Search results for: molecular cytogenetics
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2067

Search results for: molecular cytogenetics

1047 Phylogenetic Analysis and a Review of the History of the Accidental Phytoplankter, Phaeodactylum tricornutum Bohlin (Bacillariophyta)

Authors: Jamal S. M. Sabir, Edward C. Theriot, Schonna R. Manning, Abdulrahman L. Al-Malki, Mohammad, Mumdooh J. Sabir, Dwight K. Romanovicz, Nahid H. Hajrah, Robert K. Jansen, Matt P. Ashworth

Abstract:

The diatom Phaeodactylum tricornutum has been used as a model for cell biologists and ecologists for over a century. We have incorporated several new raphid pennates into a three-gene phylogenetic dataset (SSU, rbcL, psbC), and recover Gomphonemopsis sp. as sister to P. tricornutum with 100% BS support. This is the first time a close relative has been identified for P. tricornutum with robust statistical support. We test and reject a succession of hypotheses for other relatives. Our molecular data are statistically significantly incongruent with placement of either or both species among the Cymbellales, an order of diatoms with which both have been associated. We believe that further resolution of the phylogenetic position of P. tricornutum will rely more on increased taxon sampling than increased genetic sampling. Gomphonemopsis is a benthic diatom, and its phylogenetic relationship with P. tricornutum is congruent with the hypothesis that P. tricornutum is a benthic diatom with specific adaptations that lead to active recruitment into the plankton. We hypothesize that other benthic diatoms are likely to have similar adaptations and are not merely passively recruited into the plankton.

Keywords: benthic, diatoms; ecology, Phaeodactylum tricornutum, phylogeny, tychoplankton

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1046 A Computational Framework for Load Mediated Patellar Ligaments Damage at the Tropocollagen Level

Authors: Fadi Al Khatib, Raouf Mbarki, Malek Adouni

Abstract:

In various sport and recreational activities, the patellofemoral joint undergoes large forces and moments while accommodating the significant knee joint movement. In doing so, this joint is commonly the source of anterior knee pain related to instability in normal patellar tracking and excessive pressure syndrome. One well-observed explanation of the instability of the normal patellar tracking is the patellofemoral ligaments and patellar tendon damage. Improved knowledge of the damage mechanism mediating ligaments and tendon injuries can be a great help not only in rehabilitation and prevention procedures but also in the design of better reconstruction systems in the management of knee joint disorders. This damage mechanism, specifically due to excessive mechanical loading, has been linked to the micro level of the fibred structure precisely to the tropocollagen molecules and their connection density. We argue defining a clear frame starting from the bottom (micro level) to up (macro level) in the hierarchies of the soft tissue may elucidate the essential underpinning on the state of the ligaments damage. To do so, in this study a multiscale fibril reinforced hyper elastoplastic Finite Element model that accounts for the synergy between molecular and continuum syntheses was developed to determine the short-term stresses/strains patellofemoral ligaments and tendon response. The plasticity of the proposed model is associated only with the uniaxial deformation of the collagen fibril. The yield strength of the fibril is a function of the cross-link density between tropocollagen molecules, defined here by a density function. This function obtained through a Coarse-graining procedure linking nanoscale collagen features and the tissue level materials properties using molecular dynamics simulations. The hierarchies of the soft tissues were implemented using the rule of mixtures. Thereafter, the model was calibrated using a statistical calibration procedure. The model then implemented into a real structure of patellofemoral ligaments and patellar tendon (OpenKnee) and simulated under realistic loading conditions. With the calibrated material parameters the calculated axial stress lies well with the experimental measurement with a coefficient of determination (R2) equal to 0.91 and 0.92 for the patellofemoral ligaments and the patellar tendon respectively. The ‘best’ prediction of the yielding strength and strain as compared with the reported experimental data yielded when the cross-link density between the tropocollagen molecule of the fibril equal to 5.5 ± 0.5 (patellofemoral ligaments) and 12 (patellar tendon). Damage initiation of the patellofemoral ligaments was located at the femoral insertions while the damage of the patellar tendon happened in the middle of the structure. These predicted finding showed a meaningful correlation between the cross-link density of the tropocollagen molecules and the stiffness of the connective tissues of the extensor mechanism. Also, damage initiation and propagation were documented with this model, which were in satisfactory agreement with earlier observation. To the best of our knowledge, this is the first attempt to model ligaments from the bottom up, predicted depending to the tropocollagen cross-link density. This approach appears more meaningful towards a realistic simulation of a damaging process or repair attempt compared with certain published studies.

Keywords: tropocollagen, multiscale model, fibrils, knee ligaments

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1045 In silico and Toxicity Study of the Combination of Roselle (Hibiscus sabdariffa L.) and Garlic (Allium sativum L.) as Antihypertensive Herbs

Authors: Doni Dermawan

Abstract:

Hypertension is a disease with a high prevalence in Indonesia. The prevalence of hypertension in Indonesia is based on the Basic Health Research (Riskesdas) in 2013 which amounted to 25.8%. Medicinal plants have been widely used to treat hypertension including roselle (Hibiscus sabdariffa L.) and garlic (Allium sativum L.) by a mechanism as angiotensin converting enzyme (ACE) inhibitor. The purpose of this research is to analyze the in silico (molecular studies) of pharmacological effects and toxicity of roselle (Hibiscus sabdariffa L.) and garlic (Allium sativum L.) as well as a combination of both are used as antihypertensive herbs. The results of study showed that roselle (Hibiscus sabdariffa L.) and garlic (Allium sativum L.) have great potential as antihypertensive herbs based on the affinity and stability of active substances to specific receptor with a much better value than a of antihypertensive drugs (lisinopril). Toxicity values determined by the method of AST, ALT and ALP in which the three values obtained indicate the presence of acute toxic effects that need to be considered in determining the dose of the extract of roselle and garlic as antihypertensives.

