Search results for: gas chromatography mass spectrometer
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4101

Search results for: gas chromatography mass spectrometer

2511 Hypertension and Obesity: A Cross-National Comparison of BMI and Waist-Height Ratio

Authors: Adam M. Yates, Julie E. Byles

Abstract:

Hypertension has been identified as a prominent co-morbidity of obesity. To improve clinical intervention of hypertension, it is critical to identify metrics that most accurately reflect risk for increased morbidity. Two of the most relevant and accurate measures for increased risk of hypertension due to excess adipose tissue are Body Mass Index (BMI) and Waist-Height Ratio (WHtR). Previous research has examined these measures in cross-national and cross-ethnic studies, but has most often relied on secondary means such as meta-analysis to identify and evaluate the efficacy of individual body mass measures. In this study, we instead use cross-sectional analysis to assess the cross-ethnic discriminative power of BMI and WHtR to predict risk of hypertension. Using the WHO SAGE survey, which collected anthropometric and biometric data from respondents in six middle-income countries (China, Ghana, India, Mexico, Russia, South Africa), we implement logistic regression to examine the discriminative power of measured BMI and WHtR with a known population of hypertensive and non-hypertensive respondents. We control for gender and age to identify whether optimum cut-off points that are adequately sensitive as tests for risk of hypertension may be different between groups. We report results for OR, RR, and ROC curves for each of the six SAGE countries. As seen in existing literature, results demonstrate that both WHtR and BMI are significant predictors of hypertension (p < .01). For these six countries, we find that cut-off points for WHtR may be dependent upon gender, age and ethnicity. While an optimum omnibus cut-point for WHtR may be 0.55, results also suggest that the gender and age relationship with WHtR may warrant the development of individual cut-offs to optimize health outcomes. Trends through multiple countries show that the optimum cut-point for WHtR increases with age while the area under the curve (AUROC) decreases for both men and women. Comparison between BMI and WHtR indicate that BMI may remain more robust than WHtR. Implications for public health policy are discussed.

Keywords: hypertension, obesity, Waist-Height ratio, SAGE

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2510 Water Gas Shift Activity of PtBi/CeO₂ Catalysts for Hydrogen Production

Authors: N. Laosiripojana, P. Tepamatr

Abstract:

The influence of bismuth on the water gas shift activities of Pt on ceria was studied. The flow reactor was used to study the activity of the catalysts in temperature range 100-400°C. The feed gas composition contains 5%CO, 10% H₂O and balance N₂. The total flow rate was 100 mL/min. The outlet gas was analyzed by on-line gas chromatography with thermal conductivity detector. The catalytic activities of bimetallic 1%Pt1%Bi/CeO₂ catalyst were greatly enhanced when compared with the activities of monometallic 2%Pt/CeO₂ catalyst. The catalysts were characterized by X-ray diffraction (XRD), Temperature-Programmed Reduction (TPR) and surface area analysis. X-ray diffraction pattern of Pt/CeO₂ and PtBi/CeO₂ indicated slightly shift of diffraction angle when compared with pure ceria. This result was due to strong metal-support interaction between platinum and ceria solid solution, causing conversion of Ce⁴⁺ to larger Ce³⁺. The distortions inside ceria lattice structure generated strain into the oxide lattice and facilitated the formation of oxygen vacancies which help to increase water gas shift performance. The H₂-Temperature Programmed Reduction indicated that the reduction peak of surface oxygen of 1%Pt1%Bi/CeO₂ shifts to lower temperature than that of 2%Pt/CeO₂ causing the enhancement of the water gas shift activity of this catalyst. Pt played an important role in catalyzing the surface reduction of ceria and addition of Bi alter the reduction temperature of surface ceria resulting in the improvement of the water gas shift activity of Pt catalyst.

Keywords: bismuth, platinum, water gas shift, ceria

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2509 Cloning, Expression and Protein Purification of AV1 Gene of Okra Leaf Curl Virus Egyptian Isolate and Genetic Diversity between Whitefly and Different Plant Hosts

Authors: Dalia. G. Aseel

Abstract:

Begomoviruses are economically important plant viruses that infect dicotyledonous plants and exclusively transmitted by the whitefly Bemisia tabaci. Here, replicative form was isolated from Okra, Cotton, Tomato plants and whitefly infected with Begomoviruses. Using coat protein specific primers (AV1), the viral infection was verified with amplicon at 450 bp. The sequence of OLCuV-AV1 gene was recorded and received an accession number (FJ441605) from Genebank. The phylogenetic tree of OLCuV was closely related to Okra leaf curl virus previously isolated from Cameroon and USA with nucleotide sequence identity of 92%. The protein purification was carried out using His-Tag methodology by using Affinity Chromatography. The purified protein was separated on SDS-PAGE analysis and an enriched expected size of band at 30 kDa was observed. Furthermore, RAPD and SDS-PAGE were used to detect genetic variability between different hosts of okra leaf curl virus (OLCuV), cotton leaf curl virus (CLCuV), tomato yellow leaf curl virus (TYLCuV) and the whitefly vector. Finally, the present study would help to understand the relationship between the whitefly and different economical crops in Egypt.

Keywords: okra leaf curl virus, AV1 gene, sequencing, phylogenetic, cloning, purified protein, genetic diversity and viral proteins

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2508 Characterization of the Ignitability and Flame Regression Behaviour of Flame Retarded Natural Fibre Composite Panel

Authors: Timine Suoware, Sylvester Edelugo, Charles Amgbari

Abstract:

Natural fibre composites (NFC) are becoming very attractive especially for automotive interior and non-structural building applications because they are biodegradable, low cost, lightweight and environmentally friendly. NFC are known to release high combustible products during exposure to heat atmosphere and this behaviour has raised concerns to end users. To improve on their fire response, flame retardants (FR) such as aluminium tri-hydroxide (ATH) and ammonium polyphosphate (APP) are incorporated during processing to delay the start and spread of fire. In this paper, APP was modified with Gum Arabic powder (GAP) and synergized with carbon black (CB) to form new FR species. Four FR species at 0, 12, 15 and 18% loading ratio were added to oil palm fibre polyester composite (OPFC) panels as follows; OPFC12%APP-GAP, OPFC15%APP-GAP/CB, OPFC18%ATH/APP-GAP and OPFC18%ATH/APPGAP/CB. The panels were produced using hand lay-up compression moulding and cured at room temperature. Specimens were cut from the panels and these were tested for ignition time (Tig), peak heat released rate (HRRp), average heat release rate (HRRavg), peak mass loss rate (MLRp), residual mass (Rm) and average smoke production rate (SPRavg) using cone calorimeter apparatus as well as the available flame energy (ɸ) in driving the flame using radiant panel flame spread apparatus. From the ignitability data obtained at 50 kW/m2 heat flux (HF), it shows that the hybrid FR modified with APP that is OPFC18%ATH/APP-GAP exhibited superior flame retardancy and the improvement was based on comparison with those without FR which stood at Tig = 20 s, HRRp = 86.6 kW/m2, HRRavg = 55.8 kW/m2, MLRp =0.131 g/s, Rm = 54.6% and SPRavg = 0.05 m2/s representing respectively 17.6%, 67.4%, 62.8%, 50.9%, 565% and 62.5% improvements less than those without FR (OPFC0%). In terms of flame spread, the least flame energy (ɸ) of 0.49 kW2/s3 for OPFC18%ATH/APP-GAP caused early flame regression. This was less than 39.6 kW2/s3 compared to those without FR (OPFC0%). It can be concluded that hybrid FR modified with APP could be useful in the automotive and building industries to delay the start and spread of fire.

