We report here the occurrence of a commensurate phase in a rapidly solidified Ti-Fe alloy. On the basis of energy-dispersive x-ray analysis, the composition of the alloy has been analyzed and found to correspond to Ti~Fei -, Si, (x=0.03-0.06), within the limits of experimental error. The x-rayand electron-diffraction studies have revealed commensurate ordering based on a metastable CsCl-type phase with lattice parameter close to 0.298 nm. Available diffraction evidence suggests that commensuration in this alloy takes place along &IOO) directions of the basic cell. The ordered cell corresponds to a tetragonal one with cell parameters a=0.298 nm and c=9x0.298 nm. All the three variants arising due to symmetry breaking of the basic cell have been observed to be related by a threefold symmetry operation. Coherent diffraction of these yields cubic symmetry.

18Salmonella enterica serovar Typhimurium (S. Typhimurium), a non-typhoidal Salmonella 19 (NTS), result in a range of diseases, including self-limiting gastroenteritis, bacteremia, enteric 20 fever, and focal infections representing a major disease burden worldwide. There is still a 21 significant portion of Salmonella genes whose functional basis to overcome host innate defense 22 mechanisms, consequently causing disease in host, largely remains unknown. Here, we have 23 applied a high-throughput transposon sequencing (Tn-seq) method to unveil the genetic factors 24 required for the growth or survival of S. Typhimurium under various host stressors simulated in 25 vitro. A highly saturating Tn5 library of S. Typhimurium 14028s was subjected to selection 26 during growth in the presence of short chain fatty acid (100 mM propionate), osmotic stress (3% 27 NaCl) or oxidative stress (1 mM H2O2) or survival in extreme acidic pH (30 min in pH3) or 28 starvation (12 days in 1X PBS). We have identified an overlapping set of 339 conditionally 29 essential genes (CEGs) required by S. Typhimurium to overcome these host insults. 30Interestingly, entire eight genes encoding F0F1-ATP synthase subunit proteins were required for 31 fitness in all five stresses. Intriguingly, total 88 genes in Salmonella pathogenicity island (SPI), 32 including SPI-1, SPI-2, SPI-3, SPI-5, SPI-6 and SPI-11 are also required for fitness under the in 33 vitro conditions evaluated in this study. Additionally, by comparative analysis of the genes 34 identified in this study and the genes previously shown to be required for in vivo fitness, we 35 identified novel genes (marBCT, envF, barA, hscA, rfaQ, rfbI and putative proteins 36 STM14_1138, STM14_3334, STM14_4825, and STM_5184) that has compelling potential to be 37 exploited as vaccine development and/or drug target to curb the Salmonella infection. 38