Keywords: Allium sativum, antihypertensive, Hibiscus sabdariffa, in silico, toxicity

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1044 Studying the Anti-Cancer Effects of Thymoquinone on Tumor Cells Through Natural Killer Cells Activity

Authors: Nouf A. Aldarmahi, Nesrin I. Tarbiah, Nuha A. Alkhattabi, Huda F. Alshaibi

Abstract:

Nigella sativa which is known as dark cumin is a well-known example for a widely applicable herbal medicine. Nigella sativa can be effective in a variety of diseases such as hypertension, diabetes, bronchitis, gastrointestinal upset, and cancer. The anticancer effect of Nigella sativa appeared to be mediated by immune-modulatory effect through stimulating human natural killer (NK) cells. This is a type of lymphocytes which is part of the innate immunity, also known as the first line of defense in the body against pathogens. This study investigated the effect of thymoquinone as a major component of Nigella sativa on the molecular cytotoxic pathway of NK cell and the role of thymoquinone therapeutic effect on NK cells. NK cells were cultured with breast tumor cells in different ways and cultured media was collected and the concentration of perforin, granzyme B and interferon-α were measured by ELISA. The cytotoxic effect of NK cells on breast tumor cells was enhanced in the presence of thymoquinone, with increased activity of perforin in NK cells. This improved anticancer effect of thymoquinone on breast cancer cells.

Keywords: breast cancer, cancer cells, natural killer cells, thymoquinone

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1043 Phosphoproteomic Analysis of the Response of Rice Leaves to Chitosan under Drought Stress

Authors: Narumon Phaonakrop, Janthima Jaresitthikunchai, Sittiruk Roytrakul, Wasinee Pongprayoon

Abstract:

Chitosan has been proposed as a natural polymer, and it is derived from chitin. The objective of this research was to determine the growth promoting responses induced by chitosan at the molecular physiology level in Khao Dawk Mali 105 (KDML 105) rice (Oryza sativa L.) seedlings under drought stress by adding of 2% polyethylene glycol 4000 (PEG4000) to the nutrient solution and after removal of the drought stress (re-water). Oligomeric chitosan at 40 ppm could enhance shoot fresh weight and shoot dry weight during drought stress and re-water. After 7 days of drought stress and re-water, significant increases in chlorophyll a and chlorophyll b contents in KDML 105 cultivar were observed. The 749 phosphoproteins in rice leaf treated with chitosan could be resolved by phosphoprotein enrichment, tryptic digestion and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. They can be classified into 10 groups. Proteins involved in the metabolic process and biological regulation were upregulated in response to chitosan during drought stress. This work will help us to understand protein phosphorylation relating to chitosan response during drought stress in aromatic rice seedlings.

Keywords: Chitosan, drought, phosphoproteome, rice

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1042 Molecular Characterization and Determination of Bioremediation Potentials of Some Bacteria Isolated from Spent Oil Contaminated Soil Mechanic Workshops in Kaduna Metropolis

Authors: David D. Adams, Ibrahim B. Bello

Abstract:

Spent oil contaminated Soil from ten selected mechanic workshops were investigated for their bacteria and bioremediation potentials. The bacterial isolates were morphologically and molecularly identified as Enterobacter hormaechei, Escherichia coli, Klebsiella pneumoniae, Shigella flexneri , Wesiella cibaria, Lactobacillus planetarium. The singles and a consortium of these bacteria incubated in the minimal salt medium incorporated with 1% engine oil exhibited various biodegradation rates, with the mixed consortium exhibiting the highest for this oil. The gene for the hydrocarbon enzyme Catechol 2, 3 dioxygenase (C2,30) was detected and amplified in Enterobacter hormaechei, Escherichia coli and Shigella flexneri using PCR and Agarose gel electrophoresis. The detection of the (C2,30) enzyme gene in, and the spent oil biodegradation activity exhibited by these bacteria suggest their possible possession of bioremediating potentials for the spent engine oil. It is therefore suggested that a pilot study on the field application of these bacteria for bioremediation and restoration of spent oil polluted environment should be done in mechanic workshops.

Keywords: spent engine oil, pollution, bacteria, enzyme, bioremediation, mechanic workshop

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1041 Allura Red, Sunset Yellow and Amaranth Azo Dyes for Corrosion Inhibition of Mild Steel in 0.5 H₂SO₄ Solutions

Authors: Ashish Kumar Singh, Preeti Tiwari, Shubham Srivastava, Rajiv Prakash, Herman Terryn, Gopal Ji

Abstract:

Corrosion inhibition potential of azo dyes namely Allura red (AR), Sunset Yellow (SY) and Amaranth (AN) have been investigated in 0.5 M H2SO4 solutions by electrochemical impedance spectroscopy (EIS), Tafel polarization curves, linear polarization curves, open circuit potential (ocp) curves, UV-Visible spectroscopy, Fourier Transform Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) techniques. Amaranth dye is found to provide highest corrosion inhibition (90 %) against mild steel corrosion in sulfuric acid solutions among all the tested dyes; while SY and AR dye shows 80% and 78% corrosion inhibition efficiency respectively. The electrochemical measurements and surface morphology analysis reveal that molecular adsorption of dyes at metal acid interface is accountable for inhibition of mild steel corrosion in H2SO4 solutions. The adsorption behavior of dyes has been investigated by various isotherms models, which verifies that it is in accordance with Langmuir isotherm.