Keywords: flame retardant, flame regression, oil palm fibre, composite panel

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2507 Copula Autoregressive Methodology for Simulation of Solar Irradiance and Air Temperature Time Series for Solar Energy Forecasting

Authors: Andres F. Ramirez, Carlos F. Valencia

Abstract:

The increasing interest in renewable energies strategies application and the path for diminishing the use of carbon related energy sources have encouraged the development of novel strategies for integration of solar energy into the electricity network. A correct inclusion of the fluctuating energy output of a photovoltaic (PV) energy system into an electric grid requires improvements in the forecasting and simulation methodologies for solar energy potential, and the understanding not only of the mean value of the series but the associated underlying stochastic process. We present a methodology for synthetic generation of solar irradiance (shortwave flux) and air temperature bivariate time series based on copula functions to represent the cross-dependence and temporal structure of the data. We explore the advantages of using this nonlinear time series method over traditional approaches that use a transformation of the data to normal distributions as an intermediate step. The use of copulas gives flexibility to represent the serial variability of the real data on the simulation and allows having more control on the desired properties of the data. We use discrete zero mass density distributions to assess the nature of solar irradiance, alongside vector generalized linear models for the bivariate time series time dependent distributions. We found that the copula autoregressive methodology used, including the zero mass characteristics of the solar irradiance time series, generates a significant improvement over state of the art strategies. These results will help to better understand the fluctuating nature of solar energy forecasting, the underlying stochastic process, and quantify the potential of a photovoltaic (PV) energy generating system integration into a country electricity network. Experimental analysis and real data application substantiate the usage and convenience of the proposed methodology to forecast solar irradiance time series and solar energy across northern hemisphere, southern hemisphere, and equatorial zones.

Keywords: copula autoregressive, solar irradiance forecasting, solar energy forecasting, time series generation

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2506 Partial Least Square Regression for High-Dimentional and High-Correlated Data

Authors: Mohammed Abdullah Alshahrani

Abstract:

The research focuses on investigating the use of partial least squares (PLS) methodology for addressing challenges associated with high-dimensional correlated data. Recent technological advancements have led to experiments producing data characterized by a large number of variables compared to observations, with substantial inter-variable correlations. Such data patterns are common in chemometrics, where near-infrared (NIR) spectrometer calibrations record chemical absorbance levels across hundreds of wavelengths, and in genomics, where thousands of genomic regions' copy number alterations (CNA) are recorded from cancer patients. PLS serves as a widely used method for analyzing high-dimensional data, functioning as a regression tool in chemometrics and a classification method in genomics. It handles data complexity by creating latent variables (components) from original variables. However, applying PLS can present challenges. The study investigates key areas to address these challenges, including unifying interpretations across three main PLS algorithms and exploring unusual negative shrinkage factors encountered during model fitting. The research presents an alternative approach to addressing the interpretation challenge of predictor weights associated with PLS. Sparse estimation of predictor weights is employed using a penalty function combining a lasso penalty for sparsity and a Cauchy distribution-based penalty to account for variable dependencies. The results demonstrate sparse and grouped weight estimates, aiding interpretation and prediction tasks in genomic data analysis. High-dimensional data scenarios, where predictors outnumber observations, are common in regression analysis applications. Ordinary least squares regression (OLS), the standard method, performs inadequately with high-dimensional and highly correlated data. Copy number alterations (CNA) in key genes have been linked to disease phenotypes, highlighting the importance of accurate classification of gene expression data in bioinformatics and biology using regularized methods like PLS for regression and classification.

Keywords: partial least square regression, genetics data, negative filter factors, high dimensional data, high correlated data

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2505 Heterogeneous and Homogeneous Photocatalytic Degradation of Acid Orange 10 in Aqueous Solution

Authors: Merouani Djilali Redha, F. Abdelmalek, A. A. Addou

Abstract:

Advanced oxidation processes (AOPs) utilizing Homogenous photocatalysis (Fenton and photo-Fenton reactions), and Heterogeneous photocatalyse (TiO2 and ZnO) were investigated for the degradation of commercial azo dye ‘Orange G’ wastewater. Fenton and photo-Fenton experimental conditions were: Hydrogen peroxide concentration (10-2 M), Ferrous ions concentration (5.10-4 M), pH (2.8 – 3), UV lamp power (6 watt). Adding more ferrous ions enhanced the oxidation rate for the H2O2/Fe2+ and UV/H2O2/Fe2+ processes. The optimum catalyst loading was found 2.0 g.L-1 in our case for both catalysts TiO2 and ZnO. A comparative study of the photocatalytic degradation showed that these two catalysts have a comparable reactivity; it follows a pseudo-first-order kinetics. The degradation trends followed the order: UV365/Fenton > UV365/TiO2 > Solar Fenton > Solar TiO2 > Fenton ~UV365/ZnO. Among AOPs, processes using Fenton type reagent are relatively cheap and easy to operate and maintain. Moreover, UV365/Fenton process has been shown as effective in the treatment of OG dye. Dye was degraded following second-order kinetics. The rate constants was 0,041 .10+6 L.M-1.min-1. The degradation was followed by spectrophotometric method, chemical oxygen demand (COD) measures and high performance liquid chromatography analyses (HPLC). Some aromatic and aliphatic degradation compounds were identified. Degradation of Orange G by UV Fenton mechanism was also proposed.

