avoid the risk of chimerism during the regeneration process, therefore improving the genome editing process. As pre-requisite of genome editing, an efficient method for transfection of protoplast by yellow fluorescent protein (YFP) marker genes was also established and experiments of direct delivery of CRISPR–Cas9 ribonucleoproteins (RNPs) in protoplasts to achieve efficient DNA-free targeted mutations are in progress.

Keywords: CRISPR-cas9, plant regeneration, protoplast isolation, Vitis vinifera

Procedia PDF Downloads 154
7078 Assessment of the Physical Quality of Eucalyptus Pellita Seedlings

Authors: Sharifah Insyirah, Noraliza A.

Abstract:

Eucalyptus pellita is a popular species of plantation tree in many nations and regions because of its fast growth and excellent timber qualities. Moreover, Eucalyptus leaves are known as forest harvesting waste with the potential to generate essential oils. Eucalyptus is one of the plants utilized in the pulp and paper industry. This study aims to investigate the impact of two parameters, which are types of fertilizer and polybags (black polybags and transparent polybags), on Eucalyptus growth performance in the nursery. The present investigation was carried out at Main Nursery, Forestry Research Institute Malaysia under agro-climatic and irrigation conditions of the nursery. Twenty seedlings were prepared for this study consisting of two treatments of eco-friendly soil conditioner and NPK (ratio of NPK 8:8:8). Survival and height measurements were collected accordingly. Seedlings without any treatment showed better growth than treatment with soil conditioner or NPK. Seedlings as in C1, shows consistently fastest growth compared to T1 (B) and T2 (SC), and the mortality rates were 0%, 15% and 5%, respectively. The results demonstrated that fertilizer and soil conditioner applied at a younger age of seedlings had less effect on growth performance.

Keywords: eucalyptus pellita, potting media, high quality planting materials, nursery

Procedia PDF Downloads 36
7077 Influence of the Growth Rate on Eutectic Microstructures and Physical Properties of Aluminum–Silicon-Cobalt Alloy

Authors: Aynur Aker, Hasan Kaya

Abstract:

Al-12.6wt.%Si-%2wt.Co alloy was prepared in a graphite crucible under vacuum atmosphere. The samples were directionally solidified upwards with different growth rate at constant temperature gradient using by Bridgman–type growth apparatus. The values of microstructures (λ) was measured from transverse sections of the samples. The microhardness (HV), ultimate tensile strength (σ) and electrical resistivity (ρ) of the directional solidification samples were also measured. Influence of the growth rate and spacings on microhardness, ultimate tensile strength and electrical resistivity were investigated and the relationships between them were experimentally obtained by using regression analysis. The results obtained in present work were compared with the previous similar experimental results obtained for binary and ternary alloys.

Keywords: directional solidification, Al-Si-Co alloy, mechanical properties, electrical properties

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7076 Effect of Single Overload Ratio and Stress Ratio on Fatigue Crack Growth

Authors: M. Benachour, N. Benachour, M. Benguediab

Abstract:

In this investigation, variation of cyclic loading effect on fatigue crack growth is studied. This study is performed on 2024 T351 and 7050-T74 aluminum alloys, used in aeronautical structures. The propagation model used in this study is NASGRO model. In constant amplitude loading (CA), the effect of stress ratio has been investigated. Fatigue life and fatigue crack growth rate were affected by this factor. Results showed an increasing in fatigue crack growth rates (FCGRs) with increasing stress ratio. Variable amplitude loading (VAL) can take many forms i.e with a single overload, overload band etc. The shape of these loads affects strongly the fracture life and FCGRs. The application of a single overload (ORL) decrease the FCGR and increase the delay crack length caused by the formation of a larger plastic zone compared to the plastic zone due without VAL. The fatigue behavior of the both material under single overload has been compared.

Keywords: fatigue crack growth, overload ratio, stress ratio, generalized willenborg model, retardation, al-alloys

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7075 Analysis of Fertilizer Effect in the Tilapia Growth of Mozambique (Oreochromis mossambicus)

Authors: Sérgio Afonso Mulema, Andrés Carrión García, Vicente Ernesto

Abstract:

This paper analyses the effect of fertilizer (organic and inorganic) in the growth of tilapia. An experiment was implemented in the Aquapesca Company of Mozambique; there were considered four different treatments. Each type of fertilizer was applied in two of these treatments; a feed was supplied to the third treatment, and the fourth was taken as control. The weight and length of the tilapia were used as the growth parameters, and to measure the water quality, the physical-chemical parameters were registered. The results show that the weight and length were different for tilapias cultivated in different treatments. These differences were evidenced mainly by organic and feed treatments, where there was the largest and smallest value of these parameters, respectively. In order to prove that these differences were caused only by applied treatment without interference for the aquatic environment, a Fisher discriminant analysis was applied, which confirmed that the treatments were exposed to the same environment condition.

