28 research outputs found

    Corrosion Inhibition of Mild-Steel in (1M) HCl using Spands Reagent

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    The effect of Spands Reagent on the dissolution of Mild-steel in 1M HCl solution was studied using weight loss and galvanostatic polarization techniques. The inhibition efficiency of inhibitor increases with concentration to attain (75.26%) at concentration  1—10-2 M ,and standing time for 180 min at 25°C. Temperature effect on the corrosion behavior was studied at temperature range from 25-45°C, the results showed that inhibition efficiency decreased with increasing temperature to attain (64.53%) at concentration 1—10-2 M at 45°C and with standing time equal to 180 min. The effect of temperature on the rate of corrosion in the absence and presence of Spands Reagent was also studied. The Kinetic Parameters were calculated and discussed. The polarization curves revealed that the studied inhibitor represent a mixed type inhibitors. Adsorption of inhibitor was isotherm physisorption type

    Synthesis, Analytical and Theoretical Studies of (Z)-4-amino-3-hydroxy-2-((4-(N-(5-methylisoxazol-3-yl)Sulfamoyl)Phenyl)Diazenyl)Naphthalene-1-Sulfonic Acid

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    New azodye that characterize (Z)-4-amino-3-hydroxy-2-((4-(N-(5-methylisoxazol-3-yl) sulfamoyl) phenyl)diazenyl)naphthalene-1-sulfonic acid (1) was synthesized. The azodye has been characterized by IR, visible spectra and elemental (CHN) analysis. The results of visible spectra which recorded in the range (360-6540) nm were showed that the maximum wave length (λmax) of azodye was 500 nm. Analytical studies carried on the dye, the results of the solvent effect were showed high solubility in ethanol and water. But, the results of the pH effect in a range of buffer solution were gave three isopestic points. The ionization constant (pKa) and protonation constant (pKb) were calculated by using the half height method. The results were showed that the pKp1 and pKp2 of each nitrogen atom and pKa of OH-group were equal to 2.5, 4.5 and 8.5 respectively. Theoretical studies also carried on azodye (1). The actual and optimal bonds length of -N=N- was equal to 1.248 in each. Though, internal coordinate mechanics (ICM) of (1) was showed that the angle type in most of atoms was dihedral. But, the R and S configuration were observed in other atoms in the structure of azodye. The results also indicated that the torsion angles (ψ) of (1) were variable. High close contacts of atoms were observed in the structure of azodye. The molecular mechanics (MM2) properties was intended for (1), the results showed that the stretch, bend, stretch-bend, torsion, non-1,4 VDW, 1,4 VDW and the total energy were equal to 61.0809, 627.0240, -1.6517, 179.0634, 4686.8146, 33.0379 and 5585.3692 kcal/mol respectively. High VDW interactions of this molecule was observed, due to the results of dipole/dipole were not computed. Thus, the result of MM2 minimization for azodye (1) was showed high VDW interactions of this molecule higher than before the minimization, due to the result of dipole/dipole was also not computed. The high steric energy (1235.782) was affecting the results of minimization. However, the results of the molecular mechanics force field (MMFF94) energy and gradient for azodye (1) were showed that the total energy and RMS gradient were equal to 26223.422 kcal/ mol and 9113.745 respectively. Further, the results of MMFF94 minimization and MMFF94 minimization/sampling of azodye (1) were showed that the minimization was attended successfully using this method. Keywords: Internal coordinate, Molecular mechanics, Azodye

    Editorial: EBV-Associated Carcinomas: Presence, Role, and Prevention Strategies.

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    This special issue addresses an important topic related to the role of Epstein-Barr virus (EBV) in human carcinomas initiation and progression, which is one of the most common viral infections worldwide. Today, the relationship between EBV infection and several types of human lymphomas is clearly established, including Hodgkin and Burkitt's lymphoma; meanwhile, it was recently pointed out that EBV is present in nasopharyngeal carcinomas as well as other epithelial cancers (1). EBV is ubiquitous human herpesvirus 4, its genome codes more than 85 proteins of which only few are well-understood; More specifically, six nuclear antigens (EBNA: 1, 2, 3A, 3B, 3C, and LP); three latent membrane proteins/genes (LMP: 1, 2A, 2B) as well as small non-polyadenylated RNAs, EBERs 1 and 2 in addition to few microRNAs have been identified so far, as key regulators, of the oncogenic activity of this virus (2, 3). Present estimates indicate that EBV causes 200,000 new cancer cases annually, accounting for ~2% of cancers worldwide (Cancer Research UK). On the other hand, it is important to emphasize that recent investigations have revealed the possible involvement of EBV in other cancers such as cervical, gliomas, and breast, which are highlighted in this issue.This work is supported by Qatar University grants# GCC-2017-002 QU/KU and QUCG-CMED-20182019-3