Keywords: mild steel, Azo dye, EIS, Langmuir isotherm

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1040 Characterization of Gamma Irradiated PVDF and PVDF/Graphene Oxide Composites by Spectroscopic Techniques

Authors: Juliana V. Pereira, Adriana S. M. Batista, Jefferson P. Nascimento, Clascídia A. Furtado, Luiz O. Faria

Abstract:

The combination of the properties of graphene oxide (OG) and PVDF homopolymer makes their combined composite materials as multifunctional systems with great potential. Knowledge of the molecular structure is essential for better use. In this work, the degradation of PVDF polymer exposed to gamma irradiation in oxygen atmosphere in high dose rate has been studied and compared to degradation of PVDF/OG composites. The samples were irradiated with a Co-60 source at constant dose rate, with doses ranging from 100 kGy to 1,000 kGy. In FTIR data shown that the formation of oxidation products was at the both samples with formation of carbonyl and hydroxyl groups amongst the most prevalent products in the pure PVDF samples. In the other hand, the composites samples exhibit less presence of degradation products with predominant formation of carbonyl groups, these results also seen in the UV-Vis analysis. The results show that the samples of composites may have greater resistance to the irradiation process, since they have less degradation products than pure PVDF samples seen by spectroscopic techniques.

Keywords: gamma irradiation, PVDF, PVDF/OG composites, spectroscopic techniques

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1039 Nanoarchitectures Cu2S Functions as Effective Surface-Enhanced Raman Scattering Substrates for Molecular Detection Application

Authors: Yu-Kuei Hsu, Ying-Chu Chen, Yan-Gu Lin

Abstract:

The hierarchical Cu2S nano structural film is successfully fabricated via an electroplated ZnO nanorod array as a template and subsequently chemical solution process for the growth of Cu2S in the application of surface-enhanced Raman scattering (SERS) detection. The as-grown Cu2S nano structures were thermally treated at temperature of 150-300 oC under nitrogen atmosphere to improve the crystal quality and unexpectedly induce the Cu nano particles on surface of Cu2S. The structure and composition of thermally treated Cu2S nano structures were carefully analyzed by SEM, XRD, XPS, and XAS. Using 4-aminothiophenol (4-ATP) as probing molecules, the SERS experiments showed that the thermally treated Cu2S nano structures exhibit excellent detecting performance, which could be used as active and cost-effective SERS substrate for ultra sensitive detecting. Additionally, this novel hierarchical SERS substrates show good reproducibility and a linear dependence between analyte concentrations and intensities, revealing the advantage of this method for easily scale-up production.

Keywords: cuprous sulfide, copper, nanostructures, surface-enhanced raman scattering

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1038 Enhancing Reused Lubricating Oil Performance Using Novel Ionic Liquids Based on Imidazolium Derivatives

Authors: Mohamed Deyab

Abstract:

The global lubricant additives market size was USD 14.35 billion in 2015. The industry is characterized by increasing additive usage in base oil blending for longer service life and performance. These additives improve the viscosity of oil, act as detergents, defoamers, antioxidants, and antiwear agents. Since additives play a significant role in base oil blending and subsequent formulations as they are critical materials in improving specification and performance of oils. Herein, we report on the synthesis and characterization of three imidazolium derivatives and their application as antioxidants, detergents and antiwear agents. The molecular structure and characterizations of these ionic liquids were confirmed by elemental analysis, FTIR, X-Ray Diffraction (XRD) and 1HNMR spectroscopy. Thermo gravimetric analysis (TGA), is used to study the degradation and thermal stability of the studied base stock samples. It was found that all the prepared ionic liquids additives have excellent power of dispersion and detergency. The ionic liquids as additives to engine oil reduced the friction (38%) and wear volume (76%) of steel balls. The obtained results show that the ionic liquids have an oxidation inhibitor up to 95%.

Keywords: reused lubricating oil, waste, petroleum, ionic liquids

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1037 Theoretical Studies on the Formation Constant, Geometry, Vibrational Frequencies and Electronic Properties Dinuclear Molybdenum Complexes

Authors: Mahboobeh Mohadeszadeh, Behzad Padidaran Moghaddam

Abstract:

In order to measuring dinuclear molybdenum complexes formation constant First,the reactants and the products were optimized separately and then, their frequencies were measured. In next level , with using Hartree-fock (HF) and density functional theory (DFT) methods ,Theoretical studies on the geometrical parameters, electronic properties and vibrational frequencies of dinuclear molybdenum complexes [C40H44Mo2N2O20] were investigated . These calculations were performed with the B3LYP, BPV86, B3PW91 and HF theoretical method using the LANL2DZ (for Mo’s) + 6-311G (for others) basis sets. To estimate the error rate between theoretical data and experimental data, RSquare , SError and RMS values that according with the theoretical and experimental parameters found out DFT methods has more integration with experimental data compare to HF methods. In addition, through electron specification of compounds, the percentage of atomic orbital’s attendance in making molecular orbital’s, atoms electrical charge, the sustainable energy resulting and also HOMO and LUMO orbital’s energy achieved.

