Mechanical properties of carrot fiber - epoxy composite

Interest has largely centered on the use of plant fibers to reinforce plastics, because these fibers are abundant and cheap. Carrot fibers (Curran) have been extracted from carrot, left over from carrot juice manufacture. The fibers of two sizes fine (5

Dielectric and Thermal Properties of Carrot Fibers –Epoxy Composites

Epoxy composites were prepared with two sizes of carrot fibers in different weight percent (10%, 20%, 30% and 40%) by hand lay-up technique. The dielectric constant and dissipation factor (tanä) of pure epoxy resin and composites were measured in a frequency range of 50 Hz to 5 MHz with increase fibers content, dielectric strength(breakdown voltage) and thermal conductivity were evaluated as a function of fiber content. The dielectric constant and dissipation factor values were found to be higher for fiber reinforced system than the pure epoxy. The dielectric strength values decreases and the values of thermal conductivity increases with fibers content

Comparison of Robust and Bayesian Methods for Estimating the Burr Type XII Distribution

This paper compares the robust and E-Bayesian estimations of the shape parameter for Burr XII distribution. BurrXII distribution was already reviewed by many researchers, as this distribution has gained special attention in recent times due to its complete applications, including the reliability field and failure time modeling. Burr distributions include 12 types of functions that produce a variety of probability density forms. We used two loss functions, quadratic, and LINEX with the E-Bayes method. The comparison conducted by simulation technique, and the absolute mean square error was measured to test the estimation methods' preference. In this study, many familiar distributions methods such as Weibull distribution, exponential logistic distribution, generalized logistic distribution, extreme value, and uniform distribution have been discussed accordingly by employing special cases and belonging to Burr distribution family. The current is dealing with the Bayesian method by depending on the parameter c that must be chosen to be close or not far from parameter b to ensure the robustness of the Bayesian estimator. Then the Bayesian expected of the parameter β under a quadratic loss function. It has been compared estimation for Burr-XII distribution by using the mentioned methods. We found many essential points, such as Robust estimates, in all cases, tend to be more efficient than the Bayes estimates. Also, by increasing the sample size, the robust estimates are still better than other estimation methods. When increasing the sample size, we notice a decrease in MAPE, which supports the statistical theory. We recommend using non-parametric methods to estimate Burr XII parameters. Thus, the main conclusion is that the robust process was the best

Pancreatin-Cetyl Pyridinium Chloride Digestion and Decontamination Method; A Novel, Sensitive, Cost-Effective Method for Culturing Mycobacterium tuberculosis

The present study evaluated the performance of newly developed pancreatin-cetylpyridinium chloride (pancreatin-CPC) digestion and decontamination method (DDM) with N-acetyl L-Cysteine-sodium hydroxide (NALC-NaOH) DDM for isolation of Mycobacteria from clinically suspected pulmonary tuberculosis (PTB) patients. For the study, sputum samples (n = 613) obtained from clinically suspected PTB cases were subjected to direct microscopy, pretreatment with NALC-NaOH DDM (reference method), and pancreatin-CPC DDM followed by culture, and the data were analyzed. The direct microscopy illustrated diagnostic accuracies of 60.4% (sensitivity), 99.77% (specificity), 98.9% (positive predictive value) and 88.3% (negative predictive value), respectively (against culture) for the detection of Mycobacterial species. The pancreatin-CPC DDM showed competitive diagnostic accuracies (against NALC-NaOH DDM) of 99.32% (sensitivity), 94.07% (specificity), 85.05% (positive predictive value), and 99.76% (negative predictive value), respectively, for the isolation of Mycobacterial species. In conclusion, pancreatin-CPC DMM was a highly sensitive, technically simple, and cost-effective method, suggesting its competence to substitute the currently used NALC-NaOH DDM

Optimization and molecular identification of novel cellulose degrading bacteria isolated from Egyptian environment

Cellulase producing bacteria were isolated from both soil and ward poultry, using CMC (carboxymethylcellulose) agar medium and screened by iodine method. Cellulase activity of the isolated bacteria was determined by DNS (dinitrosalicylic) acid method. The highly cellulolytic isolates (BTN7A, BTN7B, BMS4 and SA5) were identified on the basis of Gram staining, morphological cultural characteristics, and biochemical tests. They were also identified with 16S rDNA analysis. The phylogenetic analysis of their 16S rDNA sequence data showed that BTN7B has 99% similarity with Anoxybacillus flavithermus, BMS4 has 99% similarity with Bacillus megaterium, SA5 has 99% homology with Bacillus amyloliquefaciens and BTN7A was 99% similar with Bacillus subtilis. Cellulase production by these strains was optimized by controlling different environmental and nutritional factors such as pH, temperature, incubation period, different volumes of media, aeration rate and carbon source. The cellulase specific activity was calculated in each case. In conclusion four highly cellulolytic bacterial strains were isolated and identified and the optimum conditions for each one for cellulase production were determined. These strains could be used for converting plant waste to more useful compounds