Keywords: AOPs, homogeneous catalysis, heterogeneous catalysis, acid orange 10, hydroxyl radical

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2504 The Effect of System Parameters on the Biogas Production from Poultry Rendering Plant Anaerobic Digesters

Authors: N. Lovanh, J. Loughrin, G. Ruiz-Aguilar

Abstract:

Animal wastes can serve as the feedstock for biogas production (mainly methane) that could be used as alternative energy source. The green energy derived from animal wastes is considered to be carbon neutral and offsetting those generated from fossil fuels. In this study, an evaluation of system parameters on methane production from anaerobic digesters utilizing poultry rendering plant wastewater was carried out. Anaerobic batch reactors and continuous flow system subjected to different operation conditions (i.e., flow rate, temperature, and etc.) containing poultry rendering wastewater were set up to evaluate methane potential from each scenario. Biogas productions were sampled and monitored by gas chromatography and photoacoustic gas analyzer over six months of operation. The results showed that methane productions increased as the temperature increased. However, there is an upper limit to the increase in the temperature on the methane production. Flow rates and type of systems (batch vs. plug-flow regime) also had a major effect on methane production. Constant biogas production was observed in plug-flow system whereas batch system produced biogas quicker and tapering off toward the end of the six-month study. Based on these results, it is paramount to consider operating conditions and system setup in optimizing biogas production from agricultural wastewater.

Keywords: anaerobic digestion, methane, poultry rendering wastewater, biotechnology

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2503 Effect of Polymer Coated Urea on Nutrient Efficiency and Nitrate Leaching Using Maize and Annual Ryegrass

Authors: Amrei Voelkner, Nils Peters, Thomas Mannheim

Abstract:

The worldwide exponential growth of the population and the simultaneous increasing food production requires the strategic realization of sustainable and improved cultivation systems to ensure the fertility of arable land and to guarantee the food supply for the whole world. To fulfill this target, large quantities of fertilizers have to be applied to the field, but the long-term environmental impacts remain uncertain. Thus, a combined system would be necessary to increase the nutrient availability for plants while reducing nutrient losses (e.g. NO3- by leaching) to the environment. To enhance the nutrient efficiency, polymer coated fertilizer with a controlled release behavior have been developed. This kind of fertilizer ensures a delayed release of nutrients to synchronize the nutrient supply with the demand of different crops. In the last decades, research focused primarily on semi-permeable polyurethane coatings, which remain in the soil for a long period after the complete solvation of the fertilizer core. Within the implementation of the new European Regulation Directive the replacement of non-degradable synthetic polymers by degradable coatings is necessary. It was, therefore, the objective of this study to develop a total biodegradable polymer (to CO2 and H2O) coating according to ISO 17556 and to compare the retarding effect of the biodegradable coatings with commercially available non-degradable products. To investigate the effect of ten selected coated urea fertilizer on the yield of annual ryegrass and maize, the fresh and dry mass, the percentage of total nitrogen and main nutrients were analyzed in greenhouse experiments in sixfold replications using near-infrared spectroscopy. For the experiments, a homogenized and air-dried loamy sand (Cambic Luvisol) was equipped with a basic fertilization of P, K, Mg and S. To investigate the effect of nitrogen level increase, three levels (80%, 100%, 120%) were established, whereas the impact of CRF granules was determined using a N-level of 100%. Additionally, leaching of NO3- from pots planted with annual ryegrass was examined to evaluate the retention capacity of urea by the polymer coating. For this, leachate from Kick-Brauckmann-Pots was collected daily and analyzed for total nitrogen, NO3- and NH4+ in twofold repetition once a week using near-infrared spectroscopy. We summarize from the results that the coated fertilizer have a clear impact on the yield of annual ryegrass and maize. Compared to the control, an increase of fresh and dry mass could be recognized. Partially, the non-degradable coatings showed a retarding effect for a longer period, which was however reflected by a lower fresh and dry mass. It was ascertained that the percentage of leached-out nitrate could be reduced markedly. As a conclusion, it could be pointed out that the impact of coated fertilizer of all polymer types might contribute to a reduction of negative environmental impacts in addition to their fertilizing effect.

Keywords: biodegradable polymers, coating, enhanced efficiency fertilizers, nitrate leaching

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2502 Feasibility Study of Particle Image Velocimetry in the Muzzle Flow Fields during the Intermediate Ballistic Phase

Authors: Moumen Abdelhafidh, Stribu Bogdan, Laboureur Delphine, Gallant Johan, Hendrick Patrick

Abstract:

This study is part of an ongoing effort to improve the understanding of phenomena occurring during the intermediate ballistic phase, such as muzzle flows. A thorough comprehension of muzzle flow fields is essential for optimizing muzzle device and projectile design. This flow characterization has heretofore been almost entirely limited to local and intrusive measurement techniques such as pressure measurements using pencil probes. Consequently, the body of quantitative experimental data is limited, so is the number of numerical codes validated in this field. The objective of the work presented here is to demonstrate the applicability of the Particle Image Velocimetry (PIV) technique in the challenging environment of the propellant flow of a .300 blackout weapon to provide accurate velocity measurements. The key points of a successful PIV measurement are the selection of the particle tracer, their seeding technique, and their tracking characteristics. We have experimentally investigated the aforementioned points by evaluating the resistance, gas dispersion, laser light reflection as well as the response to a step change across the Mach disk for five different solid tracers using two seeding methods. To this end, an experimental setup has been performed and consisted of a PIV system, the combustion chamber pressure measurement, classical high-speed schlieren visualization, and an aerosol spectrometer. The latter is used to determine the particle size distribution in the muzzle flow. The experimental results demonstrated the ability of PIV to accurately resolve the salient features of the propellant flow, such as the under the expanded jet and vortex rings, as well as the instantaneous velocity field with maximum centreline velocities of more than 1000 m/s. Besides, naturally present unburned particles in the gas and solid ZrO₂ particles with a nominal size of 100 nm, when coated on the propellant powder, are suitable as tracers. However, the TiO₂ particles intended to act as a tracer, surprisingly not only melted but also functioned as a combustion accelerator and decreased the number of particles in the propellant gas.

Keywords: intermediate ballistic, muzzle flow fields, particle image velocimetry, propellant gas, particle size distribution, under expanded jet, solid particle tracers

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2501 Investigation of Bird Impact on Tailplane

Authors: Reza Hedayati, Meysam Jahanbakhshi

Abstract:

The typical airplane stabilizer structures consist of two main similar segments (outer and inner parts), one of them a little larger than the other. In this study, bird impact on four different spots of the stabilizer structure: (a) between two ribs of smaller segment, (b) between two ribs of larger segment, (c) on the rib connecting the two segments, and (d) on a middle rib of the smaller segment, is investigated and their results are compared by means of energy absorption, displacement, and bird’s mass diagrams as well as visible damage induced on the stabilizer structure.