    Synthesis and Biological Activity of Three Novel Azo Dyes

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    The azo dyes that named, (E)-4-((2-nitrophenyl) diazenyl) benzene-1,3-diol (1), (E)-4- ((3-nitrophenyl) diazenyl) benzene-1,3-diol (2) and (E)-4-((4-nitrophenyl) diazenyl) benzene-1,3-diol (3) were synthesized and then characterized using IR, UV-visible spectrum. These results were compared with that obtained by ChemBio 3D Ultra - [Chem3D XML] Gaussian Interface and were seems to be identical. Then, the antimicrobial activity of each azo dye was carried out against two bacterial strains: Staphylococcus aureus NCTC 6571, and Escherichia coli ATCC 25922, and fungal strains of Candida albicans using Agar-well diffusion method. The results were showed that the three azo dyes were biologically active and the best reactivity was observed in (2). Though, the biological activity of (1) with NO2 group in ortho- position remained reasonable against Candida albicans. But, the effect of (1) was resisted by Staphylococcus aureus and Escherichia coli. However, the (2) and (3) with substituted NO2 group in meta- and para- positions respectively were showed better reactivity’s than (1) towered Candida albicans and Staphylococcus aureus. Further, the Gaussian interface properties and the conformational analysis of (1), (2) and (3) were intended. The results were indicated that the variations in the properties of each azo dye and their conformational energies of generated conformers can affect their biological activity afterward. Keywords: key words, Azo dyes, Staphylococcus aureus, Escherichia coli, Candida albicans, Agar-well diffusion method, Antimicrobial activit

    The Effect of a DNA Repair Gene on Cellular Invasiveness: Xrcc3 Over-Expression in Breast Cancer Cells

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    Over-expression of DNA repair genes has been associated with resistance to radiation and DNA-damage induced by chemotherapeutic agents such as cisplatin. More recently, based on the analysis of genome expression profiling, it was proposed that over-expression of DNA repair genes enhances the invasive behaviour of tumour cells. In this study we present experimental evidence utilizing functional assays to test this hypothesis. We assessed the effect of the DNA repair proteins known as X-ray complementing protein 3 (XRCC3) and RAD51, to the invasive behavior of the MCF-7 luminal epithelial-like and BT20 basal-like triple negative human breast cancer cell lines. We report that stable or transient over-expression of XRCC3 but not RAD51 increased invasiveness in both cell lines in vitro. Moreover, XRCC3 over-expressing MCF-7 cells also showed a higher tumorigenesis in vivo and this phenotype was associated with increased activity of the metalloproteinase MMP-9 and the expression of known modulators of cell-cell adhesion and metastasis such as CD44, ID-1, DDR1 and TFF1. Our results suggest that in addition to its' role in facilitating repair of DNA damage, XRCC3 affects invasiveness of breast cancer cell lines and the expression of genes associated with cell adhesion and invasion

    Illegal births and legal abortions – the case of China

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    BACKGROUND: China has a national policy regulating the number of children that a woman is allowed to have. The central concept at the individual level application is "illegal pregnancy". The purpose of this article is to describe and problematicize the concept of illegal pregnancy and its use in practice. METHODS: Original texts and previous published and unpublished reports and statistics were used. RESULTS: By 1979 the Chinese population policy was clearly a policy of controlling population growth. For a pregnancy to be legal, it has to be defined as such according to the family-level eligibility rules, and in some places it has to be within the local quota. Enforcement of the policy has been pursued via the State Family Planning (FP) Commission and the Communist Party (CP), both of which have a functioning vertical structure down to the lowest administrative units. There are various incentives and disincentives for families to follow the policy. An extensive system has been created to keep the contraceptive use and pregnancy status of all married women at reproductive age under constant surveillance. In the early 1990s FP and CP officials were made personally responsible for meeting population targets. Since 1979, abortion has been available on request, and the ratio of legal abortions to birth increased in the 1980s and declined in the 1990s. Similar to what happens in other Asian countries with low fertility rates and higher esteem for boys, both national- and local-level data show that an unnaturally greater number of boys than girls are registered as having been born. CONCLUSION: Defining a pregnancy as "illegal" and carrying out the surveillance of individual women are phenomena unique in China, but this does not apply to other features of the policy. The moral judgment concerning the policy depends on the basic question of whether reproduction should be considered as an individual or social decision

    AI is a viable alternative to high throughput screening: a 318-target study

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    : High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery
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