EFFECTS OF TIN ON HARDNESS, WEAR RATE AND COEFFICIENT OF FRICTION OF CAST CU-NI-SN ALLOYS

An investigation was carried out to understand the effects of Sn on hardness, wear rate and the coefficient of friction of spinodal Cu-Ni-Sn alloys. Alloys of appropriate compositions were melted in a crucible furnace under argon atmosphere and cast into sand moulds. Solution heat treated and aged specimens were tested for hardness, wear rate and the coefficient of friction. It was found that the hardness increases when the Sn content increases from 4% to 8% in the solution heat treated conditions. The peak aging time is found to decrease with an increase in the Sn content. Further, the coefficient of friction is independent of hardness whereas the wear rate decreases linearly with hardness irrespective of Sn content

Contribution of Cystine-Glutamate Antiporters to the Psychotomimetic Effects of Phencyclidine

Altered glutamate signaling contributes to a myriad of neural disorders, including schizophrenia. While synaptic levels are intensely studied, nonvesicular release mechanisms, including cystine–glutamate exchange, maintain high steady-state glutamate levels in the extrasynaptic space. The existence of extrasynaptic receptors, including metabotropic group II glutamate receptors (mGluR), pose nonvesicular release mechanisms as unrecognized targets capable of contributing to pathological glutamate signaling. We tested the hypothesis that activation of cystine–glutamate antiporters using the cysteine prodrug N-acetylcysteine would blunt psychotomimetic effects in the rodent phencyclidine (PCP) model of schizophrenia. First, we demonstrate that PCP elevates extracellular glutamate in the prefrontal cortex, an effect that is blocked by N-acetylcysteine pretreatment. To determine the relevance of the above finding, we assessed social interaction and found that N-acetylcysteine reverses social withdrawal produced by repeated PCP. In a separate paradigm, acute PCP resulted in working memory deficits assessed using a discrete trial t-maze task, and this effect was also reversed by N-acetylcysteine pretreatment. The capacity of N-acetylcysteine to restore working memory was blocked by infusion of the cystine–glutamate antiporter inhibitor (S)-4-carboxyphenylglycine into the prefrontal cortex or systemic administration of the group II mGluR antagonist LY341495 indicating that the effects of N-acetylcysteine requires cystine–glutamate exchange and group II mGluR activation. Finally, protein levels from postmortem tissue obtained from schizophrenic patients revealed significant changes in the level of xCT, the active subunit for cystine–glutamate exchange, in the dorsolateral prefrontal cortex. These data advance cystine–glutamate antiporters as novel targets capable of reversing the psychotomimetic effects of PCP

Diagnostic accuracy of magnetic resonance enterography and small bowel ultrasound for the extent and activity of newly diagnosed and relapsed Crohn's disease (METRIC): a multicentre trial

Magnetic resonance enterography (MRE) and ultrasound are used to image Crohn's disease, but their comparative accuracy for assessing disease extent and activity is not known with certainty. Therefore, we did a multicentre trial to address this issue. We recruited patients from eight UK hospitals. Eligible patients were 16 years or older, with newly diagnosed Crohn's disease or with established disease and suspected relapse. Consecutive patients had MRE and ultrasound in addition to standard investigations. Discrepancy between MRE and ultrasound for the presence of small bowel disease triggered an additional investigation, if not already available. The primary outcome was difference in per-patient sensitivity for small bowel disease extent (correct identification and segmental localisation) against a construct reference standard (panel diagnosis). This trial is registered with the International Standard Randomised Controlled Trial, number ISRCTN03982913, and has been completed. 284 patients completed the trial (133 in the newly diagnosed group, 151 in the relapse group). Based on the reference standard, 233 (82%) patients had small bowel Crohn's disease. The sensitivity of MRE for small bowel disease extent (80% [95% CI 72-86]) and presence (97% [91-99]) were significantly greater than that of ultrasound (70% [62-78] for disease extent, 92% [84-96] for disease presence); a 10% (95% CI 1-18; p=0·027) difference for extent, and 5% (1-9; p=0·025) difference for presence. The specificity of MRE for small bowel disease extent (95% [85-98]) was significantly greater than that of ultrasound (81% [64-91]); a difference of 14% (1-27; p=0·039). The specificity for small bowel disease presence was 96% (95% CI 86-99) with MRE and 84% (65-94) with ultrasound (difference 12% [0-25]; p=0·054). There were no serious adverse events. Both MRE and ultrasound have high sensitivity for detecting small bowel disease presence and both are valid first-line investigations, and viable alternatives to ileocolonoscopy. However, in a national health service setting, MRE is generally the preferred radiological investigation when available because its sensitivity and specificity exceed ultrasound significantly. National Institute of Health and Research Health Technology Assessment. [Abstract copyright: Copyright © 2018 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.