Keywords: airplane, bird strike, LS-DYNA, stabilizer

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2500 Synthesis and Characterization of Cyclic PNC-28 Peptide, Residues 17–26 (ETFSDLWKLL), A Binding Domain of p53

Authors: Deepshikha Verma, V. N. Rajasekharan Pillai

Abstract:

The present study reports the synthesis of cyclic PNC-28 peptides with solid-phase peptide synthesis method. In the first step, we synthesize the linear PNC-28 Peptide and in the second step, we cyclize (N-to-C or head-to-tail cyclization) the linear PNC-28 peptide. The molecular formula of cyclic PNC-28 peptide is C64H88N12O16 and its m/z mass is ≈1233.64. Elemental analysis of cyclic PNC-28 is C, 59.99; H, 6.92; N, 13.12; O, 19.98. The characterization of LC-MS, CD, FT-IR, and 1HNMR has been done to confirm the successful synthesis and cyclization of linear PNC-28 peptides.

Keywords: CD, FTIR, 1HNMR, cyclic peptide

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2499 Isoflavone and Mineral Content in Conventional Commercial Soybean Cultivars and Transgenic Soybean Planted in Minas Gerais, Brazil

Authors: Renata Adriana Labanca, Gabriela Rezende Costa, Nilton de Oliveira Couto e Silva, José Marcos Gontijo Mandarino, Rodrigo Santos Leite, Nilson César Castanheira Guimarães, Roberto Gonçalves Junqueira

Abstract:

The objective of this study was to evaluate the differences in composition between six brands of conventional soybean and six genetically modified cultivars (GM), all of them from Minas Gerais State, Brazil. We focused on the isoflavones profile and mineral content questioning the substantial equivalence between conventional and GM organisms. The statement of compliance label for conventional grains was verified for the presence of genetic modified genes by real time polymerase chain reaction (PCR). We did not detect the presence of the 35S promoter in commercial samples, indicating the absence of transgene insertion. For mineral analysis, we used the method of inductively coupled plasma-optical emission spectrometry (ICP-OES). Isoflavones quantification was performed by high performance liquid chromatography (HPLC). The results showed no statistical difference between the conventional and transgenic soybean groups concerning isoflavone content and mineral composition. The concentration of potassium, the main mineral component of soy, was the highest in conventional soybeans compared to that in GM soy, while GM samples presented the highest concentrations of iron.

Keywords: glycine max, genetically modified organism, bioactive compounds, ICP-OES, HPLC

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2498 Pharmacokinetic Study of Clarithromycin in Human Female of Pakistani Population

Authors: Atifa Mushtaq, Tanweer Khaliq, Hafiz Alam Sher, Asia Farid, Anila Kanwal, Maliha Sarfraz

Abstract:

The study was designed to assess the various pharmacokinetic parameters of a commercially available clarithromycin Tablet (Klaricid® 250 mg Abbot, Pakistan) in plasma sample of healthy adult female volunteers by applying a rapid, sensitive and accurate HPLC-UV analytical method. The human plasma samples were evaluated by using an isocratic High Performance Liquid Chromatography (HPLC) system of Sykam consisted of a pump with a column C18 column (250×4.6mn, 5µm) UV-detector. The mobile phase comprises of potassium dihydrogen phosphate (50 mM, pH 6.8, contained 0.7% triethylamine), methanol and acetonitrile (30:25:45, v/v/v) was delivered with injection volume of 20µL at flow rate of 1 mL/min. The detection was performed at λmax 275 nm. By applying this method, important pharmacokinetic parameters Cmax, Tmax, Area under curve (AUC), half-life (t1/2), , Volume of distribution (Vd) and Clearance (Cl) were measured. The parameters of pharmacokinetics of clarithromycin were calculated by software (APO) pharmacological analysis. Maximum plasma concentrations Cmax 2.78 ±0.33 µg/ml, time to reach maximum concentration tmax 2.82 ± 0.11 h and Area under curve AUC was 20.14 h.µg/ml. The mean ± SD values obtained for the pharmacokinetic parameters showed a significant difference in pharmacokinetic parameters observed in previous literature which emphasizes the need for dose adjustment of clarithromycin in Pakistani population.

Keywords: Pharmacokinetc, Clarothromycin, HPLC, Pakistan

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2497 Mycophenolate-Induced Disseminated TB in a PPD-Negative Patient

Authors: Megan L. Srinivas

Abstract:

Individuals with underlying rheumatologic diseases such as dermatomyositis may not adequately respond to tuberculin (PPD) skin tests, creating false negative results. These illnesses are frequently treated with immunosuppressive therapy making proper identification of TB infection imperative. A 59-year-old Filipino man was diagnosed with dermatomyositis on the basis of rash, electromyography, and muscle biopsy. He was initially treated with IVIG infusions and transitioned to oral prednisone and mycophenolate. The patient’s symptoms improved on this regimen. Six months after starting mycophenolate, the patient began having fevers, night sweats, and productive cough without hemoptysis. He moved from the Philippines 5 years prior to dermatomyositis diagnosis, denied sick contacts, and was PPD negative both at immigration and immediately prior to starting mycophenolate treatment. A third PPD was negative following the onset of these new symptoms. He was treated for community-acquired pneumonia, but symptoms worsened over 10 days and he developed watery diarrhea and a growing non-tender, non-mobile mass on the left side of his neck. A chest x-ray demonstrated a cavitary lesion in right upper lobe suspicious for TB that had not been present one month earlier. Chest CT corroborated this finding also exhibiting necrotic hilar and paratracheal lymphadenopathy. Neck CT demonstrated the left-sided mass as cervical chain lymphadenopathy. Expectorated sputum and stool samples contained acid-fast bacilli (AFB), cultures showing TB bacteria. Fine-needle biopsy of the neck mass (scrofula) also exhibited AFB. An MRI brain showed nodular enhancement suspected to be a tuberculoma. Mycophenolate was discontinued and dermatomyositis treatment was switched to oral prednisone with a 3-day course of IVIG. The patient’s infection showed sensitivity to standard RIPE (rifampin, isoniazid, pyrazinamide, and ethambutol) treatment. Within a week of starting RIPE, the patient’s diarrhea subsided, scrofula diminished, and symptoms significantly improved. By the end of treatment week 3, the patient’s sputum no longer contained AFB; he was removed from isolation, and was discharged to continue RIPE at home. He was discharged on oral prednisone, which effectively addressed his dermatomyositis. This case illustrates the unreliability of PPD tests in patients with long-term inflammatory diseases such as dermatomyositis. Other immunosuppressive therapies (adalimumab, etanercept, and infliximab) have been affiliated with conversion of latent TB to disseminated TB. Mycophenolate is another immunosuppressive agent with similar mechanistic properties. Thus, it is imperative that patients with long-term inflammatory diseases and high-risk TB factors initiating immunosuppressive therapy receive a TB blood test (such as a quantiferon gold assay) prior to the initiation of therapy to ensure that latent TB is unmasked before it can evolve into a disseminated form of the disease.