Keywords: fertilizer, tilapia, growth, statistical methods

Procedia PDF Downloads 233
7074 Research on the Role of Platelet Derived Growth Factor Receptor Beta in Promoting Dedifferentiation and Pulmonary Metastasis of Osteosarcoma Under Hypoxic Microenvironment

Authors: Enjie Xu, Zhen Huang, Kunpeng Zhu, Jianping Hu, Xiaolong Ma, Yongjie Wang, Jiazhuang Zhu, Chunlin Zhang

Abstract:

Abstract: Hypoxia and dedifferentiation of osteosarcoma (OS) cells leads to poor prognosis. We plan to identify the role of hypoxia on dedifferentiation and the associated signaling pathways. We performed a sphere formation assay and determined spheroid cells as dedifferentiated cells by detecting stem cell-like markers. RNAi assay was used to explore the expression relationship between hypoxia inducible factor 1 subunit alpha (HIF1A) and platelet derived growth factor receptor beta (PDGFRB). We obtained PDGFRB knockdown and overexpression cells through lentiviral infection experiments and the effects of PDGFRB on cytoskeleton rearrangement and cell adhesion were explored by immunocytochemistry. Wound-healing experiments, transwell assays, and animal trials were employed to investigate the effect of PDGFRB on OS metastasis. Dedifferentiated OS cells were found to exhibit high expression of HIF1A and PDGFRB, and HIF1A promoted the expression of PDGFRB, subsequently activated ras homolog family member A (RhoA), and increased the phosphorylation of myosin light chain (MLC). PDGFRB also enhanced the phosphorylation of focal adhesion kinase (FAK). The OS cell morphology and vinculin distribution were altered by PDGFRB. PDGFRB also promoted cell dedifferentiation and had a significant impact on the metastasis of OS cells both in vitro and in vivo. Our results demonstrated that HIF1A up-regulated PDGFRB under hypoxic conditions, and PDGFRB regulated the actin cytoskeleton by activating RhoA and subsequently phosphorylating MLC, thereby promoting OS dedifferentiation and pulmonary metastasis.

Keywords: osteosarcoma, dedifferentiation, metastasis, cytoskeleton rearrangement, PDGFRB, hypoxia

Procedia PDF Downloads 48
7073 Does "R and D" Investment Drive Economic Growth? Evidence from Africa

Authors: Boopen Seetanah, R. V. Sannassee, Sheereen Fauzel, Robin Nunkoo

Abstract:

The bulk of research on the impact of research and development (R&D) has been carried out in developed economies where the intensity of R&D expenditure has been relatively high and stable for many years. However, there is a paucity of similar studies in developing countries. In this paper, we provide empirical estimates of the impact of R&D investment on economic growth in a developing African economy (Mauritius) where R&D expenditure intensity has been low initially, but rising, albeit moderately in recent years. Using a dynamic time series analysis over the period 1980 to 2014 in a Vector Autoregressive framework, R & D is shown to have a positive and significant effect on the economic progress of the island, although the impact is considerably less when compared to both other ingredients of growth and also to reported elasticities fromdeveloped economies . Interestingly, there is evidence of bicausality between R & D and growth. furthermore, R & D positively impacts on both domestic and foreign investment, suggesting the possibilities of indirect effects.

Keywords: R & D, VECM, Africa, Mauritius

Procedia PDF Downloads 441
7072 Modeling of Crack Growth in Railway Axles under Static Loading

Authors: Zellagui Redouane, Bellaouar Ahmed, Lachi Mohammed

Abstract:

The railway axles are the essential parts in the bogie of train, and its failure creates a big problem in the railway transport; during the work of this parts we noticed a premature deterioration. The aim has been presented a predictive model allowing the identification of the probable causes that are the cause of these premature deterioration. The results are employed for predicting fatigue crack growth in the railway axle, Also we want to present the variation value of stress intensity factor in different positions of elliptical crack tip. The modeling of axle in performed by the SOLID WORKS software and imported into ANSYS.

Keywords: crack growth, static load, railway axle, lifetime

Procedia PDF Downloads 367
7071 The Impact of Public Finance Management on Economic Growth and Development in South Africa

Authors: Zintle Sikhunyana

Abstract:

Management of public finance in many countries such as South Africa is affected by political decisions and by policies around fiscal decentralization amongst the government spheres. Economic success is said to be determined by efficient management of public finance and by the policies or strategies that are implemented to support efficient public finance management. Policymakers focus on pay attention to how economic policies have been implemented and how they are directed into ensuring stable development. This will allow policymakers to address economic challenges through the usage of fiscal policy parameters that are linked to the achieved rate of economic growth and development. Efficient public finance management reduces the likelihood of corruption and corruption is said to have negative effects on economic growth and development. Corruption in public finance refers to an act of using funds for personal benefits. To achieve macroeconomic objectives, governments make use of government expenditure and government expenditure is financed through tax revenue. The main aim of this paper is to investigate the potential impact of public finance management on economic growth and development in South Africa. The secondary data obtained from the South African Reserve Bank (SARB) and World Bank for 1980- 2020 has been utilized to achieve the research objectives. To test the impact of public finance management on economic growth and development, the study will use Seeming Unrelated Regression Equation (SURE) Modelling that allows researchers to model multiple equations with interdependent variables. The advantages of using SUR are that it efficiently allows estimation of relationships between variables by combining information on different equations and SUR test restrictions that involve parameters in different equations. The findings have shown that there is a positive relationship between efficient public finance management and economic growth/development. The findings also show that efficient public finance management has an indirect positive impact on economic growth and development. Corruption has a negative impact on economic growth and development. It results in an efficient allocation of government resources and thereby improves economic growth and development. The study recommends that governments who aim to stimulate economic growth and development should target and strengthen public finance management policies or strategies.

Keywords: corruption, economic growth, economic development, public finance management, fiscal decentralization

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7070 In vitro Establishment and Characterization of Oral Squamous Cell Carcinoma Derived Cancer Stem-Like Cells

Authors: Varsha Salian, Shama Rao, N. Narendra, B. Mohana Kumar

Abstract:

Evolving evidence proposes the existence of a highly tumorigenic subpopulation of undifferentiated, self-renewing cancer stem cells, responsible for exhibiting resistance to conventional anti-cancer therapy, recurrence, metastasis and heterogeneous tumor formation. Importantly, the mechanisms exploited by cancer stem cells to resist chemotherapy are very less understood. Oral squamous cell carcinoma (OSCC) is one of the most regularly diagnosed cancer types in India and is associated commonly with alcohol and tobacco use. Therefore, the isolation and in vitro characterization of cancer stem-like cells from patients with OSCC is a critical step to advance the understanding of the chemoresistance processes and for designing therapeutic strategies. With this, the present study aimed to establish and characterize cancer stem-like cells in vitro from OSCC. The primary cultures of cancer stem-like cell lines were established from the tissue biopsies of patients with clinical evidence of an ulceroproliferative lesion and histopathological confirmation of OSCC. The viability of cells assessed by trypan blue exclusion assay showed more than 95% at passage 1 (P1), P2 and P3. Replication rate was performed by plating cells in 12-well plate and counting them at various time points of culture. Cells had a more marked proliferative activity and the average doubling time was less than 20 hrs. After being cultured for 10 to 14 days, cancer stem-like cells gradually aggregated and formed sphere-like bodies. More spheroid bodies were observed when cultured in DMEM/F-12 under low serum conditions. Interestingly, cells with higher proliferative activity had a tendency to form more sphere-like bodies. Expression of specific markers, including membrane proteins or cell enzymes, such as CD24, CD29, CD44, CD133, and aldehyde dehydrogenase 1 (ALDH1) is being explored for further characterization of cancer stem-like cells. To summarize the findings, the establishment of OSCC derived cancer stem-like cells may provide scope for better understanding the cause for recurrence and metastasis in oral epithelial malignancies. Particularly, identification and characterization studies on cancer stem-like cells in Indian population seem to be lacking thus provoking the need for such studies in a population where alcohol consumption and tobacco chewing are major risk habits.

Keywords: cancer stem-like cells, characterization, in vitro, oral squamous cell carcinoma

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7069 Antidiabetic Potential of Pseuduvaria monticola Bark Extract on the Pancreatic Cells, NIT-1 and Type 2 Diabetic Rat Model

Authors: Hairin Taha, Aditya Arya, M. A. Hapipah, A. M. Mustafa

Abstract:

Plants have been an important source of medicine since ancient times. Pseuduvaria monticola is a rare montane forest species from the Annonaceae family. Traditionally, the plant was used to cure symptoms of fever, inflammation, stomach-ache and also to reduce the elevated levels of blood glucose. Scientifically, we have evaluated the antidiabetic potential of the Pseuduvaria monticola bark methanolic extract on certain in vitro cell based assays, followed by in vivo study. Results from in vitro models displayed PMm upregulated glucose uptake and insulin secretion in mouse pancreatic β-cells. In vivo study demonstrated the PMm down-regulated hyperglycaemia, oxidative stress and elevated levels of pro-inflammatory cytokines in type 2 diabetic rat models. Altogether, the study revealed that Pseuduvaria monticola might be used as a potential candidate for the management of type 2 diabetes and its related complications.

Keywords: type 2 diabetes, Pseuduvaria monticola, insulin secretion, glucose uptake

Procedia PDF Downloads 442