Keywords: geometrical parameters, hydrogen bonding, electronic properties, vibrational frequencies

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1036 Applications of Nonlinear Models to Measure and Predict Thermo Physical Properties of Binary Liquid Mixtures1, 4 Dioxane with Bromo Benzene at Various Temperatures

Authors: R. Ramesh, M. Y. M. Yunus, K. Ramesh

Abstract:

The study conducted in this research are Viscosities, η, and Densities ,ρ, of 1, 4-dioxane with Bromobenzene at different mole fractions and various temperatures in the atmospheric pressure condition. From experimentations excess volumes, VE, and deviations in viscosities, Δη, of mixtures at infinite dilutions have been obtained. The measured systems exhibited positive values of VmE and negative values of Δη. The binary mixture 1, 4 dioxane + Bromobenzene show positive VE and negative Δη with increasing temperatures. The outcomes clearly indicate that weak interactions present in mixture. It is mainly because of number and position of methyl groups exist in these aromatic hydrocarbons. These measured data tailored to the nonlinear models to derive the binary coefficients. Standard deviations have been considered between the fitted outcomes and the calculated data is helpful deliberate mixing behavior of the binary mixtures. It can conclude that in our cases, the data found with the values correlated by the corresponding models very well. The molecular interactions existing between the components and comparison of liquid mixtures were also discussed.

Keywords: 1, 4 dioxane, bromobenzene, density, excess molar volume

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1035 Liquid Crystal Elastomers as Light-Driven Star-Shaped Microgripper

Authors: Indraj Singh, Xuan Lee, Yu-Chieh Cheng

Abstract:

Scientists are very keen on biomimetic research that mimics biological species to micro-robotic devices with the novel functionalities and accessibility. The source of inspiration is the complexity, sophistication, and intelligence of the biological systems. In this work, we design a light-driven star-shaped microgripper, an autonomous soft device which can change the shape under the external stimulus such as light. The design is based on light-responsive Liquid Crystal Elastomers which fabricated onto the polymer coated aligned substrate. The change in shape, controlled by the anisotropicity and the molecular orientation of the Liquid Crystal Elastomer, based on the external stimulus. This artificial star-shaped microgripper is capable of autonomous closure and capable to grab the objects in response to an external stimulus. This external stimulus-responsive materials design, based on soft active smart materials, provides a new approach to autonomous, self-regulating optical systems.

Keywords: liquid crystal elastomers, microgripper, smart materials, robotics

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1034 N₂O₂ Salphen-Like Ligand and Its Pd(II), Ag(I) and Cu(II) Complexes as Potentially Anticancer Agents: Design, Synthesis, Antimicrobial, CT-DNA Binding and Molecular Docking

Authors: Laila H. Abdel-Rahman, Mohamed Shaker S. Adam, Ahmed M. Abu-Dief, Hanan El-Sayed Ahmed

Abstract:

In this investigation, Cu(II), Pd(II) and Ag(I) complexes with the tetra-dentate DSPH Schiff base ligand were synthesized. The DSPH Schiff base and its complexes were characterized by using different physicochemical and spectral analysis. The results revealed that the metal ions coordinated with DSPH ligand through azomethine nitrogen and phenolic oxygen. Cu(II), Pd(II) and Ag(I) complexes are present in a 1:1 molar ratio. Pd(II) and Ag(I) complexes have square planar geometries while, Cu(II) has a distorted octahedral (Oh) geometry. All investigated complexes are nonelectrolytes. The investigated compounds were tested against different strains of bacteria and fungi. Both prepared compounds showed good results of inhibition against the selected pathogenic microorganism. Moreover, the interaction of investigated complexes with CT-DNA was studied via various techniques and the binding modes are mainly intercalative and grooving modes. Operating Environment MOE package was used to do docking studies for the investigated complexes to explore the potential binding mode and energy. Furthermore, the growth inhibitory effect of the investigated compounds was examined on some cancer cells lines.

Keywords: tetradentate, antimicrobial, CT-DNA interaction, docking, anticancer

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1033 Selected Macrophyte Populations Promotes Coupled Nitrification and Denitrification Function in Eutrophic Urban Wetland Ecosystem

Authors: Rupak Kumar Sarma, Ratul Saikia

Abstract:

Macrophytes encompass major functional group in eutrophic wetland ecosystems. As a key functional element of freshwater lakes, they play a crucial role in regulating various wetland biogeochemical cycles, as well as maintain the biodiversity at the ecosystem level. The high carbon-rich underground biomass of macrophyte populations may harbour diverse microbial community having significant potential in maintaining different biogeochemical cycles. The present investigation was designed to study the macrophyte-microbe interaction in coupled nitrification and denitrification, considering Deepor Beel Lake (a Ramsar conservation site) of North East India as a model eutrophic system. Highly eutrophic sites of Deepor Beel were selected based on sediment oxygen demand and inorganic phosphorus and nitrogen (P&N) concentration. Sediment redox potential and depth of the lake was chosen as the benchmark for collecting the plant and sediment samples. The average highest depth in winter (January 2016) and summer (July 2016) were recorded as 20ft (6.096m) and 35ft (10.668m) respectively. Both sampling depth and sampling seasons had the distinct effect on variation in macrophyte community composition. Overall, the dominant macrophytic populations in the lake were Nymphaea alba, Hydrilla verticillata, Utricularia flexuosa, Vallisneria spiralis, Najas indica, Monochoria hastaefolia, Trapa bispinosa, Ipomea fistulosa, Hygrorhiza aristata, Polygonum hydropiper, Eichhornia crassipes and Euryale ferox. There was a distinct correlation in the variation of major sediment physicochemical parameters with change in macrophyte community compositions. Quantitative estimation revealed an almost even accumulation of nitrate and nitrite in the sediment samples dominated by the plant species Eichhornia crassipes, Nymphaea alba, Hydrilla verticillata, Vallisneria spiralis, Euryale ferox and Monochoria hastaefolia, which might have signified a stable nitrification and denitrification process in the sites dominated by the selected aquatic plants. This was further examined by a systematic analysis of microbial populations through culture dependent and independent approach. Culture-dependent bacterial community study revealed the higher population of nitrifiers and denitrifiers in the sediment samples dominated by the six macrophyte species. However, culture-independent study with bacterial 16S rDNA V3-V4 metagenome sequencing revealed the overall similar type of bacterial phylum in all the sediment samples collected during the study. Thus, there might be the possibility of uneven distribution of nitrifying and denitrifying molecular markers among the sediment samples collected during the investigation. The diversity and abundance of the nitrifying and denitrifying molecular markers in the sediment samples are under investigation. Thus, the role of different aquatic plant functional types in microorganism mediated nitrogen cycle coupling could be screened out further from the present initial investigation.

Keywords: denitrification, macrophyte, metagenome, microorganism, nitrification

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1032 Identification and Molecular Characterization of Cryptosporidium Spp. in Pre-Wean Dairy Calves in Mashhad, Northeastern of Iran

Authors: Mohammad Asadpour, Gholamreza Razmi, Gholamreza Mohammadi, Abolghasem Naghibi

Abstract:

Cryptosporidium Spp., protozoan parasites of the phylum Apicomplexa, have a wide spectrum of hosts including humans, domestic animals and wild mammals, birds, reptiles, amphibians and fish. Dairy cattle have been identified in numerous reports as a major source of environmental contamination with this pathogen. In this study, a Polymerase Chain Reaction (PCR), Restriction Fragment Length Polymorphism (RFLP) analysis of the Small-Subunit (SSU) rRNA gene was used to detect and identify Cryptosporidium Spp. in 300 fecal specimens from 1 to 30 days pre-wean calves in 10 farms in Mashhad, Iran. Eighty five (28.3%) and forty five (15%) of the specimens were positive for Cryptosporidium by microscopic and PCR examination respectively. Restriction digestion of the PCR products by VSPI and Ssp1 restriction enzymes and analysis of sequence data revealed the presence of C. parvum, bovine genotype in all isolates. Our findings suggest that cattle can be a source of Cryptosporidial infections for humans and animals in Mashhad area. This is the first published description of Cryptosporidium sub genotyping in Mashhad.

Keywords: cryptosporidium, genotype, dairy calves, 18S rRNA, Mashhad

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1031 Nanostructure and Adhesion of Cement/Polymer Fiber Interfaces

Authors: Faezeh Shalchy

Abstract:

Concrete is the most used materials in the world. It is also one of the most versatile while complex materials which human have used for construction. However, concrete is weak in tension, over the past thirty years many studies were accomplished to improve the tensile properties of concrete (cement-based materials) using a variety of methods. One of the most successful attempts is to use polymeric fibers in the structure of concrete to obtain a composite with high tensile strength and ductility. Understanding the mechanical behavior of fiber reinforced concrete requires the knowledge of the fiber/matrix interfaces at the small scale. In this study, a combination of numerical simulations and experimental techniques have been used to study the nano structure of fiber/matrix interfaces. A new model for calcium-silicate-hydrate (C-S-H)/fiber interfaces is proposed based on Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) analysis. The adhesion energy between the C-S-H gel and 2 different polymeric fibers (polyvinyl alcohol and polypropylene) was numerically studied at the atomistic level since adhesion is one of the key factors in the design of fiber reinforced composites. The mechanisms of adhesion as a function of the nano structure of fiber/matrix interfaces are also studied and discussed.

Keywords: fiber-reinforced concrete, adhesion, molecular modeling

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1030 Biological Activity of Hibiscus sabdariffa Extract

Authors: Chanasit Chaocharoenphat

Abstract:

Hibiscus sabdariffa is a herbal plant that is commonly used for home remedies in Thailand. This study aims to determine the antioxidant activity of polyphenols, as oxidative stress plays a vital role in the development of cancer, and H. sabdariffa was used in this study. The total flavonoids content was determined using the aluminium chloride colourimetric method and expressed as quercetin equivalents (QE)/g and the antioxidant capacity of the flavonoids using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging capacity assays. The IC50 values of H. sabdariffa extract were 167.14 μg/mL ± 0.843 and 77.59 μg/mL ± 0.798, respectively. In the DPPH assay, vitamin C was used as a positive control, whereas Trolox was used as a positive control in the ABTS assay. To summarise, H. sabdariffa extract contains a high concentration of total flavonoids and exhibits potent antioxidant activity. However, additional antioxidant activity assays such as superoxide dismutase (SOD), reactive oxygen species (ROS), and reactive nitrogen species (RNS) scavenging assays and in vitro antioxidant experiments should be carried out to investigate the molecular mechanism of the compound.