Keywords: dermatomyositis, immunosuppressant medications, mycophenolate, disseminated tuberculosis

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2496 In vitro And in vivo Anticholinesterase Activity of the Volatile Oil of the Aerial Parts of Ocimum Basilicum L. and O. africanum Lour. Growing in Egypt

Authors: Mariane G. Tadros, Shahira M. Ezzat, Maha M. Salama, Mohamed A. Farag

Abstract:

In this study, the in vitro anticholinesterase activity of the volatile oils of both O. basilicum and O. africanum was investigated and both samples showed significant activity. As a result, the major constituents of the two oils were isolated using several column chromatography. Linalool, 1,8-cineol and eugenol were isolated from the volatile oil of O. basilicum and camphor was isolated from the volatile oil of O. africanum. The anticholinesterase activity of the isolated compounds were also evaluated where 1,8-cineol showed the highest inhibitory activity followed by camphor. To confirm these activities, learning and memory enhancing effects were tested in mice. Memory impairment was induced by scopolamine, a cholinergic muscarinic receptor antagonist. Anti-amnesic effects of both volatile oils and their terpenoids were investigated by the passive avoidance task in mice. We also examined their effects on brain acetylcholinesterase activity. Results showed that scopolamine-induced cognitive dysfunction was significantly attenuated by administration of the volatile oils and their terpenoids, eugenol and camphor, in the passive avoidance task and inhibited brain acetylcholinesterase activity. These results suggest that O. basilicum and O. africanum volatile oils can be good candidates for further studies on Alzheimer’s disease via their acetylcholinesterase inhibitory actions.

Keywords: Ocimum baselicum, Ocimum africanum, GC/MS analysis, anticholinesterase

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2495 Quantitative Assessment of Different Formulations of Antimalarials in Sentinel Sites of India

Authors: Taruna Katyal Arora, Geeta Kumari, Hari Shankar, Neelima Mishra

Abstract:

Substandard and counterfeit antimalarials is a major problem in malaria endemic areas. The availability of counterfeit/ substandard medicines is not only decreasing the efficacy in patients, but it is also one of the contributing factors for developing antimalarial drug resistance. Owing to this, a pilot study was conducted to survey quality of drugs collected from different malaria endemic areas of India. Artesunate+Sulphadoxine-Pyrimethamine (AS+SP), Artemether-Lumefantrine (AL), Chloroquine (CQ) tablets were randomly picked from public health facilities in selected states of India. The quality of antimalarial drugs from these areas was assessed by using Global Pharma Health Fund Minilab test kit. This includes physical/visual inspection and disintegration test. Thin-layer chromatography (TLC) was carried out for semi-quantitative assessment of active pharmaceutical ingredients. A total of 45 brands, out of which 21 were for CQ, 14 for AL and 10 for AS+SP were tested from Uttar Pradesh (U.P.), Mizoram, Meghalaya and Gujrat states. One out of 45 samples showed variable disintegration and retension factor. The variable disintegration and retention factor which would have been due to substandard quality or other factors including storage. However, HPLC analysis confirms standard active pharmaceutical ingredient, but may be due to humid temperature and moisture in storage may account for the observed result.

Keywords: antimalarial medicines, counterfeit, substandard, TLC

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2494 Solitary Fibrous Tumor Presumed to Be a Peripheral Nerve Sheath Tumor Involving Right Branchial Plexus

Authors: Daniela Proca, Yuan Rong, Salvatore Luceno, Jalil Nasibli

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Introduction: Solitary Fibrous Tumors (SFT) have many histologic mimickers and the only way to diagnose it, particularly in an unusual location, such as peripheral nerve trunks, is to use a comprehensive immunohistochemical staining panel. Monoclonal STAT6 immunostain is highly sensitive and specific for SFTs and particularly useful in the diagnosis of difficult SFT cases. Methods: We describe a solitary fibrous tumor (SFT) involving the right branchial plexus in a 66 yo female with 4-year history of slowly growing chest wall mass with recent dysesthesias in fingers 4th and 5th. MRI showed a well-circumscribed heterogenous mass measuring 5.4 x 3.8 x 4.0 cm and encircling peripheral nerves of the branchial plexus; no involvement of the bone or muscle was noted. A biopsy showed a bland spindled and epithelioid proliferation with no significant mitotic activity, no necrosis, and no atypia; peripheral nerve fascicles were encircled by the lesion. The main clinical and pathologic differential diagnosis included peripheral nerve sheath tumor, particularly schwannoma; HE microscopy didn’t show the classic Antoni A and B areas but showed focal subtle nuclear palisading, as well as prominent vessels with hyalinization. Immunohistochemical stains showed focal, weak cytoplasmic S100 positivity in the lesion; CD 34 and Vimentin were strongly and diffusely positive; the neoplastic cells were negative with AE1/AE3, EMA, CD31, SMA, Desmin, Calretinin, HMB-45, Melan A, PAX-8, NSE. The immunohistochemical and histologic pattern was not typical of peripheral nerve sheath tumor. On additional stains, the tumor was positive with STAT-6 and bcl-2 and focally positive with CD99. Given this profile, the final diagnosis was that of a solitary fibrous tumor. Results: NA Conclusion: Very few SFTs involving peripheral nerves and mimicking a peripheral nerve sheath tumor are described in the literature. Although histologically benign on this biopsy, long-term follow-up is required because of the risk of recurrence of these tumors and their uncertain biological behavior.

Keywords: solitary fibrous tumor, pathology, diagnosis, immunohistochemistry

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2493 Conceptual Design of Suction Cup Lifting System

Authors: Mohammed Aijaz

Abstract:

In industries, to transfer fragile materials like glasses, a holding, lifting, and manipulation system are required. In this report, we designed and analysed a suction cup holding, lifting, and manipulation system that is attached to a head plate and must be able to grip/hold securely, the largest glass panel with 3m x 2.5m x 20mm thick with a mass of 115 kg. The system is able to rotate the panel through 180 degrees in the X, Y, and Z axis in any direction from the outer reach of the robotic arm. The structural analysis is performed to verify the structural strength of the suction cup’s head plate system.

