Hydrocarbon chain conformation in an intercalated surfactant monolayer and bilayer

Cetyl trimethyl ammonium (CTA) ions have been confined within galleries of layered CdPS3 at two different grafting densities. Low grafting densities are obtained on direct intercalation of CTA ions into CdPS3 to give Cd0.93PS3(CTA)0.14. Intercalation occurs with a lattice expansion of 4.8 Å with the interlamellar surfactant ion lying flat forming a monolayer. Intercalation at higher grafting densities was effected by a two-step ion-exchange process to give Cd0.83PS3(CTA)0.34, with a lattice expansion of 26.5 Å. At higher grafting densities the interlamellar surfactant ions adopt a tilted bilayer structure. 13C NMR and orientation-dependent IR vibrational spectroscopy on single crystals have been used to probe the conformation and orientation of the methylene 'tail' of the intercalated surfactant in the two phases. In the monolayer phase, the confined methylene chain adopts an essentially all-trans conformation with most of the trans chain aligned parallel to the gallery walls. On lowering the temperature, molecular plane aligns parallel, so that the methylene chain lies flat, rigid and aligned to the confining surface. In the bilayer phase, most bonds in the methylene chain are in trans conformation. It is possible to identify specific conformational sequences containing a gauche bond, in the interior and termini of the intercalated methylene. These high energy conformers disappear on cooling leaving all fifteen methylene units of the intercalated cetyl trimethyl ammonium ion in trans conformational registry at 40 K

Functionalization of the internal surfaces of layered cadmium thiophosphate with cationic surfactants: adsolubilization of uncharged organic molecules

Ion-exchange intercalation of the cationic surfactant cetyl trimethylammonium in layered CdPS3 leads to the formation of an intercalated bilayer within the galleries, thereby converting the internal surface of the layers from hydrophilic to hydrophobic. Several uncharged organic 'guest' molecules were found to be solubilized in the intercalated bilayer 'host'

Near-IR studies of recurrent nova V745 Scorpii during its 2014 outburst

The recurrent nova (RN) V745 Scorpii underwent its third known outburst on 2014 February 6. Infrared monitoring of the eruption on an almost daily basis, starting from 1.3d after discovery, shows the emergence of a powerful blast wave generated by the high velocity nova ejecta exceeding 4000 kms$^{-1}$ plowing into its surrounding environment. The temperature of the shocked gas is raised to a high value exceeding 10$^{8}$K immediately after outburst commencement. The energetics of the outburst clearly surpass those of similar symbiotic systems like RS Oph and V407 Cyg which have giant secondaries. The shock does not show a free-expansion stage but rather shows a decelerative Sedov-Taylor phase from the beginning. Such strong shockfronts are known to be sites for $\gamma$ ray generation. V745 Sco is the latest nova, apart from five other known novae, to show $\gamma$ ray emission. It may be an important testbed to resolve the crucial question whether all novae are generically $\gamma$ ray emitters by virtue of having a circumbinary reservoir of material that is shocked by the ejecta rather than $\gamma$ ray generation being restricted to only symbiotic systems with a shocked red giant (RG) wind. The lack of a free-expansion stage favors V745 Sco to have a density enhancement around the white dwarf (WD), above that contributed by a RG wind. Our analysis also suggests that the WD in V745 Sco is very massive and a potential progenitor for a future SN Ia explosion.Comment: To appear in ApJ (Letters

Evaluation of bacteriological diagnosis of smear positive pulmonary tubreculosis under programme conditions in three districts in the context of DOTS implementation in India

Objective: To study the smear and culture positivity rates in pulmonary tuberculosis patients declared as smear positive in the districts of North Arcot (Tamil Nadu), Raichur (Karnataka) and Wardha (Maharashtra) in India in order to evaluate the diagnosis of pulmonary tuberculosis at the field level under programme conditions. Methods: Two specimens of sputum from each of 320 patients in North Arcot, 314 patients in Raichur and 302 patients from Wardha district, all of whom had been reported as smear-positive at the field level, were examined by smear and culture. Findings: The proportion of specimens found to be smear-negative was 4.7% in North Arcot and 5.7% in Raichur as against 38.7% in Wardha. The proportions of culture negative specimens were 5.7% and 6.3% respectively in North Arcot and Raichur, while it was 35.6% at Wardha. The difference in the smear and culture negativity between Wardha and the other two districts was highly significant. Conclusions: The study revealed an unacceptably high level of false positives in sputum smear microscopy in the Wardha district. This could be attributed to the absence of systematic and intensive training in smear examination consequent to the non-implementation of the DOTS strategy in this district and a high standard of training offered in the RNTCP implemented districts

Survelliance of drug resistance in tuberculosis in the state of Tamil Nadu

Summary: Surveillance of drug resistance was carried out at State level to obtain data which are standardised and comparable using guidelines prescribed by the WHO/IUATLD Working Group on Anti-tuberculosis Drug Resistance Surveillance. Objective: To determine the proportion of initial and acquired drug resistance in cases of pulmonary tuberculosis in Tamilnadu, in order to use the level of drug resistance as a performance indicator of the National Tuberculosis Programme. Methods: Two specimens of sputum from each of a total of 713 patients attending 145 participating centres all over the state were tested by smear and culture examination and drug susceptibility tests of Isoniazid, Rifampicin, Ethambutol and Streptomycin. Results: Out of 400 patients for whom drug susceptibility results were available, 384 (96%) had no history of previous anti-tuberculosis treatment. Of these, 312 (81%) were susceptible to all the drugs tested. Resistance to isoniazid was seen in 15.4% of patients and to Rifampicin in 4.4% including resistance to Isoniazid and Rifampicin in 3.4%. Conclusion: There has been a gradual increase in initial drug resistance over the years in this part of the country