24,4,8-Trioxa-21-aza-1,3,6(1,2)-tri­benzena-2(2,3)-bicyclo­[3.3.0]octa­na­cyclo­octa­phane

The crystal structure of the title compound, C26H25NO3, was determined as part of an investigation of host–guest and electron donor–acceptor complexes. The oxazole and the pyrrole rings both adopt envelope conformations. The dihedral angle between the two benzene rings directly linked to the oxazole ring is 49.5 (1)°. The crystal structure is stabilized by a C—H⋯π inter­action

Unravelling the genome-wide contributions of specific 2-alkyl-4-quinolones and PqsE to quorum sensing in Pseudomonas aeruginosa

The pqs quorum sensing (QS) system is crucial for Pseudomonas aeruginosa virulence both in vitro and in animal models of infection and is considered an ideal target for the development of anti-virulence agents. However, the precise role played by each individual component of this complex QS circuit in the control of virulence remains to be elucidated. Key components of the pqs QS system are 2-heptyl-4-hydroxyquinoline (HHQ), 2-heptyl-3-hydroxy-4-quinolone (PQS), 2-heptyl-4-hydroxyquinoline N-oxide (HQNO), the transcriptional regulator PqsR and the PQS-effector element PqsE. To define the individual contribution of each of these components to QS-mediated regulation, transcriptomic analyses were performed and validated on engineered P. aeruginosa strains in which the biosynthesis of 2-alkyl 4-quinolones (AQs) and expression of pqsE and pqsR have been uncoupled, facilitating the identification of the genes controlled by individual pqs system components. The results obtained demonstrate that i) the PQS biosynthetic precursor HHQ triggers a PqsR-dependent positive feedback loop that leads to the increased expression of only the pqsABCDE operon, ii) PqsE is involved in the regulation of diverse genes coding for key virulence determinants and biofilm development, iii) PQS promotes AQ biosynthesis, the expression of genes involved in the iron-starvation response and virulence factor production via PqsR-dependent and PqsR-independent pathways, and iv) HQNO does not influence transcription and hence does not function as a QS signal molecule. Overall this work has facilitated identification of the specific regulons controlled by individual pqs system components and uncovered the ability of PQS to contribute to gene regulation independent of both its ability to activate PqsR and to induce the iron-starvation response

2,5-Dimethyl-1-phenyl­sulfonyl-1H-pyrrole-3,4-dicarbaldehyde

In the title compound, C14H13NO4S, the mean planes of the pyrrole and phenyl rings form a dihedral angle of 88.7 (1)°. The aldehyde groups are slightly twisted from the pyrrole plane. In the crystal structure, mol­ecules are linked into a three-dimensional framework by C—H⋯O hydrogen bonds

Experimental investigation on the engine performance and emission behaviour of turpentine - diesel dual fuel operated modified DI diesel engine / R. Karthikeyan … [et al.]

The dual fuel technique offers the advantage of easy conversion of the diesel engine to work on the dual fuel mode with little engine modifications. In this mode, the primary fuel (turpentine) is inducted along with inlet air stream and the pilot fuel (diesel) is injected through the regular injection system. The primary fuel (turpentine) shared the maximum energy in the power production but the pilot fuel shared only a least part and act as an ignition source. The engine with this facility has been operated under various load conditions and at various turpentine energy shares. The energy share that provides better performance has been identified and compared with diesel fuel operation. From the obtained results it was proved that this engine offered higher BTE at full load and smoke free operation at all loads. The CO and HC emissions were higher and operated with very low NOx emission at all loads. The results also proved that the dual fuel operation successfully replaced 75% of diesel usage with turpentine fuel

CFD parametric study of thermal performance of different fruit packaging box designs

Air temperature and relative humidity values of cold storage conditions are the major factor affecting the perishability of fresh fruits. The sooner the field heat is extracted from the products and the proper temperature is maintained consistency throughout the cold chain, larger it will be shelf life of these products. Forced air cooling is the most commonly used technique to remove the field heat in post-harvest storage. Energy-efficient and quality-oriented cold storage mainly depends on the time to remove the heat. This time can be reduced by optimizing the configuration of the vent holes of the packaging box, namely it dimension (area), it shape, alignment and position. This paper shows the numerical predictions of air temperature and velocity by a CFD parametric study of eight different vent hole configurations. These configurations consider a packaging box with double wall. The vent holes of each wall have different dimension and shape. The vent holes of both walls can be also aligned or unaligned. The analysis of results aims to determine the best configurations that improve the cooling rate, the airflow and temperature uniformity. The numerical predictions of the air temperature show close values, but three configurations can be identified as predicting the lowest air temperature values with lowest standard deviation. These results may help on the development of new configuration for fruit boxes that promote the extension of the fruits shelflife.(undefined

Discrepancies in assessing anterior chamber activity among uveitis specialists

PURPOSE: To evaluate current practices in anterior chamber (AC) inflammation assessment among uveitis specialists. METHODS: Uveitis specialists were invited to participate in an electronic survey designed to understand their practice in assessing AC inflammation. RESULTS: Sixty-five ophthalmologists participated in the survey. Of them, 69.2 % (n = 45) reported using the current Standardization of Uveitis Nomenclature (SUN) guidelines of a 1 × 1-mm slit beam when grading AC cells. Only 38.5 % (n = 5) reported routinely counting the number of cells. In the management of uveitis, 98.5 % (n = 64) valued flare assessment, but 84.6 % (n = 55) did not use laser flare photometry. In total, 36.9 % (n = 24) agreed that laser flare photometry would change their management, while 16.9 % (n = 11) did not see its usefulness. The remaining participants were undecided. CONCLUSION: A number of issues limit the clinical assessment of AC inflammation. Different classifications are still being used despite efforts to standardize practice. While the value of flare is widely recognized, the role of laser flare photometry remains controversial