Keywords: designing, mechanical, engineering, suction

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2492 Understanding the Heterogeneity of Polycystic Ovarian Syndrome: The Influence of Ethnicity and Body Mass

Authors: Hamza Ikhlaq, Stephen Franks

Abstract:

Background: Polycystic ovarian syndrome (PCOS) is one of the most common endocrine disorders affecting women of reproductive age. The aetiology behind PCOS is poorly understood but influencing ethnic, environmental, and genetic factors have been recognised. However, literature examining the impact of ethnicity is scarce. We hypothesised Body Mass Index (BMI) and ethnicity influence the clinical, metabolic, and biochemical presentations of PCOS, with an interaction between these factors. Methods: A database of 1081 women with PCOS and a control group of 72 women were analysed. BMIs were grouped using the World Health Organisation classification into normal weight, overweight and obese groups. Ethnicities were classified into European, South Asian, and Afro-Caribbean groups. Biochemical and clinical presentations were compared amongst these groups, and statistical analyses were performed to assess significance. Results: This study revealed ethnicity significantly influences biochemical and clinical presentations of PCOS. A greater proportion of South Asian women are impacted by menstrual cycle disturbances and hirsutism than European and Afro-Caribbean women. South Asian and Afro-Caribbean women show greater measures of insulin resistance and weight gain when compared to their European peers. Women with increased BMI are shown to have an increased prevalence of PCOS phenotypes alongside increased levels of insulin resistance and testosterone. Furthermore, significantly different relationships between the waist-hip ratio and measures of insulin and glucose control for Afro-Caribbean women were identified compared to other ethnic groups. Conclusions: The findings of this study show ethnicity significantly influence the phenotypic and biochemical presentations of PCOS, with an interaction between body habitus and ethnicity found. Furthermore, we provide further data on the influences of BMI on the manifestations of PCOS. Therefore, we highlight the need to consider these factors when reviewing diagnostic criteria and delivering clinical care for these groups.

Keywords: PCOS, ethnicity, BMI, clinical

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2491 Expression of Fused Plasmodium falciparum Orotate Phosphoribosyltransferase and Orotidine 5'-Monophosphate Decarboxylase in Escherichia coli

Authors: Waranya Imprasittichai, Patsarawadee Paojinda, Sudaratana R. Krungkrai, Nirianne Marie Q. Palacpac, Toshihiro Horii, Jerapan Krungkrai

Abstract:

Fusion of the last two enzymes in the pyrimidine biosynthetic pathway in the inversed order by having COOH-terminal orotate phosphoribosyltransferase (OPRT) and NH2-terminal orotidine 5'-monophosphate decarboxylase (OMPDC), as OMPDC-OPRT, are described in many organisms. In this study, we constructed gene fusions of Plasmodium falciparum OMPDC-OPRT (1,836 bp) in pTrcHisA vector and expressed as an 6xHis-tag bifunctional protein in three Escherichia coli strains (BL21, Rosetta, TOP10) at 18 °C, 25 °C and 37 °C. The recombinant bifunctional protein was partially purified by Ni-Nitrilotriacetic acid-affinity chromatography. Specific activities of OPRT and OMPDC domains in the bifunctional enzyme expressed in E. coli TOP10 cells were approximately 3-4-fold higher than those in BL21 cells. There were no enzymatic activities when the construct vector expressed in Rosetta cells. Maximal expression of the fused gene was observed at 18 °C and the bifunctional enzyme had specific activities of OPRT and OMPDC domains in a ratio of 1:2. These results provide greater yields and better catalytic activities of the bifunctional OMPDC-OPRT enzyme for further purification and kinetic study.

Keywords: bifunctional enzyme, orotate phosphoribosyltransferase, orotidine 5'-monophosphate decarboxylase, plasmodium falciparum

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2490 Slowness in Architecture: The Pace of Human Engagement with the Built Environment

Authors: Jaidev Tripathy

Abstract:

A human generation’s lifestyle, behaviors, habits, and actions are governed heavily by homogenous mindsets. But the current scenario is witnessing a rapid gap in this homogeneity as a result of an intervention, or rather, the dominance of the digital revolution in the human lifestyle. The current mindset for mass production, employment, multi-tasking, rapid involvement, and stiff competition to stay above the rest has led to a major shift in human consciousness. Architecture, as an entity, is being perceived differently. The screens are replacing the skies. The pace at which operation and evolution is taking place has increased. It is paradoxical, that time seems to be moving faster despite the intention to save time. Parallelly, there is an evident shift in architectural typologies spanning across different generations. The architecture of today is now seems influenced heavily from here and there. Mass production of buildings and over-exploitation of resources giving shape to uninspiring algorithmic designs, ambiguously catering to multiple user groups, has become a prevalent theme. Borrow-and-steal replaces influence, and the diminishing depth in today’s designs reflects a lack of understanding and connection. The digitally dominated world, perceived as an aid to connect and network, is making humans less capable of real-life interactions and understanding. It is not wrong, but it doesn’t seem right either. The engagement level between human beings and the built environment is a concern which surfaces. This leads to a question: Does human engagement drive architecture, or does architecture drive human engagement? This paper attempts to relook at architecture's capacity and its relativity with pace to influence the conscious decisions of a human being. Secondary research, supported with case examples, helps in understanding the translation of human engagement with the built environment through physicality of architecture. The procedure, or theme, is pace and the role of slowness in the context of human behaviors, thus bridging the widening gap between the human race and the architecture themselves give shape to, avoiding a possible future dystopian world.

Keywords: junkspace, pace, perception, slowness

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2489 Multi-Elemental Analysis Using Inductively Coupled Plasma Mass Spectrometry for the Geographical Origin Discrimination of Greek Giant Beans “Gigantes Elefantes”

Authors: Eleni C. Mazarakioti, Anastasios Zotos, Anna-Akrivi Thomatou, Efthimios Kokkotos, Achilleas Kontogeorgos, Athanasios Ladavos, Angelos Patakas

Abstract:

“Gigantes Elefantes” is a particularly dynamic crop of giant beans cultivated in western Macedonia (Greece). This variety of large beans growing in this area and specifically in the regions of Prespes and Kastoria is a protected designation of origin (PDO) species with high nutritional quality. Mislabeling of geographical origin and blending with unidentified samples are common fraudulent practices in Greek food market with financial and possible health consequences. In the last decades, multi-elemental composition analysis has been used in identifying the geographical origin of foods and agricultural products. In an attempt to discriminate the authenticity of Greek beans, multi-elemental analysis (Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, Ge, K, Li, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, Re, Se, Sr, Ta, Ti, Tl, U, V, W, Zn, Zr) was performed by inductively coupled plasma mass spectrometry (ICP-MS) on 320 samples of beans, originated from Greece (Prespes and Kastoria), China and Poland. All samples were collected during the autumn of 2021. The obtained data were analysed by principal component analysis (PCA), an unsupervised statistical method, which allows for to reduce of the dimensionality of the enormous datasets. Statistical analysis revealed a clear separation of beans that had been cultivated in Greece compared with those from China and Poland. An adequate discrimination of geographical origin between bean samples originating from the two Greece regions, Prespes and Kastoria, was also evident. Our results suggest that multi-elemental analysis combined with the appropriate multivariate statistical method could be a useful tool for bean’s geographical authentication. Acknowledgment: This research has been financed by the Public Investment Programme/General Secretariat for Research and Innovation, under the call “YPOERGO 3, code 2018SE01300000: project title: ‘Elaboration and implementation of methodology for authenticity and geographical origin assessment of agricultural products.