Keywords: ABTS assay, antioxidant activity, Gracilaria fisheri, DPPH assays, total flavonoid content

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1029 Retrospective Casenote Audit of Venous Thromboembolism Prophylaxis in Maxillofacial Patients

Authors: Joshua Abraham, Craig Wales

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Abstract—SIGN Guideline 122 recommends that all patients who are admitted to hospital are assessed for venous thromboembolism risk within 24 hours of admission. NHS Greater Glasgow and Clyde provide guidance on this in the form of a proforma. Patients are then subsequently prescribed either thrombo-embolic-deterrent stockings (TEDS)/low molecular weight heparin (LMWH) for the prevention of VTE based on their score. A retrospective casenote audit of a random sample of fifty oncology and trauma inpatients at the QEUH in December 2019 was performed. 90% of patients had a risk assessment conducted as evidenced by a completed proforma. In 78% of these patients, the proforma fully completed. Overall 94% of patients had some for of thromboprophylaxis prescribed in the form of TEDS or LMWH. A lack of 100% compliance against the given standards highlighted potential implications for patient safety, but also medico-legal ramifications for staff. Clinical judgement can only be relied upon if there is written documentation as evidence. Further staff education and the suggestion of a written prompt to the clerk-in documentation will hopefully improve compliance, whilst a repeat audit should demonstrate any improvement.

Keywords: Maxillofacial , Thromboembolism, Thromboprophylaxis , Prescription

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1028 Hypoxia Tolerance, Longevity and Cancer-Resistance in the Mole Rat Spalax – a Liver Transcriptomics Approach

Authors: Hanno Schmidt, Assaf Malik, Anne Bicker, Gesa Poetzsch, Aaron Avivi, Imad Shams, Thomas Hankeln

Abstract:

The blind subterranean mole rat Spalax shows a remarkable tolerance to hypoxia, cancer-resistance and longevity. Unravelling the genomic basis of these adaptations will be important for biomedical applications. RNA-Seq gene expression data were obtained from normoxic and hypoxic Spalax and rat liver tissue. Hypoxic Spalax broadly downregulates genes from major liver function pathways. This energy-saving response is likely a crucial adaptation to low oxygen levels. In contrast, the hypoxiasensitive rat shows massive upregulation of energy metabolism genes. Candidate genes with plausible connections to the mole rat’s phenotype, such as important key genes related to hypoxia-tolerance, DNA damage repair, tumourigenesis and ageing, are substantially higher expressed in Spalax than in rat. Comparative liver transcriptomics highlights the importance of molecular adaptations at the gene regulatory level in Spalax and pinpoints a variety of starting points for subsequent functional studies.

Keywords: cancer, hypoxia, longevity, transcriptomics

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1027 Application and Assessment of Artificial Neural Networks for Biodiesel Iodine Value Prediction

Authors: Raquel M. De sousa, Sofiane Labidi, Allan Kardec D. Barros, Alex O. Barradas Filho, Aldalea L. B. Marques

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Several parameters are established in order to measure biodiesel quality. One of them is the iodine value, which is an important parameter that measures the total unsaturation within a mixture of fatty acids. Limitation of unsaturated fatty acids is necessary since warming of a higher quantity of these ones ends in either formation of deposits inside the motor or damage of lubricant. Determination of iodine value by official procedure tends to be very laborious, with high costs and toxicity of the reagents, this study uses an artificial neural network (ANN) in order to predict the iodine value property as an alternative to these problems. The methodology of development of networks used 13 esters of fatty acids in the input with convergence algorithms of backpropagation type were optimized in order to get an architecture of prediction of iodine value. This study allowed us to demonstrate the neural networks’ ability to learn the correlation between biodiesel quality properties, in this case iodine value, and the molecular structures that make it up. The model developed in the study reached a correlation coefficient (R) of 0.99 for both network validation and network simulation, with Levenberg-Maquardt algorithm.

Keywords: artificial neural networks, biodiesel, iodine value, prediction

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1026 Colony Size and Behaviors Characteristics of Monkeys in Peninsular Malaysia

Authors: Karimullah Karim, Shahrul Anuar, T. Dauda

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Swarm of research on monkey behavior exists, but were concerned with an aspect of molecular study in support of human primate and non-human primates. Many researchers take an interest in the study of Primates and their environment for the reason that they are intimately connected to humans in terms of human social behaviors. In this context, a study of the activity budget of monkeys was conducted in three states of Peninsular Malaysia. The chi-square test was served to analysis the behaviors and their variances in different study areas, effects of seasonal variation on behaviors, time differences in behaviors and habituated and non-habituated behaviors of monkeys. In consequent the behavior of moving (17%) was found higher followed by climbing (15%), eating (13%), and other social behaviors. All the behavior categories were found significant at p<0.05. The most common behavior of the monkeys in conclusion has been found associated with the restiveness of the animal and that their colony size is not rigid as it depends also on some other factors. This study can therefore serve as a starting point for the understanding of comparative behaviors of monkey in general and the study of the monkey behavior is thus recommended to be expanded to cover more study areas as well as species than in the present work.

