Corrosion inhibition of mild steel in 1 M HCl using water soluble chitosan derivative of vanillin.

The water-soluble chitosan derivative (WSCD) was made by mixing chitosan with sodium hydroxide, treating the mixture with chloroacetic acid, and then forming a Schiff base with vanillin in an acidic medium. In this study, we examined the corrosion-inhibiting ability of a WSCD on mild steel surfaces in acidic environments. Weight loss, EIS, PDP, LPS, and OCP measurements were used to study the corrosion resistance on mild steel surfaces in 1 M HCl solutions with known concentrations of WSCD. The results show that WSCD functions effectively as a mixed-type anodic and cathodic inhibitor, providing 87 % corrosion inhibition efficiency at 75 ppm. Using SEM to investigate the morphology of corroded mild steel with and without varying amounts of WSCD, impedance measurements show the development of a thin film of inhibitor on the metal surface, the extent of which increases as the inhibitor concentration rises. The WSCD molecule first adsorbs on mild steel and follows Langmuir adsorption isotherm. It is found that the (∆Gads0)adsorption's free energy is -17.473 kJ/mol. The contact angle measurements confirm that the hydrophobicity of the metal surface has increased as a result of the inhibitor's thin film development.

Evaluation of ELISA and PCR in parallel to single intradermal cervical tuberculin test (SICT) for diagnosis of tuberculosis in buffaloes.

Bovine tuberculosis is an economically important disease with very high zoonotic potential. Single intradermal cervical tuberculin test (SICT) is considered a gold standard assay for the diagnosis of bovine tuberculosis. However, bovines especially buffaloes may produce a false negative result when the animal becomes cell-mediated immune (CMI) anergic in the advanced stage of the disease. In the present study, ELISA and PCR assays were successfully demonstrated to be useful in diagnosing tuberculosis especially in the CMI anergic buffaloes infected with Mycobacterium bovis. ELISA and PCR assays are able to detect 8.94% and 8.13%, respectively, more animals as positive in comparison to standard SICT assay in a selected population of 123 buffaloes. The moderate agreement between SICT and ELISA (k: 0.528; 0.249-0.807), a substantial agreement between SICT and PCR (k: 0.648; 0.364-0.931), and high agreement between ELISA and PCR (k: 0.856; 0.697-1.0) highlight that ELISA and PCR, if used in parallel with SICT, will provide better sensitivity over single assay. Reduction of false negative reactors may help in minimizing the zoonotic threat from bovine tuberculosis especially in disease endemic region where human and livestock interface is quite high.

Corrosion inhibition of mild steel using poly (2-ethyl -2-oxazoline) in 0.1M HCl solution.

Effective inhibition of metallic corrosion to prevent its consequent loss is one of the serious apprehensions for industries in the modern world. This paper analyses the application of poly(2-ethyl-2-oxazoline) (PEOX) as an effective inhibitor of corrosion, when it is made to be in contact with the surfaces of mild steel (MS). The sustainability of MS against corrosion in 0.1 M Hydrochloric acid solution in the presence of known concentration of PEOX is assessed by potentiodynamic polarization (PDP) measurements, linear polarization studies (LPR), and electrochemical impedance spectroscopy (EIS). It was observed that PEOX behaves as better inhibitor for mild steel corrosion in 0.1 M HCl solution and it show enhanced inhibition efficiency (IE%) 79% at a concentration of 50 ppm. The polarization experiments indicated that addition of PEOX in concentrations varies from 25 ppm to 50 ppm induces a decrease of both cathodic and anodic currents densities. Also, the micrographs recorded by the Scanning Electron Microscopy confirm that molecules of PEOX act as corrosion inhibitors for the surfaces of MS in 0.1 M HCl. The stability of the MS surface in a corrosion-prone environment is traced by measuring the contact angles of water droplets placed on the MS surface, to quantify the extent of deterioration, if any, due to corrosion. The results presented here show that the compound PEOX performs as a mixed-type inhibitor against corrosion at the MS surface in acidic medium. Theoretical studies based on the electronic structure of PEOX in aqueous medium also support its performance as a successful corrosion-inhibitor.

The comparison of effects of fentanyl and dexmedetomidine as adjuvants to ropivacaine for ultrasound-guided transversus abdominis plane block for postoperative pain in cesarean section under spinal anesthesia -A randomized controlled trial.

BACKGROUND AND AIMS: Transversus abdominis plane (TAP) block has been effectively used for anterior abdominal wall analgesia. The aim of the study was to compare the duration of analgesia produced by two drugs fentanyl and dexmedetomidine as adjuvants to ropivacaine in TAP block under ultrasound-guidance after lower segment cesarean section in a randomized controlled trial. MATERIAL AND METHODS: Sixty-four women of American Society of Anaesthesiologists (ASA) physical status II coming for cesarean sections were randomized to receive TAP blocks on each side of the abdomen using the local anesthetic drug 20 ml of 0.5% ropivacaine with either fentanyl 25 mcg or dexmedetomidine 25 mcg. A ten point numerical pain score was done at baseline, at 1 h and then at intervals of 4 h postoperatively. The hemodynamic parameters such as heart rate, blood pressure, and pulse oximetry were also monitored as above. The time to first analgesia demand from the time of the block and the total analgesic consumption were recorded. The statistical analysis was done by Mann-Whitney U test and the analgesics consumption by using Chi-square test with R software. RESULTS: Our primary end-point was to assess the duration of analgesia produced by fentanyl added to ropivacaine for ultrasound-guided TAP block, which were 125 min with Q1-Q3 as 110-180 and dexmedetomidine 130 min with Q1-Q3 as 105-161 (P value = 0.47). The amount of analgesics used in the postoperative period in both the groups were analyzed using the Chi-square test not found to have any significant difference between both the groups (P-value = 0.512). CONCLUSION: Fentanyl and dexmedetomidine as adjuvants to ropivacaine in ultrasound-guided TAP block were equally effective in both prolongation of analgesia and reducing the total consumption of analgesics.

Random amplified polymorphic DNA-based molecular heterogeneity analysis of Salmonella enterica isolates from foods of animal origin.

AIM: This study aims to study the significance of random amplified polymorphic DNA (RAPD) typing in heterogeneity analysis of Salmonella serovars, isolated from foods of animal origin. MATERIALS AND METHODS: Salmonella serovars isolated and identified from different foods of animal origin such as meat, milk, and egg by standard bacteriological methods. DNA isolated from all 10 isolates which are confirmed by biochemical and serotyping methods and then RAPD was performed using the primers OPB 10, primer 1290, NSC I, NSC II, and primer 3. Then, RAPD data were analyzed using the BioNumerics software, Belgium, Germany. RESULTS: RAPD polymerase chain reaction (PCR) using five primers, namely OPB 10, primer 1290, NSC I, NSC II, and primer 3, classified the 10 isolates into 9, 10, 10, 7, and 10 RAPD-PCR types with discriminating powers of 0.1987, 0.423, 0.50889, 0.1842, and 0.2582, respectively. The phylogram constructed with NSC I profile classified isolates based on geographical origin. Primer 1290, NSC II, and primer 3 produced some uniform bands in all isolates indicating their binding ability in conserved genomic region. This study revealed that RAPD profile can be best used for finding out the heterogeneity at molecular level of Salmonella isolates in combination with other molecular and phenotypic typing techniques. Thus, our results support earlier observation of its significance by different workers on different Salmonella serotypes. CONCLUSION: Repeatability of RAPD-PCR is insufficient to distinguish genetic differences among Salmonella serovars.