Keywords: geographical origin, authenticity, multi-elemental analysis, beans, ICP-MS, PCA

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2488 Study on the Heat Transfer Performance of the Annular Fin under Condensing Conditions

Authors: Abdenour Bourabaa, Malika Fekih, Mohamed Saighi

Abstract:

A numerical investigation of the fin efficiency and temperature distribution of an annular fin under dehumidification has been presented in this paper. The non-homogeneous second order differential equation that describes the temperature distribution from the fin base to the fin tip has been solved using the central finite difference method. The effects of variations in parameters including relative humidity, air temperature, air face velocity on temperature distribution and fin efficiency are investigated and compared with those under fully dry fin conditions. Also, the effect of fin pitch on the dimensionless temperature has been studied.

Keywords: annular fin, dehumidification, fin efficiency, heat and mass transfer, wet fin

Procedia PDF Downloads 474
2487 Response Surface Methodology for the Optimization of Sugar Extraction from Phoenix dactylifera L.

Authors: Lila Boulekbache-Makhlouf, Kahina Djaoud, Myriam Tazarourte, Samir Hadjal, Khodir Madani

Abstract:

In Algeria, important quantities of secondary date variety (Phoenix dactylifera L.) are generated in each campaign; their chemical composition is similar to that of commercial dates. The present work aims to valorize this common date variety (Degla-Beida) which is often poorly exploited. In this context, we tried to prepare syrup from the secondary date variety and to evaluate the effect of conventional extraction (CE) or water bath extraction (WBE) and alternative extraction (microwaves assisted extraction (MAE), and ultrasounds assisted extraction (UAE)) on its total sugar content (TSC), using response surface methodology (RSM). Then, the analysis of individual sugars was performed by high-performance liquid chromatography (HPLC). Maximum predicted TSC recoveries under the optimized conditions for MAE, UAE and CE were 233.248 ± 3.594 g/l, 202.889 ± 5.797 g/l, and 233.535 ± 5.412 g/l, respectively, which were close to the experimental values: 233.796 ± 1.898 g/l; 202.037 ± 3.401 g/l and 234.380 ± 2.425 g/l. HPLC analysis revealed high similarity in the sugar composition of date juices obtained by MAE (60.11% sucrose, 16.64% glucose and 23.25% fructose) and CE (50.78% sucrose, 20.67% glucose and 28.55% fructose), although a large difference was detected for that obtained by UAE (0.00% sucrose, 46.94% glucose and 53.06% fructose). Microwave-assisted extraction was the best method for the preparation of date syrup with an optimal recovery of total sugar content. However, ultrasound-assisted extraction was the best one for the preparation of date syrup with high content of reducing sugars.

Keywords: dates, extraction, RSM, sugars, syrup

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2486 Slope Stabilisation of Highly Fractured Geological Strata Consisting of Mica Schist Layers While Construction of Tunnel Shaft

Authors: Saurabh Sharma

Abstract:

Introduction: The case study deals with the ground stabilisation of Nabi Karim Metro Station in Delhi, India, wherein an extremely complex geology was encountered while excavating the tunnelling shaft for launching Tunnel Boring Machine. The borelog investigation and the Seismic Refraction Technique (SRT) indicated towards the presence of an extremely hard rocky mass from a depth of 3-4 m itself, and accordingly, the Geotechnical Interpretation Report (GIR) concluded the presence of Grade-IV rock from 3m onwards and presence of Grade-III and better rock from 5-6m onwards. Accordingly, it was planned to retain the ground by providing secant piles all around the launching shaft and then excavating the shaft vertically after leaving a berm of 1.5m to prevent secant piles from getting exposed. To retain the side slopes, rock bolting with shotcreting and wire meshing were proposed, which is a normal practice in such strata. However, with the increase in depth of excavation, the rock quality kept on decreasing at an unexpected and surprising pace, with the Grade-III rock mass at 5-6 m converting to conglomerate formation at the depth of 15m. This worsening of geology from high grade rock to slushy conglomerate formation can never be predicted and came as a surprise to even the best geotechnical engineers. Since the excavation had already been cut down vertically to manage the shaft size, the execution was continued with enhanced cautions to stabilise the side slopes. But, when the shaft work was about to finish, a collapse was encountered on one side of the excavation shaft. This collapse was unexpected and surprising since all measures to stabilise the side slopes had been taken after face mapping, and the grid size, diameter, and depth of the rockbolts had already been readjusted to accommodate rock fractures. The above scenario was baffling even to the best geologists and geotechnical engineers, and it was decided that any further slope stabilisation scheme shall have to be designed in such a way to ensure safe completion of works. Accordingly, following revisions to excavation scheme were made: The excavation would be carried while maintaining a slope based on type of soil/rock. The rock bolt type was changed from SN rockbolts to Self Drilling type anchor. The grid size of the bolts changed on real time assessment. the excavation carried out by implementing a ‘Bench Release Approach’. Aggressive Real Time Instrumentation Scheme. Discussion: The above case Study again asserts vitality of correct interpretation of the geological strata and the need of real time revisions of the construction schemes based on the actual site data. The excavation is successfully being done with the above revised scheme, and further details of the Revised Slope Stabilisation Scheme, Instrumentation Schemes, Monitoring results, along with the actual site photographs, shall form the part of the final Paper.