Keywords: activity budget, Peninsular Malaysia, monkeys colony, behaviour

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1025 “Double Layer” Theory of Hydrogenation

Authors: Vaclav Heral

Abstract:

Ideas about the mechanism of heterogeneous catalytic hydrogenation are diverse. The Horiuti-Polanyi mechanism is most often referred to, based on the idea of a semi-hydrogenated state. In our opinion, it does not represent a satisfactory explanation of the hydrogenation mechanism, because, for example: (1) It neglects the fact that the bond of atomic hydrogen to the metal surface is strongly polarized, (2) It does not explain why a surface deprived of atomic hydrogen (by thermal desorption or by alkyne) loses isomerization capabilities, but hydrogenation capabilities remain preserved, (3) It was observed that during the hydrogenation of 1-alkenes, the reaction can be of the 0th order to hydrogen and to the alkene at the same time, which is excluded during the competitive adsorption of both reactants on the catalyst surface. We offer an alternative mechanism that satisfactorily explains many of the ambiguities: It is the idea of an independent course of olefin isomerization, catalyzed by acidic atomic hydrogen bonded on the surface of the catalyst, in addition to the hydrogenation itself, in which a two-layer complex appears on the surface of the catalyst: olefin bound to the surface and molecular hydrogen bound to it in the second layer. The rate-determining step of hydrogenation is the conversion of this complex into the final product. We believe that the Horiuti-Polanyi mechanism is flawed and we naturally think that our two-layer theory better describes the experimental findings.

Keywords: acidity of hydrogenation catalyst, Horiuti-Polanyi, hydrogenation, two-layer hydrogenation

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1024 Bounds on the Laplacian Vertex PI Energy

Authors: Ezgi Kaya, A. Dilek Maden

Abstract:

A topological index is a number related to graph which is invariant under graph isomorphism. In theoretical chemistry, molecular structure descriptors (also called topological indices) are used for modeling physicochemical, pharmacologic, toxicologic, biological and other properties of chemical compounds. Let G be a graph with n vertices and m edges. For a given edge uv, the quantity nu(e) denotes the number of vertices closer to u than v, the quantity nv(e) is defined analogously. The vertex PI index defined as the sum of the nu(e) and nv(e). Here the sum is taken over all edges of G. The energy of a graph is defined as the sum of the eigenvalues of adjacency matrix of G and the Laplacian energy of a graph is defined as the sum of the absolute value of difference of laplacian eigenvalues and average degree of G. In theoretical chemistry, the π-electron energy of a conjugated carbon molecule, computed using the Hückel theory, coincides with the energy. Hence results on graph energy assume special significance. The Laplacian matrix of a graph G weighted by the vertex PI weighting is the Laplacian vertex PI matrix and the Laplacian vertex PI eigenvalues of a connected graph G are the eigenvalues of its Laplacian vertex PI matrix. In this study, Laplacian vertex PI energy of a graph is defined of G. We also give some bounds for the Laplacian vertex PI energy of graphs in terms of vertex PI index, the sum of the squares of entries in the Laplacian vertex PI matrix and the absolute value of the determinant of the Laplacian vertex PI matrix.

Keywords: energy, Laplacian energy, laplacian vertex PI eigenvalues, Laplacian vertex PI energy, vertex PI index

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1023 Improvement in Quality-Factor Superconducting Co-Planer Waveguide Resonators by Passivation Air-Interfaces Using Self-Assembled Monolayers

Authors: Saleem Rao, Mohammed Al-Ghadeer, Archan Banerjee, Hossein Fariborzi

Abstract:

Materials imperfection, particularly two-level-system (TLS) defects in planer superconducting quantum circuits, contributes significantly to decoherence, ultimately limiting the performance of quantum computation and sensing. Oxides at air interfaces are among the host of TLS, and different material has been used to reduce TLS losses. Passivation with an inorganic layer is not an option to reduce these interface oxides; however, they can be etched away, but their regrowth remains a problem. Here, we report the chemisorption of molecular self-assembled monolayers (SAMs) at air interfaces of superconducting co-planer waveguide (CPW) resonators that suppress the regrowth of oxides and also modify the dielectric constant of the interface. With SAMs, we observed sustained order of magnitude improvement in quality factor -better than oxide etched interfaces. Quality factor measurements at millikelvin temperature and at single photon, XPS data, and TEM images of SAM passivated air interface sustenance our claim. Compatibility of SAM with micro-/nano-fabrication processes opens new ways to improve the coherence time in cQED.

Keywords: superconducting circuits, quality-factor, self-assembled monolayer, coherence

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1022 Clonal Evaluation of Malignant Mesothelioma

Authors: Sabahattin Comertpay, Sandra Pastorino, Rosanna Mezzapelle, Mika Tanji, Oriana Strianese, Andrea Napolitano, Tracey Weigel, Joseph Friedberg, Paul Sugarbaker, Thomas Krausz, Ena Wang, Amy Powers, Giovanni Gaudino, Harvey I. Pass, Fatmagul Ozcelik, Barbara L. Parsons, Haining Yang, Michele Carbone

Abstract:

Tumors are thought to be monoclonal in origin. This paradigm arose decades ago, primarily from the study of hematopoietic malignancies and sarcomas. The clonal origin of malignant mesothelioma (MM), a deadly cancer resistant to the current therapies, has not been investigated. Examination of the pleura from patients with MM shows often the presence of multiple pleural nodules, raising the question of whether they represent independent or metastatic growth processes. To investigate the clonality patterns of MM, we used the HUMARA (Human Androgen Receptor) assay to examine 14 sporadic and 2 familial Malignant Mesotheliomas (MM). Of 16 specimens studied, 15 were informative and 14/15 revealed two electrophoretically distinct methylated HUMARA alleles, indicating a polyclonal origin for these tumors. This discovery has important clinical implications, because an accurate assessment of tumor clonality is key to the design of novel molecular strategies for the treatment of MM.