The peculiar extinction law of SN2014J measured with The Hubble Space Telescope

The wavelength-dependence of the extinction of Type Ia SN2014J in the nearby galaxy M82 has been measured using UV to near-IR photometry obtained with the Hubble Space Telescope, the Nordic Optical Telescope, and the Mount Abu Infrared Telescope. This is the first time that the reddening of a SN Ia is characterized over the full wavelength range of $0.2$-$2$ microns. A total-to-selective extinction, $R_V\geq3.1$, is ruled out with high significance. The best fit at maximum using a Galactic type extinction law yields $R_V = 1.4\pm0.1$. The observed reddening of SN2014J is also compatible with a power-law extinction, $A_{\lambda}/A_V = \left( {\lambda}/ {\lambda_V} \right)^{p}$ as expected from multiple scattering of light, with $p=-2.1\pm0.1$. After correction for differences in reddening, SN2014J appears to be very similar to SN2011fe over the 14 broad-band filter light curves used in our study.Comment: Accepted for publication in ApJ

Isolation of tubercle bacilli from sputum samples of patients in the field studies by the cetylpyridinium chloride-sodium chloride & sodium hydroxide methods

A total of 125 sputum specimens, collected in the field, were homogenised, aliquoted in sterile universal containers and randomly allocated to the cetylpyridinium chloride - sodium chloride (CPCNaCl) method and sodium hydroxide ( NaOH) method for culture of tubercle bacilli. After storage for 8 days at ambient temperature in the field laboratory at Thiruvallur, the aliquots were transported to the main laboratory at Madras where they were processed for culture by the respective methods. The yield of positive cultures in the CPC-NaCl (31/125) method was only marginally better than that in the NaOH method (27/125) (95% Cl being-3.4 to 9.8%), while the contamination of cultures was significantly less in the CPC-NaCl method ( 3/125) than in the NaOH method (12/125) (95% Cl being 2.2 to 12.2%). As the CPC-NaCl method has advantages over the NaOH method in reducing contamination, in augmenting the yield of positive cultures and also in its simplicity, it can be applied in field studies

Optimization and Analysis of Wireless Networks Lifetime using Soft Computing for Industrial Applications

Recently, wireless networks are applied in various engineering and industrial applications. One of the critical problems in wireless network system optimization in intelligent applications is obtaining an adequate energy fairness level. This issue can be resolved by applying effective cluster-based routing optimization with multi-hop routing. Hence a new network structure is developed that is derived from energy consumption architecture by applying soft computing strategies such as evolutionary operators in determining the exact clusters for optimizing energy consumption. The new effective evolutionary operators are tested in the optimization of a lifetime. The proposed method is simulated for different values of the routing factor, α, for different types of networks. The energy levels range from 0.4 to 0.8, achieving good results for nearly 2500 rounds. The proposed strategy optimizes the clusters, and its head is selected reliably. The optimization of cluster head choice has been done based on the base station distance, the energy of the node, and the node's energy efficiency. The reliability of the long-distance nodes is increased during the data transmission by modifying the size of the area of the candidate set of nodes in contrast the near-distance node's energy consumption is reduced. For the energy levels that range from 0.4 to 0.8, the higher network throughput is obtained at the same time network lifetime is optimized compared to other well-known approaches. The proposed model is expected for different industrial wireless network applications to optimize the systems during the long-run simulation and to achieve high reliability and sustainability

Algorithm for the comparison of human periodic movements using wearable devices

In the context of teaching-learning of motor skills in a virtual environment, videos are generally used. The person who wants to learn a certain movement watches a video and tries to perform the activity. In this sense, feedback is rarely thought of. This article proposes an algorithm in which two periodic movements are compared, the one carried out by an expert and the one carried out by the person who is learning, in order to determine how closely these two movements are performed and to provide feedback from them. The algorithm starts from the capture of data through a wearable device that yields data from an accelerometer; in this case, the data of the expert and the data of the person who is learning are captured in a dataset of salsa dance steps. Adjustments are made to the data in terms of Pearson iterations, synchronization, filtering, and normalization, and DTW, linear regression, and error analysis are used to make the corresponding comparison of the two datasets. With the above, it is possible to determine if the cycles of the two signals coincide and how closely the learner’s movements resemble those of the expert

A note on the occurrence of large scale fish mortality along the Chaliyar River near Beypore

An unusual phenomenon of large scale fish mortality was noticed at Chaliyar river in Beypore on the morning of 3rd May 1966. The fishermen noticed hundreds of fish struggling and coming up on the surface of water in a dazed and dead condition and showing signs of suffocation. They caught the dead and dying fish and sold them immediately in the market. No adverse effect as a result of eating these fish was noticed