Keywords: unconfined compressive strength (ucs), rock mass rating (rmr), rock bolts, self drilling anchors, face mapping of rock, secant pile, shotcrete

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2485 Ethnopharmacological Analysis of Fermented Herbal Concoctions

Authors: Ishmael Ntlhamu

Abstract:

In Limpopo Province, the use of herbal concoctions is becoming very popular. These concoctions are claimed to be capable of treating ulcers, diabetes, certain STDs, blood cleansing, and many more types of diseases. The aim of this study was to evaluate the phytochemical composition, evaluate the pharmacological effects and consumption safety in herbal concoctions to treat various kinds of ailments in Limpopo. The concoctions were extracted with 80% acetone. Microorganisms in the concoctions were identified using the Vitek 2 compact system. Qualitative phytochemical analysis was determined using standard chemical tests and thin layer chromatography (TLC). Total polyphenol content was quantified. Antioxidant activity was quantified using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay and ferric reducing power. Antimicrobial activities were determined using a broth micro-dilution assay and bioautography. Cell viability assay was used to determine the cytotoxicity. Results showed that concoctions had antioxidant activity. Presence of different phytoconstituents was observed. Isolated microorganisms were identified as Burkholderia pseudomallei, Staphylococcus vitulimus, Enterococcus columbae, Kocuria kristanae, Staphylococcus intermedius, Cryptococcus laurenti. and Burkholderia pseudomallei (highly pathogenic). Therefore, phytochemicals prove that the concoctions can heal as the antimicrobial tests also displayed activity. Moreover, the concoctions did not exhibit cytotoxic effects. However, contaminants raise concerns, not only for consumer safety but also the quality of herbal concoctions available as part of the traditional medicinal practice in Limpopo.

Keywords: antimicrobials, concoctions, cytotoxicity, phytochemicals

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2484 Physical Fitness Normative Reference Values among Lithuanian Primary School Students: Population-Based Cross-Sectional Study

Authors: Brigita Mieziene, Arunas Emeljanovas, Vida Cesnaitiene, Ingunn Fjortoft, Lise Kjonniksen

Abstract:

Background. Health-related physical fitness refers to the favorable health status, i.e. ability to perform daily activities with vigor, as well as capacities that are associated with a low risk for development of chronic diseases and premature death. However, in school-aged children it is constantly declining, while some aspects of fitness declined as much as 50 percent during the last two decades, which prognosticates increasingly earlier onset of health problems, decreasing the quality of life of the population and financial burden for the society. Therefore, the goal of the current study was to indicate nationally representative age- and gender-specific reference values of anthropometric measures, musculoskeletal, motor and cardiorespiratory fitness in Lithuanian primary school children from 6 to 10 years. Methods. The study included 3556 students in total, from 73 randomly selected schools. Ethics approval for research by the Kaunas Regional Ethics Committee (No. BE-2-42) was obtained. Physical fitness was measured by the 9-item test battery, developed by Fjørtoft and colleagues. Height and weight were measured and body mass index calculated. Smoothed centile charts were derived using the LMS method. Results. The numerical age- and gender-specific percentile values (3rd, 10th, 25th, 50th, 75th, 90th, and 97th percentile) for anthropometric measures, musculoskeletal, motor and cardiorespiratory fitness were provided. The equivalent smoothed LMS curves were performed. The study indicated 12.5 percent of overweight and 5 percent of obese children in accordance with international gender and age specific norms of body mass index. This data could be used in clinical and educational settings in order to identify the level of individual physical fitness within its different components.

Keywords: fitness, overweight, primary school children, reference values, smoothed percentile curves

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2483 Mathematical Modeling of Avascular Tumor Growth and Invasion

Authors: Meitham Amereh, Mohsen Akbari, Ben Nadler

Abstract:

Cancer has been recognized as one of the most challenging problems in biology and medicine. Aggressive tumors are a lethal type of cancers characterized by high genomic instability, rapid progression, invasiveness, and therapeutic resistance. Their behavior involves complicated molecular biology and consequential dynamics. Although tremendous effort has been devoted to developing therapeutic approaches, there is still a huge need for new insights into the dark aspects of tumors. As one of the key requirements in better understanding the complex behavior of tumors, mathematical modeling and continuum physics, in particular, play a pivotal role. Mathematical modeling can provide a quantitative prediction on biological processes and help interpret complicated physiological interactions in tumors microenvironment. The pathophysiology of aggressive tumors is strongly affected by the extracellular cues such as stresses produced by mechanical forces between the tumor and the host tissue. During the tumor progression, the growing mass displaces the surrounding extracellular matrix (ECM), and due to the level of tissue stiffness, stress accumulates inside the tumor. The produced stress can influence the tumor by breaking adherent junctions. During this process, the tumor stops the rapid proliferation and begins to remodel its shape to preserve the homeostatic equilibrium state. To reach this, the tumor, in turn, upregulates epithelial to mesenchymal transit-inducing transcription factors (EMT-TFs). These EMT-TFs are involved in various signaling cascades, which are often associated with tumor invasiveness and malignancy. In this work, we modeled the tumor as a growing hyperplastic mass and investigated the effects of mechanical stress from surrounding ECM on tumor invasion. The invasion is modeled as volume-preserving inelastic evolution. In this framework, principal balance laws are considered for tumor mass, linear momentum, and diffusion of nutrients. Also, mechanical interactions between the tumor and ECM is modeled using Ciarlet constitutive strain energy function, and dissipation inequality is utilized to model the volumetric growth rate. System parameters, such as rate of nutrient uptake and cell proliferation, are obtained experimentally. To validate the model, human Glioblastoma multiforme (hGBM) tumor spheroids were incorporated inside Matrigel/Alginate composite hydrogel and was injected into a microfluidic chip to mimic the tumor’s natural microenvironment. The invasion structure was analyzed by imaging the spheroid over time. Also, the expression of transcriptional factors involved in invasion was measured by immune-staining the tumor. The volumetric growth, stress distribution, and inelastic evolution of tumors were predicted by the model. Results showed that the level of invasion is in direct correlation with the level of predicted stress within the tumor. Moreover, the invasion length measured by fluorescent imaging was shown to be related to the inelastic evolution of tumors obtained by the model.

Keywords: cancer, invasion, mathematical modeling, microfluidic chip, tumor spheroids

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2482 Karachi Electric Power Technical and Financial Performance Evaluation after Privatization

Authors: Fawad Azeem

Abstract:

This paper deals with the comparative analysis of Karachi Electric before and after privatization. Technical as well as financial analysis has been done based on the available KE’s stats for last decade. Karachi Electric has evolved as a better entity in terms of its financial and technical achievements. On the other hand, human resources have been seriously affected due to mass firing of employees from the organizations. Study and analysis show that transparent and unbiased privatization practices on institutions like KE that were in serious trouble can upsurge the standards of the institution. Further, for the betterment of the social circle privatization must not affect the employment opportunities.

Keywords: Karachi Electric, power, energy, privatization

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