Keywords: malignant mesothelioma, clonal origin, HUMARA, sarcomas

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1021 Development of a Robust Procedure for Generating Structural Models of Calcium Aluminosilicate Glass Surfaces

Authors: S. Perera, T. R. Walsh, M. Solvang

Abstract:

The structure-property relationships of calcium aluminosilicate (CAS) glass surfaces are of scientific and technological interest regarding dissolution phenomena. Molecular dynamics (MD) simulations can provide atomic-scale insights into the structure and properties of the CAS interfaces in vacuo as the first step to conducting computational dissolution studies on CAS surfaces. However, one limitation to date is that although the bulk properties of CAS glasses have been well studied by MD simulation, corresponding efforts on CAS surface properties are relatively few in number (both theoretical and experimental). Here, a systematic computational protocol to create CAS surfaces in vacuo is developed by evaluating the sensitivity of the resultant surface structure with respect to different factors. Factors such as the relative thickness of the surface layer, the relative thickness of the bulk region, the cooling rate, and the annealing schedule (time and temperature) are explored. Structural features such as ring size distribution, defect concentrations (five-coordinated aluminium (AlV), non-bridging oxygen (NBO), and tri-cluster oxygen (TBO)), and linkage distribution are identified as significant features in dissolution studies.

Keywords: MD simulation, CAS glasses, surface structure, structure-property, CAS interface

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1020 Molecular Identification of Pneumocystis SPP Isolated from Wild Rats in Tehran, Iran

Authors: Babak Rezavand

Abstract:

Pneumocystis carinii pneumonia (PCP) is one of the main causes of morbidity and mortality among immunocompromised and HIV-positive patients and remained one of the most important common opportunistic infections in these individuals in the world. Pneumocystis infection has been reported in many mammals. The aim of this study was to determine the Pneumocystis infection in wild rats as natural reservoirs of this organism in Tehran city, Iran. Fifty three rats (Rattus rattus) were live trapped in different areas of Tehran city, Iran. After isolation of their lung tissues and homogenization in sterile conditions, DNA was extracted. DNAs from all of the Pneumocystis species were amplified by pAZ102-H and pAZ102-E primers, and Nested PCR was performed using pAZ102-X and pAZ102-W primers from the initial PCR product for all the species of Pneumocystis. Amplification of the genome revealed the presence of Pneumocystis in the lungs of 17 rats (32%) through a PCR product with a bandwidth of 346 bp. In the Nested PCR amplification, from the PCR product of 53 rats, 64.2% of the samples were positive with a bandwidth of 261bp. Pneumocystis SPP infestation is highly prevalent among wild rats in Tehran city, indicating the existence of infection in the natural ecosystem of these rodents. As a host, rat plays an important role in the transmission of the microorganism in the world.

Keywords: pneumocystis SPP, rattus rattus, nested PCR, Tehran

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1019 Molecular Docking of Marrubiin in Candida Rugosa Lipase

Authors: Benarous Khedidja, Yousfi Mohamed

Abstract:

Infections caused by Candida species manifest in a number of diseases, including candidemia, vulvovaginal candidiasis, endocarditis, and peritonitis. These Candida species have been reported to have lipolytic activity by secretion of lipolytic enzymes such as esterases, lipases and phospholipases. These Extracellular hydrolytic enzymes seem to play an important role in Candida overgrowth. Candidiasis is commonly treated with antimycotics such as clotrimazole and nystatin, which bind to a major component of the fungal cell membrane (ergosterol). This binding forms pores in the membrane that lead to death of the fungus. Due to their secondary effects, scientists have thought of another treatment basing on lipase inhibition but we haven’t found any lipase inhibitors used as candidiasis treatment. In this work, we are interested to lipases inhibitors such as alkaloids as another candidiasis treatment. In the first part, we have proceeded to optimize the alkaloid structures and protein 3D structure using Hyperchem software. Secondly, we have docked inhibitors using Genetic algorithm with GOLD software. The results have shown ten possibilities of binding inhibitor to Candida rugosa lipase (CRL) but only one possibility has been accepted depending on the weakest binding energy.

Keywords: marrubiin, candida rugosa lipase, docking, gold

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1018 A Fundamental Study on the Molecular Chemistry of Agarwood Water Mixture

Authors: Fatmawati Adam, Saidatul Syaima Mat Tari, Saiful Nizam Tajuddin, Nurul Salwa Azliyana Hamzah

Abstract:

Essential oil of agarwood or known as Gaharu in Malay is highly prized for its value as luxury fragrances and incense. However, the complexities of the chemical composition of agarwood itself is the main challenge for establishment of an effective recovery method, which is able to ensure uniform qualities and standard for each batch of essential oil production. Agarwood markers are actually a blend of volatile and non-volatile compounds. While volatile molecules could be easily retrieved by the present distillation technique, the high solubility properties are the limiting factor for the latter. With regard to this, an elementary chemistry resolution study had been performed on commercial agarwood essential oil-water mixture, by the application of preparative HPLC and FTIR. Interpretation of the results leads to the theoretical postulation that, agarwood water mixture comprise of agarospirol, jinkohol, jinkoh eremol and khusenol. This study provides a pinpoint on the chemical characteristics of water soluble (non-volatile) agarwood compounds, therefore, will be an insight for researchers to develop a more strategic technique for their extraction. Thereafter the optimum quality of this essential oil could be controlled in a more improved way.

Keywords: Agarwood, Aquillaria Malaccensis, agarospirol, jinkohol, jinkoh eremol, khusenol

Procedia PDF Downloads 535