Integration of optical and acoustic sensors for D underwater scene reconstruction.

Combination of optical and acoustic sensors to overcome the shortcomings presented by optical systems in underwater 3D acquisition is an emerging field of research. In this work, an opti-acoustic system composed by a single camera and a multibeam sonar is proposed, providing a simulation environment to validate its potential use in 3D reconstruction. Since extrinsic calibration is a prerequisite for this kind of feature-level sensor fusion, an effective approach to address the calibration problem between a multibeam and a camera system is presented.Peer Reviewe

The origin of the Fe K features in Markarian 205 and Markarian 509

We examine the 3-10 keV EPIC spectra of Mrk 205 and Mrk 509 to investigate their Fe K features. The most significant feature in the spectra of both objects is an emission line at 6.4 keV. The spectra can be adequately modelled with a power law and a relatively narrow (sigma < 0.2 keV) Fe K alpha emission line. Better fits are obtained when an additional Gaussian emission line, relativistic accretion-disk line, or Compton reflection from cold material, is added to the spectral model. We obtain similar goodness of fit for any of these three models, but the model including Compton reflection from cold material offers the simplest, physically self-consistent solution, because it only requires one reprocessing region. Thus the Fe K spectral features in Mrk 205 and Mrk 509 do not present strong evidence for reprocessing in the inner, relativistic parts of accretion disks.Comment: accepted for publication in MNRA

Clinical and biological significance of miR-23b and miR-193a in human hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common cancer of the liver with a very poor prognosis. The dysregulation of microRNAs (miRs) is indeed implicated in HCC onset and progression. In this study, we have evaluated the expression of miR-23b and miR-193a in a large cohort of 59 and 67 HCC patients, respectively. miR-23b and miR-193a resulted significantly down-regulated in primary HCCs compared to their matched peritumoral counterparts. Furthermore, patients with higher miR-193a expression exhibited longer OS and DFS, suggesting that miR-193a may be a molecular prognostic factor for HCC patients. Since the regulation of miRs by DNA methylation may occur in human cancers, we verified whether the down-modulation of miR-23b and miR-193a in HCC tissues could be related to DNA methylation. An inverse trend between miR-23b expression and DNA methylation was observed, indicating that miR-23b can be epigenetically regulated. By contrast, the down-regulation of miR-193a was not mediated by DNA methylation. To verify the potential role of miR-23b and miR-193a as responsive molecular targets in vitro, we used the inhibitor of DNA methylation 5-aza-dC to restore miR-23b expression level in combination with miR-193a transfection. The combined treatment led to a significant inhibition of cellular proliferation and migration. Taken together, our findings provide evidence that miR-23b and miR-193a may be molecular diagnostic and prognostic factors for HCC; furthermore, miR-23b and miR-193a are responsive molecular targets for limiting HCC cell aggressiveness in combination with the epigenetic drug 5-aza-dC. Moreover, our results provide new advances in the epigenetic regulation of these miRs in HCC

Canceling the cavity length induced phase noise in an optical ring cavity for phase shift measurement and spin squeezing

We demonstrate a new method of light phase shift measurement using a high-finesse optical ring cavity which exhibits reduced phase noise due to cavity length fluctuations. Two laser beams with a frequency difference of one cavity free spectral range are simultaneously resonant with the cavity, demonstrating noise correlations in the error signals due to the common-mode cavity length fluctuations. The differential error signal shows a 30 dB reduction in cavity noise down to the noise floor in a frequency range up to half the cavity linewidth ($\delta\nu/2 \simeq 30$ kHz). Various noise sources are analyzed and their contributions to the noise floor are evaluated. Additionally, we apply this noise-reduced phase shift measurement scheme in a simulated spin-squeezing experiment where we have achieved a factor of 40 improvement in phase sensitivity with a phase resolution of 0.7 mrad, which may remove one important barrier against attaining highly spin-squeezed states. The demonstrated method is the first reported measurement using an optical ring cavity and two independent beams, a flexible situation. This method can find direct application to non-destructive measurements in quantum systems, such as for the generation of spin-squeezed states in atom interferometers and atomic clocks.Comment: 9 pages, 5 figure

High Density Planting in Mango cv. Alphonso

A trial was conducted to optimize spacing for high density planting in mango cv. Alphonso to obtain higher yield/ unit area at the Agriculture Research Station, Mulde, during 2006-07 to 2008-09 with four close spacings and one normal spacing as control. Highest yield (6.4 MT/ha) was recorded with a spacing of 5 m x 5 m without reduction in fruit size in 10 year old plants compared to the mean yield of 1.12 MT/ha in 10m x 10m normal spacing. High density plantation helped to get significantly higher yield per unit area compared to the normal spacing, without affecting size and quality of mango fruits. The highest cost:benefit ratio (2.33) was recorded in high density plantation of 5m x 5m, with maximum net returns of Rs.1,12,000/- per hectare. The present findings show promise for more yield and returns per unit area during the initial years of mango plantation by adopting 5m x 5m high density planting

Comparative Performance of Mango Varieties Grafted on Vellaikolamban and Mixed Rootstock

Research on rootstock in mango is very limited in our country. Kalapady was reported to be a dwarfing rootstock. Recent trend among mango growers is to high density orcharding with dwarfening nature of the varietie. Efforts were made at Agriculture Research Station, Mulde, to study comparative performance of Ratna, Alphonso and Kesar mango on Vellaikolamban and mixed rootstock i.e., heterozygous seedling stock and the effect of rootstock on a scion under high density of 5m x 5m spacing. Results indicated that use of Vellaikolamban rootstock reduced plant volume in scion cv. Alphonso by 39.1%, followed by 24.9% in Ratna and 26.5% in cv. Kesar. As volume of the canopy was reduced, it directly influenced fruit yield cvs. Alphonso and Ratna. However, reduction in canopy volume had a positive influence on yield in cv. Kesar. Net returns of Rs.38,629/- per ha were maximum for Kesar with the rootstock Vellaikolamban