Concurrent analysis of bioactive triterpenes oleanolic acid and β-amyrin in antioxidant active fractions of Hibiscus calyphyllus, Hibiscus deflersii and Hibiscus micranthus grown in Saudi Arabia by applying validated HPTLC method

In this study, we developed a validated HPTLC method for concurrent analysis of two natural antioxidant triterpenes, oleanolic acid (OA) and β-amyrin (BA) in the biologically active fractions (petroleum ether, toluene, chloroform, ethyl acetate and n-butanol) of aerial parts of three Hibiscus species (H. calyphyllus, H. deflersii and H. micranthus). The chromatography was conducted on normal HPTLC (ready to use glass-plate coated with silica gel 60 F254) plate with chloroform and methanol (97:3, V/V) used as mobile phase. The derivatization of the developed plate was done with p-anisaldehyde and scanned at λmax = 575 nm. Well resolved and intense peaks of OA and BA were obtained at Rf = 0.36 and 0.57, respectively. The linear regression equation/correlation coefficient (r2) for OA and BA were Y = 6.65x + 553.35/0.994 and Y = 9.177x + 637.23/0.998, respectively in the linearity range of 100–1200 ng/spot indicated good linear relationship. The low values of %RSD for intra-day/inter-day precision of OA (1.45–1.61/1.38–1.59) and BA (1.52–1.57/1.50–1.53) suggested that the method was precise. The recovery/RSD (%) values for OA and BA were found to be 99.21–99.62/1.39–1.95 and 98.75–99.70/1.56–1.80, respectively assures the reasonably good accuracy of the proposed method. Fifteen samples were analyzed to check the content of OA and BA by using the developed HPTLC methods. The content of OA in different samples were found to be 3.87 (HmP) > 1.212 (HcP) > 0.673 (HdC) > 0.493 (HdP) > 0.168 (HdE) > 0.059 (HcC) > 0.015 (HcE) > 0.008 (HmT) µg/mg of the dried weight of extract. However the content of BA was found as: 2.293 (HmP) > 1.852 (HdT) > 0.345 (HdC) > 0.172 (HmT) > 0.041 (HdE) > 0.008 (HcC) µg/mg of the dried weight of extract. Some Hibiscus species fractions exhibited good antioxidant potential like: HcE (IC50 = 17.6 ± 1.8) > HdB (IC50 = 32.16 ± 0.9) > HmP (IC50 = 80.4 ± 4.5) > HmT (IC50 = 99.7 ± 8.2) when compared with ascorbic acid (IC50 = 14.2 ± 0.5), while other fractions exhibited only mild antioxidant capability. The developed HPTLC method can be further exploited for analysis of these markers in the quality assessment of raw material as well as herbal formulations available in the market

Synthesis, Molecular Docking and Preliminary in-Vitro Cytotoxic Evaluation of Some Substituted Tetrahydro-naphthalene (2',3',4',6'-Tetra-O-Acetyl-β-D-Gluco/-Galactopyranosyl) Derivatives

A facile, convenient and high yielding synthesis of novel <em>S</em>-glycosides and <em>N</em>-glycosides incorporating 1,2,3,4-tetrahydronaphthalene and or 1,2-dihydropyridines moieties has been described. The aglycons <strong>2</strong>, <strong>4</strong>, and <strong>7</strong> were coupled with different activated halosugars in the presence of basic and acidic medium. The preliminary <em>in-vitro</em> cytotoxic evaluation<strong> </strong>revealed that compounds <strong>3c</strong>, <strong>3f</strong>, <strong>5c</strong> and <strong>7b</strong> show promising activity. A molecular docking study was performed against tyrosine kinase (TK) (PDB code: 1t46) by Autodock Vina. The docking output was analyzed and some compounds have shown hydrogen bond (H-B) formation with reasonable distances ranged from 2.06 A° to 3.06 A° with Thr 670 and Cys 673 residues found in the specified pocket. No hydrogen bond was observed with either Glu 640 nor Asp 810 residues, as was expected from pdbsum